Vehicle control device

Abstract

The present application provides a vehicle control device capable of improving safety at the time of a vehicle collision. The vehicle control device (10) has a speed calculation section (12) that calculates a vehicle speed at the time of a collision in the case where a collision of a vehicle (100) is detected by a collision detection sensor (9), and a driving support control section (14) that performs automatic brake control based on the vehicle speed at the time of a collision calculated by the speed calculation section (12), the speed calculation section (12) calculating the vehicle speed at the time of a collision based on the highest detection value among detection values of a plurality of wheel speed sensors (8) of respective wheels in the case where a brake pedal (2) is depressed at the time of a collision of the vehicle (100).

Description

Technical Field

[0001] This invention relates to vehicle control devices. Background Technology

[0002] Regarding the control of collisions involving vehicles in motion, for example, the technology described in Patent Document 1 is known. That is, Patent Document 1 describes a method in which, when a collision is detected by a collision detection unit, a braking force increase unit performs automatic braking control to increase the braking force of the vehicle.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2016-7991 Summary of the Invention

[0006] While Patent Document 1 describes automatic braking control during a vehicle collision as described above, it does not describe the calculation of vehicle speed during automatic braking control, leaving room for further improvement in safety during a collision.

[0007] Therefore, the objective of this invention is to provide a vehicle control device that can improve safety during a vehicle collision.

[0008] To address the aforementioned issues, the vehicle control device of the present invention is characterized by comprising: a speed calculation unit that calculates the vehicle speed at the time of collision when a vehicle collision is detected by a collision detection sensor; and a driver support control unit that performs automatic braking control based on the vehicle speed at the time of collision calculated by the speed calculation unit. The speed calculation unit calculates the vehicle speed at the time of collision based on the highest detection value among the detection values ​​of wheel speed sensors for each of the plurality of wheels when the brake pedal is depressed during a vehicle collision. Further details are described in the embodiments.

[0009] Invention Effects

[0010] According to the present invention, a vehicle control device capable of improving safety during a vehicle collision can be provided. Attached Figure Description

[0011] Figure 1 It is a functional block diagram of the vehicle control device including the first embodiment.

[0012] Figure 2A This is an explanatory diagram showing an example of the moment a vehicle collision occurs in the vehicle control device of the first embodiment.

[0013] Figure 2B This is an explanatory diagram showing an example of what happens immediately after a vehicle collision in the vehicle control device of the first embodiment.

[0014] Figure 3 This is an explanatory diagram showing the change in wheel speed in the vehicle control device of the first embodiment during the time including the time when a collision occurs.

[0015] Figure 4 This is a flowchart illustrating the processing of the vehicle control device according to the first embodiment.

[0016] Figure 5 This is a timing diagram of the automatic braking control in the vehicle control device of the first embodiment regarding a vehicle collision.

[0017] Figure 6 This is a flowchart illustrating the processing of the vehicle control device according to the second embodiment.

[0018] Explanation of reference numerals in the attached figures

[0019] 1 Accelerator pedal

[0020] 2 Brake pedal

[0021] 3 steering wheels

[0022] 4 Accelerator pedal operation sensor

[0023] 5. Brake pedal operation sensor

[0024] 6 steering angle sensors

[0025] 7. Steering torque sensor

[0026] 8 wheel speed sensors

[0027] 9 collision detection sensors

[0028] 10 Vehicle control devices

[0029] 11 Storage Department

[0030] 12 Speed ​​Calculation Department

[0031] 13 Driving Control Department

[0032] 14 Driving Support Control Unit

[0033] 21 Driving force output device

[0034] 22 Braking device

[0035] 23 Steering System

[0036] 100 vehicles Detailed Implementation

[0037] Implementation Method 1

[0038] Figure 1This is a functional block diagram of the vehicle control device 10 according to the first embodiment.

[0039] Figure 1 The vehicle 100 shown is a moving body that travels under the control of a vehicle control device 10. The vehicle 100 serves as a driving control element operated by a driver. Figure 1 The diagram shows an accelerator pedal 1, a brake pedal 2, and a steering wheel 3. The accelerator pedal 1 is the pedal pressed by the driver to generate the driving force of the vehicle 100. The brake pedal 2 is the pedal pressed by the driver to generate the braking force of the vehicle 100. The steering wheel 3 is a steering handle used by the driver to steer the vehicle.

[0040] In addition, the vehicle 100 includes an accelerator pedal operation amount sensor 4, a brake pedal operation amount sensor 5, a steering angle sensor 6, and a steering torque sensor 7 as sensors for detecting the operation amount of the aforementioned driving operation elements. The accelerator pedal operation amount sensor 4 is a travel sensor that detects the operation amount (depression) of the accelerator pedal 1. For example... Figure 1 As shown, the operation amount θa of the accelerator pedal 1 is output from the accelerator pedal operation amount sensor 4 to the vehicle control device 10. The brake pedal operation amount sensor 5 is a travel sensor that detects the operation amount (depression amount) of the brake pedal 2. Figure 1 As shown, the operation amount θb of the brake pedal 2 is output from the brake pedal operation amount sensor 5 to the vehicle control device 10.

[0041] In addition, brake pedal 2 is provided with Figure 1 The brake switch 2a is shown. When the brake pedal 2 is depressed, it outputs, for example, an ON signal as a brake switch signal Sb sent from the brake switch 2a to the vehicle control device 10. Conversely, when the brake pedal 2 is not depressed, it outputs, for example, an OFF signal as a brake switch signal Sb sent from the brake switch 2a to the vehicle control device 10.

[0042] Steering angle sensor 6 is used to detect the steering angle of steering wheel 3. Steering torque sensor 7 is used to detect the steering torque of steering wheel 3. For example... Figure 1 As shown, the steering angle θc of the steering wheel 3 is output to the vehicle control device 10 from the steering angle sensor 6. Additionally, the steering torque Nc of the steering wheel 3 is output to the vehicle control device 10 from the steering torque sensor 7.

[0043] Additionally, the vehicle 100 includes wheel speed sensors 8 and collision detection sensors 9. The wheel speed sensors 8 are sensors that detect the individual wheel speeds (rotational speeds per unit time) of the multiple wheels (not shown) of the vehicle 100. For example, in a four-wheeled vehicle 100, four wheel speed sensors 8 are provided to detect the wheel speeds of the right front wheel, left front wheel, right rear wheel, and left rear wheel respectively. Furthermore, the wheel speed v of the right front wheel at each moment... FR Based on this, the wheel speed v of the left front wheel FL The wheel speed v of the right rear wheel RR The wheel speed vRL of the left rear wheel is output from the wheel speed sensor 8 to the vehicle control device 10.

[0044] Furthermore, the two subscripts in the Roman numeral 'v' indicating wheel speed indicate the wheel's position. Specifically, the two subscripts, in their order of appearance, are combinations of 'Front' or 'Rear' and 'Left' or 'Right' to indicate the wheel's position.

[0045] Figure 1 The collision detection sensor 9 shown is a sensor for detecting collisions with the vehicle 100. Such a collision detection sensor 9 can be, for example, a pressure sensor, but is not limited to this. Furthermore, in addition to the front surface of the vehicle 100, multiple collision detection sensors 9 can be installed on the right and left sides, rear surface, etc. Upon detecting a collision with the vehicle 100, a predetermined collision detection signal Sd is output from the collision detection sensor 9 to the vehicle control device 10. Moreover, the object that is the target of a collision with the vehicle 100 varies depending on the situation, but in addition to moving objects from other vehicles, it can also include guardrails and utility poles.

[0046] In addition, although Figure 1 Although the illustration is omitted, the vehicle 100 is also equipped with a G-sensor to detect the acceleration of the vehicle 100, a yaw sensor to detect the yaw rate (rotational speed about the vertical axis) of the vehicle 100, and an orientation sensor to detect the orientation of the vehicle 100. In addition, as an HMI (Human Machine Interface) for providing various information to the occupants of the vehicle 100 or accepting occupant-based input operations, it also includes a display screen, a speaker, a buzzer, a touch panel, and buttons.

[0047] in addition, Figure 1 The vehicle 100 shown, in addition to the above-described configuration, also includes a vehicle control device 10, a driving force output device 21, a braking device 22, and a steering device 23.

[0048] The vehicle control unit 10, for example, is an ECU (Electronic Control Unit), which performs prescribed processing based on signals input from the aforementioned sensors. Figure 1 As shown, the vehicle control device 10, in addition to having a storage unit 11, also has a speed calculation unit 12, a driving control unit 13, and a driving support control unit 14.

[0049] Although not shown in the figure, the storage unit 11 includes non-volatile memory such as ROM (Read Only Memory) and HDD (Hard Disk Drive), and volatile memory such as RAM (Random Access Memory) and registers. In addition to the prescribed program, the storage unit 11 also stores the detection values ​​of the aforementioned sensors. Furthermore, for example, the program stored in the non-volatile memory is read and expanded in the volatile memory, and the CPU (Central Processing Unit) executes the prescribed processing. The functional configuration based on this processing will be described in turn.

[0050] The speed calculation unit 12 calculates the wheel speed v based on the wheel speed input from the wheel speed sensor 8. FR v FL v RR v RL To calculate the vehicle speed (the speed of vehicle 100). For example, while vehicle 100 is moving, the speed calculation unit 12 calculates the speed based on the wheel speed v. FR v FL v RR v RL The vehicle speed is calculated by averaging the detected values. Additionally, when a vehicle collides at 100 degrees, the vehicle speed is calculated using other methods, which will be explained later.

[0051] The driving control unit 13 controls the driving of the vehicle 100. That is to say, in addition to the operation of the accelerator pedal 1 and the brake pedal 2, the driving control unit 13 also controls the driving force output device 21, the braking device 22 and the steering device 23 according to the steering angle and steering torque of the steering wheel 3.

[0052] In the event of a collision involving the vehicle 100, the driver support control unit 14 controls at least one of the driving drive output device 21, braking device 22, and steering device 23, even when the driving operation elements (acceleration, braking, and steering wheel 3) are not operated. Furthermore, in situations where the vehicle 100's movement is unstable, the driver support control unit 14 performs prescribed controls to suppress wheel slippage and lock-up, thus stabilizing the vehicle 100's movement. The specific processing of the driver support control unit 14 will be described later.

[0053] The driving force output device 21 applies a prescribed driving force (torque) to the drive wheels of the vehicle 100 based on commands from the vehicle control device 10. Furthermore, the source of the driving force can be an internal combustion engine such as a diesel engine or a gasoline engine, or an electric motor. Alternatively, a combination of an internal combustion engine and an electric motor can be used as the source of the driving force. For the power supply of the electric motor, electricity generated by a generator connected to the internal combustion engine can be used, or electricity discharged from a secondary battery or fuel cell can be used.

[0054] The braking device 22 generates braking force on the vehicle 100 based on commands from the vehicle control device 10. Although not shown, the braking device 22 typically includes, for example, a disc brake that applies braking force to the wheels, a hydraulic cylinder that generates hydraulic pressure to brake the disc brake, and an electric motor that moves the piston of the hydraulic cylinder. For example, when the vehicle 100 is in motion, if the driver depresses the brake pedal 2, the electric motor is controlled to generate a predetermined hydraulic pressure (brake hydraulic pressure) corresponding to the amount of pressure applied by the hydraulic cylinder. Furthermore, although detailed later, in the event of a collision involving the vehicle 100, the vehicle control device 10 performs predetermined automatic braking control.

[0055] The steering system 23 steers the steering wheels (wheels) based on commands from the vehicle control device 10. Although not shown, the steering system 23 comprises a shaft that rotates with the operation of the steering wheel 3, a rack and pinion mechanism mounted on the shaft, and a steering motor that applies force to the rack and pinion mechanism to change the orientation of the steering wheels. Next, before explaining the specific control during a collision of the vehicle 100, the appearance of the vehicle 100 during a collision and the changes in the speed of each wheel will be described.

[0056] Figure 2A This is an explanatory diagram illustrating an example of what happens at the moment a vehicle 100 collision occurs.

[0057] also, Figure 2A The straight arrows in the diagram represent the velocity vectors of vehicle 100 (this vehicle) and other vehicles 200. Additionally, Figure 2A The dashed lines in the diagram represent the movement trajectories of vehicle 100 (this vehicle) and other vehicles 200.

[0058] exist Figure 2A In the example, vehicle 100 (this vehicle) is traveling on road R1, while another vehicle 200 is traveling on another road R2 that intersects road R1 in a T-shape. Furthermore, as shown in the collision point Q1, the other vehicle 200 collides with the left side of vehicle 100 at the intersection of roads R1 and R2.

[0059] Figure 2B This is an explanatory diagram showing an example of what happens immediately after a vehicle collision at speed 100.

[0060] As described above, when another vehicle 200 collides with the left side of vehicle 100 (this vehicle) (refer to...) Figure 2A At that moment, the impact caused changes in the position and orientation of vehicle 100 and other vehicles 200. Figure 2B In the example, the impact received from other vehicles 200 and the steering wheel 3 (refer to) Figure 1 As operated, vehicle 100 moves diagonally forward in a manner that moves towards the right lane of road R1.

[0061] exist Figure 2B In the example, the accelerator pedal 1 is pressed immediately after the impact (see reference). Figure 1 Therefore, the vehicle's speed of 100 is higher than the speed at which the collision occurred (refer to...). Figure 2A The speed increases. Furthermore, in the right lane of road R1, another vehicle 300 is traveling behind vehicle 100. Although described in detail later, in the first embodiment, the higher the speed of vehicle 100 at the time of collision, the smaller the braking torque of the automatic braking control. Therefore, it is possible to prevent rear-end collisions (secondary collisions) with other vehicles like vehicle 300 after the collision of vehicle 100, and even in the event of a rear-end collision, damage can be mitigated.

[0062] Figure 3 This is an explanatory diagram showing the change in wheel speed over the time including the time of the collision.

[0063] also, Figure 3 The horizontal axis represents time, and the vertical axis represents wheel speed. Additionally, in Figure 3 After the collision of vehicle 100 occurs at time t1, braking based on automatic braking control begins at time t4. Incidentally, the time from time t1 to time t4 is the time required for the judgment and processing of the collision and the communication between the equipment of vehicle 100, which is actually a very short time.

[0064] For example, such as Figure 2A As shown, in the event of a collision between another vehicle 200 and the left front side of vehicle 100, sometimes the wheel speed sensor 8 of the left front wheel of vehicle 100 (see reference) Figure 1 It may break or malfunction. Figure 3 In the example, taking the moment t1 when the collision occurs as the boundary, the wheel speed v of the left front wheel... FL The detected value dropped sharply from value v1 to zero (single-dot dash). This is due to the wheel speed sensor 8 on the left front wheel (refer to...). Figure 1 The vehicle malfunctioned. In fact, although the vehicle moved 100 degrees after the collision (see reference...). Figure 2B However, due to a malfunction in the wheel speed sensor 8 of the left front wheel, the wheel speed v... FLThe detected value is output as zero, which deviates from the actual speed of the vehicle (100).

[0065] In addition, such as Figure 2A As shown, in the event of a collision between the front left side of vehicle 100 and another vehicle 200, in most cases, the impact causes the left rear wheel to reach a speed of v. RL Temporarily reduced. Figure 3 In the example, during the period from time t1 to time t2 immediately after the collision, the wheel speed v of the left rear wheel is... RL The value v1 rapidly decreases to v2 (dashed line). Additionally, during the period from time t2 to time t3, the wheel speed v of the left rear wheel... RL It rises, and after time t3, becomes the wheel speed v of the right front wheel. FR and the wheel speed v of the right rear wheel RR The values ​​are roughly the same (dashed line).

[0066] From time t1 to time t4 after the collision, no automatic braking control was executed, but the actual speed of vehicle 100 decreased due to the impact force accompanying the collision. Furthermore, after time t4, automatic braking control was executed, and the speed of vehicle 100 decreased at a large angle. Thus, by executing automatic braking control immediately after the collision of vehicle 100, the impact force on the occupants was mitigated. Figure 3 In the example, braking based on automatic braking control begins at time t4, thus, in addition to the wheel speed v of the right front wheel... FR (Solid line) and the wheel speed v of the right rear wheel RR Outside the solid line, the wheel speed v of the left rear wheel RL (The dashed line) also decreases with a large slope.

[0067] exist Figure 3 In the example, due to the wheel speed sensors 8 of the right front wheel, right rear wheel, and left rear wheel (refer to...) Figure 1 There was no malfunction, so its wheel speed v FR v RR v RL (However, regarding wheel speed v) RL (The detected value after time t3) changes in a manner corresponding to the actual vehicle speed. Additionally, Figure 3 The wheel speed v shown s This refers to the wheel speed used by automatic braking control. Although detailed later, the wheel speed v at the time of the collision... FR v RR v RL v FL Appropriately select the wheel speed v for automatic braking control s .

[0068] Figure 4This is a flowchart illustrating the processing of the vehicle control unit 10 (see relevant documentation). Figure 1 ).

[0069] In addition, when Figure 4 At the “start”, the collision of vehicle 100 had not yet occurred, and vehicle 100 was driving normally.

[0070] Figure 4 In step S101, the vehicle control device 10 determines whether a collision of the vehicle 100 has been detected. That is, the vehicle control device 10 determines whether a collision detection signal Sd has been input from the collision detection sensor 9. If no collision of the vehicle 100 is detected in step S101 (S101: No), the vehicle control device 10 repeats the process of step S101. On the other hand, if a collision of the vehicle 100 is detected in step S101 (S101: Yes), the process of the vehicle control device 10 proceeds to step S102.

[0071] In step S102, the vehicle control unit 10 determines whether braking based on the operation of the brake pedal 2 occurred during a collision. That is, when a collision detection signal Sd is input from the collision detection sensor 9, the vehicle control unit 10 determines whether an ON signal is input from the brake switch 2a as a brake switch signal Sb. As described above, when the brake pedal 2 is depressed, an ON signal is input, for example, as a brake switch signal Sb sent from the brake switch 2a to the vehicle control unit 10. If, in step S102, braking based on the operation of the brake pedal 2 occurred during a collision (S102: Yes), the processing of the vehicle control unit 10 proceeds to step S103.

[0072] In step S103, the vehicle control unit 10 calculates the vehicle speed at the time of collision based on the highest wheel speed using the speed calculation unit 12. Here, "vehicle speed at the time of collision" refers to, for example, the vehicle speed at the moment when the collision detection signal Sd is input from the collision detection sensor 9 to the vehicle control unit 10. Alternatively, the vehicle speed at the moment when the airbag deployment signal (not shown) is output from the vehicle control unit 10 to the inflator (not shown) can also be used as "vehicle speed at the time of collision". In summary, the moment when a collision signal (e.g., the collision detection signal) is input to the vehicle control unit 10, or the moment when a collision-related signal (e.g., the airbag deployment signal) is output from the vehicle control unit 10, is defined as the "time of collision" of the vehicle 100.

[0073] Furthermore, if the brake pedal 2 is depressed during a collision (S102: Yes), the vehicle speed tends to decrease immediately after the collision. Therefore, in order to prevent the braking force of the automatic braking control from becoming too large, and in order to prevent wheel lock-up, the vehicle control device 10 calculates the vehicle speed at the time of the collision based on the highest wheel speed (S103).

[0074] Here, wheel lock-up refers to the phenomenon where, during the movement of vehicle 100 (both during travel and immediately following a collision), the rotation of at least one of multiple wheels stops (or nearly stops). By performing the process in step S103, excessive braking force based on a vehicle speed lower than the actual speed is prevented, thereby suppressing wheel lock-up. As a result, it is possible to prevent vehicle 100 from being rear-ended by subsequent vehicles after a collision.

[0075] Additionally, for example, if the vehicle tilts 100 degrees due to the impact of a collision, and the brake pedal 2 is applied when the specified wheel temporarily leaves the road surface, braking force may be applied to the wheel, potentially causing wheel lock-up. Regarding the locked wheel, since the detection value of the wheel speed sensor 8 is approximately zero, it deviates from the actual vehicle speed.

[0076] In contrast, the vehicle control device 10 calculates the vehicle speed at the time of collision based on the highest wheel speed (S103), and as the vehicle speed obtained based on the wheel speed, it can calculate a value that is approximately equal to the actual vehicle speed at the time of collision. Furthermore, it is almost impossible for all four wheels of the vehicle 100 to lock up. In addition, in most cases, the wheel speed of at least one of the four wheels becomes a value corresponding to the actual vehicle speed.

[0077] Furthermore, in step S103, the speed calculation unit 12 can directly convert the highest wheel speed into the vehicle speed at the time of the collision. Alternatively, for example, the speed calculation unit 12 can convert the value obtained by multiplying the highest wheel speed by a predetermined correction factor into the vehicle speed at the time of the collision.

[0078] In addition, in step S102, if there is no braking based on the operation of the brake pedal 2 at the time of the collision (S102: No), the processing of the vehicle control device 10 proceeds to step S104.

[0079] In step S104, the vehicle control device 10 calculates the vehicle speed at the time of collision based on the second lowest wheel speed using the speed calculation unit 12. For example, if the brake pedal 2 is not engaged at the time of collision (S102: No), the vehicle 100 may violently collide with an object (other vehicles, etc.), causing at least one wheel to momentarily lift off the ground and spin freely. Additionally, on low-μ roads such as snow-covered or icy roads, the wheels may slip at the time of collision. Therefore, if the brake pedal 2 is not engaged at the time of collision (S102: No), the vehicle control device 10 does not reflect the wheel speed at the time of collision (the wheel speed higher than the second lowest in the order from low to high) in the vehicle speed calculation.

[0080] Additionally, if the vehicle 100 experiences a violent collision without the brake pedal 2 being applied, the wheel speed sensor 8 near the point of impact may sometimes be damaged or malfunction. In this case, the output value of the wheel speed sensor 8 will be zero, deviating from the actual vehicle speed at the time of the collision. For example, in Figure 3 In the example, after the collision occurs at time t1, the wheel speed sensor 8 of the left front wheel malfunctions, and the wheel speed v... FL The speed becomes zero. Therefore, if the brake pedal 2 is not depressed at the time of the collision (S102: No), the vehicle control device 10 does not reflect the wheel speed with the lowest wheel speed at the time of the collision in the calculation of the vehicle speed.

[0081] In this way, the vehicle control device 10 calculates the vehicle speed at the time of collision based on the second lowest wheel speed detected (S104), thereby improving the accuracy of vehicle speed detection at the time of collision and generating a larger braking force through subsequent automatic braking control (S105). Therefore, even if the vehicle 100 collides on a low-μ road that is prone to slipping, such as a snowy road or an icy road, insufficient braking force of the automatic braking control can be suppressed.

[0082] Furthermore, in step S104, the speed calculation unit 12 can directly convert the second lowest wheel speed into the vehicle speed at the time of the collision. Alternatively, for example, the speed calculation unit 12 can also convert the value obtained by multiplying the second lowest wheel speed by a predetermined correction factor into the vehicle speed at the time of the collision.

[0083] In progress Figure 4 After the processing in step S103 or S104, the processing of the vehicle control device 10 proceeds to step S105. In step S105, the vehicle control device 10 performs automatic braking control based on the vehicle speed at the time of the collision via the driver support control unit 14. For example, the vehicle control device 10 performs automatic braking control in a manner that the higher the vehicle speed at the time of the collision, the lower the deceleration of the vehicle 100. As a result, rear-end collisions between following vehicles and the vehicle 100 after the collision can be prevented. Figure 2B In the example, vehicle 100, which collided with other vehicle 200, was oriented towards the right lane of road R1, but by appropriately limiting the braking force of the automatic braking control, it was able to suppress a rear-end collision from other vehicle 300, which was a following vehicle. After performing the processing in step S105, the vehicle control device 10 ended a series of processes (end).

[0084] Figure 5 This is a timing diagram of the automatic braking control during a vehicle collision (also refer to...). Figure 1 ).

[0085] also, Figure 5 The horizontal axis represents time. Additionally, Figure 5The vertical axis, from the top of the paper, consists of the following parameters in sequence: ON / OFF of automatic braking control, ON / OFF of acceleration suppression control, wheel speed, opening degree (depressing amount) of accelerator pedal 1, braking torque required for deceleration, and brake hydraulic pressure. Figure 5 In the example, automatic braking control begins at time t1 when the collision occurs and is then released at time t4.

[0086] Figure 5 Acceleration suppression control refers to the control that prevents the opening (deposition) of the accelerator pedal 1 from being reflected in the driving force (or reduces the degree of reflection) when the driver does not press the accelerator pedal 1. Figure 5 In the example, acceleration suppression control is performed during the moments t2 to t3 immediately following the collision t1, so that even if the accelerator pedal 1 is pressed during this period (see also...). Figure 5 Even with the "opening of the accelerator pedal", the vehicle hardly accelerates at 100 km / h.

[0087] about Figure 5 The wheel speed sensor 8 on the left front wheel malfunctioned due to a collision, indicating a wheel speed v. FL The time t1 at the moment of collision becomes zero. Additionally, the wheel speed v of the left rear wheel... RL The impact caused a temporary sudden decrease followed by an increase in speed, then, along with the remaining right front wheel's wheel speed v. FR and the wheel speed v of the right rear wheel RR The same changes.

[0088] also, Figure 5 In the example, at the moment of the collision (time t1), the highest wheel speed is v1. Therefore, when brake pedal 2 is depressed at the moment of the collision ( Figure 4 S102: Yes, as the wheel speed v for automatic braking control s The highest wheel speed value, v1, is used. Furthermore, the vehicle speed at the time of the collision is calculated based on this value v1 (S103). Figure 5 In the example, at the time of the collision (time t1), the second lowest wheel speed from low to high is also value v1. Therefore, in the case where the brake pedal 2 was not depressed at the time of the collision ( Figure 4 S102: No), wheel speed v for automatic braking control s The second lowest wheel speed value, v1, is used.

[0089] Figure 5 The deceleration requirement braking torque shown is the command value for the braking torque of the braking device 22. Figure 5In the example, to rapidly decelerate immediately after a collision, at time t2, the deceleration requirement braking torque based on automatic braking control increases from zero to a predetermined value N1 in a stepped manner. Furthermore, from time t2 immediately after the collision until time t4 when the automatic braking control is OFF, a fixed value N1 is output as the deceleration requirement braking torque; then, as time passes, the deceleration requirement braking torque decreases until it becomes zero.

[0090] Furthermore, when automatic braking control is performed while the brake pedal 2 is depressed, the vehicle control device 10 may, for example, change the brake hydraulic pressure based on the specified deceleration requirement braking torque, regardless of the opening of the brake pedal 2.

[0091] Furthermore, the driver support control unit 14 of the vehicle control device 10 is preferably configured such that the higher the vehicle speed at the time of collision calculated by the speed calculation unit 12, the smaller the deceleration requirement braking torque (braking torque) in the automatic braking control. That is, the driver support control unit 14 is preferably configured such that the higher the vehicle speed at the time of collision, the lower the deceleration of the vehicle 100 after the collision. Thus, as described above, it is possible to suppress the application of excessive braking force immediately after the collision of the vehicle 100, thereby suppressing rear-end collisions from following vehicles.

[0092] Figure 5 The brake hydraulic fluid shown is the actual hydraulic fluid (brake hydraulic fluid) generated by the hydraulic cylinder (not shown) of the braking device 22. As described above, since the deceleration-required braking torque rises from zero to a value N1 in a stepped manner at time t2, the brake hydraulic fluid also rises at a steep angle. Then, based on the value of the deceleration-required braking torque, the brake hydraulic fluid of value P1 operates during the period from time t2 to t4. Furthermore, after time t4, as time passes, the brake hydraulic fluid decreases, becoming zero at time t6.

[0093] <Effect>

[0094] The vehicle control device 10 of the first embodiment is configured as described above. Next, the functions and effects obtained based on the processing of the vehicle control device 10 will be explained.

[0095] like Figures 1-5 As shown, the vehicle control device 10 includes: a speed calculation unit 12 that calculates the vehicle speed at the time of collision when a collision is detected by the collision detection sensor 9; and a driver support control unit 14 that performs automatic braking control based on the vehicle speed at the time of collision calculated by the speed calculation unit 12. The speed calculation unit 12 automatically applies the brake pedal 2 when the vehicle 100 is involved in a collision. Figure 4 (S101: Yes, S102: Yes), the vehicle speed at the time of collision is calculated based on the highest detection value among the detection values ​​of the wheel speed sensors 8 of each of the multiple wheels (S103).

[0096] With this configuration, even if the brake pedal 2 is depressed during a collision, wheel lock-up can be prevented. Therefore, preventing the vehicle 100 from being rear-ended by subsequent vehicles after a collision improves the safety of the vehicle 100 during a collision.

[0097] In addition, such as Figure 1 , Figure 4 As shown, preferably, the speed calculation unit 12 operates when the brake pedal 2 is not depressed during the collision of the vehicle 100. Figure 4 (S101: Yes, S102: No), the vehicle speed at the time of the collision is calculated based on the second lowest detection value among the detection values ​​of the wheel speed sensors 8 of each of the multiple wheels (S104).

[0098] Based on this configuration, even if the wheel speed sensor 8 malfunctions due to a collision with vehicle 100, the vehicle speed at the time of the collision can be calculated with high accuracy, and appropriate automatic braking control can be performed. Furthermore, even in the event of a collision with vehicle 100 on slippery, low-μ roads such as snow-covered or icy roads, insufficient braking force in the automatic braking control can be suppressed.

[0099] In addition, preferably, Figure 1 The driving support control unit 14 shown performs automatic braking control in a manner that the higher the vehicle speed at the time of collision, the lower the deceleration of the vehicle 100 after the collision.

[0100] Based on this configuration, it is possible to suppress secondary damage to the vehicle 100 after a collision caused by a rear-end collision with a vehicle following behind.

[0101] Implementation Method 2

[0102] The second embodiment differs from the first embodiment in that it performs automatic braking control based on the vehicle speed prior to the collision with vehicle 100, compared to a predetermined time prior. Furthermore, other components (such as the configuration of vehicle 100) are described in detail below. Figure 1 The same applies as in the first embodiment. Therefore, the parts that differ from the first embodiment will be described, and repeated parts will be omitted.

[0103] Figure 6 This is a flowchart illustrating the processing of the vehicle control device 10 according to the second embodiment (see also the flowchart). Figure 1 ).

[0104] In addition, when Figure 6 At the “start”, no collision occurred with vehicle 100, and vehicle 100 was driving normally.

[0105] Figure 6In step S201, the vehicle control device 10 determines whether a collision of the vehicle 100 has been detected. If no collision of the vehicle 100 is detected in step S201 (S201: No), the vehicle control device 10 repeats the process of step S201. Alternatively, if a collision of the vehicle 100 is detected in step S201 (S201: Yes), the process of the vehicle control device 10 proceeds to step S202.

[0106] In step S202, the vehicle control device 10 reads the vehicle speed from the storage unit 11 before the collision, relative to a predetermined time, via the speed calculation unit 12. This predetermined time is preset and stored in the storage unit 11, enabling the vehicle 100 to obtain its speed immediately before the collision. Furthermore, immediately before the collision, the vehicle speed is calculated and stored in the storage unit 11, for example, based on the average value of the detection values ​​from the wheel speed sensors 8 of the right front wheel, left front wheel, right rear wheel, and left rear wheel.

[0107] Next, in step S203, the vehicle control device 10 sets the vehicle speed before a predetermined time before the collision as the vehicle speed at the time of the collision through the speed calculation unit 12. In this way, by using the vehicle speed before the predetermined time before the collision (immediately before the collision) as the vehicle speed at the time of the collision, appropriate subsequent automatic braking control can be performed even if the vehicle speed changes drastically before and after the collision.

[0108] Next, in step S204, the vehicle control device 10 performs automatic braking control based on the vehicle speed at the time of the collision. For example, the vehicle control device 10 performs automatic braking control in a manner that the higher the vehicle speed at the time of the collision, the lower the deceleration of the vehicle 100. As a result, it is possible to prevent the vehicle 100 from being rear-ended by subsequent vehicles after the collision.

[0109] <Effect>

[0110] The vehicle control device 10 of the second embodiment is basically configured as described above. Next, the functions and effects obtained based on the processing of the vehicle control device 10 will be explained.

[0111] like Figure 1 , Figure 6 As shown, the vehicle control device 10 includes: a speed calculation unit 12 that calculates the vehicle speed at the time of collision when a collision is detected by the collision detection sensor 9; and a driver support control unit 14 that performs automatic braking control based on the vehicle speed at the time of collision calculated by the speed calculation unit 12. The speed calculation unit 12 uses the vehicle speed before the collision, compared to a predetermined time prior, as the vehicle speed at the time of collision. Figure 6 S201: Yes, S202, S203).

[0112] Based on this configuration, even if the vehicle speed changes drastically before and after a collision, appropriate subsequent automatic braking control can be performed.

[0113] Variations

[0114] The vehicle control device 10 of the present invention has been described above through various embodiments (see above). Figure 1 However, it is not limited to these records and can be modified in various ways.

[0115] For example, the first embodiment describes the situation where the brake pedal 2 was not depressed during the collision of vehicle 100 ( Figure 4 (S101: Yes, S102: No), the speed calculation unit 12 calculates the vehicle speed at the time of the collision based on the detection value of the second lowest wheel speed (S104), but is not limited to this. For example, if the vehicle 100 has multiple wheels including left and right front wheels and left and right rear wheels, the speed calculation unit 12 may also calculate the vehicle speed at the time of the collision based on the lower of the higher detection value of the wheel speed sensor 8 in the left and right front wheels and the higher detection value of the wheel speed sensor 8 in the left and right rear wheels, when the brake pedal 2 is not depressed at the time of the collision.

[0116] With this configuration, even if the wheel speed sensor 8 malfunctions during a collision, the detected value can be prevented from being reflected in the vehicle speed calculation. Furthermore, even in the event of a collision on low-μ roads such as snow-covered or icy roads where the vehicle 100 is prone to slipping, insufficient braking force in the automatic braking control can be suppressed.

[0117] Furthermore, while each embodiment describes automatic braking control based on the vehicle speed at the time of the collision, it is not limited to this. For example, automatic braking control could also be based on the vehicle speed at the start of braking performed by automatic braking control (or, although after the collision, immediately before the start of braking). This approach can achieve the same effects as in each embodiment.

[0118] Furthermore, these embodiments can also be applied to vehicles that perform so-called autonomous driving. Here, autonomous driving refers to driving a vehicle by the vehicle control device 10 performing at least one of acceleration, deceleration, or steering, without relying on the driving operations of the occupants. In addition, in autonomous driving vehicles, manual driving based on the occupants is also possible. For example, during the execution of autonomous driving, the occupants can switch from autonomous driving to manual driving by performing prescribed operations on the driving control elements.

[0119] Furthermore, each embodiment can also be applied to vehicles that, while in motion, detect objects (other vehicles, guardrails, utility poles, etc.) in at least one of the following directions: forward, side, or rear. If a high probability of a collision is determined, the vehicle control device 10 provides prescribed driving assistance (such as braking without driver input) to avoid the collision. Even when such driving assistance is provided, the possibility of a collision still exists, but by applying each embodiment, secondary damage after a collision can be avoided or mitigated. For example, the vehicle control device 10 may provide prescribed driving assistance when the probability of a collision is high, and perform automatic braking control in the event of an actual collision.

[0120] Furthermore, in addition to four-wheeled vehicles, each embodiment can also be applied to two-wheeled and three-wheeled vehicles. Alternatively, programs for causing a computer to execute the methods described in each embodiment can be stored in a memory, hard disk, IC (Integrated Circuit) card, or other recording media.

Claims

1. A vehicle control device, characterized in that, have: A speed calculation unit that calculates the vehicle speed at the time of collision when a vehicle collision is detected by a collision detection sensor; and A driver support control unit that performs automatic braking control based on the vehicle speed at the time of collision calculated by the speed calculation unit. When the brake pedal is depressed at the time of a collision, the speed calculation unit calculates the vehicle speed at the time of the collision based on the highest detection value from the wheel speed sensors of the left and right front wheels and the left and right rear wheels. The speed calculation unit calculates the vehicle speed at the time of the collision based on the second lowest detection value among the detection values ​​of the wheel speed sensors of the left and right front wheels and the left and right rear wheels, when the brake pedal is not depressed at the time of the collision.

2. The vehicle control device according to claim 1, characterized in that, The driver support control unit performs automatic braking control in such a way that the higher the vehicle speed at the time of collision, the lower the deceleration of the vehicle after the collision.

3. A vehicle control device, characterized in that, have: A speed calculation unit that calculates the vehicle speed at the time of collision when a vehicle collision is detected by a collision detection sensor; and A driver support control unit that performs automatic braking control based on the vehicle speed at the time of collision calculated by the speed calculation unit. When the brake pedal is depressed during a collision, the speed calculation unit calculates the vehicle speed at the time of the collision based on the highest detection value among the detection values ​​from the wheel speed sensors of each of the multiple wheels. The plurality of wheels includes left and right front wheels and left and right rear wheels. When the brake pedal is not depressed at the time of the vehicle collision, the speed calculation unit calculates the vehicle speed at the time of the collision based on the lower of the higher of the wheel speed sensor values ​​detected in the left and right front wheels and the higher of the wheel speed sensor values ​​detected in the left and right rear wheels, provided that the vehicle speed is not depressable at the time of the collision.

4. The vehicle control device according to claim 3, characterized in that, The driver support control unit performs automatic braking control in such a way that the higher the vehicle speed at the time of collision, the lower the deceleration of the vehicle after the collision.

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