Vehicle control device, vehicle control method, and control program

Abstract

To provide a vehicle control device that can deploy airbags at the appropriate time. [Solution] The vehicle control device 1 includes an obstacle recognition unit 41 that recognizes obstacles around the vehicle 2 based on signals from a radar 11, an acceleration detection unit 43 that detects the acceleration of the vehicle 2 based on signals from an acceleration sensor 17, a collision prediction unit 44 that determines the possibility of a collision between the obstacle and the vehicle 2, and an airbag control unit 46 that deploys the airbag 23A provided in the vehicle 2 when the acceleration is above a deployment threshold. If the time for which the obstacle recognition unit 41 continues to detect an obstacle is above a detection threshold, and the collision prediction unit 44 determines that there is a possibility of a collision between the obstacle and the vehicle 2, the airbag control unit 46 lowers the deployment threshold.

Description

Technical Field

[0001] The present invention relates to a vehicle control device, a vehicle control method, and a control program.

Background Art

[0002] In recent years, efforts have been actively made to provide a sustainable transportation system that takes into account people in vulnerable positions among traffic participants. In order to further improve traffic safety and convenience towards this realization, research and development regarding collision safety performance have been carried out.

[0003] Patent Document 1 discloses a vehicle control device that performs deployment control of an airbag. The vehicle control device deploys the airbag when the lateral acceleration of the vehicle exceeds a deployment threshold value. The vehicle control device predicts the future position of the vehicle and the future position of an object, and predicts whether the object will collide with the side surface of the vehicle based on the future positions of the vehicle and the object. And when the vehicle control device predicts that the object will collide with the side surface of the vehicle, it lowers the deployment threshold value. Thereby, the airbag is deployed earlier.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] A radar may be used to detect the positions of a vehicle and an obstacle. However, in the radar, there may occur a ghost phenomenon in which an obstacle that does not actually exist is detected due to multipath reflection of radio waves. If the deployment threshold value of the airbag is lowered based on an obstacle that does not actually exist, the acceleration caused by the unevenness of the road surface may exceed the deployment threshold value, and the airbag may be deployed at an unfavorable timing.

[0006] In view of the above background, one aspect of the present invention aims to provide a vehicle control device, a vehicle control method, and a control program that can deploy airbags at an appropriate timing. [Means for solving the problem]

[0007] To solve the above problems, one aspect of the present invention provides a vehicle control device comprising: an obstacle recognition unit that recognizes obstacles around the vehicle based on signals from radar; an acceleration detection unit that detects the acceleration of the vehicle based on signals from an acceleration sensor; a collision prediction unit that determines the possibility of a collision between the obstacle and the vehicle; and an airbag control unit that deploys an airbag provided in the vehicle when the acceleration is equal to or greater than a deployment threshold, wherein the airbag control unit lowers the deployment threshold when the time the obstacle recognition unit has continued to detect the obstacle is equal to or greater than a capture threshold, and the collision prediction unit determines that there is a possibility of a collision between the obstacle and the vehicle.

[0008] Another aspect of the present invention is a vehicle control method performed by a computer, which recognizes obstacles around the vehicle based on signals from radar, detects the acceleration of the vehicle based on signals from an acceleration sensor, determines the possibility of collision between the obstacle and the vehicle, deploys an airbag provided in the vehicle if the acceleration is greater than or equal to a deployment threshold, and lowers the deployment threshold if the time for which the obstacle has been continuously detected is greater than or equal to a capture threshold and it is determined that there is a possibility of collision between the obstacle and the vehicle.

[0009] Another aspect of the present invention is a control program for causing a computer to execute a vehicle control method, which causes the computer to recognize obstacles around the vehicle based on signals from radar, detect the acceleration of the vehicle based on signals from an acceleration sensor, determine the possibility of a collision between the obstacle and the vehicle, deploy an airbag provided in the vehicle if the acceleration is greater than or equal to a deployment threshold, and lower the deployment threshold if the time the obstacle has been continuously detected is greater than or equal to a capture threshold and it is determined that there is a possibility of a collision between the obstacle and the vehicle. [Effects of the Invention]

[0010] According to the above embodiments, it is possible to provide a vehicle control device, a vehicle control method, and a control program that can deploy airbags at an appropriate timing. [Brief explanation of the drawing]

[0011] [Figure 1] Configuration diagram of a vehicle control device according to this embodiment [Figure 2] Diagram illustrating the ghosts detected by radar. [Figure 3] Graph showing the expansion threshold [Figure 4] Flowchart showing the procedure for setting the deployment threshold in the vehicle control method according to the embodiment. [Figure 5] Flowchart showing the airbag deployment control procedure in the vehicle control method according to the embodiment. [Modes for carrying out the invention]

[0012] Hereinafter, embodiments of the vehicle control device, vehicle control method, and control program will be described with reference to the drawings.

[0013] As shown in Figure 1, the vehicle control device 1 is installed in the vehicle 2. The vehicle 2 is a four-wheeled automobile. The vehicle 2 may be an autonomous vehicle or a vehicle with driver assistance functions.

[0014] Vehicle 2 has an external environment recognition device 7. The external environment recognition device 7 is a device that detects objects outside the vehicle. The external environment recognition device 7 is a sensor that detects objects outside the vehicle by capturing electromagnetic waves and light from the surroundings of Vehicle 2. The external environment recognition device 7 includes a radar 11, a LiDAR 12, and a camera 13.

[0015] Radar 11 detects the position and speed of an object by transmitting radio waves around the vehicle 2 and receiving radio waves reflected by the object. Radar 11 may be a millimeter-wave radar that utilizes millimeter waves for electromagnetic radiation. Multiple radars 11 may be installed on the vehicle 2. Radar 11 includes at least a forward radar that detects objects in the area in front of the vehicle 2. Radar 11 may also include a rear radar that detects obstacles in the area behind the vehicle 2. Radar 11 may also include a plurality of corner radars that detect obstacles in the areas to the right front, left front, right rear, and left rear of the vehicle 2.

[0016] One of the radars 11, the forward radar, is preferably located in the center of the front end of the vehicle 2 in the left-right direction and transmits radio waves forward. The forward radar may be located, for example, behind an emblem located on the front end of the vehicle 2. The emblem may be made of a resin material that transmits radio waves. The forward radar transmits radio waves to the left and right at a predetermined angular width with respect to a center line extending forward from the vehicle 2. The angular width may be set, for example, to 20° to the left and 15° to the right. For example, the forward radar may transmit radio waves within a range of 30m to the left and right at a distance of 150m ahead. The forward radar may also transmit radio waves vertically at a predetermined angular width with respect to the center line.

[0017] Radar 11 transmits radio waves in pulses and measures the time it takes for the reflected waves, which have been reflected by an object, to return. Radar 11 also detects the intensity of the reflected waves and uses the directivity of its antenna to detect the angle at which the object is located. Furthermore, Radar 11 uses the Doppler effect to measure the velocity of the object based on the difference between the frequency of the reflected waves and the frequency of the transmitted waves. Radar 11 outputs radar data containing this information.

[0018] The lidar 12 irradiates light such as infrared light around the vehicle 2 and captures the reflected light, thereby detecting the position (distance and direction) of an object. The lidar 12 may detect obstacles existing in the area in front of the vehicle 2.

[0019] The camera 13 images the surroundings of the vehicle 2 and obtains an image of the surroundings of the vehicle 2. The image of the surroundings of the vehicle 2 includes surrounding vehicles (surrounding moving objects), pedestrians, guardrails, curbs, walls, median strips, road shapes, lane lines, road signs drawn on the road, etc. existing around the vehicle 2. The camera 13 may be, for example, a digital camera using a solid-state imaging device such as a CCD or a CMOS. The camera 13 includes a front camera that images at least the area in front of the vehicle 2. The camera 13 may include a rear camera that images the rear of the vehicle 2 and a pair of side cameras that image the left and right sides of the vehicle 2. The camera 13 may be, for example, a stereo camera.

[0020] The vehicle 2 has a vehicle sensor 15. The vehicle sensor 15 includes a vehicle speed sensor 16 that detects the speed of the vehicle 2 and an acceleration sensor 17 that detects acceleration. The vehicle sensor 15 may further include a yaw rate sensor that detects the angular velocity around the vertical axis, a direction sensor that detects the orientation of the vehicle 2, etc. The vehicle speed sensor 16 includes four wheel speed sensors provided on the four wheels. Each wheel speed sensor detects the rotational speed of the corresponding wheel. The wheel speed sensor may be, for example, a magnetic rotary encoder composed of a hall element and a permanent magnet.

[0021] The acceleration sensor 17 should at least detect the acceleration in the front-rear direction and the acceleration in the up-down direction of the vehicle 2. Further, the acceleration sensor 17 may detect the acceleration in the left-right direction of the vehicle 2.

[0022] The vehicle sensor 15 may have a stroke sensor 18 capable of detecting the vertical position of each wheel with respect to the vehicle body. The stroke sensor 18 is provided on a suspension device provided between the vehicle body and the wheel, expands and contracts according to the movement of the suspension device, and outputs a signal according to the length.

[0023] Vehicle 2 is equipped with a GNSS (Global Navigation Satellite System) receiver 21. The GNSS receiver 21 determines the position (latitude and longitude) of vehicle 2 based on signals received from artificial satellites (positioning satellites).

[0024] Vehicle 2 is equipped with an HMI22 (Human Machine Interface). The HMI22 provides various information to the occupants through displays and voice prompts, and also accepts input operations from the occupants. The HMI22 may include, for example, a touch panel display and speakers.

[0025] Vehicle 2 is equipped with an airbag unit 23 to protect occupants in the event of a collision. The airbag unit 23 comprises an airbag 23A and an inflator 23B that inflates the airbag 23A. The inflator 23B receives an electrical signal from the vehicle control device 1, generates expansion gas, and inflates the airbag 23A. The airbag unit 23 may be installed in the steering wheel, instrument panel, front pillar, middle pillar, rear pillar of vehicle 2, or on the side of the seat back of the seats.

[0026] The vehicle control device 1 is a computer having a processor 31 and a memory 32 that is communicatively connected to the processor 31. The processor 31 may include at least one of the following as its core: a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), or a RISC (Reduced Instruction Set Computer). The memory 32 stores control programs executed by the processor 31 and various data. The memory 32 may include at least one of volatile memory and non-volatile memory. The volatile memory may be, for example, DRAM (Dynamic Random Access Memory) or SRAM (Static Random Access Memory). The non-volatile memory may be an SSD (Solid State Drive), flash memory, magnetic disk storage device, or optical disk storage device. At least a part of the vehicle control device 1 may be implemented by hardware such as an LSI (Large Scale Integration), ASIC (application specific integrated circuit), or FPGA (field-programmable gate array), or by a combination of software and hardware. The vehicle control device 1 may be composed of a single piece of hardware, or it may be composed of multiple pieces of hardware that can communicate with each other. Part of the vehicle control device 1 may be composed of an external server located outside the vehicle 2.

[0027] The processor 31 implements various applications by executing programs stored in memory 32. Programs may be stored on removable recordable media such as DVDs or CD-ROMs, and installed in memory 32 when the recordable media is read by a reader. Alternatively, programs may be downloaded to and installed in memory 32 via a communication network such as the internet.

[0028] Memory 32 should preferably store map information. The map information should preferably be high-resolution map information. The map information should include road information such as the type of road (expressway, toll road, national road, prefectural road), the number of lanes, the center position of each lane (3D coordinates including longitude, latitude, and height), the shape of road markings such as road markings and lane boundaries, the presence or absence of sidewalks, curbs, fences, etc., the location of intersections, the locations of lane merging and branching points, the area of ​​emergency parking zones, the width of each lane, and road signs. In addition, the map information may also include traffic regulation information, address information (address and postal code), facility information, telephone number information, etc.

[0029] The processor 31 functions as an obstacle recognition unit 41, a vehicle position recognition unit 42, an acceleration detection unit 43, a collision prediction unit 44, a road surface condition acquisition unit 45, and an airbag control unit 46 by executing a program stored in the memory 32.

[0030] The obstacle recognition unit 41 recognizes the surrounding environment of the vehicle 2. Based on the detection results of the external environment recognition device 7, the obstacle recognition unit 41 recognizes the surrounding environment (external world), including obstacles located around the vehicle 2, the shape of the road, the presence or absence of sidewalks, road markings, etc. Obstacles include, for example, guardrails, utility poles, surrounding vehicles, and people such as pedestrians. From the detection results of the external environment recognition device 7, the obstacle recognition unit 41 can acquire the status of surrounding vehicles, such as their position, speed, and acceleration.

[0031] In this embodiment, the obstacle recognition unit 41 recognizes obstacles around the vehicle 2 based on signals from the radar 11. The obstacle recognition unit 41 acquires the position and speed of the obstacles based on the radar data. The position of the obstacle may be expressed as the distance between the vehicle 2 and the obstacle, and the angle of the obstacle relative to the vehicle 2. The obstacle recognition unit 41 may recognize targets whose reflected wave intensity is above a predetermined value as obstacles.

[0032] The obstacle recognition unit 41 may mistakenly identify an obstacle as existing in a location where it does not actually exist due to multiple reflections of the reflected wave. This phenomenon is called the ghost phenomenon of the radar 11. For example, as shown in Figure 2, if there is a surrounding vehicle 100 as an obstacle in front of vehicle 2, and a wall 101 such as a sound barrier is present on the side of the road, the ghost phenomenon may occur. The proper reflection path 102 of radio waves is a straight line connecting vehicle 2 and the surrounding vehicle 100. However, if multiple reflections occur, the reflected wave reflected by the surrounding vehicle 100 is reflected again by the wall 101 before being received by the radar 11. In this case, since the direction of reception of the reflected wave is the direction in which the reflection point 104 of the wall 101 is located, the radar mistakenly identifies a ghost 105, which is an obstacle that does not actually exist, as existing on a virtual line 106 connecting vehicle 2 and the reflection point 104 of the wall 101. Furthermore, due to multiple reflections, the time it takes for radio waves to be received is extended, causing ghost 105 to be mistakenly perceived as being located behind wall 101.

[0033] Such ghosts 105 disappear due to changes in the relative position between the obstacle and the wall 101, changes in the shape of the wall 101, or the disappearance of the wall 101. Therefore, the duration for which ghosts 105 persist is relatively short. In this embodiment, the obstacle recognition unit 41 measures the time for which it continues to detect the obstacle. The obstacle recognition unit 41 then determines that the obstacle is real, i.e., not a ghost, if the time for which it continues to detect the obstacle (capture time) is equal to or greater than the capture threshold. The capture threshold is, for example, 0.5 to 3.0 seconds, preferably 2.0 to 3.0 seconds.

[0034] The obstacle recognition unit 41 may lower the detection threshold as the speed of the obstacle or the speed of the vehicle 2 increases. In other words, in situations where the speed of the obstacle or the vehicle 2 is high and a higher level of safety is required, the obstacle is determined to be a real obstacle at an earlier stage. The obstacle recognition unit 41 may lower the detection threshold as the relative speed between the obstacle and the vehicle 2 increases.

[0035] The vehicle position recognition unit 42 recognizes the position of vehicle 2. The vehicle position recognition unit 42 may recognize the position of vehicle 2 based on the GNSS signal received by the GNSS receiver 21.

[0036] The acceleration detection unit 43 detects the acceleration of the vehicle 2 based on the signal from the acceleration sensor 17. The acceleration detection unit 43 may include longitudinal acceleration, lateral acceleration, and vertical acceleration of the vehicle 2.

[0037] The collision prediction unit 44 determines the possibility of a collision between the obstacle and the vehicle 2. The collision prediction unit 44 determines that there is a possibility of a collision between the obstacle and the vehicle 2 if the time to collision (TTC) between the obstacle and the vehicle 2 is less than or equal to the collision threshold. The collision prediction unit 44 may determine the possibility of a collision for obstacles detected by the obstacle recognition unit 41 that are within a predetermined distance from the vehicle 2. The collision time may be calculated by dividing the distance between the obstacle and the vehicle 2 by the relative speed between the obstacle and the vehicle 2.

[0038] The road surface condition acquisition unit 45 acquires the unevenness of the road surface based on signals from the acceleration sensor 17 or the stroke sensor 18. The unevenness of the road surface may be represented, for example, as a numerical value in multiple stages. The numerical value should increase when the unevenness of the road surface is large. The road surface condition acquisition unit 45 may increase the numerical value corresponding to the unevenness of the road surface in accordance with the magnitude of the vertical acceleration. In addition, the road surface condition acquisition unit 45 may increase the numerical value corresponding to the unevenness of the road surface in accordance with the magnitude of the change in the stroke sensor 18. The road surface condition acquisition unit 45 may determine that the road surface is a rough road if the numerical value corresponding to the unevenness of the road surface is equal to or greater than a predetermined rough road determination threshold.

[0039] The airbag control unit 46 deploys the airbag 23A installed in the vehicle 2 when the acceleration is equal to or greater than the deployment threshold. When the acceleration is equal to or greater than the deployment threshold, the airbag control unit 46 transmits an electrical signal to the inflator 23B of the airbag unit 23. The inflator 23B receives the electrical signal from the airbag control unit 46, generates expansion gas, and inflates the airbag 23A. The acceleration may be the longitudinal acceleration, lateral acceleration, or vertical acceleration of the vehicle 2.

[0040] If the time the obstacle recognition unit 41 has continuously detected an obstacle exceeds the detection threshold, and the collision prediction unit 44 determines that there is a possibility of collision between the obstacle and the vehicle 2, the airbag control unit 46 lowers the deployment threshold. In other words, if an obstacle that has been continuously detected by the obstacle recognition unit 41 for a period exceeding the detection threshold has a possibility of colliding with the vehicle 2, the airbag control unit 46 lowers the deployment threshold. An obstacle that has been continuously detected by the obstacle recognition unit 41 for a period exceeding the detection threshold is presumed to be a real obstacle, not a ghost. By lowering the deployment threshold, the deployment threshold can be exceeded with a smaller acceleration, and the airbag 23A will deploy earlier.

[0041] If the time the obstacle recognition unit 41 continues to detect an obstacle is greater than or equal to the detection threshold, and the collision prediction unit 44 determines that there is a possibility of collision between the obstacle and the vehicle 2, the airbag control unit 46 may lower the deployment threshold more significantly the longer the time the obstacle recognition unit 41 continues to detect the obstacle. The longer the detection time, the higher the probability that the obstacle is real. In other words, the longer the detection time, the lower the probability that the obstacle is a ghost. The detection time can be said to be a value corresponding to the probability that the obstacle is real. For example, as shown in Figure 3, if the detection time is greater than or equal to the detection threshold and less than the first determination value, the airbag control unit 46 may set the deployment threshold to the first reduction threshold. Also, if the detection time is greater than or equal to the first determination value, the airbag control unit 46 may set the deployment threshold to the second reduction threshold. The first determination value is set to a time longer than the detection threshold. The first reduction threshold is set to a value lower than the initial value, and the second reduction threshold is set to a value lower than the first reduction threshold. The initial value is set to be higher than the maximum value of the acceleration 110 that occurs when the door of the vehicle 2 is closed. The first reduction threshold is set lower than the maximum acceleration that occurs when the doors of vehicle 2 are closed. The first and second reduction thresholds should be set to values ​​greater than the vertical acceleration 111 applied to vehicle 2 when driving on rough roads. By changing the deployment threshold from its initial value to the first or second reduction threshold, the acceleration 112 caused by the collision will exceed the deployment threshold more quickly.

[0042] If the road surface condition acquisition unit 45 detects significant irregularities in the road surface, the airbag control unit 46 may maintain the deployment threshold even if the time the obstacle recognition unit 41 continues to detect an obstacle is greater than or equal to the detection threshold, and the collision prediction unit 44 determines that there is a possibility of collision between the obstacle and the vehicle 2. In this embodiment, if the road surface is significantly irregular, lowering the deployment threshold may cause the acceleration due to the vertical acceleration caused by the irregularities in the road surface to exceed the deployment threshold, potentially causing the airbag 23A to deploy. Therefore, by prohibiting the lowering of the deployment threshold in such situations, malfunction of the airbag 23A can be suppressed.

[0043] Next, the vehicle control method performed by the vehicle control device 1 will be described with reference to Figures 4 and 5. Figure 4 is a flowchart showing the procedure for setting the deployment threshold. The vehicle control device 1 repeatedly performs the procedure for setting the deployment threshold at predetermined time intervals. First, the vehicle control device 1 detects obstacles based on radar data acquired from the radar 11 (ST1). The number of obstacles detected may be zero or one or more.

[0044] Next, the vehicle control device 1 sets a capture threshold based on the speed of vehicle 2 (ST2). It is desirable that the capture threshold decreases as the speed of vehicle 2 increases. The vehicle control device 1 may use a map in which the relationship between the speed of vehicle 2 and the capture threshold is predetermined to set the capture threshold corresponding to the speed of vehicle 2.

[0045] Next, the vehicle control device 1 extracts first extracted obstacles from among the detected obstacles whose detection time is equal to or greater than the detection threshold (ST3). The first extracted obstacles are likely to be real and not ghosts.

[0046] Next, the vehicle control device 1 extracts obstacles from the first extracted obstacles that are less than or equal to a predetermined value in distance from the vehicle 2 as second extracted obstacles (ST4). Subsequently, the vehicle control device 1 determines whether or not the second extracted obstacles exist (ST5).

[0047] If a second detected obstacle exists (ST5: Yes), the vehicle control device 1 determines whether the road surface on which the vehicle 2 is traveling is a rough road (ST6). The vehicle control device 1 obtains the surface irregularities of the road based on the vertical acceleration of the vehicle 2, and determines that the road surface is a rough road if the numerical value of the surface irregularities is equal to or greater than the rough road determination value.

[0048] If the road surface is not rough (ST6: No), the vehicle control device 1 calculates the collision margin time between each of the second extracted obstacles and the vehicle 2 (ST7).

[0049] Next, the vehicle control device 1 determines whether the smallest value among the calculated collision margin times is less than or equal to the collision threshold (ST8).

[0050] If the collision margin time is less than or equal to the collision threshold (ST8: Yes), the vehicle control device 1 determines whether the detection time of the obstacle is less than the first determination value (ST9). If the detection time of the obstacle is less than the first determination value (ST9: Yes), the vehicle control device 1 sets the first reduction threshold to the deployment threshold (ST10). If the detection time of the obstacle is equal to or greater than the first determination value (ST9: No), the vehicle control device 1 sets the second reduction threshold to the deployment threshold (ST11).

[0051] If there is no second detection obstacle (ST5: No), if the road surface is rough (ST6: Yes), or if the collision margin time is greater than the collision threshold (ST8: No), the vehicle control device 1 sets an initial value for the deployment threshold (ST12).

[0052] Figure 5 is a flowchart showing the deployment control procedure for airbag 23A. The vehicle control device 1 repeats the airbag 23A deployment control procedure shown in Figure 5 at predetermined time intervals. The vehicle control device 1 determines whether the acceleration of the vehicle 2 acquired by the acceleration sensor 17 is equal to or greater than the deployment threshold (ST21). The acceleration of the vehicle 2 may be longitudinal acceleration, lateral acceleration, or vertical acceleration. The deployment threshold is set based on the deployment threshold setting procedure shown in Figure 4.

[0053] If the acceleration of vehicle 2 is greater than or equal to the deployment threshold (ST21: Yes), the vehicle control device 1 deploys the airbag 23A (ST22). Specifically, the vehicle control device 1 outputs an electrical signal to the inflator 23B of the airbag unit 23, causing the inflator 23B to generate expansion gas.

[0054] If the acceleration of vehicle 2 is below the deployment threshold (ST21: No), the process proceeds to return.

[0055] According to the above embodiment, if there is a high probability that the obstacle detected by the radar 11 is a ghost, the deployment threshold is not lowered. Therefore, it is prevented that the airbag 23A will deploy at the wrong time due to acceleration caused by unevenness in the road surface. On the other hand, if there is a high probability that the obstacle detected by the radar 11 is real and there is a possibility of collision, the deployment threshold is lowered, causing the airbag 23A to deploy earlier.

[0056] The embodiments are not limited to the above configuration and can be broadly modified. For example, in the flowchart of Figure 4, the determination of whether the road surface is rough or not in step ST6 may be omitted. Also, the process of setting the capture threshold based on the speed of vehicle 2 in step ST2 may be omitted, and a pre-set fixed value may be used as the capture threshold.

[0057] The above embodiments may also be described as follows:

[0058] In one embodiment, the vehicle control device 1 includes an obstacle recognition unit 41 that recognizes obstacles around the vehicle 2 based on signals from a radar 11, an acceleration detection unit 43 that detects the acceleration of the vehicle 2 based on signals from an acceleration sensor 17, a collision prediction unit 44 that determines the possibility of a collision between the obstacle and the vehicle 2, and an airbag control unit 46 that deploys an airbag 23A provided in the vehicle 2 when the acceleration is equal to or greater than a deployment threshold, wherein the time for which the obstacle recognition unit 41 continues to detect the obstacle is equal to or greater than a capture threshold, and the collision prediction unit 44 determines that there is a possibility of a collision between the obstacle and the vehicle 2, the airbag control unit 46 lowers the deployment threshold.

[0059] According to this embodiment, a vehicle control device 1 can be provided that can deploy the airbag 23A at the appropriate timing. If there is a high probability that the obstacle detected by the radar 11 is a ghost, the deployment threshold is not lowered. Therefore, it is prevented that the airbag 23A will deploy at the wrong timing due to acceleration caused by unevenness in the road surface. On the other hand, if there is a high probability that the obstacle detected by the radar 11 is real and there is a possibility of collision, the deployment threshold is lowered, causing the airbag 23A to deploy earlier.

[0060] In the above embodiment, the collision prediction unit 44 may determine that there is a possibility of collision between the obstacle and the vehicle 2 when the collision margin time between the obstacle and the vehicle 2 is less than or equal to the collision threshold.

[0061] According to this embodiment, the possibility of collision between the obstacle and the vehicle 2 can be determined based on the collision margin time.

[0062] In the above embodiment, the obstacle recognition unit 41 may lower the detection threshold as the speed of the obstacle increases or as the speed of the vehicle 2 increases.

[0063] According to this embodiment, in situations where the speed of the obstacle or vehicle 2 is high and a higher level of safety is required, the obstacle is determined to be a real obstacle at an earlier stage. This improves safety.

[0064] In the above embodiment, if the time for which the obstacle recognition unit 41 continues to detect the obstacle is equal to or greater than the detection threshold, and the collision prediction unit 44 determines that there is a possibility of collision between the obstacle and the vehicle 2, the airbag control unit 46 may lower the deployment threshold more significantly the longer the time for which the obstacle recognition unit 41 continues to detect the obstacle.

[0065] According to this embodiment, the higher the probability of an obstacle being present, the lower the deployment threshold can be, allowing for a quicker response to collisions.

[0066] In the above embodiment, the system includes a road surface condition acquisition unit 45 that acquires road surface irregularities based on signals from sensors, and if the road surface irregularities detected by the road surface condition acquisition unit 45 are large, the airbag control unit 46 may maintain the deployment threshold even if the time the obstacle recognition unit 41 continues to detect the obstacle is greater than or equal to the capture threshold, and the collision prediction unit 44 determines that there is a possibility of collision between the obstacle and the vehicle 2.

[0067] According to this embodiment, a reduction in the deployment threshold can be prevented when the road surface is uneven. This prevents the airbag 23A from deploying due to acceleration caused by the unevenness of the road surface.

[0068] Another embodiment is a vehicle control method performed by a computer, which recognizes obstacles around the vehicle 2 based on signals from radar 11, detects the acceleration of the vehicle 2 based on signals from acceleration sensor 17, determines the possibility of collision between the obstacle and the vehicle 2, deploys an airbag 23A provided in the vehicle 2 if the acceleration is greater than or equal to a deployment threshold, and lowers the deployment threshold if the time for which the obstacle has been continuously detected is greater than or equal to a capture threshold and it is determined that there is a possibility of collision between the obstacle and the vehicle 2.

[0069] According to this embodiment, a vehicle control method can be provided that enables the airbag 23A to be deployed at an appropriate timing.

[0070] Another embodiment is a control program for causing a computer to execute a vehicle control method, which causes the computer to recognize obstacles around the vehicle 2 based on signals from radar 11, detect the acceleration of the vehicle 2 based on signals from acceleration sensor 17, determine the possibility of collision between the obstacle and the vehicle 2, deploy the airbag 23A provided in the vehicle 2 if the acceleration is above a deployment threshold, and lower the deployment threshold if the time the obstacle has been continuously detected is above a capture threshold and it is determined that there is a possibility of collision between the obstacle and the vehicle 2.

[0071] According to this embodiment, it is possible to provide a control program for executing a vehicle control method that can deploy the airbag 23A at an appropriate timing. [Explanation of symbols]

[0072] 1: Vehicle control system 2: Vehicles 11: Radar 16: Vehicle speed sensor 17: Accelerometer 18: Stroke sensor 21: GNSS receiver 23: Airbag Unit 23A: Airbag 23B: Inflator 31: Processor 32: Memory 41: Obstacle Recognition Unit 42: Vehicle position recognition unit 43: Acceleration detection unit 44: Collision prediction unit 45: Road surface condition acquisition unit 46: Airbag control unit

Claims

1. A vehicle control device, An obstacle recognition unit that recognizes obstacles around the vehicle based on signals from radar, An acceleration detection unit that detects the acceleration of the vehicle based on a signal from an acceleration sensor, A collision prediction unit that determines the possibility of a collision between the aforementioned obstacle and the aforementioned vehicle, The vehicle has an airbag control unit that deploys the airbag provided in the vehicle when the acceleration is equal to or greater than a deployment threshold, A vehicle control device in which, when the time for which the obstacle recognition unit continues to detect the obstacle is greater than or equal to the detection threshold, and the collision prediction unit determines that there is a possibility of collision between the obstacle and the vehicle, the airbag control unit lowers the deployment threshold.

2. The vehicle control device according to claim 1, wherein the collision prediction unit determines that there is a possibility of collision between the obstacle and the vehicle when the collision margin time between the obstacle and the vehicle is less than or equal to a collision threshold.

3. The vehicle control device according to claim 1, wherein the obstacle recognition unit lowers the detection threshold as the speed of the obstacle increases or the speed of the vehicle increases.

4. The vehicle control device according to claim 1, wherein if the time for which the obstacle recognition unit continues to detect the obstacle is equal to or greater than the detection threshold, and the collision prediction unit determines that there is a possibility of collision between the obstacle and the vehicle, the airbag control unit lowers the deployment threshold more significantly the longer the time for which the obstacle recognition unit continues to detect the obstacle.

5. It has a road surface condition acquisition unit that acquires the unevenness of the road surface based on signals from sensors, The vehicle control device according to claim 1, in which the road surface condition acquisition unit detects large irregularities in the road surface, the time during which the obstacle recognition unit continues to detect the obstacle is greater than or equal to the capture threshold, and even if the collision prediction unit determines that there is a possibility of collision between the obstacle and the vehicle, the airbag control unit maintains the deployment threshold.

6. A vehicle control method performed by a computer, Based on signals from radar, the system recognizes obstacles around the vehicle. The acceleration of the vehicle is detected based on the signal from the acceleration sensor. Determine the possibility of a collision between the obstacle and the vehicle. When the acceleration exceeds the deployment threshold, the airbags provided in the vehicle are deployed. A vehicle control method that lowers the deployment threshold when it is determined that the time for which the obstacle is continuously detected is greater than or equal to the detection threshold, and that there is a possibility of collision between the obstacle and the vehicle.

7. A control program for causing a computer to execute a vehicle control method, Based on signals from radar, the system recognizes obstacles around the vehicle. Based on the signal from the acceleration sensor, the acceleration of the vehicle is detected. Determine the possibility of a collision between the obstacle and the vehicle. When the acceleration exceeds the deployment threshold, the airbags provided in the vehicle are deployed. A control program that lowers the deployment threshold when it is determined that the time for which the obstacle is continuously detected is greater than or equal to the detection threshold, and that there is a possibility of collision between the obstacle and the vehicle.

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