JP4100956B2 - Follow-up traveling device and control method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
This invention detects an inter-vehicle distance from a preceding vehicle traveling in the same lane as the own vehicle, derives a target inter-vehicle distance according to the own vehicle speed, and controls acceleration / deceleration means to make the inter-vehicle distance the target inter-vehicle distance. The present invention relates to a follow-up traveling device that follows a preceding vehicle while holding the same and a control method thereof.
[0002]
[Prior art]
Conventionally, a follow-up traveling device such as an inter-vehicle distance control type constant-speed traveling device mounted as an auxiliary for safe driving of an automobile has conventionally been, for example, 60 m when the own vehicle speed is 60 km / h, and 100 m when the own vehicle speed is 100 km / h. The target vehicle distance is determined according to the vehicle speed of the vehicle, and the vehicle ahead of the vehicle travels in the same lane as the vehicle based on the detection result of the vehicle distance from the vehicle traveling in front of the vehicle by the vehicle distance detection means comprising the vehicle distance sensor. If it is determined whether the vehicle is a preceding vehicle, and it is determined that the vehicle is a preceding vehicle, control is performed to maintain the inter-vehicle distance with the preceding vehicle at the target inter-vehicle distance.
[0003]
At this time, the target acceleration / deceleration is derived from the inter-vehicle distance by the inter-vehicle distance sensor and the relative speed between the host vehicle and the preceding vehicle, and when the target acceleration / deceleration satisfies a certain condition, the throttle valve is opened to accelerate, Alternatively, the vehicle is decelerated by operating a so-called automatic brake such as closing the throttle valve or forcibly operating the brake.
[0004]
In particular, when the preceding vehicle decelerates and the inter-vehicle distance decreases, the own vehicle needs to respond quickly to the deceleration of the preceding vehicle, so the acceleration / deceleration (in this case, the deceleration) of the preceding vehicle is controlled by the control law. Incorporation has been done in the past.
[0005]
Specifically, the inter-vehicle distance detected by the inter-vehicle distance sensor is time-differentiated, the relative speed with the preceding vehicle is obtained from the differentiation result, and further this is time-differentiated to calculate the relative acceleration / deceleration of the preceding vehicle. In addition to the speed and the difference between the target inter-vehicle distance and the actual inter-vehicle distance, the target acceleration / deceleration of the vehicle is obtained by a feedback control law that takes into account the relative acceleration / deceleration, and the automatic brake is activated according to the obtained target acceleration / deceleration. There is a method of slowing down.
[0006]
Also, when preventing rear-end collision, the feed-forward control law is a control that makes the preceding vehicle and the host vehicle have the same speed at the target distance, that is, the square of the relative speed is calculated as the difference between the target inter-vehicle distance and the actual inter-vehicle distance. There is a technique in which a relative acceleration / deceleration is added to a value divided by the difference to obtain a target acceleration / deceleration of the host vehicle, and an automatic brake is operated to decelerate according to the obtained target acceleration / deceleration.
[0007]
[Problems to be solved by the invention]
However, with these methods, since the relative acceleration obtained by differentiating the inter-vehicle distance is further differentiated to obtain the relative acceleration / deceleration of the preceding vehicle, it contains noise components and the estimation accuracy is insufficient. There is a problem in that the accuracy of the target acceleration / deceleration is reduced.
[0008]
In addition, it is conceivable to suppress noise by filtering the relative acceleration / deceleration required in this way, but there is a disadvantage that the response is newly lowered.
[0009]
SUMMARY OF THE INVENTION An object of the present invention is to provide a follow-up traveling device capable of maintaining a predetermined inter-vehicle distance by following a high-accuracy response to a deceleration of a preceding vehicle and a control method therefor.
[0010]
[Means for Solving the Problems]
In order to achieve the above-described object, the follow-up traveling device according to the present invention detects an inter-vehicle distance from a preceding vehicle traveling in the same lane as the own vehicle, derives a target inter-vehicle distance according to the own vehicle speed, and accelerates / decelerates. In the follow-up traveling device that follows the preceding vehicle while controlling the acceleration / deceleration means to maintain the inter-vehicle distance at the target inter-vehicle distance, the determining unit estimates the acceleration / deceleration of the preceding vehicle by using a Kalman filter. When the sign of the estimated error, which is the difference between the estimated inter-vehicle distance after a predetermined time derived from the estimated acceleration / deceleration and the actually detected inter-vehicle distance, continues, and the cumulative sum of the estimated error is a predetermined When the vehicle is determined to be in the first state that is the estimated delay state when the vehicle is greater than the value, the sign of the estimated error is determined from the first state when the vehicle is determined to be in the first state. When is reversed Alternatively, when the cumulative sum of the estimation errors becomes smaller than the predetermined value, it is determined that the host vehicle is in the second state that has escaped from the first state, and the control means determines the first state by the determination means. When it is determined that the vehicle is in a state, the acceleration / deceleration means is operated in accordance with the target vehicle acceleration / deceleration calculated based on the relative speed of the preceding vehicle, the difference between the target inter-vehicle distance and the inter-vehicle distance, and the estimated acceleration / deceleration of the preceding vehicle. On the other hand, when it is determined by the determining means that the first state is exited and the second state is determined, the relative speed of the preceding vehicle, the distance difference between the target inter-vehicle distance and the inter-vehicle distance, Escape from the first state Just before Remembered The estimated acceleration / deceleration of the preceding vehicle Multiplied by a constant The acceleration / deceleration means is controlled in accordance with a target acceleration / deceleration of the host vehicle calculated based on the value (claim 1).
[0011]
According to such a configuration, when the host vehicle estimates and follows the acceleration / deceleration of the preceding vehicle, when the host vehicle is determined to be in the first state that is an estimated delay state associated with a change in the acceleration / deceleration of the preceding vehicle, The acceleration / deceleration means is controlled according to the target vehicle acceleration / deceleration calculated based on the relative speed of the preceding vehicle, the distance difference between the target inter-vehicle distance and the detected inter-vehicle distance, and the estimated acceleration of the preceding vehicle, while the own vehicle is in an estimated delay state ( When it is determined that the second state is out of the first state, the relative speed of the preceding vehicle, the distance difference between the target inter-vehicle distance and the inter-vehicle distance, Escape from the first state Just before Remembered The estimated acceleration / deceleration of the preceding vehicle Multiplied by a constant Since the acceleration / deceleration means is controlled in accordance with the target acceleration / deceleration of the own vehicle calculated based on the value, the auto-acceleration / deceleration means is particularly responsive to the deceleration of the preceding vehicle so that the predetermined distance between the vehicles can be maintained with high responsiveness and high accuracy. You can slow down the car.
[0012]
Further, the following traveling device according to the present invention includes an inter-vehicle distance detecting unit that detects an inter-vehicle distance between the own vehicle and the preceding vehicle, a vehicle speed detecting unit that detects the own vehicle speed, an inter-vehicle distance detected by the inter-vehicle distance detecting unit, and The relative speed deriving means for deriving the relative speed of the preceding vehicle from the detection speed by the vehicle speed detecting means, the detected inter-vehicle distance by the inter-vehicle distance detecting means and the detected speed by the vehicle speed detecting means, using the Kalman filter, An estimated acceleration / deceleration deriving means for estimating an acceleration / deceleration and deriving an estimated acceleration / deceleration; and deriving an estimated inter-vehicle distance after a predetermined time from the estimated acceleration / deceleration by the estimated acceleration / deceleration deriving means; An estimation error deriving unit that derives an estimation error that is a difference from the detected inter-vehicle distance, and the determination unit includes successive signs of the estimation error. And when the cumulative sum of the estimation errors is larger than a predetermined value, the first determination means for determining that the vehicle is in the first state, and from the first state, Second judging means for judging that the vehicle is in the second state that has left the first state when the sign is reversed or when the cumulative sum of the estimation errors becomes smaller than the predetermined value; When the control means determines that the host vehicle is in the first state by the first determination means, the relative speed by the relative speed deriving means, the target inter-vehicle distance, and the detected inter-vehicle distance The target acceleration / deceleration of the own vehicle is calculated by calculation based on the difference between the distance to the estimated acceleration / deceleration and the estimated acceleration / deceleration by the estimated acceleration / deceleration means, and the second determining means determines that the own vehicle is in the second state. When said relative speed and Serial distance difference and Escape from the first state Just before Remembered The estimated acceleration / deceleration of the preceding vehicle Multiplied by a constant A target acceleration / deceleration calculating means for calculating a target acceleration / deceleration of the own vehicle by an operation based on the value, and when the first determining means determines that the own vehicle is in the first state, the relative speed and the The acceleration / deceleration unit is controlled according to a target acceleration / deceleration based on a calculation based on a distance difference and the estimated acceleration / deceleration, and the second determination unit determines that the own vehicle has left the first state and is in the second state. Sometimes the relative speed and the distance difference Take off the first state Just before Remembered The estimated acceleration / deceleration of the preceding vehicle Multiplied by a constant The acceleration / deceleration means is controlled in accordance with a target acceleration / deceleration based on a calculation based on the value (claim 2).
[0013]
According to such a configuration, when the first determination unit determines that the host vehicle is in the first state in the estimated delay state, the target acceleration / deceleration calculation unit detects the relative speed of the preceding vehicle, the target inter-vehicle distance, and the like. The target acceleration / deceleration of the host vehicle is calculated by a calculation based on the distance difference from the inter-vehicle distance and the estimated acceleration / deceleration of the preceding vehicle, and the acceleration / deceleration means is controlled by the control means in accordance with the calculated target acceleration / deceleration. On the other hand, when the second determination means determines that the host vehicle is in the second state that has left the estimated delay state (first state), the target acceleration / deceleration calculation means detects the relative speed of the preceding vehicle, the target inter-vehicle distance, and the like. The distance difference from the inter-vehicle distance, Escape from the first state Just before Remembered The estimated acceleration / deceleration of the preceding vehicle Multiplied by a constant The target acceleration / deceleration of the host vehicle is calculated by calculation based on the value, and the acceleration / deceleration means is controlled by the control means according to the calculated target acceleration / deceleration.
[0014]
Therefore, the vehicle is in an estimated delay state In the first state Sometimes Calculated based on the relative speed of the preceding vehicle, the difference between the target inter-vehicle distance and the detected inter-vehicle distance, and the estimated acceleration / deceleration of the preceding vehicle By calculating the target acceleration / deceleration of the host vehicle, the responsiveness can be improved. In particular, the predetermined distance between the vehicles can be maintained by following the deceleration of the preceding vehicle with good responsiveness and high accuracy. You can decelerate your vehicle.
[0015]
Further, when the host vehicle is in the second state where it has left the estimated delay state (first state), the relative speed of the preceding vehicle, the distance difference between the target inter-vehicle distance and the detected inter-vehicle distance, Escape from the first state Just before Remembered The estimated acceleration / deceleration of the preceding vehicle Multiplied by a constant By calculating the target acceleration / deceleration of the vehicle based on the value, it is possible to follow the deceleration of the preceding vehicle without causing a so-called overshoot, and it is possible to realize stable tracking.
[0016]
In the follow-up traveling device according to the present invention, the absolute value of the acceleration / deceleration of the preceding vehicle derived from the relative speed of the preceding vehicle by the relative speed deriving unit is smaller than a predetermined value. Third control means for determining whether the absolute value of the acceleration / deceleration is smaller than the specified value by the third determination means, the target acceleration / deceleration calculation means, The target acceleration / deceleration is calculated by calculation based on the relative speed and the distance difference, and the acceleration / deceleration means is controlled according to the target acceleration / deceleration (Claim 3).
[0017]
According to such a configuration, when the absolute value of the acceleration / deceleration of the preceding vehicle is smaller than the specified value by the third determining means, it can be determined that the preceding vehicle has escaped the acceleration state, so the relative speed, the target inter-vehicle distance, By calculating the target acceleration / deceleration by calculation based on the distance difference from the detected inter-vehicle distance, the speed of the host vehicle can be quickly controlled to the same speed as the preceding vehicle.
[0019]
In addition, the control method of the following traveling device according to the present invention detects the inter-vehicle distance from the preceding vehicle traveling in the same lane as the own vehicle, derives the target inter-vehicle distance according to the own vehicle speed, and accelerates / decelerates the acceleration / deceleration means. In a control method of a follow-up traveling device that controls and follows the preceding vehicle while maintaining the inter-vehicle distance at the target inter-vehicle distance, the detected inter-vehicle distance and vehicle speed detected by the inter-vehicle distance detecting means and the preceding vehicle The relative speed of the preceding vehicle is derived from the detected speed of the host vehicle detected by the detecting means, and the estimated acceleration / deceleration is derived by estimating the acceleration / deceleration of the preceding vehicle using a Kalman filter, from the estimated acceleration / deceleration Deriving an estimated inter-vehicle distance after a predetermined time and deriving an estimation error that is a difference between the estimated inter-vehicle distance and the actual detected inter-vehicle distance, and when the sign of the estimation error continues, and When it is determined that the vehicle is in the first state, which is an estimated delay state associated with a change in acceleration / deceleration of the preceding vehicle, and when the sum of products is greater than a predetermined value, In addition, when the sign of the estimation error is reversed from the first state, or when the cumulative sum of the estimation error is smaller than the predetermined value, the vehicle has left the first state. In the second state When When the vehicle is determined to be in the first state, the relative speed of the preceding vehicle, the difference between the target inter-vehicle distance and the detected inter-vehicle distance, and the estimated preceding vehicle to be estimated are estimated. By calculating based on the acceleration / deceleration, the target acceleration / deceleration of the own vehicle is calculated, and the acceleration / deceleration means is controlled according to the calculated target acceleration / deceleration, and the own vehicle leaves the first state and is in the second state. The relative speed and the distance difference Take off the first state Just before Remembered The estimated acceleration / deceleration of the preceding vehicle Multiplied by a constant The target acceleration / deceleration of the host vehicle is calculated by calculation based on the value, and the acceleration / deceleration means is controlled in accordance with the calculated target acceleration / deceleration (claim 4).
[0020]
According to such a configuration, when the host vehicle is determined to be in the first state, which is an estimated delay state associated with the change in acceleration / deceleration of the preceding vehicle, the relative speed of the preceding vehicle, the target inter-vehicle distance, and the detected inter-vehicle distance The target acceleration / deceleration of the own vehicle is calculated by calculation based on the distance difference and the estimated acceleration / deceleration of the preceding vehicle, and the acceleration / deceleration means is controlled according to the calculated target acceleration / deceleration, while the own vehicle is in the estimated delay state (first If it is determined that the second state has escaped from (1 state), the relative speed of the preceding vehicle, the distance difference between the target inter-vehicle distance and the detected inter-vehicle distance, Escape from the first state Just before Remembered The estimated acceleration / deceleration of the preceding vehicle Multiplied by a constant The target acceleration / deceleration of the host vehicle is calculated by calculation based on the value, and the acceleration / deceleration means is controlled according to the calculated target acceleration / deceleration.
[0021]
Therefore, the vehicle is in an estimated delay state In the first state Sometimes By calculation based on the relative speed of the preceding vehicle, the distance difference between the target inter-vehicle distance and the detected inter-vehicle distance, and the estimated acceleration / deceleration of the preceding vehicle By calculating the target acceleration / deceleration, the responsiveness can be improved. In particular, the host vehicle is maintained so as to keep a predetermined distance between the vehicles following the deceleration of the preceding vehicle with high responsiveness and high accuracy. You can slow down.
[0022]
In addition, the vehicle is in an estimated delay state (First state) Took off In the second state Sometimes Of the preceding car The relative speed, the difference between the target inter-vehicle distance and the detected inter-vehicle distance, Estimated acceleration / deceleration value of the preceding vehicle By calculating the target acceleration / deceleration based on the above, it is possible to follow the deceleration of the preceding vehicle without causing so-called overshoot, and it is possible to realize stable follow-up.
[0023]
Further, the control method of the following traveling device according to the present invention determines whether an absolute value of acceleration / deceleration of the preceding vehicle derived from the relative speed of the preceding vehicle is smaller than a predetermined specified value, When it is determined that the absolute value of acceleration / deceleration is smaller than the specified value, the target acceleration / deceleration is calculated by calculation based on the relative speed and the distance difference, and the acceleration / deceleration means is controlled according to the target acceleration / deceleration. (Claims) 5 ).
[0024]
According to such a configuration, when the absolute value of the acceleration / deceleration of the preceding vehicle is smaller than the specified value, it can be determined that the preceding vehicle has escaped the acceleration state, so the relative speed, the distance between the target inter-vehicle distance and the detected inter-vehicle distance. By calculating the target acceleration / deceleration by calculation based on the difference, the speed of the own vehicle can be quickly controlled to the same speed as the preceding vehicle.
[0026]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will be described with reference to FIGS. 1 is a block diagram, FIG. 2 is a flowchart for explaining operations, and FIGS. 3 and 4 are diagrams for explaining operations.
[0027]
As shown in FIG. 1, an inter-vehicle distance between the host vehicle and a preceding vehicle is detected by an inter-vehicle distance sensor 1 composed of a scan laser radar as an inter-vehicle distance detection means. At this time, the inter-vehicle distance sensor 1 is irradiated with laser light in front of the own vehicle from the semiconductor laser of the scan laser radar as described above, and is scanned in a horizontal direction by a predetermined angle (for example, 0.1 °) and reflected therefrom. The distance between the vehicle and the preceding vehicle traveling in the same lane is detected from the time from when the light is received by the light receiver until the reflected light is received. Such inter-vehicle distance detection is periodically repeated every short time of about 100 ms.
[0028]
In addition, a vehicle speed sensor 2 is provided as vehicle speed detection means for detecting the host vehicle speed, and various switches 3 including a setting switch and a release switch for follow-up running control are also provided. Signals from these sensors 1 and 2 and various switches 3 are taken in by an electronic control unit (hereinafter referred to as ECU) 5, and each part is controlled by the ECU 5.
[0029]
Specifically, the ECU 5 determines whether or not the preceding vehicle is a preceding vehicle traveling in the same lane as the own vehicle, based on the detection result of the inter-vehicle distance from the vehicle traveling in front of the own vehicle by the inter-vehicle distance sensor 1. If it is determined that the vehicle is a preceding vehicle, based on the detected inter-vehicle distance detected by the inter-vehicle distance sensor 1 and the own vehicle speed by the vehicle speed sensor 2, the target inter-vehicle distance corresponding to the own vehicle speed and the preceding vehicle In addition to deriving the relative speed ΔV with respect to the vehicle, the Kalman filter is used to estimate the acceleration / deceleration of the preceding vehicle to derive the estimated acceleration / deceleration α, and the estimated inter-vehicle distance after a predetermined time is derived from the estimated acceleration / deceleration α Then, an estimation error which is a difference between the estimated inter-vehicle distance and the actual inter-vehicle distance is derived.
[0030]
Then, based on the relative speed ΔV, the distance difference ΔD between the target inter-vehicle distance and the detected inter-vehicle distance, and the estimated acceleration / deceleration α, the target acceleration / deceleration Gr of the own vehicle is calculated, and the acceleration / deceleration means is performed according to the calculated target acceleration / deceleration Gr. Control of the electronic throttle 7 and the brake actuator 8, that is, control of the opening degree of the electronic throttle 7 and drive control of the brake actuator 8 are performed. Such a derivation process of the relative speed ΔV by the ECU 5 corresponds to the relative speed derivation means in the present invention, the derivation process of the estimated acceleration / deceleration α corresponds to the estimated acceleration / deceleration derivation means, and the estimation error derivation process is the estimation error derivation process. The target acceleration / deceleration Gr calculation process corresponds to the target acceleration / deceleration calculation means.
[0031]
By the way, in calculating the target acceleration / deceleration Gr, the ECU 5 determines whether the own vehicle is a preceding vehicle based on whether the sign of the estimation error continues and whether the cumulative sum of the estimation error is larger than a predetermined value. It is determined whether or not the estimated delay state (hereinafter referred to as the first state) due to a change in acceleration / deceleration of the vehicle is detected, and whether the sign of the estimation error is reversed from the first state (estimated delay state) Whether or not the vehicle has exited the first state and has shifted to the second state is determined based on whether or not the cumulative sum of the estimation errors has become equal to or less than a predetermined value.
[0032]
Further, the ECU 5 determines whether or not the preceding vehicle is in the third state where the preceding vehicle has left the acceleration state based on whether or not the absolute value of the estimated acceleration / deceleration α of the preceding vehicle is smaller than a predetermined value. As described above, the determination processing for determining whether the ECU 5 is in the first state, the second state, or the third state corresponds to the first determination unit, the second determination unit, and the third determination unit in the present invention, respectively. .
[0033]
When the ECU 5 determines that the host vehicle is in the first state (estimated delay state), the target acceleration / deceleration of the host vehicle is determined based on the relative speed ΔV of the preceding vehicle, the distance difference ΔD, and the estimated acceleration / deceleration α. Gr
Gr = ΔV * K1 + ΔD * K2 + α * K3 (1)
It is calculated by the calculation of the following formula. Here, K1, K2, and K3 are constants.
[0034]
Further, when the ECU 5 determines that the vehicle has exited the first state (estimated delay state) and has shifted to the second state, the ECU 5 determines the target acceleration / deceleration Gr of the vehicle based on the relative speed ΔV and the distance difference ΔD. ,
Gr = ΔV * K1 + ΔD * K2 + A (2)
It is calculated by the calculation of the following formula. Here, A stored (α * K3), which is the preceding preceding vehicle deceleration component. value Used.
[0035]
Further, when the ECU 5 determines that the preceding vehicle is in the third state where it has escaped from the acceleration state, the ECU 5 determines the target acceleration / deceleration Gr of the vehicle based on the relative speed ΔV and the distance difference ΔD.
Gr = ΔV * K1 + ΔD * K2 (3)
It is calculated by the calculation of the following formula.
[0036]
Thus, the ECU 5 calculates the target acceleration / deceleration Gr of the own vehicle by the calculation of the equations (1) to (3) corresponding to the first to third states, and the electronic throttle 7 and the brake according to the calculated target acceleration / deceleration Gr. The actuator 8 is controlled. Such control processing by the ECU 5 corresponds to control means. In addition, as shown in FIG. 1, an alarm unit 9 comprising an alarm buzzer, an alarm lamp, an LCD for displaying a predetermined message, or a combination thereof is provided, and the inter-vehicle distance is closer than the target inter-vehicle distance. In the case where too much is performed, the ECU 5 controls the notifying unit 9, and the notifying unit 9 is activated to issue a warning to the driver.
[0037]
Next, the operation for deriving the target acceleration / deceleration Gr will be described with reference to the flowchart of FIG. As shown in FIG. 2, the ECU 5 derives the speed and acceleration / deceleration of the preceding vehicle using a Kalman filter (S1), derives the estimated inter-vehicle distance from the estimated speed / acceleration, and detects the estimated inter-vehicle distance and the actual detection. An estimation error that is a difference from the inter-vehicle distance is derived (S2).
[0038]
Then, based on whether the sign of the estimation error continues and whether the cumulative sum of the estimation errors is equal to or greater than a predetermined value, the ECU 5 causes the vehicle to change with the acceleration / deceleration of the preceding vehicle. It is determined whether or not the vehicle is in the 1 state (estimated delay state) (S3). If the determination result is YES, the target acceleration / deceleration Gr is calculated by the calculation of the above equation (1) (S4), and the operation Ends.
[0039]
On the other hand, if the determination result in step S3 is NO, the ECU 5 determines whether the sign of the estimation error has been reversed or whether the cumulative sum of the estimation errors has become equal to or less than a predetermined value. A determination is made as to whether or not the state has been changed to the second state (S5), and if the determination result is YES, the target acceleration / deceleration Gr is calculated by the calculation of equation (2) (S6). The operation ends.
[0040]
Furthermore, if the determination result in step S5 is NO, the ECU 5 causes the third vehicle in which the preceding vehicle has left the acceleration state based on whether or not the absolute value of the estimated acceleration / deceleration α of the preceding vehicle is smaller than a predetermined specified value. It is determined whether or not the vehicle is in a state (S7). If the determination result is YES, the target acceleration / deceleration Gr is calculated by the calculation of the above-described equation (3) (S8), and then the operation is terminated. If the determination result in S7 is NO, the operation ends as it is.
[0041]
Thus, when the ECU 5 determines that the host vehicle is in the estimated delay state, the target acceleration / deceleration Gr of the host vehicle is calculated by the calculation of the equation (1) based on the relative speed ΔV, the distance difference ΔD, and the estimated acceleration / deceleration α. In accordance with the calculated target acceleration / deceleration Gr, the ECU 5 controls the electronic throttle 7 and the brake actuator 8 which are acceleration / deceleration means.
[0042]
On the other hand, when it is determined by the ECU 5 that the host vehicle has left the estimated delay state, the target acceleration / deceleration Gr of the host vehicle is calculated by the equation (2) based on the relative speed ΔV, the distance difference ΔD, and the immediately preceding stored value A. The electronic throttle 7 and the brake actuator 8 which are acceleration / deceleration means are controlled by the ECU 5 according to the calculated target acceleration / deceleration Gr.
[0043]
As a result, for example, when the acceleration / deceleration of the preceding vehicle changes as shown by the solid line in FIG. 3 (in this case, represents deceleration), the response is not received in the state 1 as in the conventional one-dot chain line in FIG. Delay, overshoot occurred in state 2, but in the first state and the second state, respectively, by the calculations of equations (1) and (2), and in the third state, by the calculation of equation (3), the target adjustment By calculating the speed Gr, as shown by the broken line in the figure, the responsiveness is improved in the first state, the overshoot is eliminated in the second state, and the speed of the own vehicle is quickly set to the preceding vehicle in the third state. Controlled to the same speed. Further, when the preceding vehicle accelerates or decelerates in a pattern as shown in FIG. 4, the same applies as in FIG. 3 and 4 indicate the first to third states.
[0044]
Therefore, according to the above-described embodiment, when the host vehicle is in the first state (estimated delay state), the target acceleration / deceleration Gr of the host vehicle is calculated by the calculation of the formula (1) in consideration of the estimated acceleration / deceleration α. Thus, the responsiveness can be improved, and in particular, the host vehicle can be decelerated so as to follow the deceleration of the preceding vehicle with high responsiveness and high accuracy and maintain a predetermined inter-vehicle distance.
[0045]
Further, when the host vehicle leaves the first state and shifts to the second state, the target acceleration / deceleration Gr of the host vehicle is calculated by the calculation of equation (2) based on the relative speed ΔV, the distance difference ΔD, and the immediately preceding stored value A. By doing so, it is possible to follow the deceleration of the preceding vehicle without causing so-called overshoot, and realizes stable tracking without the influence of noise as in the case of using the acceleration / deceleration by the second-order differential of the distance as in the past. can do.
[0046]
Further, the target acceleration / deceleration Gr of the own vehicle is calculated by the calculation of the equation (3) based on the relative speed ΔV and the distance difference ΔD, which is determined to be the third state in which the preceding vehicle has left the acceleration state. The speed can be controlled to the same speed as the preceding vehicle faster.
[0047]
In the above-described embodiment, when it is determined that the preceding vehicle is in the third state in which the acceleration state has left the acceleration state, the target acceleration / deceleration Gr of the host vehicle is calculated by the calculation of equation (3) based on the relative speed ΔV and the distance difference ΔD. Although the case where the calculation is performed has been described, it is not always necessary to determine whether or not the state is the third state.
[0048]
In the above-described embodiment, the case where the Kalman filter is used for estimating the acceleration / deceleration of the preceding vehicle has been described. However, the acceleration / deceleration of the preceding vehicle may be estimated using a state estimation method other than the Kalman filter. It is.
[0049]
Furthermore, in the above-described embodiment, the case where the inter-vehicle distance detection means is the inter-vehicle distance sensor 1 composed of a scan laser radar has been described, but the inter-vehicle distance detection means is not limited to such an inter-vehicle distance sensor 1. Of course.
[0050]
The present invention is not limited to the above-described embodiment, and various modifications other than those described above can be made without departing from the spirit of the present invention.
[0051]
【The invention's effect】
As described above, according to the first aspect of the invention, when the own vehicle estimates and follows the acceleration / deceleration of the preceding vehicle, the own vehicle is in the estimated delay state accompanying the change in the acceleration / deceleration of the preceding vehicle. In the first state, the acceleration / deceleration means is controlled according to the target acceleration / deceleration means calculated based on the relative speed of the preceding vehicle, the difference between the target inter-vehicle distance and the detected inter-vehicle distance, and the estimated acceleration of the preceding vehicle. Is determined to be the second state where the estimated delay state (first state) has been escaped, the relative speed of the preceding vehicle, the distance difference between the target inter-vehicle distance and the detected inter-vehicle distance, Escape from the first state Just before Remembered The estimated acceleration / deceleration of the preceding vehicle Multiplied by a constant Since the acceleration / deceleration means is controlled in accordance with the target acceleration / deceleration of the own vehicle calculated based on the value, the auto-acceleration / deceleration means is particularly responsive to the deceleration of the preceding vehicle so that the predetermined distance between the vehicles can be maintained with high responsiveness and high accuracy. It is possible to provide a follow-up traveling device that can decelerate the vehicle and that can decelerate the vehicle so as to follow the deceleration of the preceding vehicle with high responsiveness and high accuracy and maintain a predetermined inter-vehicle distance.
[0052]
Claim 2 4 According to the invention described in, the host vehicle is in an estimated delay state In the first state Sometimes The relative speed of the preceding vehicle, the distance difference between the target inter-vehicle distance and the detected inter-vehicle distance, Estimated acceleration / deceleration And based on By calculating the target acceleration / deceleration of the host vehicle, the responsiveness can be improved. In particular, the predetermined distance between the vehicles can be maintained by following the deceleration of the preceding vehicle with good responsiveness and high accuracy. It becomes possible to decelerate the vehicle.
[0053]
On the other hand, when the host vehicle is in the second state where the estimated delay state (first state) has been released, the relative speed of the preceding vehicle, the distance difference between the target vehicle distance and the detected vehicle distance Escape from the first state Just before Remembered The estimated acceleration / deceleration of the preceding vehicle Multiplied by a constant By calculating the target acceleration / deceleration of the own vehicle based on the value, it is possible to follow the deceleration of the preceding vehicle without causing a so-called overshoot, and it is possible to realize a stable follow-up.
[0054]
As a result, it is possible to provide a follow-up traveling device and a control method capable of maintaining a predetermined inter-vehicle distance by following a high-accuracy response to the deceleration of the preceding vehicle, and as an aid for safe traveling. It is effective for.
[0055]
Claim 3 5 According to the invention described in (4), when the absolute value of the acceleration / deceleration of the preceding vehicle is smaller than the specified value, it can be determined that the preceding vehicle has escaped the acceleration state. Therefore, the distance between the relative speed, the target inter-vehicle distance, and the detected inter-vehicle distance. By calculating the target acceleration / deceleration by calculation based on the difference, it becomes possible to control the speed of the own vehicle faster to the same speed as the preceding vehicle.
[Brief description of the drawings]
FIG. 1 is a block diagram of an embodiment of the present invention.
FIG. 2 is a flowchart for explaining the operation of the embodiment of the present invention.
FIG. 3 is an operation explanatory diagram of one embodiment of the present invention.
FIG. 4 is an operation explanatory diagram of one embodiment of the present invention.
[Explanation of symbols]
1 Inter-vehicle distance sensor (inter-vehicle distance detection means)
2 Vehicle speed sensor (vehicle speed detection means)
5 ECU (relative speed deriving means, estimated acceleration / deceleration deriving means, estimation error deriving means, target acceleration / deceleration calculating means, first to third determination means, control means)
7 Electronic throttle (acceleration / deceleration means)
8 Brake actuator (acceleration / deceleration means)

Claims (5)

The distance between the host vehicle and the preceding vehicle traveling in the same lane is detected, the target inter-vehicle distance is derived according to the host vehicle speed, and acceleration / deceleration control is performed to maintain the inter-vehicle distance at the target inter-vehicle distance. While in the following traveling device that follows the preceding vehicle,
The judging means estimates the acceleration / deceleration of the preceding vehicle using a Kalman filter, and the sign of an estimation error that is a difference between the estimated inter-vehicle distance after a predetermined time derived from the estimated estimated acceleration / deceleration and the actually detected inter-vehicle distance When the code is continuous, and when the cumulative sum of the estimation errors is larger than a predetermined value, the vehicle is determined to be in the first state in the estimated delay state, and is in the first state. When the vehicle is determined to be in the first state and the sign of the estimation error is reversed, or when the cumulative sum of the estimation errors becomes smaller than the predetermined value, the vehicle is moved to the first state. Judge that it is the second state that has left the state,
When the control means determines that the vehicle is in the first state, the control means calculates based on the relative speed of the preceding vehicle, the difference between the target inter-vehicle distance and the inter-vehicle distance, and the estimated acceleration / deceleration of the preceding vehicle. While the acceleration / deceleration means is controlled according to the target acceleration / deceleration of the vehicle, when the determination means determines that the second state is exited from the first state, the relative speed of the preceding vehicle, the target inter-vehicle distance, and the inter-vehicle distance The acceleration / deceleration means is controlled in accordance with a target acceleration / deceleration of the host vehicle calculated based on a distance difference from the distance and a value obtained by multiplying the estimated acceleration / deceleration of the preceding vehicle stored immediately before leaving the first state by a constant. Follow-up traveling device. An inter-vehicle distance detecting means for detecting an inter-vehicle distance between the own vehicle and the preceding vehicle;
Vehicle speed detecting means for detecting the own vehicle speed;
Relative speed deriving means for deriving the relative speed of the preceding vehicle from the detected inter-vehicle distance detected by the inter-vehicle distance detecting means and the detected speed detected by the vehicle speed detecting means;
Estimated acceleration / deceleration deriving means for deriving an estimated acceleration / deceleration by estimating the acceleration / deceleration of the preceding vehicle using a Kalman filter from the detected inter-vehicle distance detected by the inter-vehicle distance detecting means and the detected speed detected by the vehicle speed detecting means;
An estimation error deriving means for deriving an estimated inter-vehicle distance after a predetermined time from the estimated acceleration / deceleration by the estimated acceleration / deceleration deriving means, and deriving an estimation error that is a difference between the estimated inter-vehicle distance and the actual detected inter-vehicle distance; With
The determination means is
First determination means for determining that the vehicle is in the first state when the sign of the estimation error is continuous and when the cumulative sum of the estimation errors is greater than a predetermined value;
The second state in which the vehicle has left the first state when the sign of the estimation error is reversed from the first state, or when the cumulative sum of the estimation errors is smaller than the predetermined value. Second judging means for judging that
The control means is
When the first determining means determines that the host vehicle is in the first state, the relative speed by the relative speed deriving means, a distance difference between the target inter-vehicle distance and the detected inter-vehicle distance, and the estimation The target acceleration / deceleration of the host vehicle is calculated by calculation based on the estimated acceleration / deceleration by the acceleration / deceleration deriving unit, and the relative speed is determined when the second determining unit determines that the host vehicle is in the second state. And a target acceleration / deceleration calculating means for calculating a target acceleration / deceleration of the host vehicle by a calculation based on the distance difference and a value obtained by multiplying the estimated acceleration / deceleration of the preceding vehicle stored immediately before leaving the first state by a constant. ,
When the first determination unit determines that the host vehicle is in the first state, the acceleration / deceleration unit is controlled according to a target acceleration / deceleration according to a calculation based on the relative speed, the distance difference, and the estimated acceleration / deceleration.
When it is determined by the second determination means that the vehicle has left the first state and is in the second state, the relative speed, the distance difference, and the preceding vehicle stored immediately before leaving the first state are stored. The follow-up traveling device according to claim 1, wherein the acceleration / deceleration unit is controlled according to a target acceleration / deceleration based on a calculation based on a value obtained by multiplying the estimated acceleration / deceleration by a constant . The determination means comprises third determination means for determining whether an absolute value of acceleration / deceleration of the preceding vehicle derived from the relative speed of the preceding vehicle by the relative speed deriving device is smaller than a predetermined specified value. ,
When the absolute value of the acceleration / deceleration is determined to be smaller than the specified value by the third determination unit, the control unit performs an operation based on the relative speed and the distance difference by the target acceleration / deceleration calculation unit. The follow-up traveling device according to claim 2, wherein the target acceleration / deceleration is calculated and the acceleration / deceleration means is controlled according to the target acceleration / deceleration. The distance between the host vehicle and the preceding vehicle traveling in the same lane is detected, the target inter-vehicle distance is derived according to the host vehicle speed, and acceleration / deceleration control is performed to maintain the inter-vehicle distance at the target inter-vehicle distance. While, in the control method of the following traveling device that follows the preceding vehicle,
The relative speed of the preceding vehicle is derived from the detected inter-vehicle distance detected by the inter-vehicle distance detection means and the preceding vehicle and the detected speed of the own vehicle detected by the vehicle speed detection means, and the Kalman filter is used to derive the relative speed. Estimate the acceleration / deceleration of the preceding vehicle to derive the estimated acceleration / deceleration,
Deriving an estimated intervehicular distance after a predetermined time from the estimated acceleration / deceleration and deriving an estimation error that is a difference between the estimated intervehicular distance and the actual detected intervehicular distance;
When the sign of the estimation error is continuous, and when the cumulative sum of the estimation errors is greater than a predetermined value, the vehicle is in an estimated delay state associated with a change in acceleration / deceleration of the preceding vehicle. When the vehicle is determined to be in the first state and the vehicle is determined to be in the first state, if the sign of the estimation error is reversed from the first state, or the cumulative sum of the estimation errors is the predetermined value if it becomes smaller, it is determined that the Ru second state der the vehicle has emerged from the first state,
When it is determined that the host vehicle is in the first state, the relative speed of the preceding vehicle, the distance difference between the target inter-vehicle distance and the detected inter-vehicle distance, and the estimated acceleration / deceleration of the estimated preceding vehicle And calculating the target acceleration / deceleration of the vehicle by controlling the acceleration / deceleration means according to the calculated target acceleration / deceleration.
When it is determined that the host vehicle has exited the first state and is in the second state, a constant is set for the estimated acceleration / deceleration of the preceding vehicle stored immediately before the relative speed, the distance difference, and the first state are exited. A method for controlling a follow-up traveling device, comprising: calculating a target acceleration / deceleration of an own vehicle by an operation based on a multiplied value and controlling the acceleration / deceleration means according to the calculated target acceleration / deceleration. Determining whether an absolute value of acceleration / deceleration of the preceding vehicle derived from the relative speed of the preceding vehicle is smaller than a predetermined value,
When it is determined that the absolute value of the acceleration / deceleration is smaller than the specified value, the target acceleration / deceleration is calculated by calculation based on the relative speed and the distance difference, and the acceleration / deceleration means is controlled according to the target acceleration / deceleration. The control method of the following traveling apparatus of Claim 4 characterized by the above-mentioned.

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