Vehicle control device and control method

Abstract

Provided are a control device and a control method for a vehicle capable of correcting the vehicle speed with high precision on the basis of the relative speed of a stationary object detected by a radar device or a LiDAR. A control device (10) for a vehicle (1) is provided with a radar device (33) or LiDAR capable of detecting a plurality of external objects (100), and is provided with: a vehicle speed acquisition unit (11) that acquires a vehicle speed detected by a vehicle speed sensor (21) mounted on the vehicle (1); and a vehicle speed correction unit (13) that corrects the vehicle speed on the basis of the detection results of the radar device (33) or the LiDAR. When the number of stationary objects (110) is equal to or greater than a predetermined number, the vehicle speed correction unit (13) corrects the vehicle speed on the basis of the relative speeds of the plurality of stationary objects (110) with respect to the vehicle (1) detected by the radar device (33) or the LiDAR.

Description

Technical Field

[0001] The present invention relates to a control device and a control method for a vehicle equipped with a radar device or LiDAR capable of detecting a plurality of external objects. Background Art

[0002] In recent years, efforts to provide sustainable transportation systems that take into account vulnerable individuals, particularly those in traffic, have intensified. To achieve this, research and development efforts are underway in driving support and preventive safety technologies to further improve traffic safety and convenience. In these technologies, there is a strong demand for highly accurate vehicle speed calculations to ensure accurate vehicle control.

[0003] For example, Patent Document 1 describes a radar device that corrects the vehicle speed detected based on wheel rotation based on the relative speed of stationary objects surrounding the vehicle.

[0004]

Prior technical literature

[0005] [Patent Literature]

[0006] [Patent Document 1] Japanese Patent No. 6832166 Summary of the Invention

[0007] [Problems to be solved by the invention]

[0008] In technologies such as Patent Document 1 that correct the detected vehicle speed based on the relative speed of a stationary object, the objects estimated as stationary may include objects temporarily moving at low speeds. Even in such situations, there is room for improvement in accurately calculating the vehicle speed without compromising the accuracy of the speed correction.

[0009] The present invention provides a vehicle control device and a control method capable of accurately correcting the vehicle speed based on the relative speed of a stationary object detected by a radar device or a LiDAR.

[0010]

Solutions to Solve the Problem

[0011] The present invention relates to a control device for a vehicle including a radar device or a LiDAR device capable of detecting a plurality of external objects.

[0012] The vehicle control device comprises:

[0013] a vehicle speed acquisition unit that acquires a vehicle speed detected by a vehicle speed sensor mounted on the vehicle; and

[0014] a vehicle speed correction unit that corrects the vehicle speed based on a detection result of the radar device or the LiDAR,

[0015] The vehicle speed correction unit acquires information on a plurality of stationary objects estimated to be stationary from among the plurality of objects based on the detection result of the radar device or the LiDAR.

[0016] The vehicle speed correction unit corrects the vehicle speed based on relative speeds of the plurality of stationary objects with respect to the vehicle detected by the radar device or the LiDAR when a predetermined condition is satisfied.

[0017] The predetermined condition includes that the number of the stationary objects is greater than or equal to a predetermined number.

[0018] The present invention also relates to a method for controlling a vehicle including a radar device or LiDAR capable of detecting a plurality of external objects, wherein:

[0019] The vehicle control method causes a computer to execute:

[0020] a vehicle speed obtaining step of obtaining a vehicle speed detected by a vehicle speed sensor mounted on the vehicle;

[0021] a stationary object information acquisition step of acquiring information of a plurality of stationary objects estimated to be stationary from among the plurality of objects based on a detection result of the radar device or the LiDAR;

[0022] a condition determination step of determining whether a predetermined condition is satisfied, including determining whether the estimated number of stationary objects is greater than a predetermined number; and

[0023] and a vehicle speed correction step of correcting the vehicle speed based on relative speeds of the plurality of stationary objects with respect to the vehicle detected by the radar device or the LiDAR when the predetermined condition is satisfied.

[0024] Effects of the invention

[0025] According to the present invention, it is possible to accurately correct the vehicle speed based on the relative speed of a stationary object detected by a radar device or a LiDAR. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a block diagram of a vehicle 1 including a control device 10 according to an embodiment of the present invention.

[0027] Figure 2 This diagram conceptually illustrates an example of a situation in which the radar device 33 detects a plurality of objects 100 in front of the vehicle 1 .

[0028] Figure 3This is another example conceptually showing a situation in which the radar device 33 detects a plurality of objects 100 (including moving objects) in front of the vehicle 1 .

[0029] Figure 4 Graph for explaining the variance of the relative speeds of a plurality of stationary objects 110 .

[0030] Figure 5 This is a flowchart showing an example of a process for correcting the detected vehicle speed.

[0031] Figure 6 This is a flowchart showing an example of the correction condition determination process.

[0032] Description of reference numerals:

[0033] 1 vehicle

[0034] 10 Control device

[0035] 11 Vehicle speed acquisition unit

[0036] 13. Vehicle speed correction unit

[0037] 21 Vehicle speed sensor

[0038] 33 Radar device

[0039] 100 object targets

[0040] 110 Still objects. DETAILED DESCRIPTION

[0041] Hereinafter, one embodiment of a vehicle control device and a vehicle control method according to the present invention will be described with reference to the accompanying drawings.

[0042] A vehicle 1 according to one embodiment of the present invention is an automobile having a drive source and wheels, the wheels including drive wheels driven by power from the drive source and steerable wheels. For example, the vehicle 1 can be a four-wheeled automobile having a pair of left and right front wheels and rear wheels.

[0043] The driving source of vehicle 1 may be an electric motor, an internal combustion engine such as a gasoline engine or a diesel engine, or a combination of an electric motor and an internal combustion engine. Furthermore, the driving source of vehicle 1 may drive a pair of left and right front wheels, a pair of left and right rear wheels, or four wheels: a pair of left and right front wheels and a pair of rear wheels. The front and rear wheels of vehicle 1 may be either steerable or both steerable.

[0044] like Figure 1As shown, vehicle 1 includes a control device 10, vehicle sensors 20 for acquiring information related to vehicle 1, and external sensors 30 for acquiring information related to the surroundings of vehicle 1. Detection values ​​detected by vehicle sensors 20 and external sensors 30 are output to control device 10 and used by control device 10 to control vehicle 1.

[0045] The vehicle sensor 20 includes, for example, a vehicle speed sensor 21 and an inertial measurement unit (IMU) 22 .

[0046] The vehicle speed sensor 21 detects the vehicle speed, which is the running speed of the vehicle 1. For example, the vehicle speed sensor 21 detects the vehicle speed based on the rotation of the wheels. Note that the vehicle speed sensor 21 may also detect the vehicle speed based on the rotation of an intermediate shaft or the like included in the vehicle 1.

[0047] The inertial measurement device 22 detects angular velocities in the pitch, roll, and yaw directions of the vehicle 1, as well as accelerations in the front-back, left-right, and up-down directions of the vehicle 1. It should be noted that the vehicle sensor 20 may include an acceleration sensor that detects acceleration in a predetermined direction of the vehicle 1, or a gyroscopic sensor that detects angular velocity in a predetermined direction of the vehicle 1, in place of the inertial measurement device 22.

[0048] The external sensor 30 includes, for example, a camera 31 , a sonar 32 , and a radar device 33 .

[0049] The camera 31 captures the surroundings of the vehicle 1 including the front of the vehicle 1 and outputs the obtained surrounding image data to the control device 10. The camera 31 can be a digital camera using an imaging element such as a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor).

[0050] The sonar 32 emits sound waves around the vehicle 1 (eg, in front of, behind, and to the sides of the vehicle 1 ) and receives reflected sound from objects around the vehicle 1 , thereby detecting the distance, direction, etc. to the objects.

[0051] The radar device 33 includes a transmitting unit 33a and a receiving unit 33b, each including an antenna. It transmits radio waves toward the periphery of the vehicle 1, including the front of the vehicle 1, and receives reflected waves from objects surrounding the vehicle 1. This allows the radar device 33 to detect the distance and direction to the object, or the relative speed of the object relative to the vehicle 1 based on the frequency of the reflected waves. For example, a millimeter-wave radar device can be employed as the radar device 33.

[0052] The radar device 33 includes a signal processing unit 33c that processes received signals. The signal processing unit 33c includes, for example, a processor that performs various calculations, a storage device that stores various information, and an input / output unit that controls input and output of data.

[0053] The signal processing unit 33c of the radar device 33 identifies an object estimated to be stationary (hereinafter referred to as a "stationary object") from among the multiple detected objects based on the relative speed of the objects. Examples of stationary objects detected by the radar device 33 include parked vehicles, roadside utility poles, and signs. The signal processing unit 33c calculates the absolute speed of the detected object based on the relative speed of the detected object and the vehicle speed detected by the vehicle speed sensor 21 (hereinafter referred to as the detected vehicle speed). If the absolute speed of the object is less than a predetermined speed, the signal processing unit 33c estimates the object as stationary and sets the stationary object flag for the object to active. If the absolute speed of the object is greater than the predetermined speed, the signal processing unit 33c estimates the object as moving and sets the stationary object flag for the object to inactive.

[0054] It should be noted that the external sensor 30 may also include LiDAR (Light Detection and Ranging). LiDAR emits laser light toward the periphery of the vehicle 1, including the front of the vehicle 1, and receives reflected light from objects around the vehicle 1. This detects the distance to the object, its direction, and the object's relative speed relative to the vehicle 1. Furthermore, LiDAR identifies a stationary object estimated to be stationary from among multiple objects based on their relative speed.

[0055] The control device 10 includes, for example, a processor 10a that performs various calculations, a storage unit 10b having a non-transitory storage medium that stores various information, and an input / output unit 10c that controls the input and output of data within and outside the control device 10. It is a computer that comprehensively controls the entire vehicle 1. For example, the control device 10 may be implemented as a single ECU (Electronic Control Unit) or as a coordinated system of multiple ECUs.

[0056] The control device 10 includes, for example, a vehicle speed acquisition unit 11 , an acceleration acquisition unit 12 , and a vehicle speed correction unit 13 as functional units implemented by the processor 10 a executing a program stored in the storage unit 10 b .

[0057] The vehicle speed acquisition unit 11 receives a signal from the vehicle speed sensor 21 and acquires the detected vehicle speed of the vehicle 1. The acceleration acquisition unit 12 receives a signal from the inertial measurement unit 22 and acquires the acceleration in each direction of the vehicle 1. It should be noted that the vehicle speed acquisition unit 11 may also be configured to acquire the vehicle speed of the vehicle 1 as the detected vehicle speed based on the signals from the vehicle speed sensor 21 and the signals from the inertial measurement unit 22.

[0058] The vehicle speed correction unit 13 corrects the detected vehicle speed obtained by the vehicle speed acquisition unit 11 when predetermined correction conditions, described later, are met. The detected vehicle speed may contain errors relative to the actual vehicle speed due to changes in wheel diameter due to changes in tire air pressure, wear, and the like. Therefore, correction by the vehicle speed correction unit 13 reduces the error between the detected and actual vehicle speeds.

[0059] The vehicle speed correction unit 13 calculates a correction value based on the detected vehicle speed and the relative speeds of multiple stationary objects detected by the radar device 33, and corrects the detected vehicle speed based on the correction value. The correction value is, for example, a correction ratio obtained by dividing the average of the relative speeds of the multiple stationary objects by the detected vehicle speed.

[0060] This correction allows the detected vehicle speed to be brought closer to the actual vehicle speed, thereby improving the accuracy and reliability of driving control related to driving support, including, for example, automated driving of vehicle 1 (autonomous driving of vehicle 1 independent of driver input). Driving support includes, for example, collision mitigation braking control (also known as CMBS (Collision Mitigation Brake System)) that assists vehicle 1 in avoiding and mitigating a collision with a forward object when the likelihood of a collision with the object is high.

[0061] Figure 2 This diagram conceptually illustrates an example of a situation in which radar device 33 detects multiple objects 100 in front of vehicle 1. In the illustrated example, radar device 33 is mounted on the center front portion of vehicle 1, but the present invention is not limited thereto and any mounting location on vehicle 1 is acceptable as long as it can transmit radio waves in the direction forward of vehicle 1.

[0062] Radar device 33 transmits radio waves in front of vehicle 1 and receives reflected waves from surrounding objects, thereby detecting multiple targets 100 in front of vehicle 1. Radar device 33 infers stationary targets as stationary objects 110 based on the relative speed of target 100 and the detected vehicle speed, and activates a stationary object flag for each stationary object 110.

[0063] exist Figure 2In the example shown, the radar device 33 detects the utility pole 100a, the parked vehicle 100b, the sign 100c, and the pole 100d in front of the vehicle 1 as object targets 100. Furthermore, the radar device 33 calculates the absolute speed of each object target 100 based on the relative speed of each object target 100 and the detected vehicle speed. The utility pole 100a, the parked vehicle 100b, the sign 100c, and the pole 100d are completely stationary object targets 100, and the calculated absolute speed of each object target 100 is less than the aforementioned specified speed, so the radar device 33 infers these object targets 100 as stationary objects 110. It should be noted that in Figure 2 In the figure, a situation where a utility pole 100a, a parked vehicle 100b, a signboard 100c and a pole 100d are present in front of the vehicle 1 as multiple object targets 100 is illustrated, but in reality, there are many objects including moving objects and other stationary objects not shown, and they are detected by the radar device 33.

[0064] The control device 10 obtains information about multiple objects 100 from the radar device 33. Specifically, the control device 10 obtains information such as the distance, direction, and relative speed between the vehicle 1 and each object 100, as well as information about the stationary object flag of each object 100, from the radar device 33. Thus, the control device 10 recognizes the presence of multiple objects 100 detected by the radar device 33 and the stationary object 110 included in the multiple objects 100.

[0065] The control device 10 corrects the detected vehicle speed based on the relative speed of the stationary object 110 and the detected vehicle speed. If the stationary object 110 is completely stationary, the relative speed of the stationary object 110 is close to the actual vehicle speed of the vehicle 1.

[0066] Figure 3 This is another example conceptually showing a situation where the radar device 33 detects a plurality of objects 100 in front of the vehicle 1. Figure 3 , a case where a plurality of pedestrians 120 (an example of the moving object 100 ) are present in front of the vehicle 1 is shown.

[0067] Radar device 33 and Figure 2 Similarly, in the case of the vehicle 1, the utility pole 100a, signboard 100c, and pole 100d in front of the vehicle 1 are estimated as stationary objects 110, and the stationary object flags of each are set to active. On the other hand, the radar device 33 estimates that a plurality of pedestrians 120 are moving objects, and the stationary object flags of the pedestrians 120 are set to inactive.

[0068] However, for example, if pedestrian 121 is walking at a slow speed among multiple pedestrians 120, radar device 33 may infer pedestrian 121 as stationary object 110 and activate the stationary object flag for pedestrian 121. In other words, the stationary object 110 inferred based on the detection results of radar device 33 may include not only completely stationary objects but also moving objects (here, pedestrian 121). As described above, the correction of the detected vehicle speed by control device 10 is based on the relative speed of stationary object 110. Therefore, even when a moving object is included in stationary object 110, the accuracy of the correction of the detected vehicle speed must not be reduced, and the vehicle speed must be calculated with high accuracy.

[0069] In this embodiment, the control device 10 corrects the vehicle speed when a predetermined correction condition is met. Specifically, the correction condition includes the estimated number of stationary objects 110 being greater than a predetermined number (e.g., greater than 10). When the estimated number of stationary objects 110 is greater than the predetermined number, the control device 10 corrects the detected vehicle speed based on the relative speeds of the plurality of stationary objects 110. In other words, when the estimated number of stationary objects 110 is less than the predetermined number, the control device 10 does not correct the detected vehicle speed.

[0070] With this configuration, even if the estimated multiple stationary objects 110 include a moving object (e.g., pedestrian 121), the presence of the other stationary objects 110, which are completely stationary, reduces the impact of the moving object. This prevents a decrease in the accuracy of the detected vehicle speed correction, enabling highly accurate vehicle speed correction. Furthermore, if the number of estimated stationary objects 110 is less than a specified number, the detected vehicle speed is not corrected, thus avoiding inaccurate corrections.

[0071] Furthermore, even when the estimated multiple stationary objects 110 do not include any moving objects, variations in the distance between each stationary object 110 and the vehicle 1 may cause deviations in the detected relative speed, reducing the accuracy of the corrected detected vehicle speed. The control device 10 of this embodiment corrects the detected vehicle speed when the number of estimated stationary objects 110 is greater than a predetermined number. This can suppress such a reduction in correction accuracy and enable highly accurate vehicle speed correction. Therefore, by increasing the accuracy of vehicle speed information used in driving support technology, the reliability of the driving support technology can be improved.

[0072] In order to improve the correction accuracy of the detected vehicle speed, the aforementioned correction conditions preferably include further conditions in addition to the estimated number of stationary objects 110 being equal to or greater than a predetermined number.

[0073] For example, it is preferable that the correction condition further includes that the variance of the relative speeds of the plurality of stationary objects 110 is smaller than a prescribed value.

[0074] Figure 4 This graph illustrates the variance in the relative velocities of multiple stationary objects 110 and shows the distribution of the relative velocities of each of the multiple stationary objects 110. Graph A (thick solid line) shows a narrow distribution of detected stationary objects 110, with the relative velocities of each stationary object 110 mostly concentrated around the average value. In other words, Graph A shows a graph with low variance in relative velocities. Graph A corresponds to a situation where the objects estimated as stationary objects 110 contain no moving objects, or even if they do, their number is small. On the other hand, Graph B (thin solid line) shows a wide distribution of detected stationary objects 110. In other words, Graph B shows a graph with high variance in relative velocities. Graph B corresponds to a situation where the objects estimated as stationary objects 110 contain more moving objects than Graph A.

[0075] When comparing the case where a detection result with a small variance such as that in Figure A is obtained by the radar device 33 with the case where a detection result with a large variance such as that in Figure B is obtained, it is considered that the proportion of moving object targets included in the object targets estimated to be stationary objects 110 in Figure A is low. Therefore, it is preferred that the control device 10 correct the vehicle speed when a detection result with a small variance such as that in Figure A is obtained. In addition, it is preferred that the control device 10 does not correct the vehicle speed when a detection result with a large variance such as that in Figure B is obtained. According to such a structure, the reduction in the correction accuracy of the vehicle speed can be more reliably suppressed. It should be noted that in the above-mentioned correction condition, instead of the variance of the relative speed, the standard deviation of the relative speed can be less than a specified value as a condition.

[0076] Preferably, the correction condition further includes that the number of estimated stationary objects 110 is greater than or equal to a predetermined number continues for a predetermined time or longer. The vehicle speed is corrected when the stationary objects 110 are stably detected, thereby improving the accuracy of vehicle speed correction.

[0077] Furthermore, the correction condition preferably further includes the fact that the estimated stationary object 110 is detected by the radar device 33 while the vehicle 1 is traveling straight ahead. The relative speed of the object 100 detected while the vehicle 1 is traveling straight ahead is detected with higher accuracy than the relative speed of the object 100 detected by the radar device 33 while the vehicle 1 is traveling along a curved road or making a left or right turn. When this correction condition is met, the detection accuracy of the relative speed of the stationary object 110 is increased, resulting in improved vehicle speed correction accuracy.

[0078] Furthermore, the correction condition preferably further includes the requirement that the estimated stationary object 110 be detected by the radar device 33 while the vehicle 1 is traveling at a first speed (e.g., 5 km / h) or higher. When the vehicle 1 is traveling at a low speed, the detection error of the relative speed of the object 100 may be relatively large. Therefore, the correction condition preferably includes a lower limit value for the traveling speed (i.e., the first speed). When this correction condition is met, the detection accuracy of the relative speed of the stationary object 110 is increased, resulting in improved accuracy in vehicle speed correction. It should be noted that the first speed can also be variably set based on the driving conditions of the vehicle 1 (such as the width of the road and the presence or absence of pedestrians).

[0079] Furthermore, the correction condition preferably further includes the condition that the estimated stationary object 110 is detected by the radar device 33 while the vehicle 1 is traveling at an acceleration below a predetermined acceleration. The acceleration here refers to, for example, the longitudinal acceleration and / or lateral acceleration of the vehicle 1, and a determination is made as to whether the longitudinal acceleration and / or lateral acceleration detected by the inertial measurement unit 22 is below the predetermined acceleration. The relative speed of the stationary object 110 detected by the radar device 33 is more accurately detected when the vehicle speed changes slightly than when the vehicle speed changes significantly. Therefore, when this correction condition is met, the detection accuracy of the relative speed of the stationary object 110 is increased, resulting in improved accuracy in vehicle speed correction.

[0080] Figure 5 1 is a flowchart showing an example of a process for correcting the detected vehicle speed by the control device 10. Figure 6 This is a flowchart showing an example of the process of determining the correction condition. The control device 10 executes the correction condition determination at a predetermined time interval. Figure 5 Flowchart of the process.

[0081] like Figure 5 As shown, the control device 10 first performs a correction condition determination (step S10). The correction condition determination is based on Figure 6 Flowchart to execute.

[0082] like Figure 6 As shown, during the correction condition determination, the control device 10 determines whether the various conditions included in the correction condition described above are met (steps S11 to S16). If all the various conditions included in the correction condition are met (steps S11 to S16: Yes), the control device 10 determines that the correction condition is met (step S17). On the other hand, if at least one of the various conditions included in the correction condition is not met (at least one of steps S11 to S16: No), the control device 10 determines that the correction condition is not met (step S18).

[0083] It should be noted that the order of steps S11 to S16 is not limited to this, and the order can be set arbitrarily. In addition, the correction condition determination does not need to include all steps of steps S11 to S16, and any steps can be omitted or other steps can be added.

[0084] return Figure 5 After executing the correction condition determination (step S10), the control device 10 determines whether the correction condition has been met (step S20). If the correction condition has been met (step S20: Yes), the control device 10 calculates and updates the correction value (step S21). Specifically, if the correction value calculated during the previous execution of the flowchart has already been set, the control device 10 updates the correction value calculated in step S21 to the new value. If the correction value has not been set (or is zero), the control device 10 sets the correction value in step S21.

[0085] If the correction condition is not met (step S20: No), the control device 10 maintains the correction value (step S22). Specifically, if the correction value calculated during the previous execution of the flowchart has already been set, the control device 10 maintains the correction value in step S22. If the correction value has not been set (or is zero), the control device 10 does not set the correction value in step S22.

[0086] Regarding step S21, it is preferred that the control device 10 imposes a limit on the correction value when the calculated correction value is outside the specified range. Specifically, when the correction rate, which is an example of a correction value, is outside the range of -5% to +5%, the corrected vehicle speed may deviate significantly from the detected vehicle speed, so the control device 10 imposes a limit on the correction rate. For example, when the correction rate exceeds +5%, the control device 10 sets the correction rate to +5%. In other words, +5% becomes the upper limit of the correction rate. When the correction rate is lower than -5%, the control device 10 sets the correction rate to -5%. In other words, -5% becomes the lower limit of the correction rate. According to such a structure, it is possible to prevent the corrected vehicle speed from being excessively set high or low.

[0087] Alternatively, the control device 10 may limit the corrected vehicle speed if the corrected vehicle speed is outside a predetermined range. Specifically, if the difference between the corrected vehicle speed and the detected vehicle speed is greater than a predetermined value, the corrected vehicle speed may significantly deviate from the detected vehicle speed, so the control device 10 limits the corrected vehicle speed. For example, if the difference between the corrected vehicle speed and the detected vehicle speed is greater than a predetermined value, the control device 10 sets the corrected vehicle speed to a predetermined upper or lower limit.

[0088] After step S21 or S22 , the control device 10 determines whether the detected vehicle speed is equal to or greater than a second speed (step S23 ). The second speed is approximately the same as the first speed or is slower than the first speed.

[0089] When the vehicle 1 is traveling at a low speed, the deviation between the detected vehicle speed and the actual vehicle speed is relatively small. Therefore, when the detected vehicle speed is less than the second speed, the control device 10 does not correct the detected vehicle speed regardless of whether the correction condition is met (step S25). This prevents excessive correction of the detected vehicle speed. As the speed of the vehicle 1 increases, the deviation between the detected vehicle speed and the actual vehicle speed increases. Therefore, when the detected vehicle speed is above the second speed, the control device 10 corrects the detected vehicle speed (step S24).

[0090] In this embodiment, while the ignition of vehicle 1 is switched from the on state to the off state, control device 10 maintains the correction value calculated in step S21 in storage unit 10b until the next correction condition is satisfied. This maintains the highly accurate correction value calculated in step S21 while the ignition is on, thereby improving the reliability of the driving support technology.

[0091] The control method described in the above embodiment can be implemented by executing a pre-prepared control program using a computer. This control program is stored in a storage medium that can be read by a computer, and is executed by being read from the storage medium. In addition, this control program can also be provided in the form of being stored in a non-temporary storage medium such as a flash memory, or can be provided via a network such as the Internet. The computer that executes this control program can be included in the control device 10, or it can be included in the radar device 33. In addition, the computer that executes this control program can be included in an electronic device such as a smartphone, tablet terminal or personal computer that can communicate with the control device 10 and / or the radar device 33, or it can be included in a server device that can communicate with them.

[0092] While one embodiment of the present invention has been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to the embodiment described. It is clear that those skilled in the art will be able to conceive of various variations or modifications within the scope of the technical solution, and it should be understood that such variations or modifications naturally fall within the technical scope of the present invention. Furthermore, the various components of the above-described embodiment may be arbitrarily combined without departing from the spirit of the invention.

[0093] For example, in the above embodiment, the detected vehicle speed is corrected based on the object 100 detected by the radar device 33, but the present invention is not limited thereto. The control device 10 may correct the detected vehicle speed based on the object detected by LiDAR.

[0094] Furthermore, in the aforementioned embodiment, the signal processing unit 33c of the radar device 33 is described as detecting the relative velocity of an object and estimating whether the object is a stationary object. However, the present invention is not limited to this. Alternatively, a configuration may be employed in which a function corresponding to the signal processing unit 33c is provided in the control device 10. In other words, the control device 10 may estimate whether an object detected by the radar device 33 is a stationary object based on the detection results of the radar device 33.

[0095] Furthermore, in the aforementioned embodiment, a limit is imposed on the correction value or the corrected vehicle speed in step S21. However, instead of this, a limit may be added to the aforementioned correction condition, which requires that the corrected vehicle speed be within a predetermined range relative to the detected vehicle speed, or that the correction value be within a predetermined range. With this configuration, the vehicle speed is not corrected if there is a possibility that the vehicle speed correction accuracy is low and the corrected vehicle speed is excessively high or low.

[0096] This specification describes at least the following matters: Corresponding components in the above-described embodiment are shown in parentheses as examples, but the present invention is not limited thereto.

[0097] (1) A control device (control device 10) of a vehicle (vehicle 1) including a radar device (radar device 33) or LiDAR capable of detecting a plurality of external objects (objects 100), wherein:

[0098] The vehicle control device comprises:

[0099] a vehicle speed acquisition unit (vehicle speed acquisition unit 11 ) that acquires the vehicle speed detected by a vehicle speed sensor (vehicle speed sensor 21 ) mounted on the vehicle; and

[0100] a vehicle speed correction unit (vehicle speed correction unit 13 ) that corrects the vehicle speed based on the detection result of the radar device or the LiDAR,

[0101] The vehicle speed correction unit acquires information on a plurality of stationary objects (stationary objects 110 ) estimated to be stationary from among the plurality of objects based on the detection result of the radar device or the LiDAR.

[0102] The vehicle speed correction unit corrects the vehicle speed based on relative speeds of the plurality of stationary objects with respect to the vehicle detected by the radar device or the LiDAR when a predetermined condition is satisfied.

[0103] The predetermined condition includes that the number of the stationary objects is greater than or equal to a predetermined number.

[0104] According to (1), when the number of estimated stationary objects is greater than or equal to a predetermined number, even when a temporarily moving object is estimated as a stationary object, the influence of the moving object is relatively small due to the presence of other completely stationary objects. This can suppress the reduction in the accuracy of vehicle speed correction, and enable high-precision vehicle speed correction. Therefore, by increasing the accuracy of vehicle speed information used in driving control by driving support technology, the reliability of driving support technology can be improved.

[0105] (2) In the vehicle control device described in (1),

[0106] The vehicle speed correction unit calculates a variance or a standard deviation of the relative speeds of the plurality of stationary objects.

[0107] The prescribed condition further includes that the variance or the standard deviation is smaller than a prescribed value.

[0108] According to (2), the vehicle speed is corrected when the proportion of moving objects among objects estimated as stationary is low. Furthermore, the vehicle speed is not corrected when the proportion of moving objects among objects estimated as stationary is high. This makes it possible to more reliably suppress a decrease in the accuracy of vehicle speed correction.

[0109] (3) In the control device for a vehicle described in (1) or (2),

[0110] The predetermined condition further includes that the state in which the number of the stationary objects is equal to or greater than the predetermined number continues for a predetermined time or longer.

[0111] According to (3), the vehicle speed is corrected when the stationary object is stably detected, so the correction accuracy of the vehicle speed is improved.

[0112] (4) In the control device for a vehicle according to any one of (1) to (3),

[0113] The prescribed condition further includes that the plurality of stationary objects are detected by the radar device or the LiDAR while the vehicle is traveling straight.

[0114] According to (4), the relative speed obtained from a stationary object detected while the vehicle is traveling straight ahead is more accurately detected than the relative speed obtained from a stationary object detected while the vehicle is traveling on a curve. Therefore, the accuracy of detecting the relative speed of the stationary object is improved, resulting in improved accuracy in correcting the vehicle speed.

[0115] (5) In the control device for a vehicle according to any one of (1) to (4),

[0116] The predetermined condition further includes that the plurality of stationary objects are detected by the radar device or the LiDAR while the vehicle is traveling at a speed greater than or equal to a first speed.

[0117] According to (5), when the vehicle travels at a speed greater than the first speed, the detection error of the relative speed of the stationary object becomes relatively small, and the detection accuracy of the stationary object becomes higher. As a result, the correction accuracy of the vehicle speed is improved.

[0118] (6) In the control device for a vehicle according to any one of (1) to (5),

[0119] The predetermined condition further includes that the plurality of stationary objects are detected by the radar device or the LiDAR while the vehicle is traveling at an acceleration equal to or less than a predetermined acceleration.

[0120] According to (6), the relative speed obtained from a stationary object detected when the change in vehicle speed is small has higher detection accuracy than the relative speed obtained from a stationary object detected when the change in vehicle speed is large, so the correction accuracy of the vehicle speed is improved.

[0121] (7) In the control device for a vehicle according to any one of (1) to (6),

[0122] The vehicle speed correction unit calculates a correction value based on the relative speed when the predetermined condition is satisfied.

[0123] The vehicle speed correction unit limits the correction value or the corrected vehicle speed when the calculated correction value is outside a predetermined range or when the corrected vehicle speed is outside a predetermined range relative to the vehicle speed acquired by the vehicle speed acquisition unit.

[0124] According to (7), when the corrected vehicle speed deviates significantly from the vehicle speed acquired by the vehicle speed acquisition unit, the correction value or the corrected vehicle speed is limited, thereby preventing the corrected vehicle speed from being excessively high or low.

[0125] (8) In the control device for a vehicle according to any one of (1) to (6),

[0126] The predetermined condition further includes that the corrected vehicle speed calculated by the vehicle speed correction unit is within a predetermined range relative to the vehicle speed acquired by the vehicle speed acquisition unit, or that the correction value calculated by the vehicle speed correction unit is within a predetermined range.

[0127] According to (8), it is possible to avoid correcting the vehicle speed when there is a possibility that the vehicle speed after correction is set excessively high or low due to low vehicle speed correction accuracy.

[0128] (9) In the vehicle control device described in any one of (1) to (8),

[0129] The vehicle speed correction unit calculates a correction value based on the relative speed when the predetermined condition is satisfied, and corrects the vehicle speed based on the correction value.

[0130] The vehicle speed correction unit maintains the correction value after the correction value is calculated and until the next predetermined condition is satisfied while the ignition of the vehicle is switched from the on state to the off state.

[0131] According to (9), a highly accurate correction value is maintained while the ignition is in the on state, thereby improving the reliability of the driving support technology.

[0132] (10) A method for controlling a vehicle (vehicle 1) including a radar device (radar device 33) or LiDAR capable of detecting a plurality of external objects (objects 100), wherein:

[0133] The vehicle control method causes a computer to execute:

[0134] a vehicle speed obtaining step of obtaining a vehicle speed detected by a vehicle speed sensor (vehicle speed sensor 21 ) mounted on the vehicle;

[0135] A stationary object information acquisition step of acquiring information of a plurality of stationary objects (stationary objects 110 ) estimated to be stationary from among the plurality of objects based on a detection result of the radar device or the LiDAR;

[0136] a condition determination step of determining whether a predetermined condition is satisfied, including determining whether the estimated number of stationary objects is greater than a predetermined number; and

[0137] and a vehicle speed correction step of correcting the vehicle speed based on relative speeds of the plurality of stationary objects with respect to the vehicle detected by the radar device or the LiDAR when the predetermined condition is satisfied.

[0138] According to (10), when the number of estimated stationary objects is greater than or equal to a predetermined number, even when a temporarily moving object is estimated as a stationary object, the influence of the moving object is relatively small due to the presence of other completely stationary objects. This can suppress the reduction in vehicle speed correction accuracy and enable high-precision vehicle speed correction. Therefore, by increasing the accuracy of vehicle speed information used in driving control by driving support technology, the reliability of driving support technology can be improved.

Claims

1. A control device for a vehicle, the vehicle comprising a radar device or a LiDAR device capable of detecting a plurality of external objects, wherein: The vehicle control device comprises: a vehicle speed acquisition unit that acquires a vehicle speed detected by a vehicle speed sensor mounted on the vehicle; and a vehicle speed correction unit that corrects the vehicle speed based on a detection result of the radar device or the LiDAR, The vehicle speed correction unit acquires information on a plurality of stationary objects estimated to be stationary from among the plurality of objects based on the detection result of the radar device or the LiDAR. The vehicle speed correction unit corrects the vehicle speed based on relative speeds of the plurality of stationary objects with respect to the vehicle detected by the radar device or the LiDAR when a predetermined condition is satisfied. The predetermined condition includes that the number of the stationary objects is greater than or equal to a predetermined number.

2. The vehicle control device according to claim 1, wherein: The vehicle speed correction unit calculates a variance or a standard deviation of the relative speeds of the plurality of stationary objects. The prescribed condition further includes that the variance or the standard deviation is smaller than a prescribed value.

3. The vehicle control device according to claim 1 or 2, wherein: The predetermined condition further includes that the state in which the number of the stationary objects is equal to or greater than the predetermined number continues for a predetermined time or longer.

4. The vehicle control device according to claim 1 or 2, wherein: The prescribed condition further includes that the plurality of stationary objects are detected by the radar device or the LiDAR while the vehicle is traveling straight.

5. The vehicle control device according to claim 1 or 2, wherein: The predetermined condition further includes that the plurality of stationary objects are detected by the radar device or the LiDAR while the vehicle is traveling at a speed greater than or equal to a first speed.

6. The vehicle control device according to claim 1 or 2, wherein: The predetermined condition further includes that the plurality of stationary objects are detected by the radar device or the LiDAR while the vehicle is traveling at an acceleration equal to or less than a predetermined acceleration.

7. The vehicle control device according to claim 1 or 2, wherein: The vehicle speed correction unit calculates a correction value based on the relative speed when the predetermined condition is satisfied. The vehicle speed correction unit limits the correction value or the corrected vehicle speed when the calculated correction value is outside a predetermined range or when the corrected vehicle speed is outside a predetermined range relative to the vehicle speed acquired by the vehicle speed acquisition unit.

8. The vehicle control device according to claim 1 or 2, wherein: The predetermined condition further includes that the corrected vehicle speed calculated by the vehicle speed correction unit is within a predetermined range relative to the vehicle speed acquired by the vehicle speed acquisition unit, or that the correction value calculated by the vehicle speed correction unit is within a predetermined range.

9. The vehicle control device according to claim 1 or 2, wherein: The vehicle speed correction unit calculates a correction value based on the relative speed when the predetermined condition is satisfied, and corrects the vehicle speed based on the correction value. The vehicle speed correction unit maintains the correction value after the correction value is calculated and until the next predetermined condition is satisfied while the ignition of the vehicle is switched from the on state to the off state.

10. A method for controlling a vehicle, the vehicle being equipped with a radar device or LiDAR capable of detecting a plurality of external objects, wherein: The vehicle control method causes a computer to execute: a vehicle speed obtaining step of obtaining a vehicle speed detected by a vehicle speed sensor mounted on the vehicle; a stationary object information acquisition step of acquiring information of a plurality of stationary objects estimated to be stationary from among the plurality of objects based on a detection result of the radar device or the LiDAR; a condition determination step of determining whether a predetermined condition is satisfied, including determining whether the estimated number of the stationary objects is greater than a predetermined number; as well as and a vehicle speed correction step of correcting the vehicle speed based on relative speeds of the plurality of stationary objects with respect to the vehicle detected by the radar device or the LiDAR when the predetermined condition is satisfied.

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