JP5312493B2 - Automotive radar equipment - Google Patents

Description

  The present invention relates to an on-vehicle radar device that is mounted on a vehicle and detects the distance to a target by transmitting and receiving electromagnetic waves.

  An on-vehicle radar device mounted on a vehicle is used for monitoring the periphery of the host vehicle (for example, an automobile). The in-vehicle radar device radiates electromagnetic waves around the host vehicle, receives the electromagnetic waves reflected by the target, and based on the received electromagnetic waves, the distance between the host vehicle and the target, the relative speed of the host vehicle with respect to the target, or The position or direction of the target is detected.

  In addition, as an application that uses an on-vehicle radar device, an automatic speed control system that realizes auto-cruise control and a collision warning with a target are detected and a warning is given to the driver. In some cases, a pre-crash safety system in which control is performed to protect a person riding in a vehicle is already known.

  When detecting the position and direction of a target that exists in front of the host vehicle, the on-vehicle radar device used for these applications is generally based on the traveling direction of the host vehicle during straight traveling where the steering angle is zero. It is said. Therefore, it is necessary to make the vehicle central axis that is the traveling direction of the host vehicle coincide with the scanning central axis of the in-vehicle radar device.

  However, if there is a discrepancy (axis misalignment) between the vehicle center axis, which is the traveling direction of the host vehicle, and the scanning center axis of the in-vehicle radar device due to vehicle assembly errors or aging of the in-vehicle radar device, the in-vehicle There has been a problem that the radar apparatus may erroneously detect the position and direction of the target and cause the application of the on-vehicle radar apparatus to malfunction.

  Therefore, in order to solve the above problem, the straight traveling state of the host vehicle is determined based on the detection state of the preceding vehicle by the obstacle detection means that detects the obstacle (target) existing in front of the traveling host vehicle. Correction that performs detection angle correction based on the deviation of the detection direction by the obstacle detection unit with respect to the traveling direction of the host vehicle when the straight vehicle state determination unit and the straight vehicle state determination unit determine that the host vehicle is in a straight ahead state An obstacle detection device (vehicle-mounted radar device) including means has been proposed (see, for example, Patent Document 1).

  Further, the relative speed of the obstacle with respect to the host vehicle is calculated based on the distance and angle to the obstacle (target) detected by the vehicle obstacle detection device (vehicle radar device), and the obstacle is calculated from the relative speed. If the size and direction of the relative movement vectors of the object recognition means for determining whether the object is a moving object or a stop object and a plurality of different stationary objects calculated by the object recognition means are the same, The straight travel determination means that determines that the vehicle is traveling straight, and the angle that the relative movement vector forms with the irradiation center axis of the vehicle obstacle detection device when the host vehicle is traveling straight is calculated as the amount of deflection of the vehicle travel axis. The center axis deflection amount of the vehicle obstacle detection device comprising: a deflection amount calculation means for performing the correction; and an angle correction means for correcting the angle of the obstacle detected by the vehicle obstacle detection device based on the deflection amount Positive apparatus has been proposed (e.g., see Patent Document 2).

  In addition, the distance from the vehicle to the preceding vehicle so that the environment can be recognized accurately even when the vehicle or the preceding vehicle is not traveling in the center of the road and the traveling road is curved. The vehicle's lateral position detection detects the lateral position of the preceding vehicle on the road from the image obtained by the distance / direction detecting means (vehicle radar device) for detecting the direction and the camera installed on the host vehicle. A vehicle lateral position detecting means for detecting a lateral position on the road of the own vehicle from the camera image, a road curvature detecting means for detecting a road curvature from the camera image, a preceding vehicle and the own vehicle, A radar center axis automatic correction device has been proposed that includes a center axis direction estimation means for estimating the radar center axis direction from the positional relationship and road curvature, and a center axis correction means for correcting the direction of the center axis (for example, Patent Document 3).

  That is, in Patent Documents 1 and 2, the straight traveling state of the host vehicle is determined based on the detection state of the preceding vehicle, and the detection direction (irradiation center axis) of the obstacle detection means with respect to the traveling direction of the host vehicle (vehicle traveling axis) is determined. The detection angle is corrected using the deviation. That is, the axis deviation correction process between the vehicle center axis, which is the traveling direction of the host vehicle, and the scanning center axis of the in-vehicle radar device is executed when the host vehicle travels straight ahead.

  Further, in Patent Document 3, by detecting the lateral position on the road of a preceding vehicle from an image obtained by a camera installed on the own vehicle, the radar can be used even when the own vehicle is traveling on a curve. The center axis can be automatically corrected.

JP-A-6-290398 Japanese Patent No. 4038944 JP-A-9-218265

However, the prior art has the following problems.
In Patent Documents 1 to 3, the axis misalignment correction processing between the vehicle center axis, which is the traveling direction of the host vehicle, and the scanning center axis of the in-vehicle radar device is performed between the host vehicle and the target during normal travel of the host vehicle. This is executed in addition to the normal detection process of detecting the distance, the relative speed of the host vehicle with respect to the target, or the position or direction of the target. For this reason, there is a problem that the amount of calculation of the in-vehicle radar device increases and the processing load and processing time increase.

  In addition, when executing the axis misalignment correction processing between the vehicle center axis and the scan center axis, the target always exists within a range in which the on-vehicle radar device can detect an object with high accuracy, and the axis misalignment correction is performed. There is also a problem that it is not always possible to secure a sufficient time for processing.

  The present invention has been made to solve the above-described problems, and reduces the influence on the normal detection process due to the calculation required for the axis misalignment correction process between the vehicle center axis and the scan center axis. It is an object of the present invention to obtain an in-vehicle radar device that can execute a displacement correction process with high accuracy.

  The on-vehicle radar device according to the present invention is mounted on a vehicle, radiates electromagnetic waves to the periphery of the vehicle, and is reflected by the target, based on the received electromagnetic waves, the distance between the vehicle and the target, and the relative speed of the vehicle with respect to the target. A vehicle-mounted radar device that detects at least one of the position and direction of the target as target information, a vehicle reverse detection unit that detects a reverse drive state of the vehicle, and a reverse distance detection unit that detects a reverse drive distance of the vehicle When the vehicle is in the reverse drive state, based on the vehicle turn information and the reverse travel distance, the turning angle acquisition unit that acquires the actual turning angle of the vehicle, and when the vehicle is in the reverse drive state, based on the target information, Based on the difference between the actual turning angle and the estimated turning angle when the vehicle is in the reverse drive state and the turning angle estimating unit that calculates the estimated turning angle of the vehicle, And axis deviation correction processing unit for correcting the axial misalignment of the scanning center axis of the in-vehicle radar device with the mandrel, but with the.

According to the on-vehicle radar device according to the present invention, the axis deviation correction processing unit is calculated by the actual turning angle of the vehicle acquired by the turning angle acquisition unit and the turning angle estimation unit when the vehicle is in the reverse drive state. Based on the difference from the estimated turning angle of the vehicle, the axis deviation between the vehicle center axis of the vehicle and the scanning center axis of the in-vehicle radar device is corrected.
As a result, the shaft misalignment correction processing that is conventionally performed when the vehicle is traveling straight ahead can be performed when the vehicle is moving backward or turning, for example, when the vehicle is parked in a parking lot. Therefore, the normal detection process and the axis deviation correction process can be distinguished from each other, and the influence on the normal detection process due to the calculation required for the axis deviation correction process between the vehicle center axis and the scanning center axis can be reduced.
In addition, since the misalignment correction process is executed when the vehicle is moving backward or turning, it is possible to secure the target within a range in which the in-vehicle radar device can detect an object with relatively high accuracy. Further, since the backward and turning operations of the vehicle are generally performed at a low speed, it is possible to secure a sufficient time for the axis misalignment correction processing. Therefore, it is possible to easily ensure a traveling environment suitable for the shaft misalignment correction process, and it is possible to execute the shaft misalignment correction process with high accuracy.

It is a block block diagram which shows the vehicle-mounted radar apparatus which concerns on Embodiment 1 of this invention. It is explanatory drawing which shows a mode that the vehicle by which the vehicle-mounted radar apparatus which concerns on Embodiment 1 of this invention is mounted is reversely parked in a parking lot. It is explanatory drawing which shows the transition state of the target position by the output of the vehicle-mounted radar apparatus which concerns on Embodiment 1 of this invention. It is explanatory drawing which shows the relationship between a target detection distance and a detection distance error in the vehicle-mounted radar apparatus which concerns on Embodiment 1 of this invention. It is explanatory drawing which shows the antenna pattern of the vehicle-mounted radar apparatus which concerns on Embodiment 2 of this invention. It is explanatory drawing which expands and shows angle 0 degree vicinity of the antenna pattern shown in FIG.

  Hereinafter, preferred embodiments of an on-vehicle radar device according to the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts will be described with the same reference numerals.

Embodiment 1 FIG.
FIG. 1 is a block configuration diagram showing an in-vehicle radar device 1 according to Embodiment 1 of the present invention. In FIG. 1, an on-vehicle radar device 1 is mounted on a host vehicle, radiates electromagnetic waves to the periphery of the host vehicle, and reflects the distance between the host vehicle and the target based on the received electromagnetic waves. At least one of the relative speed of the host vehicle and the position and direction of the target is detected as target information.

  The in-vehicle radar device 1 includes a vehicle reverse detection unit 11, a reverse distance detection unit 12, a turning angle acquisition unit 13, a turning angle estimation unit 14, a recording unit 15, and an axis deviation correction processing unit 16. Here, the vehicle reverse detection unit 11, the reverse distance detection unit 12, the turning angle acquisition unit 13, the turning angle estimation unit 14, the recording unit 15, and the axis deviation correction processing unit 16 store a CPU (Central Processing Unit) and a program. It comprises a microprocessor (not shown) having a memory.

  The vehicle reverse detection unit 11 detects the reverse state of the host vehicle. Specifically, when the vehicle reverse detection unit 11 detects that the shift lever position of the host vehicle has been switched to the rear via the in-vehicle network or the like, for example, as shift lever position information from the shift lever ECU. Next, the reverse state of the host vehicle is determined. The vehicle reverse detection unit 11 determines the reverse state of the host vehicle when detecting reverse rotation of a wheel speed sensor provided in the host vehicle or based on target information detected by the in-vehicle radar device 1. May be.

  The reverse distance detection unit 12 detects the reverse distance of the host vehicle. Specifically, the reverse distance detection unit 12 is based on, for example, an output of an odometer, an integrated value of the vehicle speed and the observation time, or a time integral value of the rotational speed of the wheel of the host vehicle obtained by a wheel speed sensor. Calculate the reverse distance of the host vehicle.

  When the host vehicle is in a reverse drive state, the turn angle acquisition unit 13 performs actual turn of the host vehicle during a certain observation period based on the turn information of the host vehicle and the reverse drive distance detected by the reverse drive distance detection unit 12. Get the angle. Here, the turning information of the host vehicle indicates, for example, output from a handle angle sensor, a yaw rate sensor, a G sensor, a GPS, a toe angle sensor, or the like provided in the host vehicle.

Specifically, the turning angle acquisition unit 13 starts acquisition when the vehicle reverse detection unit 11 detects a reverse state of the host vehicle, and at times t ₀ , t ₁ ,..., T _n from the acquisition start. The turning angles θ _V (t ₀ ), θ _V (t ₁ ),..., Θ _V (t _n ) of the host vehicle are acquired and recorded in the recording unit 15. Further, the turning angle acquisition unit 13 accumulates these turning angles from time t ₀ to t _n , calculates the total turning angle (actual turning angle) θ _VTotal and records it in the recording unit 15. The total turning angle θ _VTotal is expressed by the following equation.

θ _VTotal = θ _V (t ₀ ) + θ _V (t ₁ ) +... + θ _V (t _n )

  The turning angle estimation unit 14 calculates the estimated turning angle of the host vehicle based on the target information detected by the in-vehicle radar device 1 when the host vehicle is in the reverse drive state. Specifically, the turning angle estimation unit 14 captures, as a stationary object, a target whose detection result is relatively moved according to the turning state of the vehicle among at least one target detected by the in-vehicle radar device 1.

Further, the turning angle estimation unit 14 records the position information of the stopped object in the recording unit 15 from the time t ₀ to the time t _{n in the same} manner as the turning angle acquisition unit 13, and the detected position information of the stopped object (target). From this, the total transition angle (estimated turning angle) θ _Total obtained by obtaining and integrating each of the transition angles θ _{t (n−n−1)} is calculated and recorded in the recording unit 15. Here, the reason for using the target whose detection result relatively moves according to the turning state of the host vehicle is to use the stopped target.

  Hereinafter, the operation of the turning angle estimation unit 14 will be described in detail with reference to FIGS. FIG. 2 is an explanatory diagram showing a state in which the host vehicle 2 on which the in-vehicle radar device 1 according to the first embodiment of the present invention is mounted is moved backward in the parking lot and parked. FIG. 3 is an explanatory diagram showing a transition state of the target position by the output of the in-vehicle radar device 1 according to the first embodiment of the present invention.

In FIG. 2, the target 4 detected by the on-vehicle radar device 1 after the host vehicle 2 starts parking in the parking space 3 on the output of the on-vehicle radar device 1 is shown in FIG. _{t 0, t 1, t 2} , ···, at _{t n,} transitions distance y _{(t n)} and the horizontal direction x _{(t n).}

At this time, the turning angle estimation unit 14, the time _{t 0, t 1, t 2} , ···, from the distance y _{(t n)} and the horizontal direction x _{(t n)} at _{t n,} each transition angle theta _{t (1 −0)} , θ _{t (2-1)} ,..., Θ _{t (n−n−1)} are calculated as follows.

Further, the turning angle estimation unit 14 integrates these transition angles, calculates the total transition angle θ _Total , and records it in the recording unit 15. The total transition angle θ _Total is expressed by the following equation.

θ _Total = θ _{t (1-0)} + θ _{t (2-1)} +... + θ _{t (n−n−1)}

In FIG. 3, the number of targets is one for the sake of simplicity. Originally, however, there are a plurality of targets around the host vehicle in the parking lot. Therefore, since the targets are sequentially switched in the front direction of the host vehicle, the on-vehicle radar device 1 sequentially switches the first target to be set between the times t ₀ and t _n and changes the transition angle θ _{t (n -N-1)} may be integrated.

The recording unit 15 includes the turning angle θ _V (t ₀ ), θ _V (t ₁ ),..., Θ _V (t _n ) of the host vehicle acquired by the turning angle acquisition unit 13 and the calculated total turning angle. θ _VTotal , the transition angles θ _{t (1-0)} , θ _{t (2-1)} ,..., θ _{t (n−n−1)} calculated by the turning angle estimation unit 14 and the calculated total transition Data necessary for the axis misalignment correction process such as the angle θ _Total is stored.

The axis deviation correction processing unit 16 determines the traveling direction of the _host vehicle based on the difference between the actual turning angle (total turning angle θ _VTotal ) and the estimated turning angle (total transition angle θ _Total ) when the vehicle is in the reverse _drive state. The axis deviation between the vehicle central axis and the scanning central axis of the in-vehicle radar device 1 is corrected.

Specifically, the axis deviation correction processing unit 16 starts the turning angle acquisition unit 13 and the turning angle estimation unit 14 when the backward traveling state of the host vehicle is detected by the vehicle backward detection unit 11, and the total turning angle θ _When either _VTotal or the total transition angle θ _Total becomes a predetermined angle or more, the operations of the turning angle acquisition unit 13 and the turning angle estimation unit 14 are terminated.

Subsequently, the axis deviation correction processing unit 16 _{compares the} acquired total turning angle θ _VTotal and the total transition angle θ _Total and, based on the difference, _sets the axis deviation angle of the in-vehicle radar device 1 as an in-vehicle radar. The target detection position of the apparatus 1 is offset and corrected.

  The scene in which the effect of the present invention is exhibited assumes that the host vehicle is parked in a parking lot, and the advantage thereof is that the vehicle-mounted radar device 1 can detect an object with relatively high accuracy. Since the target can be secured, the backward movement of the vehicle is generally performed at a low speed, the time required for the axis deviation correction process can be ensured, and the detection process and axis deviation inherent in the in-vehicle radar device 1 can be ensured. This is because the correction process can be distinguished.

  Here, the detection distance error with respect to the target detection distance of the in-vehicle radar device 1 is small at a short distance and large at a long distance, as shown in FIG. That is, the detection distance error depends on the target detection distance. Therefore, the axial deviation correction accuracy varies depending on the distance to the target. Accordingly, when the host vehicle is parked, a target within a relatively high detection accuracy range can be used for the axis misalignment correction process, so that the target detection distance error is small, and as a result, the axis misalignment is performed under good conditions. Correction processing can be executed.

  At this time, since the on-vehicle radar device 1 does not require a long target detection distance, the power consumption of the on-vehicle radar device 1 is reduced by reducing the power of the transmission radio wave of the on-vehicle radar device 1 during this time. can do.

As described above, according to the first embodiment, the axis deviation correction processing unit is calculated by the actual turning angle of the vehicle acquired by the turning angle acquisition unit and the turning angle estimation unit when the vehicle is in the reverse drive state. Based on the difference between the estimated turning angle of the vehicle and the vehicle center axis of the vehicle and the scanning center axis of the in-vehicle radar device, the axis deviation is corrected.
As a result, the shaft misalignment correction processing that is conventionally performed when the vehicle is traveling straight ahead can be performed when the vehicle is moving backward or turning, for example, when the vehicle is parked in a parking lot. Therefore, the normal detection process and the axis deviation correction process can be distinguished from each other, and the influence on the normal detection process due to the calculation required for the axis deviation correction process between the vehicle center axis and the scanning center axis can be reduced.
In addition, since the misalignment correction process is executed when the vehicle is moving backward or turning, it is possible to secure the target within a range in which the in-vehicle radar device can detect an object with relatively high accuracy. Further, since the backward and turning operations of the vehicle are generally performed at a low speed, it is possible to secure a sufficient time for the axis misalignment correction processing. Therefore, it is possible to easily ensure a traveling environment suitable for the shaft misalignment correction process, and it is possible to execute the shaft misalignment correction process with high accuracy.

In the first embodiment, when either the total turning angle θ _VTotal or the total transition angle θ _Total becomes an arbitrary angle, the axis deviation correction processing unit 16 performs the turning angle acquisition unit 13 and the turning angle estimation unit 14. Explained that the operation of was finished. However, the present invention is not limited to this, and the shaft misalignment correction processing unit 16 acquires the position information of the shift lever from the shift lever ECU via the in-vehicle network or the like, and the shift lever of the own vehicle is set to either parking or neutral. The operation of the turning angle acquisition unit 13 and the turning angle estimation unit 14 may be terminated by detecting that the switch has been made, the side brake or the foot brake has been applied, or the clutch has been depressed.

  Moreover, although the said Embodiment 1 demonstrated that the own vehicle was in the reverse drive state, even if the own vehicle parked from the front in the parking space 3 (refer FIG. 2), the own vehicle was advanced. Since the vehicle often goes backward once in order to adjust the vehicle direction later, the same effect as in the first embodiment can be expected.

Embodiment 2. FIG.
FIG. 5 is an explanatory diagram showing an antenna pattern of the in-vehicle radar device 1 according to Embodiment 2 of the present invention. FIG. 6 is an explanatory diagram showing an enlargement of the vicinity of an angle of 0 degrees of the antenna pattern shown in FIG.

In the first embodiment, the turning angle acquisition unit 13 is based on turning information of the own vehicle that is output from a handle angle sensor, a yaw rate sensor, a G sensor, a GPS, a toe angle sensor, and the like provided in the own vehicle. It has been described that the total turning angle θ _VTotal is calculated. However, the present invention is not limited to this. Instead of the turning information of the own vehicle, the antenna pattern corresponding to the scanning angle of the in-vehicle radar device 1 is recorded as known information in the recording unit 15, and the turning angle acquisition unit 13 performs the time t. _{Based on} the transition angle θ _{t (n−n−1) of} at least one target detected by the in-vehicle radar device 1 and the change amount ΔG of the relative gain of the reflected wave between ₀ and t _n. The total turning angle θ _VTotal may be calculated.

As shown in FIG. 6, the antenna pattern of the on-vehicle radar device 1 has a maximum relative gain G _{0 in the} radar front direction (angle 0 degree) due to the antenna directivity, and has an angle ± θ _x characteristic. The turning angle of the host vehicle can be detected with respect to the target based on the relative gain change amount ΔG.

Thereby, since the total turning angle θ _VTotal in the first embodiment can be calculated, the same effect as in the first embodiment can be obtained. In addition, it is not influenced by the accuracy difference of other vehicle sensors such as a handle angle sensor, a yaw rate sensor, a G sensor, a GPS, a toe angle sensor, and the like, and is completed only by the performance of the in-vehicle radar device 1 and executes an axis deviation correction process. can do.

Embodiment 3 FIG.
In-vehicle radar device 1 according to Embodiment 3 of the present invention further includes radar scanning range changing means for changing the scanning range of the radar in addition to in-vehicle radar device 1 of Embodiments 1 and 2.

  Specifically, the radar scanning range changing means is, for example, an array antenna composed of a plurality of element antennas for transmitting or receiving electromagnetic waves, and the antenna pattern can be expanded in signal processing by digital beam forming (DBF). Adjustments such as narrowing can be made.

  Here, the radar scanning range changing means widens or narrows the antenna pattern by the DBF while the axis deviation correction processing unit 16 is executing the axis deviation correction processing, so that the radar of the in-vehicle radar device 1 can be changed. Change the scanning range. At this time, the on-vehicle radar device 1 lowers the threshold value for determining the degree of danger such as a collision of the host vehicle while the shaft misalignment correction processing unit 16 is performing the shaft misalignment correction processing, so that the alarm level for the driver is reduced. May be raised.

  The detection performance of the in-vehicle radar device 1 is determined depending on the reflected wave level (S / N ratio) from the target. On the other hand, as is clear from FIG. 5, the gain of the antenna pattern of the in-vehicle radar device 1 decreases as the angle (absolute value) from the scanning center of the in-vehicle radar device 1 increases.

  Therefore, even if the target is at the same distance from the host vehicle, the target located on the side from the front of the host vehicle has a lower S / N ratio. Difficult to do.

  Therefore, in order to solve this problem, while the shaft misalignment correction processing unit 16 is executing the shaft misalignment correction processing, the threshold for determining the danger level of the in-vehicle radar device 1 such as a collision of the host vehicle is lowered, and the driving is performed. By raising the alarm level to the person, the detection performance of the target existing beside the front of the host vehicle can be improved.

This is particularly effective when it is necessary to warn the driver of the danger of collision with the target from the side rather than the front of the host vehicle, such as a parking lot.
Accordingly, even when a target having a high possibility of contact or collision exists around the vehicle such as when the host vehicle is parked, a warning to the driver can be urged according to the traveling environment.

Embodiment 4 FIG.
In the first and second embodiments, when the vehicle reverse detection unit 11 detects the reverse state of the _host vehicle, the axis deviation correction processing unit 16 determines the difference between the total turning angle θ _VTotal and the total transition angle θ _Total. Based on this, it has been described that the axis misalignment correction process is executed.

  However, when the vehicle reverse detection unit 11 detects the reverse state of the host vehicle, secondary function processing such as fail determination, calibration, or dirt detection may be performed based on the detection result. .

  Specifically, the fail determination determines that the detection performance of the in-vehicle radar device 1 has deteriorated due to aged deterioration of the in-vehicle radar device 1 or the like. In addition, the calibration corrects that the target detection performance of the in-vehicle radar device 1 is deteriorated due to aging deterioration and temperature characteristics of the in-vehicle radar device 1, and keeps the radar property in a good state. In addition, the contamination detection notifies a decrease in detection performance due to contamination attached to the front direction of the in-vehicle radar device 1, for example, a radome or a part storing the radar.

  As a result, it is possible to distinguish between the normal detection process executed by the in-vehicle radar device 1 and the secondary function process, and therefore when the in-vehicle radar device 1 is executing the normal detection process. An increase in processing load and processing time due to the execution of the secondary function can be suppressed.

  DESCRIPTION OF SYMBOLS 1 Car-mounted radar apparatus, 2 Own vehicle, 3 Parking space, 4 Target, 11 Vehicle reverse detection part, 12 Reverse distance detection part, 13 Turning angle acquisition part, 14 Turning angle estimation part, 15 Recording part, 16 Axis shift correction process Department.

Claims (14)

A distance between the vehicle and the target, a relative speed of the vehicle with respect to the target, a relative speed of the vehicle, and an electromagnetic wave of the target mounted on the vehicle, radiating electromagnetic waves around the vehicle, reflected by the target, and received. An on-vehicle radar device that detects at least one of a position and a direction as target information,
A vehicle reverse detection unit for detecting a reverse state of the vehicle;
A reverse distance detection unit for detecting a reverse distance of the vehicle;
A turning angle acquisition unit for acquiring an actual turning angle of the vehicle based on the turning information of the vehicle and the reverse distance when the vehicle is in the reverse drive state;
A turning angle estimating unit that calculates an estimated turning angle of the vehicle based on the target information when the vehicle is in the reverse drive state;
When the vehicle is in the reverse drive state, an axial deviation between the vehicle center axis of the vehicle and the scan center axis of the in-vehicle radar device is corrected based on the difference between the actual turning angle and the estimated turning angle. An axis misalignment correction processing unit;
An on-vehicle radar device comprising: The swivel angle acquisition unit, time _{t 0,} t 1, · · ·, turning angle of the vehicle at _{t n θ V (t 0)} , θ V (t 1), ···, θ V (t n) _And calculating the actual turning angle θ _VTotal by accumulating the turning angle from time t ₀ to time t _n ,
The turning angle estimation unit captures a target whose detection result is relatively moved according to the turning state of the host vehicle as at least one target detected by the in-vehicle radar device, and detects the position information of the stopping object. 2. The in-vehicle radar according to claim 1, wherein the estimated turning angle θ _{Total obtained} by calculating and integrating the transition angles θ _{t (n−n−1)} from time t ₀ to time t _n is calculated. apparatus. Further comprising recording means for previously recording an antenna pattern with respect to the scanning angle of the in-vehicle radar device,
The turning angle acquisition unit is based on a change amount of a reflected wave level coming from at least one target detected by the antenna pattern and the in- vehicle radar device, instead of the turning information of the vehicle and the reverse travel distance. The on-vehicle radar device according to claim 1, wherein the actual turning angle is calculated. A radar scanning range changing means for changing a scanning range of the radar of the on-vehicle radar device;
The radar scanning range changing means changes the scanning range while the axis deviation correction processing unit is executing axis deviation correction processing. The on-vehicle radar device described in 1.   In the on-vehicle radar device, while the shaft misalignment correction processing unit is executing the shaft misalignment correction processing, the threshold for determining the risk of vehicle collision is lowered to raise the warning level for the driver. The on-vehicle radar device according to any one of claims 1 to 4.   The vehicle reverse detection unit detects a reverse drive state of the vehicle when detecting that the position of the shift lever of the vehicle is switched to the rear. The on-vehicle radar device according to claim 1.   6. The vehicle reverse detection unit according to claim 1, wherein the vehicle reverse detection unit detects a reverse drive state of the vehicle when detecting reverse rotation of a wheel speed sensor provided in the vehicle. The on-vehicle radar device described in 1.   The in-vehicle radar device according to any one of claims 1 to 5, wherein the vehicle reverse detection unit detects a reverse drive state of the vehicle based on the target information.   9. The vehicle-mounted radar device according to claim 1, wherein when the vehicle is in the reverse travel state, the power of a transmission radio wave is reduced as compared with a normal time. In-vehicle radar device.   The shaft misalignment correction processing unit terminates the operations of the turning angle acquisition unit and the turning angle estimation unit when the actual turning angle or the estimated turning angle becomes a predetermined angle or more. The in-vehicle radar device according to any one of claims 1 to 9, wherein the on-vehicle radar device is characterized.   The shaft misalignment correction processing unit detects that the shift lever of the vehicle has been switched to either parking or neutral, that the side brake or foot brake has been applied, or that the clutch has been depressed. The on-vehicle radar device according to any one of claims 1 to 9, wherein the operations of the turning angle acquisition unit and the turning angle estimation unit are terminated.   12. The on-vehicle radar device performs a fail determination for determining that the detection performance of the on-vehicle radar device has deteriorated when the vehicle is in the reverse drive state. The on-vehicle radar device according to any one of the above.   The on-vehicle radar device corrects a decrease in target detection performance of the on-vehicle radar device when the vehicle is in the reverse drive state, and executes calibration for maintaining the radar characteristics in a good state. The on-vehicle radar device according to any one of claims 1 to 12, wherein the on-vehicle radar device is characterized in that:   2. The on-vehicle radar device performs stain detection for notifying deterioration of detection performance due to stain attached to a front direction of the on-vehicle radar device when the vehicle is in the reverse drive state. The on-vehicle radar device according to any one of claims 1 to 13.

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