JPH0867223A - Measurememt of inter-vehicle distance - Google Patents

Abstract

PURPOSE: To reduce the erroneous measurement for the distance up to a measured object by discriminating the measured object as a small obstacle, large obstacle or the road affiliated equipment, on the basis of the unevenness of the distance to the measured object from the vehicle in each radiation angle. CONSTITUTION: The near infrared ray is radiated from a light radiation part 1 by the pulse signal of a pulse driving part 3, moving an irrdiation plate inside the light radiation part 1 by each angle in six directions by a motor 23 for the radiation plate driven by a driving part 21 for the radiation plate. The reflected light is received by a light receiving part 5, and the time is sent into an A/D conversion part 9 through a time/voltage conversion part 7. While, the own vehicle speed detected by an own vehicle speed detection part 25 is converted to the digital value by the A/D conversion part 9. The time up to the receiving of the light by the light receiving part 5 is calculated as the distance to a measured object from the light speed and the own vehicle speed by a calculation processing part 11, and is displayed by a display part 51. Accordingly, the dimension and the moving state of an obstacle can be judged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention discriminates an object to be measured on a vehicle, an obstacle, a guardrail, etc., measures and displays the distance to the object to be measured, and further, the distance between the vehicle and the object to be measured. The distance measurement method that displays the degree of danger and issues an alarm.

[0002]

2. Description of the Related Art Conventionally, as a device for measuring an inter-vehicle distance of an object to be measured such as an own vehicle and another vehicle, there is an ultrasonic type inter-vehicle distance measuring device which is generally commercially available as an ultrasonic wave. . This ultrasonic inter-vehicle distance measuring device transmits ultrasonic waves to a DUT from a vibrator that generates ultrasonic waves by vibration, and receives the reflected waves of the ultrasonic waves reflected by the DUT to measure the vehicle To the object to be measured,
This distance was displayed and an alarm was issued to alert the driver when the vehicle was about to collide with the object to be measured.

However, in such a measuring device,
There are problems such as malfunction due to ultrasonic waves used for automatic doors and the like, and the frequency of the ultrasonic waves causes the animal such as a dog or cat to become a neurose due to the audible range of the animal.

In order to solve this problem, there is an optical inter-vehicle distance measuring device using laser light. This optical distance measuring device is provided with one or three laser diodes for irradiating the object to be measured with laser light, and irradiates one or three laser light from this laser diode,
The distance from the vehicle to the measured object is measured by the time until the reflected light of the laser light reflected by the measured object is received. Therefore, this device does not interfere with the ultrasonic waves used for automatic doors, etc., and also displays the distance from the vehicle to the object to be measured, and the vehicle does not interfere with the object to be measured. The driver can now be alerted if there is a possible collision with the car.

[0005]

However, in this optical inter-vehicle distance measuring device, the laser beam is simply applied to the object to be measured and the reflected light from the object is detected to detect the reflected light from the vehicle. Since the vehicle-to-vehicle distance to the object to be measured was measured, road incidental equipment such as guardrails, traffic signs and safety fences with wires that do not hinder driving of the vehicle and other vehicles or vehicles Since it is not possible to determine the type of the measured object such as an obstacle that may interfere with driving, even if you try to measure the inter-vehicle distance from your vehicle to another vehicle, the distance from your vehicle to the road auxiliary equipment is erroneously measured. However, there were many false alarms.

Therefore, an object of the present invention is to reduce the erroneous measurement by discriminating that the object to be measured is a road auxiliary equipment or another vehicle and displaying the distance to the object to be measured, and further, truely. An object of the present invention is to provide a method for measuring an inter-vehicle distance with few false alarms by displaying a degree of danger according to a distance between an object to be measured and a vehicle that is an obstacle to traveling and issuing an alarm.

[0007]

The present invention for achieving the above object is based on the following means.

1. Vehicle-to-vehicle distance using a vehicle-to-vehicle distance measuring device that is mounted on a vehicle and measures the distance from the vehicle to the measured object based on the time from the irradiation of light to the reception of the reflected light reflected by the measured object. In the distance measuring method, irradiating the object to be measured with variable irradiation angle, receiving the reflected light reflected by the object to be measured, and based on the time from the irradiation of the light to the reception of the light. Measure the distance from the vehicle to the DUT for each irradiation angle,
Small obstacles that may interfere with the traveling of the vehicle due to irregularities in the distance of the measured object from the vehicle for each measured irradiation angle, large obstacles that interfere with the traveling of the vehicle, and It is characterized in that it is discriminated as one of road auxiliary equipment installed along a road which does not hinder the traveling of the vehicle.

2. Vehicle-to-vehicle distance using a vehicle-to-vehicle distance measuring device that is mounted on a vehicle and measures the distance from the vehicle to the measured object based on the time from the irradiation of light to the reception of the reflected light reflected by the measured object. In the distance measuring method, irradiating the object to be measured with variable irradiation angle, receiving the reflected light reflected by the object to be measured, and based on the time from the irradiation of the light to the reception of the light. Measure the distance from the vehicle to the DUT for each irradiation angle,
The distance from the vehicle to the object to be measured for each corresponding irradiation angle measured this time is subtracted from the distance from the vehicle to the object to be measured for each irradiation angle measured last time, and the subtracted irradiation angle for each object. If the difference between the distance and the moving distance of the vehicle from the time of the previous measurement to the time of the current measurement is compared, and if the difference in the distance in at least one direction is larger than the set value among the compared distances, The object to be measured is determined to be another vehicle that is traveling in front of the vehicle, and the object to be measured that is not determined to be the other vehicle is determined to be a fixed object that does not move on or near the road, For the measured object that is determined to be the fixed object, of the differences in the compared distances, 1
Alternatively, when the difference between the distances in the two directions is equal to or less than the set value, the fixed object is determined to be a small obstacle that may interfere with the traveling of the vehicle, and the fixed object is not determined to be the small obstacle. If the distance to the object to be measured for each irradiation angle measured this time with respect to the fixed object does not fall within a certain range, the fixed object is a major obstacle to the traveling of the vehicle. If the deviation is within a certain range by auto-regressing the distance to the object to be measured for each irradiation angle measured this time, with respect to the fixed object that is determined to be an object and is not determined to be the small obstacle, It is characterized in that the fixed object is determined to be a road auxiliary equipment that does not hinder the traveling of the vehicle.

3. Vehicle-to-vehicle distance using a vehicle-to-vehicle distance measuring device that is mounted on a vehicle and measures the distance from the vehicle to the measured object based on the time from the irradiation of light to the reception of the reflected light reflected by the measured object. In the distance measuring method, irradiating the object to be measured with variable irradiation angle, receiving the reflected light reflected by the object to be measured, and based on the time from the irradiation of the light to the reception of the light. Measure the distance from the vehicle to the DUT for each irradiation angle,
The distance from the vehicle to the measured object for each corresponding irradiation angle measured this time is subtracted from the distance from the vehicle to the measured object for each irradiation angle measured last time, and the subtracted irradiation angle for each measured irradiation angle. If the difference between the distance and the travel distance of the vehicle from the time of the previous measurement to the time of the present measurement is compared, and if the difference in the distance in at least one direction is larger than the set value among the differences in the compared distances, When it is determined that the DUT is another vehicle traveling in front of the vehicle, and the distance from the vehicle to the other vehicle is smaller than the inter-vehicle distance at which the vehicle can stop without hitting the other vehicle. It is characterized by displaying that the other vehicle is present at a distance where there is a danger of collision and giving an alarm, and displaying the distance from the vehicle to the other vehicle.

4. Vehicle-to-vehicle distance using a vehicle-to-vehicle distance measuring device that is mounted on a vehicle and measures the distance from the vehicle to the measured object based on the time from the irradiation of light to the reception of the reflected light reflected by the measured object. In the distance measuring method, irradiating the object to be measured with variable irradiation angle, receiving the reflected light reflected by the object to be measured, and based on the time from the irradiation of the light to the reception of the light. Measure the distance from the vehicle to the DUT for each irradiation angle,
The distance from the vehicle to the object to be measured for each corresponding irradiation angle measured this time is subtracted from the distance from the vehicle to the object to be measured for each irradiation angle measured last time, and the subtracted irradiation angle for each object. If the difference between the distance and the moving distance of the vehicle from the time of the previous measurement to the time of the current measurement is compared, and if the difference in the distance in at least one direction is larger than the set value among the compared distances, The object to be measured is determined to be another vehicle that is traveling in front of the vehicle, and the object to be measured that is not determined to be the other vehicle is determined to be a fixed object that does not move on or near the road, For the measured object that is determined to be the fixed object, of the differences in the compared distances, 1
Alternatively, when the difference between the distances in the two directions is equal to or less than the set value, it is determined that the fixed object is a small obstacle that may interfere with the traveling of the vehicle, and the small obstacle is not determined. When the distance to the object to be measured for each irradiation angle measured this time with respect to the fixed object regresses and the deviation does not fall within a certain range, the fixed object is a major obstacle to the traveling of the vehicle. If the distance from the vehicle to the small obstacle or the large obstacle is smaller than the inter-vehicle distance that can stop without hitting the small obstacle or the large obstacle, there is a risk of a rear-end collision. It is characterized by displaying that there is the small obstacle or the large obstacle at a certain distance and issuing an alarm, and displaying the distance from the vehicle to the small obstacle or the large obstacle.

5. Vehicle-to-vehicle distance using a vehicle-to-vehicle distance measuring device that is mounted on a vehicle and measures the distance from the vehicle to the measured object based on the time from the irradiation of light to the reception of the reflected light reflected by the measured object. In the distance measuring method, irradiating the object to be measured with variable irradiation angle, receiving the reflected light reflected by the object to be measured, and based on the time from the irradiation of the light to the reception of the light. Measure the distance from the vehicle to the DUT for each irradiation angle,
The distance from the vehicle to the object to be measured for each corresponding irradiation angle measured this time is subtracted from the distance from the vehicle to the object to be measured for each irradiation angle measured last time, and the subtracted irradiation angle for each object. If the difference between the distance and the moving distance of the vehicle from the time of the previous measurement to the time of the current measurement is compared, and if the difference in the distance in at least one direction is larger than the set value among the compared distances, When it is determined that the DUT is another vehicle traveling in front of the vehicle, and the distance from the vehicle to the other vehicle is smaller than the inter-vehicle distance at which the vehicle can stop without hitting the other vehicle. , Indicating that there is another vehicle at a distance where there is a danger of collision and issuing an alarm, and displaying the distance from the vehicle to the other vehicle,
The object to be measured that is not distinguished from the other vehicle is determined as a stationary object that is located on or near the road and does not move, and the object to be measured that is determined to be the fixed object is the difference in the compared distance. If the difference between the distances in one or two directions is less than or equal to the set value, it is determined that the fixed object is a small obstacle that may interfere with the traveling of the vehicle, and For the non-determined fixed object, if the deviation does not fall within a certain range by auto-regressing the distance to the measured object for each irradiation angle measured this time, the fixed object is an obstacle to traveling of the vehicle. If the distance from the vehicle to the small obstacle or the large obstacle is smaller than the inter-vehicle distance at which the vehicle can stop without colliding with the small obstacle or the large obstacle, a rear-end collision is determined. The small obstacle at a risk of Or said with displays that a major obstacle is alert, and displaying a distance from said vehicle to said small obstacle or the large obstacle.

6. Vehicle-to-vehicle distance using a vehicle-to-vehicle distance measuring device that is mounted on a vehicle and measures the distance from the vehicle to the measured object based on the time from the irradiation of light to the reception of the reflected light reflected by the measured object. In the distance measuring method, irradiating the object to be measured with variable irradiation angle, receiving the reflected light reflected by the object to be measured, and based on the time from the irradiation of the light to the reception of the light. Measure the distance from the vehicle to the DUT for each irradiation angle,
The distance from the vehicle to the object to be measured for each corresponding irradiation angle measured this time is subtracted from the distance from the vehicle to the object to be measured for each irradiation angle measured last time, and the subtracted irradiation angle for each object. If the difference between the distance and the moving distance of the vehicle from the time of the previous measurement to the time of the current measurement is compared, and if the difference in the distance in at least one direction is larger than the set value among the compared distances, When it is determined that the DUT is another vehicle traveling in front of the vehicle, and the distance from the vehicle to the other vehicle is smaller than the inter-vehicle distance at which the vehicle can stop without hitting the other vehicle. Displaying the degree of danger of the vehicle colliding with the other vehicle according to the magnitude of the difference in speed between the vehicle and the other vehicle and issuing an alarm, and displaying the distance from the vehicle to the other vehicle. Characterized by

7. Vehicle-to-vehicle distance using a vehicle-to-vehicle distance measuring device that is mounted on a vehicle and measures the distance from the vehicle to the measured object based on the time from the irradiation of light to the reception of the reflected light reflected by the measured object. In the distance measuring method, irradiating the object to be measured with variable irradiation angle, receiving the reflected light reflected by the object to be measured, and based on the time from the irradiation of the light to the reception of the light. Measure the distance from the vehicle to the DUT for each irradiation angle,
The distance from the vehicle to the object to be measured for each corresponding irradiation angle measured this time is subtracted from the distance from the vehicle to the object to be measured for each irradiation angle measured last time, and the subtracted irradiation angle for each object. If the difference between the distance and the moving distance of the vehicle from the time of the previous measurement to the time of the current measurement is compared, and if the difference in the distance in at least one direction is larger than the set value among the compared distances, The object to be measured is determined to be another vehicle that is traveling in front of the vehicle, and the object to be measured that is not determined to be the other vehicle is determined to be a fixed object that does not move on or near the road, For the measured object that is determined to be the fixed object, of the differences in the compared distances, 1
Alternatively, when the difference between the distances in the two directions is equal to or less than the set value, it is determined that the fixed object is a small obstacle that may interfere with the traveling of the vehicle, and the small obstacle is not determined. When the distance to the object to be measured for each irradiation angle measured this time with respect to the fixed object regresses and the deviation does not fall within a certain range, the fixed object is a major obstacle to the traveling of the vehicle. If the distance from the vehicle to the small obstacle or the large obstacle is smaller than the inter-vehicle distance that can be stopped without hitting the small obstacle or the large obstacle, the speed of the vehicle The degree of danger that the vehicle will collide with the small obstacle or the large obstacle according to the size of the above, and gives an alarm, and also displays the distance from the vehicle to the small obstacle or the large obstacle. Characterized by

8. Vehicle-to-vehicle distance using a vehicle-to-vehicle distance measuring device that is mounted on a vehicle and measures the distance from the vehicle to the measured object based on the time from the irradiation of light to the reception of the reflected light reflected by the measured object. In the distance measuring method, irradiating the object to be measured with variable irradiation angle, receiving the reflected light reflected by the object to be measured, and based on the time from the irradiation of the light to the reception of the light. Measure the distance from the vehicle to the DUT for each irradiation angle,
The distance from the vehicle to the measured object for each corresponding irradiation angle measured this time is subtracted from the distance from the vehicle to the measured object for each irradiation angle measured last time, and the subtracted irradiation angle for each measured irradiation angle. If the difference between the distance and the travel distance of the vehicle from the time of the previous measurement to the time of the present measurement is compared, and if the difference in the distance in at least one direction is larger than the set value among the differences in the compared distances, The object to be measured is determined to be another vehicle traveling in front of the vehicle, and the inter-vehicle distance at which the vehicle can stop without hitting the other vehicle due to weather is corrected, and the vehicle to the other vehicle is corrected. If the distance to is smaller than the corrected inter-vehicle distance that can be stopped without a rear-end collision, the degree of risk of the rear-end collision of the vehicle with the another-vehicle is determined according to the magnitude of the difference in speed between the vehicle and the another-vehicle. Display and alarm Together to, and displaying the distance to the other vehicle from the vehicle.

9. Vehicle-to-vehicle distance using a vehicle-to-vehicle distance measuring device that is mounted on a vehicle and measures the distance from the vehicle to the measured object based on the time from the irradiation of light to the reception of the reflected light reflected by the measured object. In the distance measuring method, irradiating the object to be measured with variable irradiation angle, receiving the reflected light reflected by the object to be measured, and based on the time from the irradiation of the light to the reception of the light. Measure the distance from the vehicle to the DUT for each irradiation angle,
The distance from the vehicle to the object to be measured for each corresponding irradiation angle measured this time is subtracted from the distance from the vehicle to the object to be measured for each irradiation angle measured last time, and the subtracted irradiation angle for each object. If the difference between the distance and the moving distance of the vehicle from the time of the previous measurement to the time of the current measurement is compared, and if the difference in the distance in at least one direction is larger than the set value among the compared distances, The object to be measured is determined to be another vehicle that is traveling in front of the vehicle, and the object to be measured that is not determined to be the other vehicle is determined to be a fixed object that does not move on or near the road, For the measured object that is determined to be the fixed object, of the differences in the compared distances, 1
Alternatively, when the difference between the distances in the two directions is equal to or less than the set value, it is determined that the fixed object is a small obstacle that may interfere with the traveling of the vehicle, and the small obstacle is not determined. When the distance to the object to be measured for each irradiation angle measured this time with respect to the fixed object regresses and the deviation does not fall within a certain range, the fixed object is a major obstacle to the traveling of the vehicle. It is determined that it is an object, the vehicle distance is corrected depending on the weather without stopping the vehicle from hitting the small obstacle or the large obstacle, and the distance from the vehicle to the small obstacle or the large obstacle is concerned. If it is smaller than the corrected inter-vehicle distance that can be stopped without a rear-end collision, the degree of danger of the rear-end collision of the vehicle with the small obstacle or the large obstacle is displayed according to the speed of the vehicle, and an alarm is issued. Before Displaying the distance to the small obstacle or the large obstacle.

10. Vehicle-to-vehicle distance using a vehicle-to-vehicle distance measuring device that is mounted on a vehicle and measures the distance from the vehicle to the measured object based on the time from the irradiation of light to the reception of the reflected light reflected by the measured object. In the distance measuring method, irradiating the object to be measured with variable irradiation angle, receiving the reflected light reflected by the object to be measured, and based on the time from the irradiation of the light to the reception of the light. Measure the distance from the vehicle to the DUT for each irradiation angle,
The distance from the vehicle to the object to be measured for each corresponding irradiation angle measured this time is subtracted from the distance from the vehicle to the object to be measured for each irradiation angle measured last time, and the subtracted irradiation angle for each object. If the difference between the distance and the moving distance of the vehicle from the time of the previous measurement to the time of the current measurement is compared, and if the difference in the distance in at least one direction is larger than the set value among the compared distances, When it is determined that the DUT is another vehicle traveling in front of the vehicle, and the distance from the vehicle to the other vehicle is smaller than the inter-vehicle distance at which the vehicle can stop without hitting the other vehicle. Displaying the degree of danger of the vehicle colliding with the other vehicle according to the magnitude of the difference in speed between the vehicle and the other vehicle and issuing an alarm, and displaying the distance from the vehicle to the other vehicle. Then
The object to be measured that is not distinguished from the other vehicle is determined as a stationary object that is located on or near the road and does not move, and the object to be measured that is determined to be the fixed object is the difference in the compared distance. If the difference between the distances in one or two directions is less than or equal to the set value, it is determined that the fixed object is a small obstacle that may interfere with the traveling of the vehicle, and For the non-determined fixed object, if the deviation does not fall within a certain range by auto-regressing the distance to the measured object for each irradiation angle measured this time, the fixed object is an obstacle to traveling of the vehicle. When the distance from the vehicle to the small obstacle or the large obstacle is smaller than the inter-vehicle distance that can be stopped without hitting the small obstacle or the large obstacle, The vehicle according to the speed of the vehicle Wherein with displaying the degree of risk of collision in a small obstacle or the large obstacle alerting, and displaying a distance from said vehicle to said small obstacle or the large obstacle.

11. Vehicle-to-vehicle distance using a vehicle-to-vehicle distance measuring device that is mounted on a vehicle and measures the distance from the vehicle to the measured object based on the time from the irradiation of light to the reception of the reflected light reflected by the measured object. In the distance measuring method, irradiating the object to be measured with variable irradiation angle, receiving the reflected light reflected by the object to be measured, and based on the time from the irradiation of the light to the reception of the light. Measure the distance from the vehicle to the DUT for each irradiation angle,
The distance from the vehicle to the measured object for each corresponding irradiation angle measured this time is subtracted from the distance from the vehicle to the measured object for each irradiation angle measured last time, and the subtracted irradiation angle for each measured irradiation angle. If the difference between the distance and the travel distance of the vehicle from the time of the previous measurement to the time of the present measurement is compared, and if the difference in the distance in at least one direction is larger than the set value among the differences in the compared distances, The object to be measured is determined to be another vehicle traveling in front of the vehicle, and the inter-vehicle distance at which the vehicle can stop without hitting the other vehicle due to weather is corrected, and the vehicle to the other vehicle is corrected. If the distance to is smaller than the corrected inter-vehicle distance that can be stopped without a rear-end collision, the degree of risk of the rear-end collision of the vehicle with the another-vehicle is determined according to the magnitude of the difference in speed between the vehicle and the another-vehicle. Display and alarm At the same time, the distance from the vehicle to the other vehicle is displayed, and the object to be measured that is not distinguished from the other vehicle is determined as a fixed object that is located on or near the road and does not move, and is determined as the fixed object. If the difference between the distances in the one or two directions is less than or equal to a set value among the compared distance differences with respect to the measured object, the fixed object becomes an obstacle to the traveling of the vehicle. Sometimes it is determined that it is a small obstacle, the fixed object that is not discriminated as the small obstacle, self-regresses the distance to the measured object for each irradiation angle measured this time, and the deviation is within a certain range. If it does not enter, it determines that the fixed object is a large obstacle that interferes with the traveling of the vehicle, and corrects the inter-vehicle distance that the vehicle can stop without hitting the small obstacle or the large obstacle due to the weather. From the vehicle to the small obstacle If the distance to the large obstacle is smaller than the inter-vehicle distance that can be stopped without colliding with the small obstacle or the large obstacle, the vehicle becomes the small obstacle or the large obstacle according to the speed of the vehicle. It is characterized in that the degree of danger of rear-end collision is displayed and an alarm is issued, and the distance from the vehicle to the small obstacle or the large obstacle is displayed.

[0019]

The inter-vehicle distance measuring method of the present invention constructed as described above operates as follows.

1. This method irradiates the object to be measured with variable irradiation angle, receives the reflected light reflected by the object to be measured, and determines the self-timer for each irradiation angle based on the time from the irradiation of light to the reception of light. By measuring the unevenness of the distance from the vehicle to the object to be measured, it is possible to know the arrangement of the object to be measured around the road. Therefore, the type of the object to be measured may hinder the running of the vehicle from this arrangement. It is possible to distinguish between small obstacles, large obstacles that hinder the running of the vehicle, and road auxiliary equipment that is installed along the road that does not hinder the running of the vehicle. It is possible to reduce erroneous measurement of the distance to the measurement object.

2. This method irradiates the object to be measured with variable irradiation angle, receives the reflected light reflected by the object to be measured, and determines the self-timer for each irradiation angle based on the time from the irradiation of light to the reception of light. Measure the distance from the car to the DUT,
The distance from the vehicle to the object to be measured for each corresponding irradiation angle measured this time is subtracted from the previously measured distance from the vehicle to the object to be measured for each irradiation angle. Compare the distance traveled by your vehicle from the previous measurement to the current measurement. This difference in distance is equal when the object to be measured is a fixed object without considering the measurement error, and when the object to be measured is another vehicle, even if the maximum speed of the car etc. is taken into consideration The time difference should not change very rapidly due to the small amount of time. Therefore, it can be determined that the objects having the same compared distance difference are fixed objects such as obstacles, and the objects having the different distance differences are other vehicles. If the difference between the distances in the one or two directions is less than or equal to the set value among the compared distances with respect to the measured object that is determined to be the fixed object, the measured object is driven by the vehicle. It is determined that the obstacle is a small obstacle that may be an obstacle. Also,
For a fixed object that is not discriminated as a small obstacle, the deviation that is the change amount of the light reflection surface of the measured object is judged by autoregressing the distance to the measured object for each irradiation angle measured this time. If is not within a certain range, it is determined to be a large obstacle on the road that has a certain width and is an obstacle to the traveling of the own vehicle. Furthermore, for a fixed object that is not identified as a small obstacle, the deviation, which is the amount of change in the light reflection surface of the measured object, is determined by autoregressing the distance to the measured object for each irradiation angle measured this time. When the deviation is within a certain range, it is possible to determine that the measured object is a road auxiliary equipment such as a guardrail that does not hinder the running of the vehicle.

Therefore, the present method can accurately determine that the object to be measured is an obstacle such as an obstacle to the traveling of the own vehicle and a road auxiliary equipment such as a guard rail which does not hinder the traveling of the vehicle. Thus, erroneous measurement of the distance to the object to be measured can be reduced.

3. This method irradiates light to the DUT while changing the irradiation angle, receives the reflected light reflected by the DUT, and detects the reflected light reflected by the DUT, based on the time from the light irradiation to the light reception. To the object to be measured, and subtract the distance from the vehicle to the object to be measured at the corresponding irradiation angle measured this time from the distance from the vehicle to the object to be measured at each irradiation angle measured last time. To do. This subtracted distance for each irradiation angle should not change drastically when the object to be measured is another vehicle, even if the maximum speed of the vehicle etc. is taken into consideration, because the measurement time difference between the previous time and this time is a little time. . Therefore, of the subtracted distances for each irradiation angle, those that are not equal can be determined to be other vehicles. Furthermore, by setting in advance the distance at which the vehicle can be stopped without a rear-end collision according to the distance from the own vehicle to another vehicle, it is possible to warn a driver or the like of a dangerous traveling state.

Therefore, in the present method, when the distance from the own vehicle to another vehicle is smaller than the inter-vehicle distance at which the vehicle can be stopped without colliding with the other vehicle, it is displayed and an alarm is issued to indicate that there is another vehicle at a risk of collision. And the distance to the other vehicle is displayed, the risk of a rear-end collision with the other vehicle can be prevented.

4. This method irradiates the object to be measured with variable irradiation angle, receives the reflected light reflected by the object to be measured, and determines the vehicle for each irradiation angle based on the time from the irradiation of light to the reception of light. To the object to be measured, and subtract the distance from the vehicle to the object to be measured at the corresponding irradiation angle measured this time from the distance from the vehicle to the object to be measured at each irradiation angle measured last time. Then, the distance for each irradiation angle thus subtracted is compared with the moving distance of the vehicle from the previous measurement to the current measurement. The difference in the compared distances becomes equal when the object to be measured is a fixed object without taking measurement error into consideration. Therefore, it is possible to determine that objects having the same difference in the above-mentioned compared distances are fixed objects. Further, when the difference between the distances in the one or two directions is less than or equal to the set value among the compared distance differences with respect to the measured object determined to be a fixed object, the measured object is driven by the vehicle. It is determined that the obstacle is a small obstacle that may be an obstacle. In addition, for a fixed object that is not discriminated as a small obstacle, the deviation, which is the amount of change in the light reflection surface of the measured object, is determined by auto-regressing the distance to the measured object for each irradiation angle measured this time. When the deviation is within the set value, it is determined that the vehicle is a large obstacle that has a certain width on the road and interferes with the running of the vehicle.

Therefore, according to this method, the distance from the own vehicle to the obstacle is set by presetting the distance at which the vehicle can be stopped without a rear-end collision according to the distance from the own vehicle to the obstacle. If it is smaller than the inter-vehicle distance that can be stopped without hitting the car, it will indicate that there is an obstacle at the distance where there is a danger of hitting, issue an alarm, and display the distance from the own vehicle to the obstacle, so hit the obstacle. Danger can be prevented beforehand.

5. This method irradiates the object to be measured with variable irradiation angle, receives the reflected light reflected by the object to be measured, and outputs from the vehicle for each irradiation angle based on the time from the irradiation of light to the reception of light. Measure the distance to the object to be measured, and subtract the distance from the vehicle to the object to be measured at the corresponding irradiation angle measured this time from the distance from the vehicle to the object to be measured at each irradiation angle measured last time. , The subtracted distance for each irradiation angle is compared with the moving distance of the vehicle from the previous measurement to the current measurement. This difference in distance is equal when the object to be measured is a fixed object without considering the measurement error, and when the object to be measured is another vehicle, even if the maximum speed of the car etc. is taken into consideration The time difference should not change very rapidly due to the small amount of time. Therefore, it is possible to determine that those having the same difference in the above-mentioned compared distances are fixed objects, and those that are not equal are other vehicles. Then, by setting in advance a distance at which the vehicle can be stopped without a rear-end collision according to the distance from the own vehicle to another vehicle, it is possible to warn the driver or the like of a dangerous traveling state.

Therefore, when the distance from the own vehicle to the other vehicle is smaller than the inter-vehicle distance at which the other vehicle can stop without hitting the other vehicle, the present method displays that there is another vehicle at a distance where there is a risk of hitting another vehicle and issues an alarm. And the distance from the own vehicle to the other vehicle is displayed, the danger of a rear-end collision with the other vehicle can be prevented.

Further, if the difference in the distances in one or two directions is less than or equal to the set value among the differences in the distances compared with the object to be measured which is determined to be a fixed object, the measurement object is It is determined that the obstacle is a small obstacle that may interfere with the running of the vehicle. Also, for fixed objects that are not distinguished as small obstacles,
The deviation, which is the amount of change in the light reflecting surface of the object to be measured, is judged by autoregressing the distance to the object to be measured for each irradiation angle measured this time, and when the deviation is within the set value, a certain value on the road is maintained. It is determined that the obstacle is a large obstacle having a width and obstructing the traveling of the own vehicle.

Therefore, according to this method, the distance from the own vehicle to the obstacle is set by presetting the distance at which the vehicle can be stopped without a collision according to the distance from the own vehicle to the obstacle. If it is smaller than the inter-vehicle distance that can be stopped without hitting the car, it will indicate that there is an obstacle at the distance where there is a danger of hitting, issue an alarm, and display the distance from the own vehicle to the obstacle, so hit the obstacle. Danger can be prevented beforehand.

6. This method irradiates light to the DUT while changing the irradiation angle, receives the reflected light reflected by the DUT, and detects the reflected light reflected by the DUT, based on the time from the light irradiation to the light reception. To the object to be measured, and subtract the distance from the vehicle to the object to be measured at the corresponding irradiation angle measured this time from the distance from the vehicle to the object to be measured at each irradiation angle measured last time. To do. This subtracted distance for each irradiation angle should not change drastically when the object to be measured is another vehicle, even if the maximum speed of the vehicle etc. is taken into consideration, because the measurement time difference between the previous time and this time is a little time. . Therefore, of the subtracted distances for each irradiation angle, those that are not equal can be determined to be other vehicles.

Therefore, according to this method, the distance from the own vehicle to the other vehicle collides with the other vehicle by presetting the distance at which the vehicle can stop without the rear collision depending on the distance from the own vehicle to the other vehicle. If the distance is smaller than the distance that can be stopped without doing so, the degree of danger that the vehicle will collide with another vehicle will be displayed according to the speed difference between the vehicle and the other vehicle, and an alarm will be issued and Since the distance is displayed, the driver can deal with it according to the degree of danger of a rear-end collision with another vehicle, and dangerous driving such as a rear-end collision can be further reduced.

7. This method irradiates the object to be measured with variable irradiation angle, receives the reflected light reflected by the object to be measured, and determines the vehicle for each irradiation angle based on the time from the irradiation of light to the reception of light. To the object to be measured, and subtract the distance from the vehicle to the object to be measured at the corresponding irradiation angle measured this time from the distance from the vehicle to the object to be measured at each irradiation angle measured last time. Then, the distance for each irradiation angle thus subtracted is compared with the moving distance of the vehicle from the previous measurement to the current measurement. The difference in the compared distances becomes equal when the object to be measured is a fixed object without taking measurement error into consideration. Therefore, it is possible to determine that objects having the same difference in the above-mentioned compared distances are fixed objects. Furthermore, for the object to be measured that is determined to be a fixed object, one of
Alternatively, when the difference between the distances in the two directions is equal to or less than the set value, it is determined that the measured object is a small obstacle that may interfere with the traveling of the vehicle. In addition, for a fixed object that is not discriminated as a small obstacle, the deviation, which is the amount of change in the light reflection surface of the measured object, is determined by auto-regressing the distance to the measured object for each irradiation angle measured this time. When the deviation is within the set value, it is determined that the vehicle is a large obstacle that has a certain width on the road and interferes with the running of the vehicle.

Therefore, according to this method, the distance from the own vehicle to the obstacle collides with the obstacle by setting in advance the distance at which the vehicle can stop without colliding according to the distance from the own vehicle to the obstacle. If it is smaller than the inter-vehicle distance that can be stopped without doing so, the degree of danger that the own vehicle will collide with an obstacle will be displayed according to the speed of the own vehicle, an alarm will be issued, and the distance from the own vehicle to the obstacle will be displayed. The driver can take measures according to the degree of danger of collision with an object, and dangerous driving such as collision can be further reduced.

8. This method irradiates light to the DUT while changing the irradiation angle, receives the reflected light reflected by the DUT, and detects the reflected light reflected by the DUT, based on the time from the light irradiation to the light reception. To the object to be measured, and subtract the distance from the vehicle to the object to be measured at the corresponding irradiation angle measured this time from the distance from the vehicle to the object to be measured at each irradiation angle measured last time. . This subtracted distance for each irradiation angle should not change drastically when the object to be measured is another vehicle, even if the maximum speed of the vehicle etc. is taken into consideration, because the measurement time difference between the previous time and this time is a little time. . Therefore, of the subtracted distances for each irradiation angle, those that are not equal can be determined to be other vehicles. Furthermore, by setting in advance the distance at which the vehicle can be stopped without a rear-end collision according to the distance from the own vehicle to another vehicle, it is possible to warn a driver or the like of a dangerous traveling state.

Therefore, the present method corrects the inter-vehicle distance at which the own vehicle can stop without hitting another vehicle due to the weather, and when the distance from the own vehicle to the other vehicle is smaller than the corrected inter-vehicle distance without stopping after another collision. Displays the degree of danger that the own vehicle will collide with another vehicle according to the difference in speed between the own vehicle and the other vehicle, issues an alarm, and displays the distance from the own vehicle to the other vehicle for braking due to the weather. Since it also compensates for changes in distance, it can prevent rear-end collisions without being affected by the weather, and the driver can deal with it depending on the degree of risk of rear-end collisions with other vehicles, further reducing dangerous driving such as rear-end collisions. You can

9. This method irradiates the object to be measured with variable irradiation angle, receives the reflected light reflected by the object to be measured, and determines the vehicle for each irradiation angle based on the time from the irradiation of light to the reception of light. To the object to be measured, and subtract the distance from the vehicle to the object to be measured at the corresponding irradiation angle measured this time from the distance from the vehicle to the object to be measured at each irradiation angle measured last time. Then, the distance for each irradiation angle thus subtracted is compared with the moving distance of the vehicle from the previous measurement to the current measurement. The difference in the compared distances becomes equal when the object to be measured is a fixed object without taking measurement error into consideration. Therefore, it is possible to determine that objects having the same difference in the above-mentioned compared distances are fixed objects. Furthermore, for the object to be measured that is determined to be a fixed object, one of
Alternatively, when the difference between the distances in the two directions is equal to or less than the set value, it is determined that the measured object is a small obstacle that may interfere with the traveling of the vehicle. In addition, for a fixed object that is not discriminated as a small obstacle, the deviation, which is the amount of change in the light reflection surface of the measured object, is determined by auto-regressing the distance to the measured object for each irradiation angle measured this time. When the deviation is within the set value, it is determined that the vehicle is a large obstacle that has a certain width on the road and interferes with the running of the vehicle.

Therefore, according to the present method, the distance that can be stopped without a rear-end collision is set in advance according to the distance from the own-vehicle to the above-mentioned obstacle, and the inter-vehicle distance where the own-vehicle can stop without a rear-end collision with the obstacle. If the distance from your vehicle to the obstacle is smaller than the corrected inter-vehicle distance that allows you to stop without a rear-end collision, the degree of danger of your own rear-end collision with an obstacle is displayed according to the speed of your own vehicle and an alarm is displayed. By displaying the distance from the own vehicle to the obstacle as well as correcting the fluctuation of the braking distance due to the weather, it can prevent rear-end collision without being influenced by the weather and drive according to the degree of risk of rear-end collision with the obstacle. It is possible for the person to deal with it, and it is possible to further reduce dangerous driving such as a rear-end collision.

10. This method irradiates the object to be measured with variable irradiation angle, receives the reflected light reflected by the object to be measured, and determines the vehicle for each irradiation angle based on the time from the irradiation of light to the reception of light. To the object to be measured, and subtract the distance from the vehicle to the object to be measured at the corresponding irradiation angle measured this time from the distance from the vehicle to the object to be measured at each irradiation angle measured last time. Then, the distance for each irradiation angle thus subtracted is compared with the moving distance of the vehicle from the previous measurement to the current measurement. The difference in the compared distances is equal when the object to be measured is a fixed object without considering the measurement error,
When the object to be measured is another vehicle, even if the maximum speed of the vehicle is taken into consideration, the difference between the measurement time of the previous time and the measurement time of this time should not change very rapidly due to a short time. Therefore, it is possible to determine that those having the same difference in the above-mentioned compared distances are fixed objects, and those that are not equal are other vehicles.

Therefore, according to the present method, when the distance from the own vehicle to the other vehicle is smaller than the inter-vehicle distance at which the vehicle can be stopped without hitting the other vehicle, the own vehicle is determined according to the difference in speed between the own vehicle and the other vehicle. Displays the degree of danger of collision with another vehicle and issues an alarm and displays the distance from the own vehicle to the other vehicle, so the driver can deal with the degree of risk of collision with the other vehicle,
More dangerous driving such as a rear-end collision can be reduced.

If the difference in the distances in the one or two directions is less than or equal to the set value among the compared distance differences with respect to the measured object determined to be a fixed object, the measured object is It is determined that the obstacle is a small obstacle that may interfere with the running of the vehicle. And for fixed objects that are not distinguished as small obstacles,
The deviation, which is the amount of change in the light reflecting surface of the object to be measured, is judged by autoregressing the distance to the object to be measured for each irradiation angle measured this time, and when the deviation is within the set value, a certain value on the road is maintained. It is determined that the obstacle is a large obstacle having a width and obstructing the traveling of the own vehicle.

Therefore, according to the present method, when the distance from the vehicle to the obstacle is smaller than the inter-vehicle distance at which the vehicle can stop without hitting the obstacle, the vehicle hits the obstacle according to the speed of the vehicle. The degree of danger is displayed and an alarm is issued, and the distance from the vehicle to the obstacle is displayed, so the driver can deal with the obstacle depending on the degree of danger of colliding with the obstacle, and more dangerous driving such as rear collision can be performed. It can be reduced.

11. This method irradiates the object to be measured with variable irradiation angle, receives the reflected light reflected by the object to be measured, and determines the vehicle for each irradiation angle based on the time from the irradiation of light to the reception of light. To the object to be measured, and subtract the distance from the vehicle to the object to be measured at the corresponding irradiation angle measured this time from the distance from the vehicle to the object to be measured at each irradiation angle measured last time. Then, the distance for each irradiation angle thus subtracted is compared with the moving distance of the vehicle from the previous measurement to the current measurement. The difference in the compared distances is equal when the object to be measured is a fixed object without considering the measurement error,
When the object to be measured is another vehicle, even if the maximum speed of the vehicle is taken into consideration, the difference between the measurement time of the previous time and the measurement time of this time should not change very rapidly due to a short time. Therefore, it is possible to determine that those having the same difference in the above-mentioned compared distances are fixed objects, and those that are not equal are other vehicles.

Therefore, the present method corrects the inter-vehicle distance that the vehicle can stop without hitting another vehicle due to the weather, and when the distance from the own vehicle to the other vehicle is smaller than the corrected inter-vehicle distance that can stop without another collision. Displays the degree of danger that the own vehicle will collide with another vehicle according to the size of the speed difference between the own vehicle and the other vehicle and issues an alarm, and also displays the distance from the own vehicle to the other vehicle, depending on the weather. It also compensates for fluctuations in the braking distance, preventing rear-end collisions without being affected by the weather and allowing the driver to deal with the degree of risk of rear-end collisions with other vehicles, further reducing dangerous driving such as rear-end collisions. You can

If the difference in the distances in one or two directions is less than or equal to the set value among the measured distances that are determined to be fixed objects, the measured object is It is determined that the obstacle is a small obstacle that may interfere with the running of the vehicle. And for fixed objects that are not distinguished as small obstacles,
The deviation, which is the amount of change in the light reflecting surface of the object to be measured, is judged by autoregressing the distance to the object to be measured for each irradiation angle measured this time, and when the deviation is within the set value, a certain value on the road is maintained. It is determined that the obstacle is a large obstacle having a width and obstructing the traveling of the own vehicle.

Therefore, the present method further corrects the inter-vehicle distance that the vehicle can stop without hitting the above-mentioned obstacle due to the weather, and the distance from the own vehicle to the obstacle can be corrected from the inter-vehicle distance that can stop without hitting the obstacle. If it is small, the degree of danger of the vehicle colliding with an obstacle according to the speed of the vehicle is displayed and an alarm is issued, and the distance from the vehicle to the obstacle is displayed and the fluctuation of the braking distance due to the weather is also corrected. Therefore, the rear-end collision can be prevented without being influenced by the weather, and the driver can deal with it according to the degree of the risk of rear-end collision with the obstacle, thereby further reducing dangerous traveling such as rear-end collision.

[0047]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for measuring an inter-vehicle distance according to the present invention will be described below with reference to the drawings.

As an optical inter-vehicle distance measuring apparatus using this method, for example, as shown in FIG. 1, the irradiation angle of near infrared rays for irradiating a light source and an object to be measured with a diode and a lamp for generating near infrared rays such as laser light is used. A light irradiating section 1 having a variable irradiating plate, a pulse driving section 3 for causing the light irradiating section 1 to generate pulsed near infrared rays,
The light receiving section 5 for detecting the reflected light from the DUT and the time until the reflected light reflected by the DUT radiated from the light irradiating section 1 is detected by the light receiving section 5 are set as a voltage. And a time / voltage converter 7 for converting into a digital value and a signal from the time / voltage converter 7 into a digital value.
A conversion unit 9, a calculation processing unit 11 which is a calculation processing unit for processing the data from the A / D conversion unit 9 to calculate a distance, and determining the type of the object to be measured from the calculated distance, and a light irradiation unit. Irradiation plate motor 23 for driving the irradiation plate built in 1, and an irradiation plate drive unit 2 including a power element and a gate circuit for driving the irradiation plate motor 23.
1 and a vehicle speed detection unit 25 for detecting the speed of the vehicle.
And a display unit 51 for displaying the measured distance to the measured object and the degree of danger of the measured object and issuing an alarm.

The time / voltage conversion unit 7 is a semiconductor device composed of an integrating circuit and the like. The A / D conversion unit 9 is an A / D converter or the like, and the arithmetic processing unit 1
1 is a computing element such as a microcomputer and a digital signal processor. In addition, the display unit 51
Is composed of an LED, a cathode ray tube, a display such as a liquid crystal, and a speaker.

This device is mounted on vehicles such as automobiles, trucks and trains. For example, an irradiation plate driven by an irradiation plate drive unit 21 so that a road width of about 3.5 m can be measured near 100 m in front of this device. The irradiation plate inside the light irradiation unit 1 is moved once in six directions by the motor 23 for irradiation, and pulsed near infrared rays are emitted from the light irradiation unit 1 to the object to be measured in accordance with the pulse signal generated by the pulse drive unit 3. Then, the reflected light from the object to be measured is received by the light receiving unit 5, the time from irradiation to light reception at this time is converted into a voltage by the time / voltage conversion unit 7, and this time voltage signal is A / D converted. Part 9
Is converted into a digital value by. On the other hand, the vehicle speed detected by the vehicle speed detection unit 25 is converted into a digital value by the A / D conversion unit 9. The time until the near-infrared rays are emitted from the light emitting unit 1 converted into the digital value and received by the light receiving unit 5 is calculated by the arithmetic processing unit 11 as the distance to the object to be measured from the speed of light and the speed of the own vehicle. Is calculated.

In this method, as shown in the flow charts of FIGS. 2 and 3, the distances measured from the six directions and the first measured distances are L11, L21, L31, L41, L51, L61.
And the vehicle speed at the time of measurement is set to V1 (S1). Measure 6 directions again, and measure each distance for the second time by L
Let 12, L22, L32, L42, L52, L62 be the vehicle speed at the time of measurement V2 (S2). The vehicle speed VAG is VAG = (V1
+ V2) / 2 (S3), and the second measured value is subtracted from the first measured value for each irradiation angle (S3)
4) By calculating the short time t from the first measurement to the second measurement (S5), the moving distance VAGt of the vehicle from the first measurement to the second measurement is calculated. (S6). 1 if the DUT is a moving vehicle
In the second and second measurements, assuming that the distance from the vehicle to other vehicles does not change so much, the distance traveled by the vehicle and the distance measured by the irradiation angle If the difference between the changes in is within ± 1 m (S7), the object to be measured is determined as a stationary object (S8), and the difference between the distance traveled by the vehicle and the distance to the object is ± 1 m. If it does not fall within the range (S7), it is determined that the vehicle is running and another vehicle (S7).
9). When the same distance is measured from less than 3 directions among 6 irradiation directions (S10), it is determined that the measured object is a small obstacle that may interfere with the running of the vehicle (S11), and the irradiation directions are 6 directions. When the same distance is measured from three or more continuous directions (S10), the vehicle is installed along a road that does not obstruct the running of the vehicle or a large obstacle that may hinder the running of the vehicle. Obstacle determination subroutine processing for determining any of road-related equipment such as guardrails is performed (S12), and the distances measured for the second time are different for these other vehicles and the measurement object determined to be the aforementioned obstacles. L12 <25m, L62 <25m, L22 <40m, L52 <
If either 40 m, L32 <100 m, or L42 <100 m is met (S13), a risk judgment subroutine process for judging the degree of danger of collision in running the own vehicle and issuing an alarm is performed (S14). The second measured distance is L12 <25m, L62 <25m, L22 <
40m, L52 <40m, L32 <100m, L42 <100
If either of m is not satisfied (S13), the object to be measured is in a position that does not hinder the traveling of the own vehicle, and therefore the risk determination subroutine process is not performed.

In the obstacle determination subroutine processing, the distance traveled by the vehicle during the first and second measurement times and the amount of change in the second measured distance from the first measured distance become equal, as shown in the flowchart of FIG. Second measurement distance L12, L2
2, ... L62 is selected (S34), and the maximum value and the minimum value of the selected second measurement distance L12, L22, ... L62 are auto-regressed to obtain the distance deviation H, that is, the unevenness of the arrangement of the measured object ( S
35) If the deviation H does not fall within the range of ± 0.5 m (S36), the measured object is driven by the vehicle such as the wall in front of the vehicle at the T-shaped road as shown in FIG. If it is determined that the obstacle is a large obstacle (S38), and the deviation H is within a range of ± 0.5 m (S36), a road that does not hinder the running of the vehicle such as a guardrail as shown in FIG. When determining a hazard in the risk assessment subroutine of a road ancillary facility by determining 0.2 as the inter-vehicle distance d at the time of a safe stop, which is the vehicle-to-vehicle distance when the host vehicle is braked and stopped Is reduced (S37).

Therefore, the obstacle judging subroutine process judges the curvature which is the bending angle of the guardrail or the like by judging the unevenness of the light reflecting surface of the object to be measured, and judges the large obstacle such as the wall and the road incident such as the guardrail. When it is determined to be equipment, and when it is determined to be road-related equipment, the inter-vehicle distance d at the time of a safe stop is corrected to prevent erroneous determination, so erroneous measurement of the distance to the DUT and false alarms such as rear-end collisions are reduced. be able to.

Although the irradiation directions are six in this embodiment, they are not necessarily six directions and may be six or more directions.

When the object to be measured is another vehicle as shown in the flowchart of FIG. 7 (S41), the risk determining subroutine process is performed for another vehicle to determine the degree of danger to the other vehicle. Danger determination subroutine processing is performed (S42), and when the measured object is an obstacle (S4)
1) A risk determination subroutine process for anti-fixed objects for determining the degree of danger to obstacles is performed (S43).

In case of a rainy weather (S51) as shown in the flow charts of FIGS. 8 and 9, the danger judgment subroutine process for other vehicles is because the road surface is slippery due to water, so that the other vehicle at each speed as shown in FIG. Other vehicle braking distance f1 (V1) from when the vehicle brakes to stopping and the own vehicle braking distance f from when the vehicle brakes to stopping
2 (V2) is multiplied by 1.5 to correct the actual running state (S52), and when it is not raining (S5)
1), other vehicle braking distance f1 (V1) and own vehicle braking distance f
2 (V2) is not corrected, and the distance Lc from the own vehicle to another vehicle is measured (S53). When the deceleration of the host vehicle is 10% or more per second (S55), it is assumed that the vehicle is already decelerating, and the safe distance, which is a marginal distance with the other vehicle when the vehicle is safely stopped as shown in FIG. 11, is a safe inter-vehicle distance. D is D = f2 (V2)
It can be obtained from -f1 (V1) -d (S56),
When the deceleration of the own vehicle is less than 10% per second (S55), it is the distance that the own vehicle runs from the human judgment to the actual action of the body because the other vehicle is not aware of the existence of the other vehicle and the brake is not applied. If the free running distance is f3 (T), the safe inter-vehicle distance D is D = f2 (V2) + f3 (T) -f1 (V1)-
It can be obtained from d (S57). At this time, if the distance Lc to the other vehicle is equal to or greater than the safe inter-vehicle distance (S5
8) The safety warning display that the other vehicle is within the safe inter-vehicle distance and the distance Lc to the other vehicle are displayed (S59). Further, when the distance Lc to the other vehicle is less than the safe inter-vehicle distance (S58), the speed difference V3 between the own vehicle speed V2 and the other vehicle speed V1.
The speed difference V3 is compared with the own vehicle speed V as shown in FIG.
When it is larger than the rapid rear impact speed difference with respect to 2 (S6
0), a rear-end collision warning display indicating that there is another moving vehicle with a possibility of rear-end collision within the rapid rear-end collision distance, and the distance Lc to the other vehicle
Is displayed (S61), and when the speed difference V3 is smaller than the rapid rear-end collision speed difference with respect to the own vehicle speed V2 as shown in FIG. 12, (S61)
60), an inter-vehicle warning display indicating that another vehicle is moving within the rear-end collision distance and a distance Lc to the other vehicle are displayed (S6).
2).

Therefore, the safe inter-vehicle distance is corrected according to the weather and whether or not the host vehicle is currently within the range of the safe inter-vehicle distance is displayed and the inter-vehicle distance with the other vehicle is displayed. It is possible to reduce the dangerous driving of the vehicle and to display the degree of danger in the dangerous driving such as a rear-end collision due to the speed difference between the own vehicle and the other vehicle, and to give an alarm, so the driver can respond to the degree of the danger such as the rear-side collision in advance. By taking measures, it is possible to further reduce dangerous driving such as a rear-end collision.

It should be noted that it is desirable to set the free-running distance to an optimum value in accordance with the individual difference because there are individual differences depending on age and the like. The braking distance, the inter-vehicle distance at the time of a safe stop, and the rapid rear-end collision speed in FIGS. 10 to 12 are not necessarily the numerical values in the figures, but are preferably set optimally according to the vehicle type of the vehicle. The deceleration rate is 10% at the end of the free running distance.
Although the above is the case, it is desirable to set the optimum value depending on individual differences and vehicle types. The vehicle speed of the other vehicle is the own vehicle speed detection unit 2
It is easy to add or subtract the difference between the distance between the first vehicle and the second vehicle from the other vehicle to the vehicle speed detected in 5 divided by the time difference between the first measurement and the second measurement. You can ask. As for the display, the red LED etc. is slowly turned on in the normal safe state, the red LED etc. is flashed early at the time of the inter-vehicle warning, and the red LED etc. is flashed more quickly and sounded at the time of the rear-end collision warning. Is also good. It is more preferable that the parameters such as the vehicle speed at which the inter-vehicle warning and the rear-end collision warning are issued can be set separately according to individual differences.

In the case of obstacle judgment subroutine for obstacles in the case of rain (S71) as shown in the flow charts of FIGS. 13 and 14, since the road surface is slippery due to water, the process shown in FIG.
In the case where the vehicle is not raining (S71), the actual traveling state is corrected by multiplying the vehicle braking distance f2 (V2) from the time when the vehicle is braked to the time when the vehicle is stopped as shown in 2 (S72). ), The vehicle braking distance f2 (V2) is not corrected, and the distance Lc from the vehicle to the obstacle is measured (S7).
3). Then, when the deceleration of the own vehicle is 10% or more per second (S75), it is assumed that the vehicle is already decelerating, and the safety distance, which is a marginal distance with another vehicle when the vehicle is safely stopped as shown in FIG. Then, the safe inter-vehicle distance D can be obtained from D = f2 (V2) -d (S76), and the deceleration of the own vehicle is 10% per second.
If it is less than (S75), the driver has not yet noticed the existence of the obstacle and has not braked, so the free running distance, which is the distance that the vehicle travels from the human judgment until the body actually acts, is f3 (T). Then, the safe inter-vehicle distance D is D = f2 (V2
) + F3 (T) -d (S7)
7). At this time, if the distance Lc to the obstacle is equal to or greater than the safe inter-vehicle distance (S78), the safety warning display that the obstacle is within the safe inter-vehicle distance and the distance Lc to the obstacle are displayed (S79). When the distance Lc to the other vehicle is less than the safe inter-vehicle distance (S78), the own vehicle speed V2 is 6
When it is 0 km / h or more (S80), an indication that there is a possibility of a rear-end collision within the rapid rear-end collision distance and the distance Lc to the obstacle are displayed (S81), and the vehicle speed V2 is 60 km / h. If it is less than (S80), the display that there is an obstacle within the rear-end collision distance and the distance Lc to the obstacle are displayed (S82).

Therefore, the safe inter-vehicle distance is corrected according to the weather and whether or not the own vehicle is currently within the range of the safe inter-vehicle distance is displayed and the inter-vehicle distance with the obstacle is displayed. It is possible to reduce the dangerous driving of the vehicle and to display the degree of danger in the dangerous driving such as a rear-end collision depending on the speed of the own vehicle and issue an alarm, so that the driver can take measures according to the degree of the risk such as the rear-side collision in advance. Dangerous driving such as rear-end collision can be further reduced. Also,
When the deceleration rate was 10% or more, the end of the free running distance was set as
It is desirable to set the optimum value according to individual differences and vehicle types.

It should be noted that it is desirable to set the free-running distance to an optimum value in accordance with the individual difference because there are individual differences depending on age and the like. The braking distance and the inter-vehicle distance at the time of a safe stop in FIGS. 10 and 11 are not necessarily the numerical values in the figures, but are preferably set optimally according to the vehicle type of the vehicle. As for the display, the red LED etc. is slowly turned on in the normal safe state, the red LED etc. is flashed early at the time of the inter-vehicle warning, and the red LED etc. is flashed more quickly and sounded at the time of the rear-end collision warning. Is also good. Then, parameters such as the vehicle speed that issues the inter-vehicle warning and the rear-end collision warning are
It is even better if it can be set separately according to individual differences.

[0062]

As described above, the inter-vehicle distance measuring method of the present invention has the following effects.

1. This method can know the arrangement of the measured object around the road by measuring the unevenness of the distance from the vehicle to the measured object for each measured irradiation angle, so the measured object can be measured from this arrangement. Any of a small obstacle that may hinder the running of the vehicle, a large obstacle that hinders the running of the vehicle, and a road auxiliary equipment installed along a road that does not hinder the running of the vehicle. Since it is determined by the type, it is possible to reduce erroneous measurement of the distance from the vehicle to the object to be measured.

2. This method can accurately determine that the object to be measured is an obstacle such as an obstacle that will prevent the vehicle from traveling and a road auxiliary equipment such as a guardrail that does not hinder the vehicle running. It is possible to reduce erroneous measurement of the distance measurement.

3. When the distance from your vehicle to another vehicle is smaller than the inter-vehicle distance that allows you to stop without hitting another vehicle, this method displays that there is another vehicle at a distance where there is a risk of another collision and gives an alarm. Since the distance to the vehicle is displayed, it is possible to prevent the risk of a rear-end collision with another vehicle.

4. In this method, the distance from the vehicle to the obstacle stops without hitting the obstacle by presetting the distance that can stop without collision according to the distance from the vehicle to the obstacle. If the distance is smaller than the available vehicle distance, an obstacle is displayed at a distance where there is a danger of collision and an alarm is issued, and the distance from the vehicle to the obstacle is displayed. can do.

5. If the distance from your vehicle to another vehicle is smaller than the inter-vehicle distance that allows you to stop without hitting another vehicle, this method will display that there is another vehicle at a distance where there is a risk of another collision and give an alarm. Since the distance from the vehicle to the other vehicle is displayed, it is possible to prevent the risk of a rear-end collision with the other vehicle.
In addition, this method does not collide with the obstacle from the distance from the vehicle to the obstacle by setting in advance the distance at which the vehicle can stop without colliding according to the distance from the vehicle to the obstacle. If the distance is smaller than the distance you can stop at,
Since the presence of an obstacle is displayed at a distance where there is a danger of collision and an alarm is issued and the distance from the vehicle to the obstacle is displayed, the danger of collision with the obstacle can be prevented.

6. This method is based on the distance from the own vehicle to another vehicle that can be stopped without a rear-end collision, so that the distance from the own vehicle to another vehicle can be stopped without a rear-end collision. If the distance is smaller than the distance, the degree of danger of the own vehicle colliding with another vehicle is displayed according to the magnitude of the speed difference between the own vehicle and the other vehicle, an alarm is issued, and the distance from the own vehicle to the other vehicle is displayed. Therefore, the driver can deal with the risk of a rear-end collision with another vehicle, and dangerous driving such as a rear-end collision can be further reduced.

7. This method is based on the distance from the host vehicle to the obstacle, and the distance between the host vehicle and the obstacle can be stopped without hitting the obstacle. If the distance is smaller than the distance, the degree of danger of the vehicle colliding with an obstacle is displayed according to the speed of the vehicle and an alarm is issued, and the distance from the vehicle to the obstacle is displayed. The driver can deal with it according to the degree of, and dangerous driving such as a rear-end collision can be further reduced.

8. This method corrects the inter-vehicle distance that the vehicle can stop without hitting another vehicle due to the weather, and if the distance from the own vehicle to the other vehicle is smaller than the corrected inter-vehicle distance that can stop without another collision, Compensation for changes in braking distance due to weather by displaying the degree of danger that the vehicle will collide with another vehicle according to the size of the difference in speed of the other vehicle and issuing an alarm and displaying the distance from the vehicle to the other vehicle Therefore, the rear-end collision can be prevented without being influenced by the weather, and the driver can cope with the degree of risk of rear-end collision with another vehicle, thereby further reducing dangerous traveling such as rear-end collision.

9. This method presets the distance that can be stopped without collision according to the distance from the own vehicle to the above-mentioned obstacle, corrects the inter-vehicle distance that the vehicle can stop without hitting the obstacle depending on the weather, If the distance from the vehicle to the obstacle is smaller than the corrected inter-vehicle distance that can be stopped without a rear-end collision, the degree of danger that the own-vehicle collides with the obstacle according to the speed of the own-vehicle is displayed and an alarm is issued and By displaying the distance to the obstacle, the fluctuation of the braking distance due to the weather is also corrected, so the rear impact can be prevented without being affected by the weather, and the driver can deal with it according to the degree of risk of collision with the obstacle. Therefore, it is possible to reduce dangerous driving such as a rear-end collision.

10. If the distance from your vehicle to another vehicle is smaller than the inter-vehicle distance that allows you to stop without hitting another vehicle, this method causes your vehicle to collide with another vehicle according to the difference in speed between your vehicle and the other vehicle. The distance from the vehicle to the other vehicle is displayed as well as the warning is displayed and the driver can deal with it depending on the degree of danger of collision with another vehicle, further reducing dangerous driving such as rear collision. can do. Further, when the distance from the own vehicle to the obstacle is smaller than the inter-vehicle distance that can stop without hitting the obstacle, the degree of risk of the own vehicle hitting the obstacle according to the speed of the own vehicle. Is displayed and an alarm is issued, and the distance from the vehicle to the obstacle is displayed, so the driver can deal with the obstacle depending on the degree of risk of collision with the obstacle, and it is possible to further reduce dangerous driving such as collision. it can.

11. This method corrects the inter-vehicle distance that the vehicle can stop without hitting another vehicle due to the weather, and if the distance from the own vehicle to the other vehicle is smaller than the corrected inter-vehicle distance that can stop without another collision, Depending on the size of the difference in speed between other vehicles, the degree of danger that the own vehicle may collide with another vehicle is displayed and an alarm is issued. As it is corrected, the collision can be prevented without being affected by the weather, and the driver can deal with it according to the degree of danger of collision with another vehicle,
More dangerous driving such as a rear-end collision can be reduced. In addition, this method corrects the inter-vehicle distance that the vehicle can stop without hitting the above-mentioned obstacle due to the weather, and if the distance from the own vehicle to the obstacle is smaller than the corrected inter-vehicle distance that can stop without the collision. , By displaying the degree of danger that the vehicle will hit an obstacle according to the speed of the vehicle and issuing an alarm and displaying the distance from the vehicle to the obstacle, the fluctuation of the braking distance due to the weather is also corrected. It is possible to prevent a rear-end collision without being affected by the collision, and to deal with the driver according to the degree of danger of a rear-end collision with an obstacle, thereby further reducing dangerous driving such as a rear-end collision.

[Brief description of drawings]

FIG. 1 is a drawing for explaining a configuration of an apparatus used in an inter-vehicle distance measuring method that is an embodiment of the present invention.

FIG. 2 is a flowchart for explaining an inter-vehicle distance measuring method of the present invention.

FIG. 3 is a flowchart for explaining an inter-vehicle distance measuring method of the present invention.

FIG. 4 is a flowchart for explaining an obstacle determination subroutine of the vehicle distance measuring method of the present invention.

FIG. 5 is a diagram for explaining measurement of an obstacle by the inter-vehicle distance measuring method of the present invention.

FIG. 6 is a diagram for explaining the measurement of an obstacle by the inter-vehicle distance measuring method of the present invention.

FIG. 7 is a flowchart for explaining a risk determination subroutine of the inter-vehicle distance measuring method of the present invention.

FIG. 8 is a flow chart for explaining a vehicle-to-vehicle distance measuring method of the present invention, which is used for explaining another vehicle danger determination subroutine.

FIG. 9 is a flowchart for explaining a vehicle-to-vehicle distance measuring method of the present invention, which is a subroutine for determining a risk for another vehicle.

FIG. 10 is a diagram for explaining a braking distance with respect to the speed of the own vehicle or another vehicle in the vehicle-interval distance measuring method of the present invention.

FIG. 11 is a diagram for explaining an inter-vehicle distance at the time of a safe stop with respect to the speed of the own vehicle or another vehicle in the inter-vehicle distance measuring method of the present invention.

FIG. 12 is a view for explaining a rapid collision speed difference with respect to the speed of the own vehicle in the inter-vehicle distance measuring method of the present invention.

FIG. 13 is a flow chart for explaining a danger determination subroutine for fixed objects in the method for measuring an inter-vehicle distance according to the present invention.

FIG. 14 is a flow chart for explaining a danger determination subroutine for a fixed object in the method for measuring an inter-vehicle distance according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Light irradiation part, 3 ... Pulse drive part, 5 ... Light receiving part, 7 ...
Time / voltage conversion unit, 9 ... A / D conversion unit, 11 ... Arithmetic processing unit, 21 ... Irradiation plate drive unit, 23 ... Irradiation plate motor, 2
5 ... Own vehicle speed detection unit, 51 ... Display unit.

[Procedure amendment]

[Submission date] September 12, 1994

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 5

[Correction method] Change

[Correction content]

[Figure 5]

[Procedure Amendment 2]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 6

[Correction method] Change

[Correction content]

[Figure 6]

Claims (11)

[Claims] 1. An inter-vehicle distance measurement, which is mounted on a vehicle and measures a distance from the vehicle to the object to be measured based on a time from irradiation of light to reception of reflected light reflected by the object to be measured. In an inter-vehicle distance measuring method using a device, irradiating light to the object to be measured while changing an irradiation angle, receiving reflected light reflected by the object to be measured, and receiving the light from irradiation of the light. The distance from the vehicle to the measured object for each irradiation angle is measured based on the time until, and the measured object is measured by the unevenness of the distance from the vehicle to the measured object for each measured irradiation angle. To distinguish between a small obstacle that may obstruct traveling, a large obstacle that obstructs traveling of the vehicle, and a road auxiliary equipment installed along a road that does not obstruct traveling of the vehicle. Car characterized by Distance measuring method. 2. An inter-vehicle distance measurement, which is mounted on a vehicle and measures a distance from the vehicle to the object to be measured based on a time from irradiation of light to reception of reflected light reflected by the object to be measured. In an inter-vehicle distance measuring method using a device, irradiating light to the object to be measured while changing an irradiation angle, receiving reflected light reflected by the object to be measured, and receiving the light from the irradiation of the light. The distance from the vehicle to the DUT for each irradiation angle, and the corresponding irradiation measured this time from the distance from the vehicle to the DUT for each irradiation angle measured last time. The distance from the vehicle to the object to be measured for each angle is subtracted, and the difference between the subtracted distance for each irradiation angle and the travel distance of the vehicle from the previous measurement to the current measurement is compared, and the comparison is made. Less of the difference in distance If the difference between the distances in one direction is larger than the set value, the object to be measured is determined to be another vehicle traveling in front of the vehicle, and the object to be measured is not determined to be the other vehicle. It is determined that the object is a fixed object that is located on or near the road and does not move, and the measured object that is determined to be the fixed object has a difference in the distance in one or two directions among the difference in the compared distances. Is less than or equal to the set value, it is determined that the fixed object is a small obstacle that may interfere with the traveling of the vehicle, and the fixed object that is not determined to be the small obstacle is If the deviation does not fall within a certain range by autoregressing the distance to the measured object for each irradiation angle measured, it is determined that the fixed object is a large obstacle that interferes with the traveling of the vehicle, This time for the fixed object that is not distinguished as the small obstacle If the deviation is within a certain range by auto-regressing the distance to the object to be measured for each irradiation angle, the fixed object is determined to be a road auxiliary equipment that does not hinder the traveling of the vehicle. Inter-vehicle distance measurement method. 3. An inter-vehicle distance measurement, which is mounted on a vehicle and measures a distance from the vehicle to the object to be measured based on a time from irradiation of light to reception of reflected light reflected by the object to be measured. In an inter-vehicle distance measuring method using a device, irradiating light to the object to be measured while changing an irradiation angle, receiving reflected light reflected by the object to be measured, and receiving the light from irradiation of the light. The distance from the vehicle to the DUT for each irradiation angle, and the corresponding irradiation measured this time from the distance from the vehicle to the DUT for each irradiation angle measured last time. The distance from the vehicle to the object to be measured for each angle is subtracted, and the difference between the subtracted distance for each irradiation angle and the moving distance of the vehicle from the previous measurement to the current measurement is compared, and the comparison is made. Less of the difference in distance If the difference in the distance in one direction is larger than the set value, it is determined that the DUT is another vehicle traveling in front of the vehicle, and the distance from the vehicle to the other vehicle. Is smaller than the following distance that can be stopped without hitting another vehicle,
A method for measuring an inter-vehicle distance, which displays that the other vehicle is present at a distance where there is a danger of collision and issues an alarm, and also displays the distance from the vehicle to the other vehicle. 4. An inter-vehicle distance measurement which is mounted on a vehicle and measures a distance from the vehicle to the object to be measured based on a time from irradiation of light to reception of reflected light reflected by the object to be measured. In an inter-vehicle distance measuring method using a device, irradiating light to the object to be measured while changing an irradiation angle, receiving reflected light reflected by the object to be measured, and receiving the light from the irradiation of the light. The distance from the vehicle to the DUT for each irradiation angle, and the corresponding irradiation measured this time from the distance from the vehicle to the DUT for each irradiation angle measured last time. The distance from the vehicle to the object to be measured for each angle is subtracted, and the difference between the subtracted distance for each irradiation angle and the travel distance of the vehicle from the previous measurement to the current measurement is compared, and the comparison is made. Less of the difference in distance If the difference between the distances in one direction is larger than the set value, the object to be measured is determined to be another vehicle traveling in front of the vehicle, and the object to be measured is not determined to be the other vehicle. It is determined that the object is a fixed object that is located on or near the road and does not move, and the measured object that is determined to be the fixed object has a difference in the distance in one or two directions among the difference in the compared distances. Is less than or equal to the set value, it is determined that the fixed object is a small obstacle that may interfere with the traveling of the vehicle, and the fixed object that is not determined to be the small obstacle is If the deviation does not fall within a certain range by autoregressing the distance to the measured object for each irradiation angle measured, it is determined that the fixed object is a large obstacle that interferes with the traveling of the vehicle, The distance from the vehicle to the small obstacle or the large obstacle is When it is smaller than the inter-vehicle distance that can be stopped without colliding with the small obstacle or the large obstacle, while displaying a warning that there is the small obstacle or the large obstacle at a distance where there is a danger of colliding, and issuing an alarm, A method for measuring an inter-vehicle distance, characterized in that a distance from the vehicle to the small obstacle or the large obstacle is displayed. 5. An inter-vehicle distance measurement which is mounted on a vehicle and measures a distance from the vehicle to the object to be measured based on a time from irradiation of light to reception of reflected light reflected by the object to be measured. In an inter-vehicle distance measuring method using a device, irradiating light to the object to be measured while changing an irradiation angle, receiving reflected light reflected by the object to be measured, and receiving the light from the irradiation of the light. The distance from the vehicle to the DUT for each irradiation angle, and the corresponding irradiation measured this time from the distance from the vehicle to the DUT for each irradiation angle measured last time. The distance from the vehicle to the object to be measured for each angle is subtracted, and the difference between the subtracted distance for each irradiation angle and the travel distance of the vehicle from the previous measurement to the current measurement is compared, and the comparison is made. Less of the difference in distance If the difference in the distance in one direction is larger than the set value, it is determined that the DUT is another vehicle traveling in front of the vehicle, and the distance from the vehicle to the other vehicle. Is smaller than the following distance that can be stopped without hitting another vehicle,
On the road, the object to be measured that is not discriminated from the other vehicle is displayed on the road while indicating that the other vehicle is present at a distance where there is a danger of collision and displaying an alarm. Alternatively, it is determined that the fixed object is located near the road and does not move, and the difference in the distance in one or two directions is set to the measured object that is determined to be the fixed object, among the difference in the compared distances. If the value is less than or equal to the value, it is determined that the fixed object is a small obstacle that may interfere with the traveling of the vehicle, and the irradiation angle measured this time is determined for the fixed object that is not determined to be the small obstacle. If the deviation does not fall within a certain range by auto-regressing the distance to the object to be measured for each, the fixed object is determined to be a large obstacle that interferes with the traveling of the vehicle, and the vehicle to the The distance to a small obstacle or the large obstacle When it is smaller than the inter-vehicle distance that can be stopped without colliding with the small obstacle or the large obstacle, while displaying a warning that there is the small obstacle or the large obstacle at a distance where there is a danger of colliding, and issuing an alarm, A method for measuring an inter-vehicle distance, characterized in that a distance from the vehicle to the small obstacle or the large obstacle is displayed. 6. An inter-vehicle distance measurement which is mounted on a vehicle and measures a distance from the vehicle to the object to be measured based on a time from irradiation of light to reception of reflected light reflected by the object to be measured. In an inter-vehicle distance measuring method using a device, irradiating light to the object to be measured while changing an irradiation angle, receiving reflected light reflected by the object to be measured, and receiving the light from irradiation of the light. The distance from the vehicle to the DUT for each irradiation angle, and the corresponding irradiation measured this time from the distance from the vehicle to the DUT for each irradiation angle measured last time. The distance from the vehicle to the object to be measured for each angle is subtracted, and the difference between the subtracted distance for each irradiation angle and the moving distance of the vehicle from the previous measurement to the current measurement is compared, and the comparison is made. Less of the difference in distance If the difference in the distance in one direction is larger than the set value, it is determined that the DUT is another vehicle traveling in front of the vehicle, and the distance from the vehicle to the other vehicle. Is smaller than the following distance that can be stopped without hitting another vehicle,
The degree of danger of the vehicle colliding with the other vehicle is displayed and an alarm is issued according to the magnitude of the difference in speed between the vehicle and the other vehicle, and the distance from the vehicle to the other vehicle is displayed. An inter-vehicle distance measuring method characterized in that 7. An inter-vehicle distance measurement which is mounted on a vehicle and measures a distance from the vehicle to the object to be measured based on a time from irradiation of light to reception of reflected light reflected by the object to be measured. In an inter-vehicle distance measuring method using a device, irradiating light to the object to be measured while changing an irradiation angle, receiving reflected light reflected by the object to be measured, and receiving the light from the irradiation of the light. The distance from the vehicle to the DUT for each irradiation angle, and the corresponding irradiation measured this time from the distance from the vehicle to the DUT for each irradiation angle measured last time. The distance from the vehicle to the object to be measured for each angle is subtracted, and the difference between the subtracted distance for each irradiation angle and the travel distance of the vehicle from the previous measurement to the current measurement is compared, and the comparison is made. Less of the difference in distance If the difference between the distances in one direction is larger than the set value, the object to be measured is determined to be another vehicle traveling in front of the vehicle, and the object to be measured is not determined to be the other vehicle. It is determined that the object is a fixed object that is located on or near the road and does not move, and the measured object that is determined to be the fixed object has a difference in the distance in one or two directions among the difference in the compared distances. Is less than or equal to the set value, it is determined that the fixed object is a small obstacle that may interfere with the traveling of the vehicle, and the fixed object that is not determined to be the small obstacle is If the deviation does not fall within a certain range by autoregressing the distance to the measured object for each irradiation angle measured, it is determined that the fixed object is a large obstacle that interferes with the traveling of the vehicle, The distance from the vehicle to the small obstacle or the large obstacle is When the distance is smaller than the inter-vehicle distance that can stop without hitting the small obstacle or the large obstacle, the degree of risk of the vehicle hitting the small obstacle or the large obstacle according to the speed of the vehicle Is displayed and an alarm is issued, and the distance from the vehicle to the small obstacle or the large obstacle is displayed. 8. An inter-vehicle distance measurement which is mounted on a vehicle and measures a distance from the vehicle to the object to be measured based on a time from irradiation of light to reception of reflected light reflected by the object to be measured. In an inter-vehicle distance measuring method using a device, irradiating light to the object to be measured while changing an irradiation angle, receiving reflected light reflected by the object to be measured, and receiving the light from the irradiation of the light. The distance from the vehicle to the DUT for each irradiation angle, and the corresponding irradiation measured this time from the distance from the vehicle to the DUT for each irradiation angle measured last time. The distance from the vehicle to the object to be measured for each angle is subtracted, and the difference between the subtracted distance for each irradiation angle and the travel distance of the vehicle from the previous measurement to the current measurement is compared, and the comparison is made. Less of the difference in distance If the difference between the distances in one direction is larger than the set value, it is determined that the DUT is another vehicle traveling in front of the vehicle, and the vehicle becomes the other vehicle depending on the weather. Correct the inter-vehicle distance that can be stopped without a rear-end collision, and if the distance from the vehicle to the other vehicle is smaller than the corrected inter-vehicle distance that can be stopped without a rear-end collision, the difference in speed between the vehicle and the other vehicle A method for measuring an inter-vehicle distance, which displays a degree of danger of the vehicle colliding with the other vehicle according to a size, issues an alarm, and displays a distance from the vehicle to the other vehicle. 9. An inter-vehicle distance measurement, which is mounted on a vehicle and measures a distance from the vehicle to the object to be measured based on a time from irradiation of light to reception of reflected light reflected by the object to be measured. In an inter-vehicle distance measuring method using a device, irradiating light to the object to be measured while changing an irradiation angle, receiving reflected light reflected by the object to be measured, and receiving the light from the irradiation of the light. The distance from the vehicle to the DUT for each irradiation angle, and the corresponding irradiation measured this time from the distance from the vehicle to the DUT for each irradiation angle measured last time. The distance from the vehicle to the object to be measured for each angle is subtracted, and the difference between the subtracted distance for each irradiation angle and the travel distance of the vehicle from the previous measurement to the current measurement is compared, and the comparison is made. Less of the difference in distance If the difference between the distances in one direction is larger than the set value, the object to be measured is determined to be another vehicle traveling in front of the vehicle, and the object to be measured is not determined to be the other vehicle. It is determined that the object is a fixed object that is located on or near the road and does not move, and the measured object that is determined to be the fixed object has a difference in the distance in one or two directions among the difference in the compared distances. Is less than or equal to the set value, it is determined that the fixed object is a small obstacle that may interfere with the traveling of the vehicle, and the fixed object that is not determined to be the small obstacle is If the deviation does not fall within a certain range by autoregressing the distance to the measured object for each irradiation angle measured, it is determined that the fixed object is a large obstacle that interferes with the traveling of the vehicle, Depending on the weather, the vehicle may follow the small obstacle or the large obstacle. Correct the inter-vehicle distance that can be stopped without collision, if the distance from the vehicle to the small obstacle or the large obstacle is smaller than the corrected inter-vehicle distance that can be stopped without additional collision, according to the speed of the vehicle An inter-vehicle distance characterized by displaying the degree of danger of a vehicle colliding with the small obstacle or the large obstacle and issuing an alarm, and displaying the distance from the vehicle to the small obstacle or the large obstacle. Measuring method. 10. An inter-vehicle distance measurement, which is mounted on a vehicle and measures a distance from the vehicle to the object to be measured based on a time from irradiation of light to reception of reflected light reflected by the object to be measured. In an inter-vehicle distance measuring method using a device, irradiating light to the object to be measured while changing an irradiation angle, receiving reflected light reflected by the object to be measured, and receiving the light from the irradiation of the light. The distance from the vehicle to the DUT for each irradiation angle, and the corresponding irradiation measured this time from the distance from the vehicle to the DUT for each irradiation angle measured last time. The distance from the vehicle to the object to be measured for each angle is subtracted, and the difference between the subtracted distance for each irradiation angle and the travel distance of the vehicle from the previous measurement to the current measurement is compared, and the comparison is made. Of the differences in distance, If the difference in distance in at least one direction is larger than the set value, it is determined that the DUT is another vehicle traveling in front of the vehicle, and the distance from the vehicle to the other vehicle is determined. If the distance is smaller than the following distance that can be stopped without hitting another vehicle,
It displays the degree of danger of the vehicle colliding with the other vehicle according to the magnitude of the difference in speed between the vehicle and the other vehicle and issues an alarm, and displays the distance from the vehicle to the other vehicle. , The object to be measured that is not distinguished from the other vehicle is a fixed object that is located on or near the road and does not move, and the difference in the compared distance with respect to the object to be measured that is determined to be the fixed object. If the difference between the distances in one or two directions is less than or equal to the set value, it is determined that the fixed object is a small obstacle that may interfere with the traveling of the vehicle, and the small obstacle is detected. If the deviation does not fall within a certain range by auto-regressing the distance to the measured object for each irradiation angle measured this time for the fixed object that is not determined as, the fixed object interferes with the traveling of the vehicle. It is determined that the obstacle is a large obstacle, If the distance from the vehicle to the small obstacle or the large obstacle is smaller than the inter-vehicle distance at which the vehicle can stop without hitting the small obstacle or the large obstacle, the vehicle has the small obstacle according to the speed of the vehicle. An inter-vehicle distance measuring method, which displays a degree of danger of a rear-end collision with an object or the large obstacle and issues an alarm, and displays a distance from the vehicle to the small obstacle or the large obstacle. 11. An inter-vehicle distance measurement, which is mounted on a vehicle and measures a distance from the vehicle to the object to be measured based on a time from irradiation of light to reception of reflected light reflected by the object to be measured. In an inter-vehicle distance measuring method using a device, irradiating light to the object to be measured while changing an irradiation angle, receiving reflected light reflected by the object to be measured, and receiving the light from irradiation of the light. The distance from the vehicle to the DUT for each irradiation angle, and the corresponding irradiation measured this time from the distance from the vehicle to the DUT for each irradiation angle measured last time. The distance from the vehicle to the object to be measured for each angle is subtracted, and the difference between the subtracted distance for each irradiation angle and the travel distance of the vehicle from the previous measurement to the current measurement is compared, and the comparison is made. Of the differences in distance, If the difference in the distances in at least one direction is larger than the set value, it is determined that the DUT is another vehicle traveling in front of the vehicle, and the vehicle is different from the other vehicle depending on the weather. If the inter-vehicle distance that can be stopped without a rear-end collision is corrected, and the distance from the vehicle to the other vehicle is smaller than the corrected inter-vehicle distance that can be stopped without a rear-end collision, the difference between the speeds of the vehicle and the other vehicle The degree of danger that the vehicle will collide with the other vehicle according to the size of the warning, and gives an alarm, and displays the distance from the vehicle to the other vehicle, and the measured object is not distinguished from the other vehicle. It is determined that the object is a fixed object that is located on or near the road and does not move, and the measured object that is determined to be the fixed object has a difference in the distance in one or two directions among the difference in the compared distances. Is less than or equal to the set value In the case of, the fixed object is determined to be a small obstacle that may interfere with the traveling of the vehicle, and the fixed object that is not determined to be the small obstacle is determined for each irradiation angle measured this time. When the distance to the object to be measured self-regresses and the deviation does not fall within a certain range, it is determined that the fixed object is a large obstacle that interferes with the running of the vehicle, and the vehicle is Correct the inter-vehicle distance that can stop without hitting a small obstacle or a large obstacle, and the distance from the vehicle to the small obstacle or the large obstacle can stop without hitting the small obstacle or the large obstacle If the distance is smaller than the inter-vehicle distance, the degree of danger of the vehicle colliding with the small obstacle or the large obstacle according to the speed of the vehicle is displayed and an alarm is issued, and the small obstacle or the large obstacle is output from the vehicle. Obstacle Inter-vehicle distance measuring method characterized by displaying the distance to the object.