JP4106582B2 - Vehicle detection device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to drift adjustment of a detection device including a radar and a yaw rate sensor mounted on a vehicle.
[0002]
[Prior art]
In recent years, a four-wheeled vehicle may be provided with a monitoring function for a preceding vehicle and a follow-up traveling function for the preceding vehicle in order to improve driving ease and safety. In addition, in order to improve the stability when the vehicle is running (for example, prevention of side slipping, etc.), the vehicle steering system, braking system, or engine system may be changed depending on the situation as a four-wheel steering system (so-called 4WS). There is a case in which a function (hereinafter referred to as a vehicle motion control function) for positively and automatically controlling is provided. Such advanced functions include a radar or a camera (front object detection means) for detecting a preceding vehicle or the like, a yaw rate sensor for detecting a lateral behavior (for example, yaw rate) of the host vehicle (horizontal Directional behavior detection means) is required. In addition, the sensor for detecting the behavior in the lateral direction is necessary for grasping the state of the lateral slip of the own vehicle. For the purpose of grasping information such as the preceding vehicle, the state of the road surface on which the own vehicle is traveling ( This sensor is also useful for reliably detecting the curvature of the road surface (whether it is a straight road or the like).
[0003]
By the way, naturally, the above-described radar, yaw rate sensor, and the like need to properly adjust the zero point (in the case of radar, the center axis position of the detection area). The control function (preceding vehicle following control, etc.) cannot be satisfactorily realized. In particular, a yaw rate sensor or the like has a property that a zero point drifts with the passage of time (that is, there is a drift with time), and therefore, it is necessary to perform drift adjustment periodically at short intervals if possible. In addition, it can be said that the center axis of the detection area may not be slightly deviated physically from the proper position due to vehicle vibration, etc., and it is necessary to grasp the amount of movement (drift component) from time to time. It is desirable to adjust accordingly.
[0004]
As a technique for adjusting the drift of a yaw rate sensor mounted on a vehicle, a method for adjusting a zero point while the vehicle is stopped is described in, for example, Japanese Patent Laid-Open No. 57-200143. This stores the output of the yaw rate sensor while the vehicle is stopped (the actual yaw rate is zero) as a drift component, and corrects the output of the running yaw rate sensor (adds or subtracts the drift component).
Further, for example, in Japanese Patent Laid-Open No. 5-314397, a straight running state (actual yaw rate is zero) is determined using a steering angle sensor, and a straight running state is determined (the steering angle is substantially equal). In the same manner, a method for adjusting the zero point of the yaw rate sensor is disclosed.
Further, for example, in Japanese Patent Laid-Open No. 11-23606, a straight running state is determined using a wheel speed sensor, and the same is true when a straight running state is determined (when the left and right wheel speed difference is substantially zero). Discloses a method for adjusting a zero point of a yaw rate sensor.
[0005]
On the other hand, as a method of adjusting the radar zero point (the center axis position of the detection area), a reference reflector for axis adjustment is installed in front of the stopped vehicle, and detection is performed based on the position measurement result of this reference reflector. Various techniques for adjusting the position of the area have been proposed.
Further, as a method of automatically performing radar axis adjustment during traveling, there is a method disclosed in, for example, Japanese Patent Application Laid-Open No. 11-142520. This is because only the data of the preceding vehicle (radar detection data) collected when the host vehicle and the preceding vehicle are traveling straight on the same line is extracted as valid data. The internal parameters are set and changed so that the center position of the detection area matches the average center position of the preceding vehicle obtained by statistical processing of the steering angle sensor or yaw rate to determine the straight running state. An embodiment using a sensor is illustrated.
[0006]
[Problems to be solved by the invention]
However, the conventional adjustment methods such as the radar and the yaw rate sensor described above have the following problems.
First, the zero point adjustment using a yaw rate sensor or the like while the vehicle is stopped is possible to adjust the zero point accurately when the vehicle stops. Since point adjustment becomes impossible for a long time, it is not sufficient in practice. That is, when the vehicle travels on a highway for a long time, the zero point adjustment is not performed for a long time, and the lateral behavior of the vehicle cannot be detected sufficiently accurately due to a drift with time or the like generated during this time.
Therefore, it is necessary to adjust the zero point while the vehicle is running, such as a yaw rate sensor. However, the conventional method using the steering angle sensor and the wheel speed sensor as described above has a problem that high-precision adjustment cannot be performed because of cost. there were. This is because a very expensive steering angle sensor or wheel speed sensor is required to more accurately determine the straight traveling state of the vehicle for the zero point adjustment. The steering angle sensor is usually installed in a vehicle as a component of the power steering system, but a sensor that can grasp the steering direction and the like is generally used. In order to use it, it is necessary to change it to a particularly high precision one. In addition, the wheel speed sensor is installed only in a luxury vehicle equipped with, for example, a traction control system, and even if it is conventionally mounted on a vehicle, the vehicle speed sensor is similar to the steering angle sensor. It was not highly accurate so that the straight running state could be judged more accurately.
[0007]
Also, the method of adjusting the axis of a radar or the like by stopping the vehicle and using a reference reflector is generally only performed at the time of shipment or periodic inspection at a vehicle production factory or repair shop, so during the vehicle running When an axis deviation occurs, for example, the axis deviation remains uncorrected for a long time until the next periodic inspection.
Therefore, the detection means such as a radar preferably needs to be adjusted while the vehicle is running, but as described above, the straight running state is determined by the steering angle sensor and the yaw rate sensor, and is obtained in this straight running state. In the method of adjusting the axis during traveling based on the data of the preceding vehicle, there is a possibility that accurate adjustment cannot be performed. This is because, based on information from a steering angle sensor that is not very accurate or a yaw rate sensor that has drifted in the zero point, data collected in a state that is not actually in a straight running state may be used for axis adjustment. It is.
[0008]
Therefore, the present invention is a vehicle detection device including a forward object detection means such as a radar, and a lateral behavior detection means such as a yaw rate sensor, and does not require other detection means (particularly expensive sensors) It is an object of the present invention to provide a vehicular detection device that can adjust the drift of a specific detection means (particularly, a lateral behavior detection means) more accurately and inexpensively.
[0009]
[Means for Solving the Problems]
A vehicle detection apparatus according to the present invention includes a forward object detection means for detecting at least position information of an object in front of the vehicle, a lateral behavior detection means for detecting lateral behavior information of the vehicle, A vehicle detection device having a vehicle speed detection means for detecting a traveling speed,
The vehicle includes a traveling adjustment unit that executes at least a drift adjustment process of the lateral behavior detection unit based on information detected by each detection unit during traveling of the vehicle.
Here, the “drift adjustment process” sets or updates a correction value that is added to or subtracted from the output data, for example, so that a deviation (drift component) from the appropriate value of the output of the detection unit is corrected. It is processing.
The present invention is particularly effective when a yaw rate sensor for detecting the yaw rate of the vehicle is used as the lateral behavior detecting means. This is because the yaw rate sensor generally has the property that the zero point drifts with time.
[0010]
In a preferred aspect of the present invention, the lateral behavior detection means is a yaw rate sensor for detecting the yaw rate of the vehicle as the behavior information, and the drift adjustment processing of the yaw rate sensor is executed while the vehicle is stopped. Adjustment means are provided.
In addition, another preferable aspect of the present invention is that, when the running adjustment unit is within a specified time from the point in time when the vehicle starts running from a stopped state, the drifting drift of the detection unit is less If there is no drift detection processing of the detection means (generally, the forward object detection means, for example, radar), and the elapsed time exceeds a specified time, the detection means having a drift with time is detected. Means (generally, the lateral behavior detecting means, for example, the yaw rate sensor) performs drift adjustment processing.
[0011]
As specific examples of the drift adjustment processing, the distance (Y) to the object detected by the front object detection means, the relative speed (Vx) in the lateral direction of the object, and the relative speed in the front-rear direction of the object (Vy), vehicle speed (V) detected by the vehicle speed detection means, and lateral behavior information (for example, yaw rate Yaw) of the vehicle detected by the lateral behavior detection means, the drift of each detection means A moving amount corresponding to the composite value of the components (for example, a deviation angle θ or a value of θ · V / Y described later) is obtained, and information on the front object detecting means or the lateral behavior detecting means is obtained by the obtained moving amount value. Some of them are set to correct the value of.
Alternatively, when the presence of a stop object is recognized in front of the vehicle based on the information detected by the front object detection unit and the vehicle speed detection unit, the distance to the stop object detected by the front object detection unit ( Y), the lateral relative speed (Vx) of the stationary object, the vehicle speed (V) detected by the vehicle speed detecting means, and the lateral behavior information of the vehicle detected by the lateral behavior detecting means ( For example, a movement amount (for example, a deviation angle θ or a value of θ · V / Y described later) corresponding to a combined value of drift components of each detection unit is obtained from the yaw rate Yaw), and only the obtained movement amount value is obtained. It may be set so as to correct the information value of the front object detection means or the lateral behavior detection means.
In addition, the aspect which calculates | requires and averages the value of the said movement amount is preferable.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an example of an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram for explaining the apparatus configuration and the like of this example, in which FIG. 1A is a block diagram showing an apparatus configuration including a radar and the like, and FIG. 1B is a diagram showing a radar detection area and the like. FIG. 1C is a diagram for explaining the relationship of each data for obtaining the drift component. What is indicated by reference numeral 1 in FIG. 1A is a radar (in this case, specifically, a laser radar). Reference numeral 21 denotes a yaw rate sensor, and reference numeral 31 denotes a vehicle speed sensor (vehicle speed detection means).
In addition, the utilization form in the vehicle of the information obtained by these detection means (radar 1, yaw rate sensor 21, vehicle speed sensor 31) is not particularly limited, and any form may be used. In any case, it can be effectively used to realize advanced functions such as the preceding vehicle monitoring function, the preceding vehicle following control, or the vehicle motion control function.
Moreover, although each detection means may be comprised as a separate unit, two or more of each detection means may be comprised as the same unit goods. Further, for example, the laser radar 1 and the yaw rate sensor 21 are manufactured as a single unit (for example, an optional part or a commercially available product), and are retrofitted to the vehicle according to a user's request (that is, attached after being shipped from the production factory). But you can. Since the output system of the vehicle speed sensor 31 that is generally standard equipment for any vehicle can be easily taken out and connected, such a unit product is mounted on the vehicle by the user himself, and FIG. It is not impossible to construct the configuration of a).
[0013]
The radar 1 includes a scanning unit 11, an LD (laser diode) 12, a drive circuit 13, a scanning position detection unit 14, a PD (photodiode) 15, a signal processing unit 16, and a control circuit 17 (adjustment means and stop during traveling according to the present invention). Equivalent to a medium adjusting means). For example, a portion including the LD 12, the scanning unit 11, and the PD 15 described above constitutes a detection head of the radar 1.
Here, the scanning device 11 scans the laser beam output from the LD 12 at a predetermined angle in the left-right direction with a reflection mirror that is driven to oscillate, and irradiates a predetermined scanning area in front of the vehicle. 17 is operated at a predetermined timing and cycle.
The drive circuit 13 is a circuit that is controlled by the control circuit 17 and operates the LD 12 at each light emission timing created by the control circuit 17 to output laser light. Note that the light emission timing here is set in advance according to the scanning resolution. If the frequency is high, the scanning resolution generally increases.
The scanning position detection device 14 is an element that detects the scanning direction of the scanning device 11 and inputs the signal (scan direction signal) to the control circuit 17.
The PD 15 receives reflected light returned from the irradiated laser beam reflected by the detection target at a sampling period corresponding to the issue timing, and an electric signal corresponding to the received light amount (hereinafter referred to as a received light amount signal). The received light amount signal output from the PD 15 is input to the control circuit 17 via the signal processing unit 16.
[0014]
The control circuit 17 is constituted by a microcomputer (hereinafter referred to as a microcomputer) composed of, for example, a CPU, a ROM, a RAM, and the like, and basically performs a distance measurement operation by the following control process during normal operation of the apparatus.
That is, while controlling the scanning device 11 and the drive circuit 13 as described above, the distance (measurement distance) from the propagation delay time T from light emission to light reception to the detection target is calculated, and the detection target is determined from the scanning direction at that time. The direction is determined, and the amount of received light is determined based on the intensity of the received light (the magnitude of the received light amount signal). From these data (distance, direction, received light amount), the detection target is identified and moved as described later. The status is determined, and detection data including type information, position information, size information, etc. of the detection target is output.
[0015]
As illustrated in FIG. 2B, the angle region (scan area) where the laser beam is actually irradiated is more than the angle region (detection area) where the reflected data is received and the above-described distance data is measured. By changing the setting position (software parameter) for data processing within the scan area of this detection area (actually within the detection allowable area with a margin), the optical head of the apparatus A certain amount of position adjustment (that is, axis adjustment) in the left-right direction of the detection area is possible without physically changing the mounting position.
It should be noted that the entire scan area and detection area can be changed by changing the setting value (control parameter) in the control process of the operation range (for example, the operation range of the scanning motor) of the scanning unit 11 that realizes scanning. A configuration in which the position is adjusted to some extent in the scanning direction can also be adopted.
In addition, such adjustment by changing the parameter is hereinafter referred to as soft optical axis adjustment, and by this soft optical axis adjustment, a range in which the center position of the detection area can be adjusted in the horizontal direction (scanning direction). Hereinafter, it is referred to as a soft optical axis adjustable range.
[0016]
Next, the operation of the radar 1 will be described. First, the operation (ranging operation) during normal operation as a laser radar will be described.
The LD 12 operates under the control of the drive circuit 13 for each light emission timing produced by the control circuit 17 and outputs laser light. Then, the laser beam from the LD 12 is scanned by the scanning device 11 and irradiated to a scan area wider than the detection area as illustrated in FIG.
When the irradiated laser light is reflected back to the detection target, the reflected light is received by the PD 15, and the received light amount signal is input to the control circuit 17 via the signal processing unit 16. The control circuit 17 first generates the aforementioned data (distance, direction, received light amount) from the received light amount signal and the scanning direction signal input from the scanning position detecting device 14.
This data (distance, direction, received light amount) is generated every time light emission and light reception are performed in the detection area as illustrated in FIG. 1B. Eventually, the detection processing of the radar 1 is performed in the detection area. This is performed only for an object to be detected.
[0017]
The control circuit 17 performs the following processing based on the data (distance, direction, received light amount) and the speed data V of the host vehicle input from the vehicle speed sensor 31 in a predetermined cycle (in this case, the laser beam is scanned). (Period).
That is, first, the distance to the object and the direction data (polar coordinate data) are converted into X and Y coordinates (Cartesian coordinate data) and stored in a memory (not shown) for each region together with the received light amount data. Here, each region is a region set in advance by dividing the detection area into, for example, equal divisions.
[0018]
Next, based on the distance data in the memory converted into the Cartesian coordinate system and registered for each region, the data is grouped to extract the target object, and the laser emission unit of the grouped target object The distance in the X direction (for example, the left-right direction) and the Y direction (for example, the front-rear direction) and the width dimension are calculated.
Here, the grouping is a process of collecting adjacent data that are close to each other in the individual data of each region and making it one object. Specifically, for example, windows (areas on the Cartesian coordinate system) having a certain width are provided for each data in the front-rear direction and the left-right direction, and the other data included in this window are grouped together. Note that the data grouped in this way (hereinafter referred to as group data) is handled collectively as one object in the subsequent processing.
[0019]
Next, the object detected during the previous scan is associated with the object detected during the current scan, and the relative speed of the detected object is further calculated.
That is, a fixed window is set around the position where the group data is estimated to appear during the current scan from the previous group data position and its relative speed. Then, it is determined whether or not the current group data is in this window, and if it is within this range, the previous group data and the current group data are handled as being for the same object. In addition, relative speeds Vx (left-right direction) and Vy (front-back direction) are calculated from the movement distances.
Next, stop object discrimination of the object is performed based on the relative speed of the object.
That is, by comparing the relative speed Vy of the target object with the speed V of the host vehicle (speed detected by the vehicle speed sensor 31), it is determined whether the target object is stopped or moving. That is, for example, when the vehicle speed V and the relative speed Vy are substantially equal, it is determined that the vehicle is a stopped object.
[0020]
Next, based on the determination result, for example, a preceding vehicle that is a target of a front obstacle monitoring system or a follow-up traveling control system is specified. Information (position data, relative speed data, etc.) relating to the identified preceding vehicle and the like is sequentially transmitted to the control means of the front obstacle monitoring system and the follow-up traveling control system, and used for operation control of these systems. .
[0021]
Next, the drift adjustment process executed by the control circuit 17 will be described.
First, the drift adjustment while stopped will be described. For example, the control circuit 17 repeatedly executes the process shown in FIG. 2A while the detection apparatus is being activated. That is, for example, based on the output value of the vehicle speed sensor 31, it is determined whether or not the vehicle is stopped (step S1). If the vehicle is stopped, the zero point of the yaw rate sensor 21 is adjusted (step S2). This zero point adjustment is performed as follows, for example. That is, the output of the yaw rate sensor 21 while the vehicle is stopped (the actual yaw rate is zero) is updated and stored as a drift component, and the subsequent output of the yaw rate sensor is corrected using this drift component as a correction value (the drift component is added). Or subtract). Thereby, at least immediately after the vehicle is stopped and the drift adjustment is executed, the output (after correction) of the yaw rate sensor becomes extremely accurate with no drift component.
[0022]
Next, drift adjustment during traveling will be described. When the vehicle is in a traveling state and the radar 1 is in operation, the control circuit 17 repeatedly executes the process shown in FIG.
That is, first, in step S11, it is determined whether or not a stationary object has been observed by the ranging operation of the radar 1, and if it has been observed, the process proceeds to step S12, and if not, this step S11 is repeated.
Next, in step S12, it is determined whether or not the width of the observed stop (the size in the left-right direction) is equal to or smaller than a predetermined value (for example, 40 cm). Then, the process returns to step S11. Since a stationary object having a large width is partially detected and the apparent center of gravity fluctuates, an error in the detection data of the relative speed Vx in the lateral direction may increase. Therefore, such a large stationary object is detected. This is to avoid adopting data. The distance that can be detected by this laser radar is about 100 m, and if it is about 40 cm in front of 100 m, it is the resolution margin of this laser radar, and the accuracy is maximized. Moreover, as such a stop | stop object of a magnitude | size, the reflector (reflector) etc. in a roadside belt | band | zone correspond.
Next, in step S13, it is determined whether or not the vehicle speed V is equal to or higher than a predetermined value (for example, 60 km / hr). If the vehicle speed V is equal to or higher than the predetermined value, the process proceeds to step S14. This is because when the vehicle speed V is small, an error in the value of the deviation angle θ (movement amount) calculated in step S16 described later increases.
[0023]
In step S14, the shift angle θ (θ = α−β) is used as data corresponding to the drift component of the present detection device (the amount of movement that is the combined value of the drift components of the detection means), and the equation (4) described later. To find and memorize.
That is, the relationship among the relative speeds Vx (left-right direction) and Vy (front-rear direction) of the stationary object, the distance Y to the stationary object, and the curvature radius R of the traveling route of the own vehicle is as shown in FIG. The angles α and β in FIG. 1C are naturally equal if there is no measurement error (ie, mainly a drift component) of each detection means. For this reason, the shift angle θ, which is the difference between the angles α and β, corresponds to the combined value of the drift component of each detection means. If the yaw rate of the vehicle is Yaw, the following equation (1) is established.
Yaw = V ÷ R (1)
In general, since R is sufficiently large with respect to Y and Vy is sufficiently large with respect to Vx, the following approximate expressions (2) and (3) are established.
α ≒ Y ÷ R (2)
β ≒ Vx ÷ Vy (3)
Moreover, since it is a stop object, Vy = V. Therefore, the shift angle θ can be calculated by the following equation (4).
θ = (Y · Yaw−Vx) ÷ V (4)
In addition, it is good also as an aspect which calculates accurately using a trigonometric function, without using approximate expressions like said Formula (2) and (3).
[0024]
As the values of the distance Y and the relative velocity Vx to be substituted into the equation (4), values obtained from the detection data of the radar 1 for the stationary object determined to be observed in step S11 are used. Further, as the yaw rate Yaw, a value read from the output of the yaw rate sensor 21 when observing the stationary object is used. Further, as the vehicle speed V, a value read from the output of the vehicle speed sensor 31 at the time of observing the stationary object is used.
Further, the deviation angle θ obtained in this way should always be substantially zero if there is no measurement error including drift components in all of the detection means (radar 1, yaw rate sensor 21, vehicle speed sensor 31). . Further, since the vehicle speed sensor 31 among the detection means uses the number of rotations of the tire, the measurement error is extremely small compared with other detection means and can be ignored. Further, the optical axis deviation of the radar 1 rarely occurs unless there is a special case such as a large acceleration applied to the vehicle (that is, the radar 1 has no drift over time). Therefore, the value of the deviation angle θ corresponds to the drift component (optical axis movement amount) of the radar 1 and the drift component of the yaw rate sensor 21. In addition, in most cases, the drift with time of the yaw rate sensor 21 is mainly used. It depends on the ingredients.
[0025]
Next, in step S15, it is determined whether or not the value of the deviation angle θ newly obtained by the calculation in step S14 has reached a specified number (for example, 100), and if it has reached, the process proceeds to step S16. If there is, the process returns to step S11.
In step S16, an average value of the newly determined number of deviation angles θ is obtained.
Next, in step S17, it is determined whether or not the elapsed time since the vehicle started from the stop state is within a specified time (for example, within 10 minutes), and if it is within the specified time, the process proceeds to step S18 and must be within the specified time. If so, the process proceeds to step S19.
In step S18, the optical axis adjustment (drift adjustment process) of the radar 1 is performed based on the value of the deviation angle θ averaged in step S16. Specifically, the position in the left-right direction (scanning direction) of the center position of the detection area is changed by the shift angle θ by the above-described soft optical axis adjustment. When the deviation angle θ is out of the soft optical axis adjustable range, the mounting angle of the optical head of the radar 1 may be mechanically changed. That is, a drive mechanism that drives the optical head of the radar 1 may be provided, and the optical axis may be mechanically adjusted by controlling the drive mechanism.
[0026]
On the other hand, in step S19, correction (drift adjustment processing) of the yaw rate sensor 21 is performed based on the value of the deviation angle θ averaged in step S16. Specifically, the value of the deviation angle θ is converted into a yaw rate value, and the value ΔYaw obtained thereby is updated and set as a correction value for the yaw rate sensor 21 to be used thereafter. For example, an average value of V / Y is obtained from a value for a specified number of distances Y to the stop and the vehicle speed V (corresponding to a value for the specified number of deviation angles θ described above), and this is further shifted. By multiplying the average value of the angle θ, a movement amount value ΔYaw (= θ · V / Y) converted into a yaw rate value is obtained. After that, the output of the yaw rate sensor 21 is set so that the value of ΔYaw is corrected as a correction value (the value of ΔYaw is added or subtracted). As a result, in a state immediately after the drift adjustment is executed with the optical axis of the radar 1 being accurate, the output (after correction) of the yaw rate sensor is extremely accurate without the influence of the drift component.
Note that after step S18 or S19, the process returns to step S11.
[0027]
According to the drift adjustment process described above, the output (after correction) of the yaw rate sensor is first performed at least immediately after the vehicle is stopped and this drift adjustment is performed by the drift adjustment during stoppage of FIG. ) Is extremely accurate without the influence of drift components. For this reason, if the above-mentioned prescribed time (see step S17) is set sufficiently short, the optical axis adjustment of the radar 1 executed in step S18 is extremely accurate without being affected by the drift over time of the yaw rate sensor. It becomes. As a result, even if the optical axis shift of the radar 1 occurs due to a shock or the like while the manga is running, another expensive sensor is connected when the condition for the process to proceed to step S18 in FIG. Without using it, this optical axis shift is corrected accurately and appropriately. In addition, according to experiments by the inventors, it has been found that the conventional optical axis deviation of about 1 m in front of 100 m can be significantly reduced to about 40 cm by such treatment.
Further, after the elapsed time after the start of traveling reaches the specified time, the drift adjustment of the yaw rate sensor 21 in step S19 is executed every time the specified number of new deviation angles θ is calculated, and the yaw rate sensor 21 Therefore, the information from the yaw rate sensor 21 is maintained in an accurately adjusted state in most cases even when the vehicle is stopped or running without using another expensive sensor. This is because the optical axis deviation of the radar 1 rarely occurs, and even if the function of step S18 is not provided, the adjustment operation of step S19 is accurate with high probability. In addition, in the case of this example, even if Mangaichi Step S19 is executed, the optical axis deviation of the radar 1 has occurred, and the adjustment in Step S19 becomes temporarily inaccurate due to the influence of this optical axis deviation. If the vehicle then stops and restarts, steps S2 and S18 described above are executed, and both the yaw rate sensor 21 and the radar 1 are newly adjusted accurately. That is, the state in which the information of either the yaw rate sensor 21 or the radar 1 is inaccurate has a configuration that does not always last. Rather, in most cases, both are always accurately adjusted.
[0028]
In addition, this invention is not restricted to the said example of an aspect, There can exist various aspects and deformation | transformation.
For example, when the radar 1 is accurately adjusted at the time of shipment and then firmly attached to the vehicle body so as not to cause an axial deviation, step S18 (or step S17) is deleted. Alternatively, the drift adjustment (steps S1 and S2) during stoppage may not be performed.
Further, in the above-described processing of FIG. 2B, when the prescribed number of θ data cannot be collected within the prescribed time, step S18 is not executed. For example, the processing contents may be such that the radar is always adjusted first after departure.
[0029]
Moreover, in the said embodiment, although the object for calculating | requiring the movement amount (shift angle | corner (theta) etc.) of this invention is limited to a stop thing, it is not restricted to this. When the object is not a stationary object, Vy and V are not equal, and the expression corresponding to the above-described expression (4) becomes slightly complicated, but adjustment can be performed by the same processing.
Further, there may be a configuration in which the adjustment at the time of traveling of the yaw rate sensor is performed independently of the processing of FIG. 2B (a configuration in which step S19 is deleted in FIG. 2B). For example, when it is determined from the observation result of the radar 1 that the host vehicle is in a straight traveling state, a processing routine for performing the same adjustment (zero point correction) on the yaw rate sensor as in step S2 may be separately executed. .
[0030]
Further, the forward object detection means of the present invention is not limited to a radar using laser light, but may be a radar using radio waves or sound waves, for example. Moreover, it is not limited to a radar, For example, what detects the position of a front object, etc. with a television camera etc. may be used.
Further, the lateral behavior detecting means of the present invention is not limited to a yaw rate sensor as long as it can obtain some lateral behavior information (including steering angle information) of the vehicle. In the embodiment, the axis adjustment of the radar (front object detection means) is automatically performed. However, instead of executing the process of adjusting the axis automatically in step S18 of FIG. It is also possible to simply notify the driver or the like of the occurrence of an axis misalignment by displaying an axis misalignment error display or the like if the above value is compared with an acceptable value. In this case, the driver or the like knows the occurrence of the shaft misalignment by this notification, and can make adjustments by himself or by bringing the vehicle to a repair shop for adjustment, thereby improving the state in which the radar information is inaccurate.
[0031]
【The invention's effect】
The vehicle detection device according to the present invention includes at least a lateral direction behavior detection unit based on information detected by each detection unit (a front object detection unit, a lateral direction behavior detection unit, and a vehicle speed detection unit) during travel of the vehicle. In-travel adjustment means for executing the drift adjustment processing of the vehicle.
In other words, at least the drift adjustment processing of the lateral behavior detecting means is executed during traveling of the vehicle based on information by the detecting means including the front object detecting means. According to the information during traveling of the vehicle by each detecting means including the forward object detecting means, a value corresponding to the drift component of the lateral behavior detecting means can be obtained accurately as in the above-described embodiment. For this reason, the drift adjustment of the lateral behavior detecting means can be accurately realized especially during traveling without using another expensive sensor, and in particular, the information of the lateral behavior detecting means can be more accurately maintained.
[0032]
Further, the lateral behavior detecting means is a yaw rate sensor for detecting the yaw rate of the vehicle, and the yaw rate sensor drift adjustment processing (for example, the processing in step S2 described above) is stopped while the vehicle is stopped. When the middle adjustment means is provided, the zero point of the yaw rate sensor can be accurately adjusted accurately every time the vehicle stops without being affected by the inaccuracy of the information of the front object detection means. By the way, if the configuration is such that the adjustment during the stop is not performed, when the information of the front object detection means becomes inaccurate (for example, when a radar axis deviation occurs), Adjustment of the direction behavior detection means (in this case, the yaw rate sensor) during travel may be inaccurate, and the information on the lateral behavior detection means may remain inaccurate for a long time. Such a problem can be avoided if the configuration is adjusted. As described above, the adjustment of the yaw rate sensor while the vehicle is stopped can be easily and accurately performed without using the information of other sensors (particularly the forward object detection means).
[0033]
Further, when the elapsed time from the time when the vehicle starts to travel from the stop state is within a specified time, the running adjustment means is a detection means (generally, a forward drift detector) that does not drift with time. When the drift adjustment processing of the object detection means, such as radar, is executed and the elapsed time exceeds a specified time, the detection means having a drift with time (generally, a lateral behavior detection means, For example, when the drift adjustment processing of the yaw rate sensor) is executed, there are the following advantages.
That is, before the information on the detecting means with drift over time becomes inaccurate due to the drift with time, the information on the detecting means without drift with time is more accurately based on the information on each detecting means including the detecting means with time drift. The information of the detection means having the drift over time is adjusted more effectively based on the information of each detection means including the detection means that is adjusted and then accurately adjusted without drift with time. For this reason, any detection means is always maintained in a more accurate state as a whole.
In particular, when the yaw rate sensor, which is a detecting means having a drift with time, is adjusted even while stopped as described above, the information of the yaw rate sensor immediately after the start of traveling is extremely accurate, so there is no drift with time. For example, the information of the radar as the detection means is adjusted to be extremely accurate at the beginning of traveling by adjusting within the specified time based on the accurate information of the yaw rate sensor. After that, the information of the yaw rate sensor, which may be inaccurate due to drift over time, is adjusted appropriately and appropriately based on the information of each detecting means including the radar that has been adjusted extremely accurately in this way, and is always in an extremely accurate state. As a result, the information of any sensor is always extremely accurate.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a vehicle detection device including a radar and a yaw rate sensor.
FIG. 2 is a flowchart illustrating drift adjustment processing of the vehicle detection device.
[Explanation of symbols]
1 Laser radar (front object detection device)
17 Control circuit (adjustment means during running, adjustment means during stop)
21 Yaw rate sensor (transverse behavior detection means)
31 Vehicle speed sensor (vehicle speed detection means)

Claims (6)

Front object detection means for detecting at least position information of an object in front of the vehicle, lateral behavior detection means for detecting lateral behavior information of the vehicle, and vehicle speed detection for detecting the traveling speed of the vehicle A vehicle detection device having means,
During running of the vehicle, on the basis of the information detected by the detecting means, e Bei traveling in adjusting means for performing a drift adjustment process of at least said lateral behavior detecting means,
The traveling adjustment means includes:
The distance to the object detected by the front object detection means, the lateral relative speed of the object, the relative speed in the front-rear direction of the object, the vehicle speed detected by the vehicle speed detection means, and the lateral behavior detection From the behavior information in the lateral direction of the vehicle detected by the means, a movement amount corresponding to the combined value of the drift component of each detection means is obtained, and the forward object detection means or the lateral direction behavior detection means is determined by the calculated movement amount value. The drift detection processing is realized by setting so as to correct the value of the information of the vehicle. Front object detection means for detecting at least position information of an object in front of the vehicle, lateral behavior detection means for detecting lateral behavior information of the vehicle, and vehicle speed detection for detecting the traveling speed of the vehicle A vehicle detection device having means,
  During traveling of the vehicle, based on information detected by each detection means, comprising at least a traveling adjustment means for executing a drift adjustment process of the lateral behavior detection means,
  The traveling adjustment means includes:
  Based on the information detected by the front object detection means and the vehicle speed detection means, when the presence of a stop object is recognized in front of the vehicle,
  The distance to the stop object detected by the front object detection means, the lateral relative speed of the stop object, the vehicle speed detected by the vehicle speed detection means, and the vehicle detected by the lateral behavior detection means The amount of movement corresponding to the combined value of the drift component of each detection means is obtained from the behavior information in the lateral direction, and the information value of the forward object detection means or the lateral direction behavior detection means is corrected by the obtained movement amount value. The drift detection processing is realized by setting so as to perform the vehicle detection device. Said lateral behavior detection means, vehicle detection device according to claim 1 or 2, characterized in that a yaw rate sensor for detecting the yaw rate of the vehicle as the behavior information. The vehicle detection device according to claim 3 , further comprising a stop adjustment unit that executes drift adjustment processing of the yaw rate sensor while the vehicle is stopped. The running adjustment means performs drift adjustment processing of the forward object detection means when the elapsed time from the time when the vehicle starts running from a stopped state is within the specified time, and the elapsed time is the specified time. If it is beyond the vehicle detection device according to claim 4, characterized in that executing the drift adjustment process of the yaw rate sensor. The running adjustment means, when the elapsed time from the time when the vehicle starts running from the stop state is within a specified time, performs the drift adjustment processing of the detection means without drift with time among the detection means, the time when the time exceeds the specified time, the vehicle detection device according to claim 1 or 2, characterized in that executing the drift adjustment process of a detecting means of a time drift of the detection means.

Images