Angular error estimation device and angular error estimation method

Abstract

The present invention executes: first angular error estimation processing (S40) for determining an estimated first angular error value obtained by estimating an angular error in a radar device using azimuthal dependence of relative velocity with respect to a stationary object; second angular error estimation processing (S50) for calculating a stationary object movement direction in which the stationary object moves when viewed from a moving body if the moving body is assumed to be travelling straight, calculating the next distance to the stationary object at the next azimuth on the basis of the movement direction average value and the distance to the stationary object, calculating a true estimated angle value on the basis of the next distance and a reference movement direction in which the stationary object moves when there is no angular error, and determining an estimated second angular error value on the basis of the difference between the true estimated angle value and the next azimuth; and angular error integration processing (S60) for using the estimated first angular error value and / or the estimated second angular error value to estimate an angular error in an object detected by the radar device.

Description

Angle error estimation device and angle error estimation method CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is based on Patent Application No. 2024-129139 filed in Japan on August 5, 2024, and the contents of the original application are incorporated by reference in their entirety.

[0002] The present invention relates to an angle error estimation device and an angle error estimation method for estimating an angle error of a radar device.

[0003] Patent Document 1 discloses a technique for estimating an angle error of a radar device. The technique disclosed in Patent Document 1 estimates the angle error by utilizing the fact that the observed relative velocity of a stationary object is angle-dependent.

[0004] Patent Document 2 also discloses a technique for estimating the angle error of a radar device. In the technique disclosed in Patent Document 2, for each observation azimuth angle at which the radar device observes a stationary object, a stationary object inclination is calculated, which indicates the direction of movement of the stationary object as seen from the host vehicle, assuming that the host vehicle is traveling straight. Then, an average value of the stationary object inclination is calculated for each observation azimuth angle. Furthermore, a movement trajectory of the stationary object is calculated based on the average value of the stationary object inclination calculated for each observation azimuth angle. An angle error is calculated for each observation azimuth angle based on this movement trajectory of the stationary object and a reference movement trajectory set as the movement trajectory of the stationary object in the absence of an angle error. The contents of the prior art documents are incorporated by reference as explanations of the technical elements in this specification.

[0005] Japanese Patent No. 6358076 Japanese Patent Application Laid-Open No. 2024-56405

[0006] The technology disclosed in Patent Document 2 can accurately estimate the angle error even at the rear of the vehicle. However, the technology disclosed in Patent Document 2 assumes that the angle error is zero up to the start angle of the valid continuous section. Then, the observation azimuth angle θ calculated under this assumption ｎ＋１ The true angle estimate θ ｔｒｕｅ and the observation azimuth angle θ ｎ＋１ The difference between the observation azimuth angle θ ｎ＋１Therefore, if the angle error at the start angle of the valid continuous section is not zero, the accuracy of estimating the angle error decreases.

[0007] The present disclosure has been made in light of the above circumstances, and an object of the present disclosure is to provide an angle error estimation device and an angle error estimation method that can estimate the angle error of a radar device with higher accuracy.

[0008] The above object is achieved by the combination of features recited in the independent claims, and the subclaims define further advantageous specific examples. The reference numerals in parentheses in the claims correspond to specific aspects described in the following embodiments as one aspect, and do not limit the technical scope of the disclosure.

[0009] One disclosure of an angle error estimation device for achieving the above object is an angle error estimation device that is mounted on a moving body and estimates an angle error, which is an error in an observation azimuth angle observed by at least one radar device whose detection area includes a side of the moving body, and includes: an object detection information acquisition unit that acquires object detection information from the radar device, including a distance to an object present in the detection area, the observation azimuth angle of the object, and the relative speed of the object; a stationary object determination unit that determines whether an object is a stationary object based on the observation azimuth angle of the object, the relative speed, and the speed of the moving body; a first angle error estimation unit that determines a first angle error estimate value that estimates the angle error for each observation azimuth angle of the radar device by utilizing the azimuth angle dependency of the relative speed with respect to the stationary object; and a movement direction calculation unit that calculates, for each observation azimuth angle at which the stationary object is observed by the radar device, the direction in which the stationary object would move as seen from the moving body if the moving body were assumed to be moving straight, based on the object detection information of the stationary object determined by the stationary object determination unit and moving body trajectory information that specifies the movement trajectory of the moving body; an average calculation unit that calculates an average moving direction value by averaging, for each observation azimuth angle, moving directions of a plurality of stationary objects classified by observation azimuth angle; a distance calculation unit that calculates a next distance, which is the distance to the stationary object at a next azimuth angle obtained by adding a unit azimuth angle to the observation azimuth angle, based on the average moving direction value at the observation azimuth angle and the distance to the stationary object at the observation azimuth angle; a second angle error estimating unit that calculates a true angle estimate that estimates the azimuth angle of the stationary object detected by the radar device when there is no angle error, based on the next distance and a reference moving direction that is the moving direction of the stationary object when there is no angle error, and determines a second angle error estimate that estimates the angle error for each observation azimuth angle of the radar device based on the difference between the true angle estimate and the next azimuth angle; and an angle error integrated estimating unit that estimates the angle error of an object detected by the radar device using one or both of the first angle error estimate and the second angle error estimate.

[0010] This angular error estimation device includes two angular error estimation units, a first angular error estimation unit and a second angular error estimation unit, and estimates the angular error of an object detected by the radar device using one or both of the first angular error estimate and the second angular error estimate.

[0011] Because the first angle error estimator and the second angle error estimator use different angle error estimation methods, the first angle error estimate value estimated by the first angle error estimator and the second angle error estimate value estimated by the second angle error estimator are not necessarily the same, even for angle errors for the same observation azimuth angle. Because this angle error estimation device estimates both the first and second angle error estimate values, it can use one angle error estimate under conditions where the accuracy of the other angle error estimate decreases, or it can use the other angle error estimates in combination. This allows the angle error of the radar device to be estimated more accurately.

[0012] One disclosure of an angle error estimation method for achieving the above object is an angle error estimation method that is mounted on a moving body and estimates an angle error, which is an error in an observation azimuth angle observed by at least one radar device that is mounted on a moving body and includes a side of the moving body in its detection area, the method comprising: acquiring object detection information from the radar device, the object detection information including the distance to an object present in the detection area, the object's observation azimuth angle, and the object's relative speed; determining whether the object is a stationary object based on the object's observation azimuth angle, the relative speed, and the moving body's speed; determining a first angle error estimate that estimates the angle error for each observation azimuth angle of the radar device by utilizing the azimuth angle dependency of the relative speed with respect to the stationary object; calculating a stationary object movement direction, which is the direction in which the stationary object moves as seen from the moving body when it is assumed that the moving body is moving straight, for each observation azimuth angle at which the stationary object is observed by the radar device, based on the stationary object detection information and moving body trajectory information that specifies the movement trajectory of the moving body; calculating an average movement direction value by averaging a plurality of stationary object movement directions classified by observation azimuth angle, for each observation azimuth angle classification; This angle error estimation method calculates a next distance, which is the distance to the stationary object at a next azimuth angle obtained by adding a unit azimuth angle to the observation azimuth angle, based on an average value of the moving direction at the observation azimuth angle and the distance to the stationary object at the observation azimuth angle; calculates a true angle estimate, which estimates the azimuth angle of the stationary object that the radar device would detect if there were no angle error, based on the next distance and a reference moving direction, which is the moving direction of the stationary object if there were no angle error; determines a second angle error estimate, which estimates the angle error for each observation azimuth angle of the radar device, based on the difference between the true angle estimate and the next azimuth angle; and estimates the angle error of the object detected by the radar device using one or both of the first angle error estimate and the second angle error estimate.

[0013] 7 is a block diagram showing the configuration of an information providing device for a vehicle. FIG. 1 is a diagram showing the installation position of a radar device and an object detection area. FIG. 2 is a diagram showing the process of correcting the observation azimuth angle by a control unit. FIG. 3 is a diagram explaining a method of determining whether an object is stationary. FIG. 4 is a diagram showing the first angle error estimation process of FIG. 3. FIG. 5 is a diagram explaining a first angle error estimated value. FIG. 6 is a diagram showing the second angle error estimation process of FIG. 3. FIG. 7 is a diagram explaining the stationary object inclination calculation process of FIG. 7. FIG. 8 is a diagram explaining a method of calculating the stationary object inclination. FIG. 9 is a diagram explaining a position change that occurs in the movement trajectory of a stationary object due to the turning of the host vehicle. FIG. 10 is a diagram showing the angle error estimation process of FIG. 7. FIG. 11 is a diagram explaining a method of calculating a radial distance. FIG. 12 is a diagram showing the angle error integration process of FIG. 3. FIG. 13 is a diagram explaining angle correction in mode 2.

[0014] [Embodiment] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. An information providing device 1 for a vehicle according to the present embodiment is mounted on a vehicle, which is an example of a moving body. The vehicle is, for example, a four-wheeled vehicle that travels on a road.

[0015] 1, the vehicular information providing device 1 includes a head-up display device 2, a left rear radar device 3, a right rear radar device 4, a vehicle speed sensor 5, a yaw rate sensor 6, and a control unit 7. Hereinafter, the vehicle equipped with the vehicular information providing device 1 will be referred to as the host vehicle VH.

[0016] The head-up display device 2 emits display light for displaying an image from below the windshield toward the windshield, allowing the driver to visually recognize the projected virtual image superimposed on the actual scenery ahead of the vehicle.

[0017] The left rear radar device 3 and the right rear radar device 4 transmit radar waves toward the periphery of the host vehicle VH and receive reflected radar waves. Hereinafter, the left rear radar device 3 and the right rear radar device 4 will also be referred to as the radar device 3 and the radar device 4, respectively. The left rear radar device 3 and the right rear radar device 4 are installed at the left end and the right end of the rear of the host vehicle VH, respectively.

[0018] The radar devices 3 and 4 employ, for example, the FMCW system, alternately transmitting radar waves in an uplink modulation section and radar waves in a downlink modulation section at a preset modulation period T, and receiving the reflected radar waves. As a result, the radar devices 3 and 4 detect, for each modulation period T, the distance to the point where the radar waves are reflected (hereinafter, observation point P) (hereinafter, observation distance R), the relative velocity with respect to observation point P (hereinafter, observation relative velocity Vr), and the azimuth angle at which observation point P is located (hereinafter, observation azimuth angle θ). The radar devices 3 and 4 also output observation point information indicating the detected observation distance R, observation relative velocity Vr, and observation azimuth angle θ of observation point P to the control unit 7.

[0019] The vehicle speed sensor 5 detects the speed v of the host vehicle VH and outputs a vehicle speed detection signal indicating the detection result. The yaw rate sensor 6 detects the yaw rate ω of the host vehicle VH and outputs a yaw rate detection signal indicating the detection result. The speed v and yaw rate ω of the host vehicle VH can identify the movement trajectory of the host vehicle VH. The speed v and yaw rate ω of the host vehicle VH are moving body trajectory information that identifies the movement trajectory of the host vehicle VH, which is a moving body.

[0020] The control unit 7 has a hardware configuration including at least one of a processor and a circuit. For example, the control unit 7 can be realized by a computer including a processor and a memory. Alternatively, the control unit 7 may not include a processor and may include a hardware circuit other than the processor, or may include a processor and a hardware circuit other than the processor.

[0021] In the example of FIG. 1 , the control unit 7 is an electronic control device mainly configured with a microcomputer including a CPU 11, a ROM 12, a RAM 13, etc. Various functions of the microcomputer are realized by the CPU 11 executing a program stored in a non-transitory tangible recording medium. In this example, the ROM 12 corresponds to the non-transitory tangible recording medium storing the program. Furthermore, the execution of this program results in the execution of a method corresponding to the program. Note that some or all of the functions executed by the CPU 11 may be configured as hardware using one or more ICs, etc. Furthermore, the number of microcomputers configuring the control unit 7 may be one or more.

[0022] The control unit 7 executes various processes based on inputs from the radar devices 3, 4, the vehicle speed sensor 5, and the yaw rate sensor 6, and controls the head-up display device 2. Specifically, the control unit 7 determines whether or not a vehicle in an adjacent lane on the left or right side of the host vehicle VH is approaching from behind the host vehicle VH, based on the detection results of the radar devices 3, 4, the vehicle speed sensor 5, and the yaw rate sensor 6. When it determines that a vehicle is approaching, the angle error estimation device 7 causes the head-up display device 2 to display a warning image indicating that a vehicle is approaching from behind on the left or right side.

[0023] The control unit 7 also functions as an angle error estimation device. The processing performed by the control unit 7 includes processing for estimating an angle error, which is an error in the observation azimuth angle θ observed by the radar devices 3 and 4. When the control unit 7 executes the processing for estimating an angle error, an angle error estimation method is executed.

[0024] 2, the left rear radar device 3 is installed at the left rear end of the host vehicle VH. The left rear radar device 3 is installed inside the vehicle bumper. The left rear radar device 3 detects surrounding vehicles present within the object detection region R1 by transmitting radar waves toward the rear of the host vehicle VH.

[0025] The right rear radar device 4 is installed at the right rear end of the host vehicle VH. The right rear radar device 4 is also installed inside the vehicle bumper. The right rear radar device 4 detects surrounding vehicles present within the object detection region R2 by transmitting radar waves toward the rear of the host vehicle VH.

[0026] The left rear radar device 3 is mounted so that the center axis CA1 of the object detection region R1 faces in a direction tilted by an angle φ to the rear left with respect to the width direction Dw of the vehicle VH. The right rear radar device 4 is mounted so that the center axis CA2 of the object detection region R2 faces in a direction tilted by an angle φ to the rear right with respect to the width direction Dw of the vehicle VH.

[0027] As described above, the radar devices 3 and 4 are installed closer to the vehicle interior than the bumper, and therefore the radar waves emitted from the radar devices 3 and 4 must pass through the bumper before being transmitted to the outside of the vehicle. If the surface of the bumper is curved, the radar waves are refracted by the bumper, which causes deviations in the transmitting and receiving directions of the radar waves, and this can result in an angular error between the angle at which an object exists and the observation azimuth angle θ observed by the radar devices 3 and 4.

[0028] Therefore, the control unit 7 corrects the observation azimuth angle θ acquired from the radar devices 3 and 4. Fig. 3 shows the process of correcting the observation azimuth angle θ by the control unit 7. The control unit 7 executes the process shown in Fig. 3 at a fixed cycle while the ignition switch is on. The fixed cycle is, for example, the modulation cycle T.

[0029] In Figure 3, first, in S10, which corresponds to the object detection information acquisition unit, observation point information is acquired from the radar devices 3 and 4. The observation point information is information about points on objects observed by the radar devices 3 and 4, and can also be called object detection information. Objects include moving objects and stationary objects. The object detection information includes the observation distance R, the observed relative velocity Vr, and the observation azimuth angle θ.

[0030] In S20, a tracking process is performed. The tracking process is a process of associating the object detected in S10 with the object detected one modulation cycle T before. Specifically, the control unit 7 performs the following process. Based on the observation point information acquired last time, the control unit 7 calculates a predicted position and predicted speed of the current observation point P corresponding to the previous observation point P. Note that the previous time means one modulation cycle T before. If the difference between the predicted position and predicted speed and the observed position and observed speed of the current observation point P is smaller than a predetermined upper limit position difference and upper limit speed difference, respectively, the control unit 7 determines that the current observation point P represents the same object as the previous observation point P.

[0031] In S30, which corresponds to the stationary object determination unit, a stationary object is extracted from the objects detected by the radar devices 3 and 4 based on the observation point information acquired in S10 and the speed v of the host vehicle VH. Specifically, the control unit 7 calculates v × cos θ as shown in FIG. 4. Then, the difference between the observed relative speed Vr of the object detected in S10 and v × cos θ is calculated. If the observation point P is a stationary object, the observed relative speed Vr should be the speed determined by the speed v of the host vehicle VH and the observation azimuth angle θ, i.e., v × cos θ. Therefore, if the absolute value of the difference between the observed relative speed Vr of the object detected in S10 and v × cos θ is close to 0, the observation point P is determined to be a stationary object.

[0032] In step S40, which corresponds to the first angle error estimator, a first angle error estimation process is executed. The first angle error estimation process is a process for estimating the angle errors of the radar devices 3 and 4 by the method disclosed in Patent Document 1. That is, the first angle error estimation process is a process for estimating the angle errors of the radar devices 3 and 4 for each azimuth angle by utilizing the azimuth angle dependency of the relative velocity Vr with respect to a stationary object. Details of step S40 are shown in FIG. 5.

[0033] In S41, it is determined whether the speed v of the host vehicle VH is greater than a speed threshold. The speed threshold is set to a value that allows the graph shown in FIG. 6 to have a sufficiently large slope. If the speed v of the host vehicle VH is greater than the speed threshold, the determination result in S41 is YES, and the process proceeds to S42. If the speed v of the host vehicle VH is equal to or less than the speed threshold, the determination result in S41 is NO. If the determination result in S41 is NO, the process of S40 is terminated.

[0034] In S42, a curve Cp is created that approximates the two-dimensional distribution of the observed relative velocity Vr and the observed azimuth angle θ based on the observation point information acquired from the radar devices 3 and 4. The Vr-θ curve Cp is created, for example, as follows: The two-dimensional distribution of the observed relative velocity Vr and the observed azimuth angle θ is averaged for each predetermined range (for example, 1 degree) of the observation azimuth angle θ. Then, a curve that approximates the points obtained by averaging is calculated. This curve is called the Vr-θ curve Cp.

[0035] In S43, a theoretical curve Ct representing the relationship between the observed relative velocity Vr detected for a stationary object and the observed azimuth angle θ is calculated using Equation 1 according to the velocity v of the host vehicle VH, where θinst is the mounting angle of the radar devices 3 and 4, a and A are constants, and N_FFT_BIN is the number of FFT points (e.g., 256). The number of FFT points means the number of points when the radar devices 3 and 4 analyze the sampling data using a fast Fourier transform (FFT).

[0036] In S44, the degree of approximation between the curve Cp created in S42 and the theoretical curve Ct created in S43 is calculated. In S45, it is determined whether the degree of approximation calculated in S44 is greater than a preset approximation threshold. If the degree of approximation is greater than the approximation threshold, the determination result in S45 is YES and the process proceeds to S46. If the degree of approximation is equal to or less than the approximation threshold, the determination result in S45 is NO. If the determination result in S45 is NO, the process of S40 ends.

[0037] In S46, an angle error estimate is calculated for each angle. To distinguish it from a second angle error estimate E2 (described later), the angle error estimate calculated in S46 is referred to as a first angle error estimate E1. The first angle error estimate E1 is the difference between the theoretical curve Ct and the curve Cp at the same observed relative velocity Vr. FIG. 6 shows an example of the first angle error estimate E1. In S47, the first angle error table is updated using the first angle error estimate E1 calculated for each angle in S46. For example, the currently calculated first angle error estimate E1 and the first angle error estimate E1 shown in the first angle error table are weighted and added for the same angle.

[0038] Returning to Fig. 3 for the explanation, after the first angle error estimation process is executed in S40, the process proceeds to S50, where the second angle error estimation process is executed. The second angle error estimation process is a process for estimating the angle errors of the radar devices 3 and 4 using the principle disclosed in Patent Document 2. Details of S50 are shown in Fig. 7.

[0039] In S51, the inclination of a stationary object is calculated. The inclination of a stationary object indicates the direction of movement of the stationary object as seen from the host vehicle VH. Therefore, the inclination of a stationary object can also be said to be the direction of movement of the stationary object. The processing of S51 is shown in detail in FIG. 8. In FIG. 8, in S51-1, the number of observations for each predetermined range of the observation azimuth angle θ described above is updated based on the observation azimuth angle θ at which the stationary object was extracted in S30.

[0040] In S51-2, it is determined whether the vehicle speed v of the host vehicle VH is greater than the first tilt determination value. If the determination result in S51-2 is NO, the processing of FIG. 8 is terminated. This is because when the speed v of the host vehicle VH is slow, the change in the distance to the stationary object becomes small, and the error in the tilt of the stationary object becomes large. On the other hand, if the determination result in S51-2 is YES, the processing proceeds to S51-3. In S51-3, it is determined whether the absolute value of the yaw rate ω of the host vehicle VH is smaller than the second tilt determination value. If the determination result in S51-3 is NO, the processing of FIG. 8 is also terminated. This is because when the absolute value of the yaw rate ω of the host vehicle VH is large, it becomes difficult to accurately eliminate the change in the azimuth angle of the stationary object due to the turning of the host vehicle VH. On the other hand, if the determination result in S51-3 is YES, the processing proceeds to S51-4.

[0041] In S51-4, the tilt of the stationary object is calculated. The method of calculating the tilt of the stationary object will be described with reference to Fig. 9. As shown in Fig. 9, in a coordinate system in which the radar device 3 is the origin, the traveling direction of the host vehicle VH is the X axis, and the direction perpendicular to the traveling direction is the Y axis, the X coordinate of the previous observation point P is calculated as x ｍ (t-1), the Y coordinate of the previous observation point P is y ｍ (t-1), the X coordinate of the current observation point P is x ｍ (t), the Y coordinate of this observation point P is y ｍ The observation point P is a point on a stationary object. Time t is the timing at which the second angle error estimation process is executed this time. Time (t-1) is the timing at which the second angle error estimation process was executed the previous time.

[0042] The X- and Y-components of the position change that occurs in the movement trajectory of the stationary object due to the vehicle VH turning are defined as Δx and Δy, respectively. ｍ The observation azimuth angle θ ｍ(t). When it is assumed that the vehicle VH is traveling straight, the observation azimuth angle θ as seen from the vehicle VH is ｍ The tilt of the stationary object at (t) can be calculated using Equation 2.

[0043] Δx and Δy are calculated from Equation 3 and Equation 4. Equation 3 and Equation 4 will now be described. As shown in Fig. 10, at time (t-1), a coordinate system CS1 is defined as a coordinate system having the radar device 3 as the origin, the traveling direction of the host vehicle VH as the X axis, and a direction perpendicular to the traveling direction as the Y axis. At time t, a coordinate system CS2 is defined as a coordinate system having the radar device 3 as the origin, the traveling direction of the host vehicle VH as the X axis, and a direction perpendicular to the traveling direction as the Y axis.

[0044] As shown in Figure 10, assume that the host vehicle VH travels at a traveling speed v and turns at a yaw rate ω between time (t-1) and time t. In this case, the host vehicle VH moves a distance equivalent to vT along the traveling direction at time (t-1), and travels a distance equivalent to vωT along a direction perpendicular to the traveling direction at time (t-1). ２ Furthermore, the host vehicle VH rotates in the horizontal plane by an angle equivalent to ωT.

[0045] If the X and Y coordinates of observation point P on a stationary object in coordinate system CS1 are x(t-1) and y(t-1), respectively, and the X and Y coordinates of observation point P on a stationary object in coordinate system CS2 are x(t) and y(t), respectively, then equations 3 and 4 hold. ωTy(t) in equation 3 corresponds to Δx, and the right-hand side of equation 4 corresponds to Δy.

[0046]

[0047] Δx is calculated from ωTy(t), and Δy is calculated from the right side of Equation 4. The calculated Δx and Δy and the X coordinate x of the previous observation point P are used ｍ (t-1), Y coordinate y ｍ (t-1), the X coordinate of the current observation point P, x ｍ (t), Y coordinate y ｍ (t) into Equation 2, and obtain the observation azimuth angle θ of the previous observation point P. ｍ Calculate the tilt of a stationary object at

[0048] In S51-5, the stationary object tilt calculated in S51-4 is compared with the radar device (i.e., radar device 3 or radar device 4) that detected the observation point P corresponding to the stationary object tilt, and the observation azimuth angle θ ｍ (t) and stored in the RAM 13, and the stationary object tilt calculation process is terminated. Here, m is an integer. Therefore, the stationary object tilt is calculated by the observation azimuth angle θ ｍ Associating the tilt angle of the stationary object with (t) means classifying the tilt angle of the stationary object in units of one degree of the observation azimuth angle θ.

[0049] Returning to Fig. 7 for the explanation, in S52, which corresponds to the average calculation unit, the stationary object tilts classified by the observation azimuth angle θ are averaged for each classification of the observation azimuth angle θ to update the average value of the stationary object tilts. Specifically, for the multiple stationary object tilts stored in the processing of S51 between the end of the previous second angle error estimation processing and the start of the current second angle error estimation processing, the average value of the stationary object tilts is calculated for each observation azimuth angle θ. For example, ｍ When N stationary object tilts are stored, the control unit 7 divides the sum of the N stationary object tilts by N and calculates the result as the observation azimuth angle θ ｍ The inclination of the stationary object is calculated as the average value.

[0050] In S53, an angle error estimation process is executed. The angle error estimation process is shown in detail in FIG. 11. In S53-1, a valid continuous interval is set. Specifically, the control unit 7 sets the range of observation azimuth angles θ in which the number of observations is equal to or greater than a preset valid determination value (e.g., 500) as the valid continuous interval. The valid determination value means the required number of observations.

[0051] In S53-2, the control unit 7 determines whether the valid continuous section is valid. Specifically, the control unit 7 determines whether the section length of the valid continuous section is equal to or greater than a preset valid continuous judgment value (e.g., 10°). If the section length is equal to or greater than the valid continuous judgment value, the control unit 7 determines that the valid continuous section is valid. If the control unit 7 determines that the valid continuous section is not valid (S53-2: NO), the angle error estimation process ends. If the control unit 7 determines that the valid continuous section is valid (S53-2: YES), the process proceeds to S53-3.

[0052] In S53-3, the first angle command value n stored in the RAM 13 is set to 0. In the following S53-4, a first maximum angle command value K is set. Specifically, the control unit 7 calculates the angle θ between the end angle of the valid continuous section and the start angle of the valid continuous section. ０ The value obtained by subtracting the above is set as the first maximum angle command value K.

[0053] S53-5 and S53-6 correspond to the distance calculation unit. In S53-5, the start angle θ ０ The first angle error estimate E1(θ ０ ) is obtained. Then, the first angle error estimate E1(θ ０ ) at the start angle θ of the effective continuous section ０ The second angle error estimate E2 is set at the start angle θ of the valid continuous section. ０ Radial distance r at ０ is calculated from Equation 5.

[0054] In S53-6, the observation azimuth angle θ ｎ＋１ Radial distance r at ｎ＋１ is calculated using Equation 6. Observation azimuth angle θ ｎ＋１ is the observation azimuth angle θ ｎ The radial distance r is the next azimuth angle obtained by adding 1, which is the unit azimuth angle, to the radius distance r. ｎ＋１ is the next distance, which means the distance to the stationary object at the next azimuth angle. α in Equation 5 is the observation azimuth angle θ ｎ is the average tilt of stationary objects at

[0055] As shown in FIG. 12, Equation 6 determines whether a line extending from the previously calculated point CP1 with a gradient of α has an observation azimuth angle θ ｎ＋１ This corresponds to calculating the point CP2 where the line intersects with the line in the direction of the arrow.

[0056] In S53-7, the control unit 7 calculates the radius distance r ｎ＋１ is the radial distance r ｎ Determine whether the radius distance r is longer than the ｎ＋１ is the radial distance r ｎ If the result of the determination in S53-7 is YES, the process proceeds to S53-8.

[0057] In step S53-8, which corresponds to the second angle error estimating unit, the control unit 7 calculates the second angle error estimated value E2. Specifically, the control unit 7 first calculates the true angle estimated value θ ｔｒｕｅ is calculated. Formula 7 will be explained. The line segment connecting the left rear radar device 3 and point CP2 is rotated around the left rear radar device 3 as a fulcrum so that point CP2 is located on a line L1 drawn through CP1 and parallel to the straight-ahead direction of the host vehicle VH, as shown by line L2 in FIG. 12. Line L1 is a line indicating the reference moving direction in which a stationary object moves when the host vehicle VH is moving straight and there is no angle error. Therefore, the angle of line L2 is the true angle estimate θ, which is an estimate of the azimuth angle of the stationary object detected by the radar device 3 when there is no angle error. ｔｒｕｅ becomes.

[0058] Furthermore, in S53-8, the observation azimuth angle θ ｎ＋１ From the true angle estimate θ ｔｒｕｅ The control unit 7 then stores the calculated second angle error estimate E2 in the RAM 13 in association with the observation azimuth angle θ.

[0059] In S53-9, the control unit 7 increments the first angle command value n. That is, it adds 1 to n. In S53-10, the control unit 7 determines whether the first angle command value n is equal to or greater than the first maximum angle command value K. If the first angle command value n is less than the first maximum angle command value K, the determination result in S53-10 becomes NO, and the process returns to S53-6. On the other hand, if the first angle command value n is equal to or greater than the first maximum angle command value K, the control unit 7 ends the process in FIG. 11 and proceeds to S54 in FIG. 7.

[0060] In S54 of Fig. 7, the control unit 7 updates the second angle error table. Specifically, the control unit 7 first converts the observation azimuth angle θ observed by the radar device 3 into an angle centered around the central axis CA1 of the radar device 3. The control unit 7 also converts the observation azimuth angle θ observed by the radar device 4 into an angle centered around the central axis CA2 of the radar device 4. The control unit 7 then updates the second angle error table by associating the angle error calculated in S53 with each converted observation azimuth angle θ. This ends the second angle error estimation process in S50, and the process proceeds to S60 of Fig. 3.

[0061] In step S60, which corresponds to the angular error integration estimation unit, an angular error integration process is executed. The angular error integration process is a process of integrating the first angular error estimate E1 estimated in step S40 and the second angular error estimate E2 estimated in step S50. Details of the angular error integration process are shown in FIG. 13.

[0062] 13 , in S61, it is determined whether the observation azimuth angle θ is smaller than a first angle threshold TH1. The first angle threshold TH1 is the lower limit of the azimuth angle range in which the estimation accuracy of the first angle error estimate E1 and the second angle error estimate E2 is similar. The first angle threshold TH1 is, for example, directly in front of the radar devices 3 and 4, i.e., 0 degrees. If the determination result in S61 is YES, the process proceeds to S62. In S62, it is determined that mode 1 is selected for the observation azimuth angle θ determined in S61. Mode 1 is a mode applied to an observation azimuth angle θ that is perpendicular to the traveling direction of the host vehicle HV, rather than the azimuth angle range in which the estimation accuracy of the first angle error estimate E1 and the estimation accuracy of the second angle error estimate E2 are similar. In mode 1, the first angle error estimate E1 is used to correct the angle error.

[0063] If the determination result in S61 is NO, the process proceeds to S63. In S63, it is determined whether the observation azimuth angle θ is greater than a second angle threshold TH2. The second angle threshold TH2 refers to the upper limit of the azimuth angle range in which the estimation accuracy of the first angle error estimate E1 and the second angle error estimate E2 is similar. In the case of a radar device 3 installed so that the angle directly to the side of the vehicle is -50 degrees and the angle directly behind the vehicle is 40 degrees, the second angle threshold TH2 is, for example, 20 degrees. If the determination result in S63 is YES, the process proceeds to S64. In S64, it is determined that mode 2 is to be selected for the observation azimuth angle θ determined in S63. Mode 2 is a mode applied to an observation azimuth angle θ that is further rearward in the traveling direction of the host vehicle HV than the azimuth angle range in which the estimation accuracy of the first angle error estimate E1 and the estimation accuracy of the second angle error estimate E2 are similar. In mode 2, the second angle error estimate E2 is used to correct the angle error.

[0064] If the determination result in S63 is NO, the process proceeds to S65. In S65, it is determined that mode 3 is to be selected for the observation azimuth angle θ determined in S63. Mode 3 is a mode that is selected when the observation azimuth angle θ is within the azimuth angle range in which the estimation accuracy of the first angle error estimate value E1 and the second angle error estimate value E2 is similar.

[0065] In mode 3, the first angle error estimate E1 and the second angle error estimate E2 are weighted and added together for use in correcting the angle error. For example, the third angle error estimate E3 is determined using the following equation 8. Equation 8 determines the third angle error estimate E3 by weighting the first angle error estimate E1 and the second angle error estimate E2 so that the weight of the first angle error estimate E1 increases as the observation azimuth angle θ approaches a direction perpendicular to the traveling direction of the host vehicle VH.

[0066] E3 = (1 - k) x E1 + k x E2 (Equation 8) k = (observation azimuth angle θ - TH1) / (TH2 - TH1) If any of S62, S64, and S65 has been executed, the process proceeds to S66. In S66, it is determined whether or not a mode has been determined for all observation azimuth angles θ. All observation azimuth angles θ are, for example, -90 degrees to 90 degrees. If the determination result in S66 is YES, the process proceeds to S67. In S67, n, which indicates the observation azimuth angle θ, is incremented by 1. Thereafter, the process returns to S61. On the other hand, if the determination result in S66 is YES, the process of S60 is terminated. After the process of S60 is terminated, the process proceeds to S70 in FIG. 3.

[0067] In S70, which corresponds to the angle correction unit, angle correction is performed. Specifically, the observation azimuth angle θ indicated by the observation point information acquired for object detection in S10 is corrected according to the mode determined in the angle error integration process in S60. For example, if mode 2 is selected for the observation azimuth angle θ, the second angle error estimate value E2 corresponding to that observation azimuth angle θ is extracted from the second angle error table, and the extracted second angle error estimate value E2 is added to the observation azimuth angle θ to correct the observation azimuth angle θ. The angle correction in S70 is performed for all objects.

[0068] Here, angle correction in mode 2 will be described with reference to Fig. 14. In Fig. 14, the black circle indicates the observation point P, and the diamond indicates the start angle θ of the effective continuous section as in Patent Document 2. ０ 14 shows the position of observation point P after correction when the angular error in mode 2 is set to zero.

[0069] In Patent Document 2, the start angle θ of the effective continuous section ０ The angle error of the observation point P is set to zero. Then, the observation point P is set to the start angle θ of the effective continuous section. ０ The starting angle θ of the effective continuous section is corrected to a straight line L11 that passes through the line L11 and is parallel to the traveling direction of the host vehicle VH. ０ If the angular error is not actually zero, the accuracy of the correction will be reduced.

[0070] On the other hand, in mode 2, the starting angle θ in the first angle error table ０The first angle error estimate E1 is calculated based on the start angle θ of the valid continuous section. ０ The first angle error estimate E1 is an erroneous estimate obtained by the method disclosed in Patent Document 1. The method disclosed in Patent Document 1 reduces the accuracy of the angle error estimate as the stationary object moves away from the host vehicle VH. However, in other words, the method disclosed in Patent Document 1 provides good accuracy in the error estimate when the stationary object is close to the host vehicle VH. The start angle θ of the valid continuous section is ０ The position of the stationary object when the start angle θ of the effective continuous section is near the vehicle VH. ０ This allows for accurate correction that also reflects the angle error at the time of measurement.

[0071] In S80, it is determined whether the ignition switch is turned off. If the determination result in S80 is NO, the process returns to S10 and continues from S10 onwards. On the other hand, if the determination result in S80 is YES, the process shown in FIG. 3 is terminated.

[0072] The effects of the embodiment described above will now be described. The control unit 7 executes a first angle error estimation process in S40 and a second angle error estimation process in S50. The control unit 7 then estimates the angle error of the object detected by the radar devices 3 and 4 using one or both of the first angle error estimate value E1 and the second angle error estimate value E2 depending on the observation azimuth angle θ.

[0073] Since the angle error estimation methods used in the first angle error estimation process (S40) and the second angle error estimation process (S50) are different, the first angle error estimated value E1 and the second angle error estimated value E2 are not necessarily the same even if they are angle errors for the same observation azimuth angle θ.

[0074] The control unit 7 uses one of the angle error estimates under conditions where the accuracy of the other angle error estimate decreases, or uses the other angle error estimates in combination. Specifically, the control unit 7 selects mode 3 for the azimuth angle range in which the estimation accuracy of the first angle error estimate E1 and the estimation accuracy of the second angle error estimate E2 are similar (S65). In mode 3, the first angle error estimate E1 and the second angle error estimate E2 are weighted so that the weight of the first angle error estimate E1 increases as the azimuth angle approaches a direction perpendicular to the traveling direction of the host vehicle VH, and the third angle error estimate E3 is determined.

[0075] Furthermore, the control unit 7 selects mode 1 when estimating the angular error of the observation azimuth angle θ, which is in a direction perpendicular to the traveling direction of the host vehicle VH, beyond the azimuth angle range in which the estimation accuracy of the first angle error estimate value E1 and the estimation accuracy of the second angle error estimate value E2 are similar (S62). In mode 1, the angular error of the observation azimuth angle θ is set as the first angle error estimate value E1. Furthermore, the control unit 7 selects mode 2 when estimating the angular error of the observation azimuth angle θ, which is in a direction further rearward in the traveling direction of the host vehicle VH than the azimuth angle range in which the estimation accuracy of the first angle error estimate value E1 and the estimation accuracy of the second angle error estimate value E2 are similar (S64). In mode 2, the angular error of the observation azimuth angle θ is set as the second angle error estimate value E2. This allows the angular errors of the radar devices 3 and 4 to be estimated with higher accuracy.

[0076] The control unit 7 also determines a start angle θ at which estimation of the second angle error estimate E2 starts. ０ Distance to a stationary object at (r ０ ) at the starting angle θ ０ and the starting angle θ ０ The first angle error estimate E1(θ ０ ) (S53-5).

[0077] As described with reference to FIG. 11, the second angle error estimate E2 is estimated based on the radial distance r ｎ＋１ is required. And the radial distance r ｎ＋１ To calculate this, the observation azimuth angle θ ｎ Radial distance r at ｎThat is, in order to estimate the second angle error estimated value E2, a start angle θ at which the estimation of the second angle error estimated value E2 starts is required. ０ Radial distance r at ０ is necessary.

[0078] Starting angle θ ０ is closest to the direction perpendicular to the traveling direction of the host vehicle HV within the angle range for estimating the second angle error estimate E2. The first angle error estimate E1 is more accurate as the stationary object is closer to the direction perpendicular to the traveling direction of the host vehicle VH. Therefore, the start angle θ ０ Radial distance r at ０ By using the first angle error estimate E1 to calculate the radial distance r ０ The radial distance r can be calculated with high accuracy. ０ The accuracy of the subsequent radial distance r ｎ Therefore, according to this embodiment, the estimation accuracy of the second angle error estimate value E2 is improved for all observation azimuth angles θ at which the second angle error estimate value E2 is estimated.

[0079] The control unit 7 corrects (S70) the observation azimuth angle θ of the object observed by the radar devices 3 and 4 based on the angle error estimated value obtained by the angle error integration process (S60). In this way, subsequent control such as displaying a warning image can be performed based on the corrected observation azimuth angle θ.

[0080] Although the embodiments have been described above, the disclosed technology is not limited to the above-described embodiments, and the following modifications are also included within the scope of the disclosure. Furthermore, various modifications other than those described below can be implemented without departing from the spirit of the invention. In the following description, elements having the same reference numerals as those used up to that point are the same as the elements having the same reference numerals in the previous embodiments, unless otherwise specified. Furthermore, when only a portion of the configuration is described, the previously described embodiment can be applied to the other portions of the configuration.

[0081] [Variation 1] In the above-described embodiment, if the difference between the first angle error estimate E1 and the second angle error estimate E2 estimated for the same observation azimuth angle θ is equal to or greater than the error threshold, the first angle error estimate E1 and the second angle error estimate E2 may be invalidated for all observation azimuth angles θ. This is because if the difference between the first angle error estimate E1 and the second angle error estimate E2 estimated for the same observation azimuth angle θ is equal to or greater than the error threshold, there is a possibility that the estimation accuracy of one or both of the first angle error estimate E1 and the second angle error estimate E2 is poor.

[0082] [Variation 2] In this embodiment, the number of observations of stationary objects is counted for each observation azimuth angle (S51-1), and the average value of the stationary object tilts is calculated for each observation azimuth angle (S52). This average value of the stationary object tilts is used to calculate the second angle error estimate E2. However, the range of observation azimuth angles θ in which the number of observations is equal to or greater than the validity determination value (i.e., the required number) is set as a valid continuous interval, and if this valid continuous interval is valid, the start angle θ of the valid continuous interval is set as ０ is the starting angle θ for calculating the second angle error estimate E2. ０ (S53). Therefore, in the embodiment, the start angle θ ０ The second angle error estimate E2 is not calculated for angles smaller than

[0083] On the other hand, in this Modification 2, the control unit 7 executes the following processing as the average calculation unit. That is, if the number of observations of stationary objects for each observation azimuth angle classification does not exceed the required number, the number of observations of stationary objects in multiple adjacent observation azimuth angle classifications is added together to make the total number equal to or greater than the required number. Then, the stationary object inclinations calculated from the number of observations of stationary objects that exceeds the required number are averaged to calculate a multi-angle stationary object inclination average value. Because the stationary object inclination average value is the stationary object moving direction average value, the multi-angle stationary object inclination average value can also be referred to as a multi-angle moving direction average value.

[0084] Furthermore, as a process of the distance calculation unit, for the observation azimuth angle θ for which the stationary object tilt average value at multiple angles has been calculated, the control unit 7 calculates the next distance, the radial distance r using the stationary object tilt average value at multiple angles as α instead of the stationary object tilt average value. ｎ＋１In this way, it is possible to reduce the number of observation azimuth angles θ for which the second angle error estimate value E2 is not calculated.

[0085] The number of observation azimuth angles θ for summing up the number of observations of stationary objects to calculate the multiple-angle stationary object tilt average value may be set in advance, for example, to three angles. In addition, when the multiple-angle stationary object tilt average value is used, the observation azimuth angle θ for which the multiple-angle stationary object tilt average value is calculated is the start angle θ for calculating the second angle error estimate value E2. ０ In this case, the starting angle θ ０ Radial distance r ０ Calculate.

[0086] [Variation 3] In the embodiment, the range of the observation azimuth angle θ in which the number of observations is equal to or greater than the validity judgment value is set as a valid continuous interval, and if the valid continuous interval is valid, the second angle error estimate value E2 is calculated for the observation azimuth angle θ within the valid continuous interval.

[0087] On the other hand, in this modification 3, no effective continuous section is set. ｎ＋１ For each of the observations, it is determined whether the number of observations is equal to or greater than the validity determination value. If the number of observations is equal to or greater than the validity determination value, the radial distance r ｎ＋１ If the number of observations is less than the validity threshold, the radial distance r ｎ＋１ to 1 / cosθ ｎ＋１ In other words, if the number of observations is less than the validity threshold, the observation azimuth angle θ ｎ＋１ In this way, when a valid continuous interval is set, the angle error at the observation azimuth angle θ is not included in the valid continuous interval, and as a result, the second angle error estimate value E2 can be estimated even for the observation azimuth angle θ for which the second angle error estimate value E2 cannot be estimated.

[0088] (Disclosure of Technical Ideas) This specification discloses several technical ideas described in the following sections. Also included in the disclosure are computer programs, methods, and recording media on which computer programs are recorded, which correspond to the following technical ideas. Some sections may be written in a multiple dependent form, with the subsequent section alternatively referring to the preceding section. Furthermore, some sections may be written in a multiple dependent form, with the subsequent section alternatively referring to another multiple dependent section. These multiple dependent sections define several technical ideas. (Technical Idea 1) An angle error estimation device (7) is mounted on a moving body (VH) and estimates an angle error, which is an error in an observation azimuth angle observed by at least one radar device (3, 4) whose detection area includes a side of the moving body, comprising: an object detection information acquisition unit (S10) that acquires object detection information including a distance (R) from the radar device to an object present in the detection area, an observation azimuth angle (θ) of the object, and a relative speed (Vr) of the object; a stationary object determination unit (S30) that determines whether the object is a stationary object based on the observation azimuth angle of the object, the relative speed, and the speed of the moving body; and a first angle error estimation unit (S40) that determines a first angle error estimate value (E1) that estimates the angle error for each observation azimuth angle of the radar device by utilizing the azimuth angle dependency of the relative speed with respect to the stationary object. a movement direction calculation unit (S51) that calculates, for each observation azimuth angle at which the radar device observes the stationary object, a stationary object movement direction that is a direction in which the stationary object moves as seen from the moving object when the moving object is assumed to be moving straight, based on the object detection information of the stationary object determined by the stationary object determination unit and moving object trajectory information that specifies the movement trajectory of the moving object; an average calculation unit (S52) that calculates an average movement direction value (α) by averaging the multiple stationary object movement directions classified by the observation azimuth angle, for each classification of the observation azimuth angle; and a calculation unit (S53) that calculates a value between the average movement direction value at the observation azimuth angle and the distance (r) to the stationary object at the observation azimuth angle.ｎ ) based on the observation azimuth angle and the unit azimuth angle added to the observation azimuth angle, the next distance (r ｎ＋１ a distance calculation unit (S53-5, S53-6) that calculates a true angle estimation value (θ ｔｒｕｅ ) and determines a second angle error estimate (E2) that estimates the angle error for each observation azimuth angle of the radar device based on the difference between the true angle estimate and the next azimuth angle, and an angle error integrated estimation unit (S60) that estimates the angle error of the object detected by the radar device using one or both of the first angle error estimate and the second angle error estimate. (Technical Idea 2) The distance calculation unit (S53-5) calculates the distance (r ０) based on the start angle and the first angle error estimate at the start angle. (Technical Idea 3) The angle error estimation device according to Technical Idea 1 or 2, wherein the angle error integrated estimation unit estimates the angle error by weighting the first angle error estimate and the second angle error estimate within an azimuth angle range in which the estimation accuracy of the first angle error estimate and the estimation accuracy of the second angle error estimate are similar, such that the weight of the first angle error estimate increases as the azimuth angle approaches a direction perpendicular to the traveling direction of the moving object. (Technical Idea 4) The angle error estimation device according to Technical Idea 3, wherein the angle error integrated estimation unit sets the angle error of the observation azimuth angle that is in a direction perpendicular to the traveling direction of the moving body relative to an azimuth angle range in which the estimation accuracy of the first angle error estimate and the estimation accuracy of the second angle error estimate are similar as the first angle error estimated value, and sets the angle error of the observation azimuth angle that is behind the traveling direction of the moving body relative to an azimuth angle range in which the estimation accuracy of the first angle error estimate and the estimation accuracy of the second angle error estimate are similar as the second angle error estimated value. (Technical Idea 5) The angle error estimation device according to any one of Technical Ideas 1 to 4, wherein the angle error integrated estimation unit invalidates the first angle error estimated value and the second angle error estimated value when a difference between the first angle error estimated value and the second angle error estimated value, both estimated for the same observation azimuth angle, is equal to or greater than an error threshold. (Technical Idea 6) The angle error estimation device according to any one of Technical Ideas 1 to 5, wherein the average calculation unit, when the number of observations of the stationary objects for each observation azimuth angle classification is equal to or greater than a required number, calculates the moving direction average value for each observation azimuth angle classification, and, when the number of observations of the stationary objects for each observation azimuth angle classification does not exceed the required number, adds up the numbers of observations of the stationary objects in a plurality of adjacent observation azimuth angle classifications to equal to or greater than the required number, and calculates a multi-angle moving direction average value by averaging the stationary object moving directions calculated from the number of observations of the stationary objects equal to or greater than the required number, and the distance calculation unit calculates the next distance using the multi-angle moving direction average value instead of the moving direction average value for the observation azimuth angle for which the multi-angle moving direction average value has been calculated.(Technical Idea 7) The angle error estimation device according to any one of Technical Ideas 1 to 6, further comprising an angle correction unit that corrects the observation azimuth angle of the object observed by the radar device based on the angle error estimated by the angle error integrated estimation unit.

[0089] In this disclosure and claims, the term "processor" refers to one or more hardware processors configured to execute the processing defined by computer program code (i.e., one or more instructions of a computer program) included in a computer program by loading the computer program code each time. In other words, a "processor" is a hardware device that executes one or more programmed processes. Therefore, computer program code can also be considered software that can define the processing of the processor depending on its content. A "processor" may be a general-purpose or special-purpose processor, such as, but not limited to, a CPU, a microprocessor, a GPU, and a DFP (Data Flow Processor).

[0090] In this disclosure and in the claims, the term "memory" refers to one or more hardware memories that are non-transitory tangible recording media configured to store computer program code and / or data accessible to a processor. The "memory" may be implemented using memory technologies such as SRAM, SDRAM, non-volatile / flash-type memory, or other types of memory. Computer program code constituting a program may be stored in the memory and executed by a processor to cause the processor to perform the various functions described above.

[0091] In this disclosure and in the claims, the term "circuit" refers to one or more hardware logic circuits configured to perform specific processing based on a predesigned circuit configuration. In other words (and in contrast to "processor"), a "circuit" in this disclosure and in the claims refers to a hardware device that performs specific processing based on circuit configuration, rather than processing defined by software such as computer program code. For example, a "circuit" may include custom ICs such as ASICs (Application Specific Integrated Circuits) and FPGAs (Field Programmable Gate Arrays) designed using a Hardware Description Language (HDL). In other words, a "circuit" in this disclosure and in the claims includes all hardware circuits except for the processor, which executes processing by loading computer program code.

[0092] It should be noted that in this disclosure or in the claims, the phrase "at least one of a processor and a circuit" should be interpreted as a disjunction (logical OR), and not as at least one processor and at least one circuit.

Claims

1. An angle error estimation device (7) mounted on a moving body (VH) for estimating an angle error, which is an error in an observation azimuth angle observed by at least one radar device (3, 4) whose detection area includes a side of the moving body, comprising: an object detection information acquisition unit (S10) for acquiring object detection information including a distance (R) from the radar device to an object present in the detection area, an observation azimuth angle (θ) of the object, and a relative speed (Vr) of the object; a stationary object determination unit (S30) for determining whether the object is a stationary object based on the observation azimuth angle of the object, the relative speed, and the speed of the moving body; and a first angle error estimation unit (S40) for determining a first angle error estimate value (E1) obtained by estimating the angle error for each observation azimuth angle of the radar device using the azimuth angle dependency of the relative speed with respect to the stationary object. a movement direction calculation unit (S51) that calculates, for each observation azimuth angle at which the radar device observes the stationary object, a stationary object movement direction that is a direction in which the stationary object moves as seen from the moving object when the moving object is assumed to be moving straight, based on the object detection information of the stationary object determined by the stationary object determination unit and moving object trajectory information that specifies the movement trajectory of the moving object; an average calculation unit (S52) that calculates an average movement direction value (α) by averaging the multiple stationary object movement directions classified by the observation azimuth angle, for each classification of the observation azimuth angle; and a calculation unit (S53) that calculates a value between the average movement direction value at the observation azimuth angle and the distance (r) to the stationary object at the observation azimuth angle. ｎ ) based on the observation azimuth angle and the unit azimuth angle added to the observation azimuth angle, the next distance (r ｎ＋１ a distance calculation unit (S53-5, S53-6) that calculates a true angle estimation value (θ ｔｒｕｅ and determining a second angle error estimate (E2) that estimates an angle error for each observation azimuth angle of the radar device based on the difference between the true angle estimate and the next azimuth angle; and an angle error integrated estimation unit (S60) that estimates an angle error of the object detected by the radar device using one or both of the first angle error estimate and the second angle error estimate.

2. The distance calculation unit (S53-5) calculates the distance (r ０ 2. The angular error estimation device according to claim 1, wherein the angular error estimation unit 100 calculates the angular error (Eq. (1)) based on the start angle and the first angular error estimate value at the start angle.

3. The angle error estimation device according to claim 1, wherein the angle error integrated estimation unit estimates the angle error by weighting the first angle error estimation value and the second angle error estimation value so that the weight of the first angle error estimation value becomes heavier as the azimuth angle approaches a direction perpendicular to the traveling direction of the moving body, within an azimuth angle range in which the estimation accuracy of the first angle error estimation value and the estimation accuracy of the second angle error estimation value are similar.

4. The angle error estimation device according to claim 3, wherein the angle error integrated estimation unit determines, as the first angle error estimate, the angle error of the observation azimuth angle that is in a direction perpendicular to the traveling direction of the moving body, beyond the azimuth angle range in which the estimation accuracy of the first angle error estimate and the estimation accuracy of the second angle error estimate, and determines, as the second angle error estimate, the angle error of the observation azimuth angle that is further to the rear of the traveling direction of the moving body, beyond the azimuth angle range in which the estimation accuracy of the first angle error estimate and the estimation accuracy of the second angle error estimate, 5. The angle error estimation device according to claim 1, wherein the angle error integrated estimation unit invalidates the first angle error estimation value and the second angle error estimation value on the basis that the difference between the first angle error estimation value and the second angle error estimation value estimated for the same observation azimuth angle is equal to or greater than an error threshold value.

6. The angle error estimation device according to claim 1, wherein the average calculation unit, when the number of observations of the stationary objects for each observation azimuth angle classification is equal to or greater than a required number, calculates the moving direction average value for each observation azimuth angle classification, and, when the number of observations of the stationary objects for each observation azimuth angle classification does not exceed the required number, adds up the numbers of observations of the stationary objects in a plurality of adjacent observation azimuth angle classifications to equal to or greater than the required number, and calculates a multi-angle moving direction average value by averaging the stationary object moving directions calculated from the number of observations of the stationary objects equal to or greater than the required number, and the distance calculation unit calculates the next distance for the observation azimuth angle for which the multi-angle moving direction average value has been calculated, using the multi-angle moving direction average value instead of the moving direction average value.

7. The angular error estimation device according to claim 1, further comprising an angle correction unit that corrects the observation azimuth angle of the object observed by the radar device based on the angular error estimated by the angular error integrated estimation unit.

8. An angle error estimation method for estimating an angle error, which is an error in an observation azimuth angle observed by at least one radar device (3, 4) mounted on a moving body (VH) and having a detection area that includes a side of the moving body, comprising: acquiring object detection information from the radar device, the object detection information including a distance (R) to an object present in the detection area, an observation azimuth angle (θ) of the object, and a relative speed (Vr) of the object (S10); determining whether the object is a stationary object based on the observation azimuth angle of the object, the relative speed, and the speed of the moving body (S30); determining a first angle error estimate (E1) by estimating the angle error for each observation azimuth angle of the radar device using the azimuth angle dependency of the relative speed with respect to the stationary object (S40); Based on the object detection information of the stationary object and moving object trajectory information that specifies the movement trajectory of the moving object, a stationary object movement direction, which is the direction in which the stationary object moves as seen from the moving object when the moving object is assumed to be moving straight, is calculated for each observation azimuth angle at which the radar device observed the stationary object (S51), an average movement direction value (α) is calculated by averaging the multiple stationary object movement directions classified by the observation azimuth angle for each classification of the observation azimuth angle (S52), and a value obtained by averaging the average movement direction value at the observation azimuth angle and the distance (r) to the stationary object at the observation azimuth angle is calculated. ｎ ) based on the observation azimuth angle and the unit azimuth angle added to the observation azimuth angle, the next distance (r ｎ＋１ ) is calculated (S53-5, S53-6), and a true angle estimate (θ ｔｒｕｅ ), and determine a second angle error estimate (E2) that estimates the angle error for each observation azimuth angle of the radar device based on the difference between the true angle estimate and the next azimuth angle (S53-8); and estimate the angle error of the object detected by the radar device using one or both of the first angle error estimate and the second angle error estimate.

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