Moving object detection device

Abstract

The present invention provides a mobile object detection device (4) that estimates a tracking trajectory of a mobile object corresponding to a plurality of observation points based on observation point positions represented by a plurality of observation point information acquired at different times. The mobile object detection device stores a maximum receiving power based on the receiving powers represented by the plurality of observation point information. The mobile object detection device determines whether a receiving power difference obtained by subtracting the receiving power represented by the acquired observation point information from the maximum receiving power is greater than a reduction judgment value. The mobile object detection device determines whether the receiving power represented by the acquired observation point information is below an identification judgment value. When the mobile object detection device determines that the receiving power difference is greater than the reduction judgment value and the receiving power is below the identification judgment value, the mobile object detection device suppresses the degree of following the observation point in the tracking trajectory.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This international application claims the priority based on Japanese Patent Application No. 2018-136958 filed with the Japan Patent Office on July 20, 2018, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present disclosure relates to a moving object detection device that detects a moving object existing around a vehicle. Background Art

[0004] Patent Document 1 describes a moving object detection device that irradiates a predetermined angle range around a vehicle with radar waves as transmission waves and receives reflected waves, thereby detecting a moving object existing around the vehicle.

[0005] Patent Document 1: Japanese Patent Application Publication No. 2011-17634

[0006] In a radar device, due to the multipath caused by the road surface and roadside objects, the received power of the radar wave reflected by the detection object is sometimes reduced when the radar device is used to receive the radar wave, and the SN ratio is reduced. The inventor's detailed research results have found the following problem: when the SN ratio is reduced, the detection result of the direction of the detection object is biased, and the detection accuracy of the position of the detection object is reduced. Summary of the invention

[0007] The present disclosure improves the accuracy of position detection of a moving object.

[0008] One aspect of the present disclosure is a moving object detection device including an information acquisition unit, a trajectory estimation unit, a maximum power storage unit, a power reduction determination unit, a recognition determination unit, and a suppression unit.

[0009] The information acquisition unit is configured to repeatedly acquire observation point information from a radar device mounted on the vehicle and transmitting and receiving radar waves, wherein the observation point information at least indicates the observation point position, which is the position of the observation point reflecting the radar wave, and the received power, which is the power of the received radar wave.

[0010] The trajectory estimating unit is configured to estimate a tracking trajectory that follows the movement of the mobile object corresponding to the plurality of observation points based on the observation point positions indicated by the plurality of observation point information acquired by the information acquiring unit at different times.

[0011] The maximum power storage unit is configured to store a maximum received power which is a maximum value of the received powers based on the received powers indicated by the plurality of observation point information acquired by the information acquisition unit at different times.

[0012] The power reduction determination unit is configured to determine whether a reception power difference is greater than a preset reduction determination value, wherein the reception power difference is a subtraction value obtained by subtracting the reception power indicated by the observation point information acquired by the information acquisition unit from the maximum reception power stored in the maximum power storage unit.

[0013] The identification determination unit is configured to determine whether the received power indicated by the observation point information acquired by the information acquisition unit is equal to or less than a preset identification determination value.

[0014] The suppressing unit is configured to suppress the degree of following the observation point in the following trajectory estimated by the trajectory estimating unit when the power reduction determining unit determines that the received power difference is larger than the reduction determination value and the recognition determining unit determines that the received power is less than the recognition determination value.

[0015] For the mobile object detection device of the present disclosure constructed in this way, when it is judged that the received power difference ratio is greater than the reduction judgment value, and when it is judged that the received power is below the recognition judgment value, it is judged that the SN ratio is reduced. Moreover, for the mobile object detection device of the present disclosure, when it is judged that the SN ratio is reduced, the degree of following the observation point in the following trajectory estimated by the trajectory estimation unit is suppressed. When the SN ratio is reduced, the position detection accuracy of the observation point detected is low, so the mobile object detection device of the present disclosure can suppress the influence of the observation point with low position detection accuracy, estimate the following trajectory of the mobile object, and improve the position detection accuracy of the mobile object. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a block diagram showing the configuration of a moving object detection system.

[0017] Figure 2 This is a diagram showing the installation position of the radar device and the object detection area.

[0018] Figure 3 This is a flowchart showing the first half of the rear approach warning process.

[0019] Figure 4 This is a flowchart showing the second half of the rear approach warning process.

[0020] Figure 5 is a diagram showing a follow-up area.

[0021] Figure 6 This is a diagram showing a portion where the SN ratio is reduced due to multipath.

[0022] Figure 7 It is a diagram showing the received power difference and the identification decision value.

[0023] Figure 8It is a diagram for explaining the deformation of the trajectory of the smooth position.

[0024] Fig. 9 It is a diagram for explaining elimination of deformation of the trajectory of the smooth position. DETAILED DESCRIPTION

[0025] The following describes the embodiments of the present disclosure and the attached Figure 1 Let me explain.

[0026] The moving object detection system 1 of this embodiment is mounted on a vehicle, such as Figure 1 As shown, a radar device 2, an alarm device 3, a moving object detection device 4, and a steering angle sensor 5 are provided.

[0027] like Figure 2 As shown, the radar device 2 is installed at the right rear of the vehicle VH equipped with the moving object detection system 1. The radar device 2 transmits radar waves toward the right rear of the vehicle VH to detect moving objects (such as cars and two-wheeled vehicles) in the object detection area Rrr.

[0028] The radar device 2 is installed so that the central axis CA of the detection range of the receiving antenna is inclined rearwardly with respect to the width direction Dw of the vehicle VH at an installation angle of In addition, the detection range is set to include a range of, for example, ±80° centered on the central axis CA.

[0029] The radar device 2 adopts the well-known FMCW method to alternately transmit radar waves in the uplink modulation interval and radar waves in the downlink modulation interval at a preset modulation period, and receive the reflected radar waves. FMCW is the abbreviation of Frequency Modulated Continuous Wave. Thus, the radar device 2 detects the distance from the location (hereinafter, the observation point) where the radar wave is reflected, the relative speed to the observation point, the horizontal azimuth angle of the observation point, and the received power of the received radar wave in each modulation period. In addition, the horizontal azimuth angle is an angle relative to the central axis CA.

[0030] In addition, the radar device 2 outputs observation point information indicating the distance, relative speed, horizontal azimuth, and received power of the detected observation point to the moving object detection device 4 .

[0031] The alarm device 3 is a voice output device installed in the vehicle cabin, and outputs a warning sound to the occupants of the vehicle.

[0032] like Figure 1As shown, the moving object detection device 4 is an electronic control device composed of a well-known microcomputer having a CPU 11, a ROM 12, and a RAM 13. The various functions of the microcomputer are realized by the CPU 11 executing a program stored in a non-transitional physical recording medium. In this example, the ROM 12 is equivalent to a non-transitional physical recording medium storing the program. In addition, by executing the program, a method corresponding to the program is executed. In addition, a part or all of the functions performed by the CPU 11 may also be constituted by hardware such as one or more ICs. In addition, the number of microcomputers constituting the moving object detection device 4 may be one or more.

[0033] The steering angle sensor 5 detects the rotation angle of the steering wheel in the vehicle VH, and outputs a steering angle signal indicating the detection result to the moving object detection device 4 .

[0034] Next, the procedure of the rear approach warning process executed by the CPU 11 of the moving object detection device 4 will be described. The rear approach warning process is a process that is repeatedly executed every time the above-mentioned modulation cycle passes during the operation of the moving object detection device 4.

[0035] If the rear approach warning is executed, Figure 3 As shown, the CPU 11 first acquires observation point information from the radar device 2 in S10. Then, in S20, the CPU 11 determines whether there is a predicted point calculated in the previous rear approach warning process. The predicted point is calculated in S190 described later.

[0036] Here, if there is no predicted point, the CPU 11 moves to S180. On the other hand, if there is a predicted point, the CPU 11 sets the tracking area in S30. Specifically, Figure 5 As shown, the CPU 11 sets a rectangular area as the following area R1, the rectangular area having the predicted point position Xp(k+1) calculated in S190 described later in the rear approach warning process executed one modulation cycle ago as the center, the length along the front-to-rear direction of the vehicle VH being a predetermined longitudinal length L1, and the length along the width direction Dw of the vehicle VH being a predetermined lateral length L2. In the present embodiment, the longitudinal length L1 is, for example, 6 m, and the lateral length L2 is 4 m.

[0037] Then, if the processing of S30 is finished, Figure 3As shown, the CPU 11 determines in S40 whether the position of the observation point specified by the distance and horizontal azimuth indicated by the observation point information obtained in S10 (hereinafter, the current observation point position) is included in the following area set in S30. Here, in the case where the current observation point position is within the following area, the CPU 11 determines in S50 whether the received power indicated by the observation point information obtained in S10 (hereinafter, the acquired received power) is greater than the maximum received power Pmax set in RAM 13. Here, in the case where the acquired received power is less than the maximum received power Pmax, the CPU 11 moves to S70. On the other hand, in the case where the acquired received power is greater than the maximum received power Pmax, the CPU 11 stores the value of the acquired received power in the maximum received power Pmax in S60, thereby updating the maximum received power Pmax, and moves to S70.

[0038] Figure 6 : is a graph showing an example of the correspondence between the distance from the radar device 2 to the moving object and the received power. Figure 6 The dotted line Lmax in FIG. 1 represents the peak holding value of the received power, that is, the maximum received power Pmax. In addition, the area surrounded by rectangular frames FL1 and FL2 represents a portion where the SN ratio is reduced due to multipath.

[0039] Moreover, if Figure 3 As shown, if the process moves to S70, the CPU 11 determines whether the vehicle VH is traveling straight or traveling on a gentle curve based on the steering angle signal from the steering angle sensor 5. Specifically, the CPU 11 first calculates the radius of curvature R of the road on which the vehicle VH is traveling based on the steering angle indicated by the steering angle signal. Then, when the absolute value of the calculated radius of curvature R is less than a preset straight-travel determination value (for example, 500 m in this embodiment), the CPU 11 determines that the vehicle VH is traveling straight or traveling on a gentle turning lane. Here, when the vehicle VH is traveling straight or traveling on a gentle turning lane, the CPU 11 determines in S80 whether the subtraction value obtained by subtracting the received power from the maximum received power Pmax (hereinafter, the received power difference) is greater than a preset reduction determination value. In addition, the reduction determination value is set with reference to the reduction determination value map. The reduction determination value map is set to have a negative correlation between the distance represented by the observation point information obtained by S10 and the reduction determination value. Here, "having a negative correlation with the distance" means that the reduction determination value not only decreases in stages as the distance increases, but also includes the situation where the reduction determination value decreases continuously as the distance increases.

[0040] Here, when the received power difference is greater than the reduction determination value, the CPU 11 determines in S90 whether the received power is below the preset recognition determination value. In addition, the recognition determination value is set with reference to the recognition determination value map. The recognition determination value map is set to have a negative correlation between the distance represented by the observation point information obtained by S10 and the recognition determination value. In addition, "having a negative correlation with the distance" means that it includes not only the situation that the recognition determination value decreases in stages as the distance increases, but also the situation that the recognition determination value decreases continuously as the distance increases.

[0041] Here, when the received power is below the identification determination value, the CPU 11 sets the following filter coefficients α and β described later in S100 and moves to S180. Specifically, the CPU 11 calculates the following filter coefficient α with reference to the first reduction time map. Furthermore, the CPU 11 calculates the following filter coefficient β with reference to the second reduction time map.

[0042] The first reduction time mapping and the second reduction time mapping are respectively set to have a positive correlation between the distance represented by the observation point information obtained by S10 and the tracking filter coefficient α and the tracking filter coefficient β. Here, "having a positive correlation with the distance" means not only including the situation that the tracking filter coefficient increases in stages as the distance increases, but also including the situation that the tracking filter coefficient increases continuously as the distance increases.

[0043] On the other hand, when the acquired received power is larger than the identification determination value, the CPU 11 proceeds to S110. Also, when the received power difference is equal to or smaller than the decrease determination value in S80, the CPU 11 proceeds to S110.

[0044] Then, when the process moves to S110, the CPU 11 sets the following filter coefficients α and β described later, and moves to S180. Specifically, the CPU 11 calculates the following filter coefficient α by referring to the first normal time map. Furthermore, the CPU 11 calculates the following filter coefficient β by referring to the second normal time map.

[0045] The first normal time mapping and the second normal time mapping are respectively set to have a positive correlation between the distance represented by the observation point information obtained by S10 and the tracking filter coefficient α and the tracking filter coefficient β. In addition, the first normal time mapping is set so that when the distance is equal, the tracking filter coefficient α is larger than the first reduced time mapping. Similarly, the second normal time mapping is set so that when the distance is equal, the tracking filter coefficient β is larger than the second reduced time mapping.

[0046] like Figure 7As shown, when the RCS of the mobile object detected by the radar device 2 is large, even when the received power difference is larger than the reduction determination value, the received power is larger than the recognition determination value. Therefore, the setting of the tracking filter coefficients α and β in S110 is performed. RCS is the abbreviation of Radar Cross Section. On the other hand, when the RCS of the mobile object detected by the radar device 2 is small, when the received power difference is larger than the reduction determination value, the received power is smaller than the recognition determination value. Therefore, the setting of the tracking filter coefficients α and β in S100 is performed.

[0047] In addition, if Figure 3 As shown, in S70, when the vehicle VH is not traveling straight and the vehicle VH is not traveling on a gentle turning lane, the CPU 11 sets the following filter coefficients α and β described later in S120 and moves to S180. Specifically, the CPU 11 calculates the following filter coefficient α by referring to the first curve map. Furthermore, the CPU 11 calculates the following filter coefficient β by referring to the second curve map.

[0048] The first curve map and the second curve map are respectively set to have a positive correlation between the distance represented by the observation point information obtained by S10 and the tracking filter coefficient α and the tracking filter coefficient β. In addition, the first curve map is set so that the tracking filter coefficient α is larger than the first normal map when the distance is equal. Similarly, the second curve map is set so that the tracking filter coefficient β is larger than the second normal map when the distance is equal.

[0049] Then, if we move to S180, Figure 4 As shown, CPU11 performs smoothing processing. In the present embodiment, CPU11 performs the well-known α-β filter processing as smoothing processing. Specifically, CPU11 uses the following equations (1) and (2) to calculate the smoothed position Xs(k) and the smoothed speed Vs(k). The detection timing indication value k is an integer greater than 0 representing the detection timing of multiple observation points corresponding to the same object detected by the radar device 2. That is, the detection timing indication value k of the earliest detected observation point among the multiple observation points corresponding to the same object is 0, and the observation point with the earlier detection timing is assigned a smaller detection timing indication value k. Hereinafter, Xs(k) is referred to as the kth smoothed position, and Vs(k) is referred to as the kth smoothed speed.

[0050] Xs(k)=Xp(k)+α{Xm(k)-Xp(k)}···(1)

[0051] Vs(k)=Vs(k-1)+(β / T){Xm(k)-Xp(k)}···(2)

[0052] T in equation (2) is the modulation period. α in equation (1) and β in equation (2) are tracking filter coefficients. Xm(k) in equations (1) and (2) is the kth observation point position, which is calculated based on the distance and horizontal azimuth angle indicated by the observation point information acquired in S10.

[0053] Xp(k) in equations (1) and (2) is the k-th prediction point position, and is calculated by the following equation (3) in S210 described later in the rear approach warning process executed one modulation cycle ago.

[0054] Next, in S190 , the CPU 11 calculates the predicted point position Xp(k+1) using the following equation (3).

[0055] Xp(k+1)=Xs(k)+T×Vs(k)···(3)

[0056] Furthermore, in S200 , the CPU 11 resets the extrapolation counter provided in the RAM 13 (ie, sets it to 0), and the process proceeds to S210 .

[0057] In addition, in S40, when the position of the observation point is not included in the tracking area, the CPU 11 determines in S130 whether the value of the extrapolation counter (hereinafter, the number of extrapolation times) is greater than a preset extrapolation stop determination value (in this embodiment, for example, 5). Here, when the number of extrapolation times is greater than the extrapolation stop determination value, the CPU 11 initializes the maximum received power Pmax (for example, sets it to 0 [dB]) in S170, and temporarily terminates the rear approach warning process.

[0058] On the other hand, when the number of extrapolation times is less than the extrapolation stop determination value, CPU 11 performs extrapolation processing in S140. Specifically, CPU 11 updates the position calculated previously when moving at the latest smooth speed during one modulation cycle with the latest smooth position as the starting point as the latest smooth position.

[0059] Then, in S150, the CPU 11 sets the position moved during one modulation cycle at the latest smoothing speed starting from the latest smoothing position updated in S140 as the latest prediction point position. Then, in S160, the CPU 11 increments the interpolation counter by one and moves to S210.

[0060] Then, if the process moves to S210, the CPU 11 determines whether a preset alarm condition is satisfied. The alarm condition of the present embodiment is that the following first condition, second condition, and third condition are all satisfied. The first condition is that the smooth position is behind the vehicle VH. The second condition is that the smooth position is included in the lane adjacent to the right side of the lane in which the vehicle VH is traveling. The third condition is that the collision prediction time TTC calculated from the distance between the vehicle VH and the smooth position and the smooth speed is less than a preset alarm determination time (in the present embodiment, for example, 2 seconds). TTC is the abbreviation of Time To Collision.

[0061] Here, when the alarm condition is not satisfied, the CPU 11 terminates the output of the warning sound based on the alarm device 3 in S220, and temporarily terminates the rear approach warning process. Thus, when the alarm device 3 outputs the warning sound, the output of the warning sound is interrupted, and when the alarm device 3 does not output the warning sound, the state of not outputting the warning sound continues.

[0062] On the other hand, when the alarm condition is established, CPU11 causes the alarm device 3 to output a warning sound in S230, temporarily ending the rear approach warning process. Thus, when the alarm device 3 outputs a warning sound, the state of outputting the warning sound continues, and when the alarm device 3 does not output a warning sound, the output of the warning sound begins.

[0063] The moving object detection device 4 configured in this way repeatedly acquires observation point information from the radar device 2 mounted on the vehicle VH and transmitting and receiving radar waves. The observation point information indicates at least the observation point position, which is the position of the observation point reflecting the radar wave, and the received power, which is the power of the received radar wave.

[0064] The moving object detection device 4 estimates a tracking trajectory of the moving object corresponding to the plurality of observation points based on the observation point positions indicated by the plurality of observation point information acquired at different times.

[0065] The moving object detection device 4 stores the maximum received power Pmax which is the maximum value of the received power based on the received powers indicated by the plurality of observation point information acquired at different times.

[0066] The moving object detection device 4 determines whether a received power difference, which is a subtraction value obtained by subtracting the received power indicated by the acquired observation point information from the stored maximum received power Pmax, is larger than a preset decrease determination value.

[0067] The moving object detection device 4 determines whether the reception power indicated by the acquired observation point information is equal to or less than a preset recognition determination value.

[0068] When determining that the received power difference is larger than the decrease determination value and that the received power is equal to or less than the identification determination value, the moving object detection device 4 suppresses the degree of following the observation point in the estimated following trajectory.

[0069] In this way, the mobile object detection device 4 determines that the SN ratio is reduced when it is determined that the received power difference ratio is greater than the reduction determination value and the received power is less than the identification determination value. Moreover, when the mobile object detection device 4 determines that the SN ratio is reduced, it suppresses the degree of following the observation point in the estimated following trajectory. When the SN ratio is reduced, the position detection accuracy of the observation point detected is low, so the mobile object detection device 4 suppresses the influence of the observation point with low position detection accuracy, can estimate the following trajectory of the mobile object, and can improve the position detection accuracy of the mobile object.

[0070] In addition, the moving object detection device 4 estimates the following trajectory based on the observation point positions indicated by the plurality of observation point information and the following filter coefficients α and β indicating the degree of following the observation point positions. Furthermore, the moving object detection device 4 sets the following filter coefficients α and β in such a way that the degree of following becomes smaller, thereby suppressing the degree of following in the following trajectory. Thus, the moving object detection device 4 can suppress the degree of following in the following trajectory by a simple method of setting the following filter coefficients α and β.

[0071] Figure 8 10 shows the distribution of observation point positions and smoothed positions when a moving object TG approaching the vehicle VH from the right rear side is detected using a moving object detection device that does not adopt the method of setting the tracking filter coefficient of the present disclosure. Figure 8 The point group G1 is a trajectory of smooth positions (ie, a following trajectory). The mobile object TG is traveling in a lane further to the right of the adjacent lane adjacent to the right side of the vehicle VH.

[0072] like Figure 8 As shown in FIG. 1 , in the area surrounded by the circle CL, the SN ratio is reduced due to multipath such as the road surface, and the azimuth detection accuracy based on the radar device 2 is reduced, so that the smooth position of the moving object TG is arranged in the adjacent lane. That is, the moving object detection device 4 determines that the moving object TG has changed lanes to the adjacent lane regardless of whether the moving object TG is moving straight.

[0073] Fig. 9 1 shows the distribution of observation point positions and smoothed positions when a moving object TG approaching the vehicle VH from the right rear of the vehicle VH is detected using the moving object detection device 4 of the present disclosure. Fig. 9 The point group G2 is a trajectory of smooth positions (ie, a following trajectory). The mobile object TG is traveling in a lane further to the right of the adjacent lane adjacent to the right side of the vehicle VH.

[0074] like Fig. 9 As shown in FIG. 1 , the smooth position of the moving object TG is not arranged in the adjacent lane. Therefore, the moving object detection device 4 determines that the moving object TG is traveling in a lane further to the right of the adjacent lane adjacent to the right side of the vehicle VH.

[0075] In addition, the moving object detection device 4 sets the recognition determination value in such a manner that there is a negative correlation between the distance from the moving object to the vehicle VH and the recognition determination value. Furthermore, the moving object detection device 4 sets the reduction determination value in such a manner that there is a negative correlation between the distance from the moving object to the vehicle VH and the reduction determination value. Thus, the moving object detection device 4 can set the recognition determination value and the reduction determination value to appropriate values ​​corresponding to the reduction in received power caused by the increase in the distance from the moving object to the vehicle VH.

[0076] In addition, the moving object detection device 4 determines whether a preset suppression execution condition indicating whether the vehicle is traveling in a straight line or in a gentle turning lane is satisfied. In the present embodiment, the suppression execution condition is that the steering angle is within a preset straight line judgment range. Moreover, when the moving object detection device 4 determines that the suppression execution condition is not satisfied, it prohibits the suppression of the degree of following in the following trajectory. Thus, when the vehicle produces a sharp position change in the width direction Dw of the vehicle VH in the position detection result of the moving object based on the radar device 2 due to traveling in an uneven turning lane, the moving object detection device 4 can suppress the degradation of the responsiveness of the moving object in the following trajectory of the moving object to the actual position of the moving object.

[0077] In addition, the moving object detection device 4 sets the following filter coefficients α and β so that the following degree is greater when it is determined that the suppression execution condition is not satisfied than when it is determined that the suppression execution condition is satisfied, thereby promoting the following degree of the observation point in the estimated following trajectory. As a result, when the vehicle travels on an uneven turning lane and a sudden position change occurs in the width direction Dw of the vehicle VH in the position detection result of the moving object by the radar device 2, the moving object detection device 4 can improve the responsiveness of the moving object in the following trajectory of the moving object to the actual position of the moving object.

[0078] In the above-described embodiment, S10 corresponds to the process as the information acquisition unit, S180 corresponds to the process as the trajectory estimation unit, and S50 and S60 correspond to the process as the maximum power storage unit.

[0079] In addition, S80 corresponds to the processing as the power reduction determination unit, S90 corresponds to the processing as the identification determination unit, and S100 corresponds to the processing as the suppression unit.

[0080] In addition, S70 corresponds to the processing as the suppression determination unit and the prohibition unit, and S120 corresponds to the processing as the promotion unit.

[0081] As mentioned above, although one embodiment of the present disclosure has been described, the present disclosure is not limited to the above embodiment, and can be implemented with various modifications.

[0082] [Modification 1]

[0083] For example, in the above embodiment, the radar device 2 adopts the FMCW method, but the radar method of the radar device 2 is not limited to FMCW, and for example, dual-frequency CW or FCM may be adopted. FCM is the abbreviation of Fast-Chirp Modulation.

[0084] [Modification 2]

[0085] In the above embodiment, the radar device 2 transmits radar waves toward the right rear of the vehicle VH, but the transmission direction of the radar waves is not limited to the right rear of the vehicle VH. For example, the radar device 2 may transmit radar waves toward at least one of the front, right front, left front, rear, right rear, left rear, right side, and left side of the vehicle VH.

[0086] [Variation 3]

[0087] In the above embodiment, when the steering angle is within the preset straight-moving determination range, it is determined that the vehicle VH is moving straight or that the vehicle VH is traveling on a gentle lane change. However, the determination of moving straight or traveling on a gentle lane change is not limited to the above, and for example, the determination may be made using the yaw rate of the vehicle VH and the driving speed of the vehicle VH.

[0088] In addition, multiple components may share the function of one component in the above-mentioned embodiment, or one component may perform the functions of multiple components. In addition, a part of the structure of the above-mentioned embodiment may be omitted. In addition, at least a part of the structure of the above-mentioned embodiment may be added to or replaced with the structure of other above-mentioned embodiments.

[0089] In addition to the above-mentioned moving object detection device 4, the present disclosure can also be implemented in various forms such as a system with the moving object detection device 4 as a constituent element, a program for causing a computer to function as the moving object detection device 4, a medium recording the program, a moving object detection method, etc.

Claims

1. A moving object detection device, wherein: The moving object detection device comprises: an information acquisition unit configured to repeatedly acquire observation point information from a radar device mounted on the vehicle and transmitting and receiving radar waves, the observation point information indicating at least the observation point position, which is the position of the observation point reflecting the radar wave, and the received power, which is the power of the radar wave received; a trajectory estimating unit configured to estimate a tracking trajectory of a mobile object that follows the movement of the plurality of observation points based on the observation point positions indicated by the plurality of observation point information, wherein the plurality of observation point information is acquired by the information acquiring unit at different times; a maximum power storage unit configured to store a maximum value of the received power, that is, a maximum received power, based on the received power indicated by the plurality of observation point information, wherein the plurality of observation point information is acquired by the information acquisition unit at mutually different times; a power reduction determination unit configured to determine whether a received power difference is greater than a preset reduction determination value, wherein the received power difference is a subtraction value obtained by subtracting the received power represented by the observation point information acquired by the information acquisition unit from the maximum received power stored in the maximum power storage unit; an identification determination unit configured to determine whether the received power indicated by the observation point information acquired by the information acquisition unit is equal to or less than a preset identification determination value; and The suppression unit is configured to suppress the degree of following the observation point in the following trajectory estimated by the trajectory estimating unit, based on the radar cross-sectional area of ​​the moving object detected by the radar device, by judging that the SN ratio is reduced when the power reduction judgment unit judges that the received power difference is larger than the reduction judgment value and the recognition judgment unit judges that the received power is less than the recognition judgment value.

2. The moving object detection device according to claim 1, wherein: The trajectory estimating unit estimates the following trajectory based on the observation point positions indicated by the plurality of observation point information and a following filter coefficient indicating the degree of following the observation point positions. The suppression unit suppresses the degree of following in the following trajectory by setting the following filter coefficient so that the degree of following becomes smaller.

3. The moving object detection device according to claim 1, wherein: The recognition determination unit sets the recognition determination value so that there is a negative correlation between the distance from the moving object to the vehicle and the recognition determination value.

4. The moving object detection device according to claim 2, wherein: The recognition determination unit sets the recognition determination value so that there is a negative correlation between the distance from the moving object to the vehicle and the recognition determination value.

5. The moving object detection device according to any one of claims 1 to 4, wherein: The power reduction determination unit sets the reduction determination value so that there is a negative correlation between the distance from the moving object to the vehicle and the reduction determination value.

6. The moving object detection device according to any one of claims 1 to 4, wherein: have: a suppression determination unit configured to determine whether a preset suppression execution condition indicating whether the vehicle is traveling straight or traveling in a gentle lane change is satisfied; and The prohibition unit is configured to prohibit the suppression unit from suppressing the following degree when the suppression determination unit determines that the suppression execution condition is not satisfied.

7. The moving object detection device according to claim 5, wherein: have: a suppression determination unit configured to determine whether a preset suppression execution condition indicating whether the vehicle is traveling straight or making a gentle lane change is satisfied; and The prohibition unit is configured to prohibit the suppression unit from suppressing the following degree when the suppression determination unit determines that the suppression execution condition is not satisfied.

8. The moving object detection device according to claim 6, wherein: A promotion unit is provided, the promotion unit being configured to promote the degree of following the observation point in the following trajectory estimated by the trajectory estimating unit when the suppression determining unit determines that the suppression execution condition is not satisfied.

9. The moving object detection device according to claim 7, wherein: A promotion unit is provided, the promotion unit being configured to promote the degree of following the observation point in the following trajectory estimated by the trajectory estimating unit when the suppression determining unit determines that the suppression execution condition is not satisfied.

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