Vehicle control device

Abstract

To provide a vehicle control device, which can be switched into an optimal control mode on the basis of vehicle characteristics depending on a situation of a road surface as one example, so as to reduce burdens on a user.SOLUTION: A vehicle control device is provided with: an analyzing part that analyzes a situation of a road surface from a photographed image photographed by a photographing device that photographs a road surface in a travelling direction of a vehicle; a switching part that switches a control mode of showing a level of control relating to travelling of the vehicle, on the basis of the situation of the road surface and vehicle characteristics based on sensed information by an on-vehicle sensor; and a control part that controls the vehicle in the switched control mode.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] An embodiment of the present invention relates to a vehicle control device. [Background technology]

[0002] In device control for ride comfort, handling stability, etc. in a vehicle, it has been conventional to realize switching between control modes such as comfort, normal, and sport by manual operation such as switch operation by a user such as a driver or passenger. Furthermore, in the conventional technology, various devices for ride comfort, handling stability, etc. are controlled to optimize vehicle characteristics based on detection values ​​of various on-board sensors such as a vertical acceleration sensor and a vehicle height sensor while the vehicle is traveling. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-147114 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in such conventional technology, the control mode is switched manually by the user based on visual and sensory judgment, which makes the operation complicated for the user and places a burden on both parties. [Means for solving the problem]

[0005] The vehicle control device of the embodiment includes an analysis unit that analyzes road surface conditions from an image captured by an imaging device that captures an image of the road surface in the traveling direction of the vehicle, a switching unit that switches a control mode indicating a level of control related to the traveling of the vehicle based on the road surface conditions and vehicle characteristics based on detection information by an on-board sensor, and a control unit that controls the vehicle in the switched control mode. a learning unit that inputs and learns the road surface condition and the detection information while the vehicle is traveling, and changes a predetermined control mode to the vehicle characteristics based on the road surface condition and the detection information, and the switching unit switches to the changed control mode.This configuration, for example, allows switching to an optimal control mode based on vehicle characteristics in response to road surface conditions, thereby reducing the burden on users. Furthermore, this configuration also allows switching to an optimal control mode based on vehicle characteristics in response to road surface undulations, even when there is no driver and passengers cannot grasp the road surface conditions, such as in the case of an autonomous vehicle, which is convenient for passengers. Furthermore, with this configuration, as an example, the threshold for switching control modes can be dynamically changed while the vehicle is traveling, allowing the vehicle to switch to the optimal control mode depending on the road conditions, further reducing the burden on the user.

[0006] In addition, in the vehicle control device of the embodiment, the vehicle characteristics include heave characteristics, roll characteristics, or pitch characteristics of the vehicle based on vertical acceleration, lateral acceleration, or longitudinal acceleration detected by an acceleration sensor serving as the on-board sensor, or the vehicle height detected by a vehicle height sensor serving as the on-board sensor. With this configuration, for example, it is possible to switch to a more optimal control mode based on the heave, roll, or pitch characteristics of the vehicle depending on road surface conditions, thereby further reducing the burden on the user.

[0007] In addition, in the vehicle control device of the embodiment, the analysis unit determines the road surface undulation state as one of rough, normal, and flat as the road surface condition, and the switching unit switches the control mode between a plurality of modes with different levels of control intensity based on the road surface undulation state and the vehicle characteristics. With this configuration, for example, it is possible to switch to an optimal control mode based on the vehicle characteristics in accordance with the road surface undulation state, thereby further reducing the burden on the user.

[0008] In addition, in the vehicle control device of the embodiment, the control mode corresponding to the road surface condition and the vehicle characteristics is predetermined, and the switching unit switches to the control mode determined corresponding to the road surface condition and the vehicle characteristics. With this configuration, for example, if the vehicle characteristics are determined in advance before shipping, there is no need to install an on-board sensor for determining the vehicle characteristics in the shipped vehicle, thereby reducing the installation space in the vehicle and the vehicle manufacturing costs.

[0010] In addition, in the vehicle control device of the embodiment, the switching unit calculates a frequency of the road surface undulation state from the road surface condition and the vehicle speed, and switches the control mode based on the calculated frequency and the vehicle characteristics. With this configuration, for example, it is possible to switch to a more optimal control mode based on the vehicle characteristics in accordance with the road surface undulation state, thereby further reducing the burden on the user.

[0011] In addition, in the vehicle control device of the embodiment, the switching unit further switches the control mode based on the road surface condition and the vehicle characteristics based on the sound generated by the road surface condition. With this configuration, for example, it is possible to recognize the road surface condition with higher accuracy, so it is possible to switch to a more optimal control mode based on the vehicle characteristics in accordance with the road surface condition, and it is possible to more accurately reduce the burden on the user.

[0012] In addition, in the vehicle control device of the embodiment, the control unit includes a damping force control unit for a suspension of the vehicle, and the switching unit further switches the control mode based on the road surface condition and the vehicle characteristics based on the acceleration of a shock absorber rod of the suspension or the sprung acceleration or unsprung acceleration of the suspension. With this configuration, for example, it is possible to recognize the road surface condition with higher accuracy, so that it is possible to switch to a more optimal control mode based on the vehicle characteristics in accordance with the road surface condition, and it is possible to more accurately reduce the burden on the user. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is an exemplary perspective view showing a state in which a part of a vehicle interior according to a first embodiment is seen through. [Figure 2] FIG. 2 is an exemplary plan view of the vehicle according to the first embodiment. [Figure 3] FIG. 3 is an exemplary block diagram of the configuration of a vehicle control system included in the vehicle according to the first embodiment. [Figure 4]FIG. 4 is a diagram illustrating an example of a functional configuration of an ECU included in the vehicle according to the first embodiment. [Figure 5] FIG. 5 is an explanatory diagram showing the state of each control level set in the control mode in the first embodiment. [Figure 6] FIG. 6 is a flowchart illustrating an example of a procedure for vehicle control processing by the vehicle control system according to the first embodiment. [Figure 7] FIG. 7 is an exemplary block diagram of a configuration of a vehicle control system included in a vehicle according to the second embodiment. [Figure 8] FIG. 8 is a diagram illustrating an example of a functional configuration of an ECU included in a vehicle according to the second embodiment. [Figure 9] FIG. 9 is a flowchart illustrating an example of a procedure for vehicle control processing by the vehicle control system according to the second embodiment. [Figure 10] FIG. 10 is a flowchart illustrating an example of a procedure for vehicle control processing by the vehicle control system according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0014] Exemplary embodiments of the present invention are disclosed below. The configurations of the embodiments described below, as well as the actions, results, and advantages brought about by the configurations, are merely examples. The present invention can be realized by configurations other than those disclosed in the following embodiments, and it is possible to obtain at least one of the various advantages based on the basic configurations and derivative advantages.

[0015] (First embodiment) The vehicle 1 of this embodiment may be, for example, an automobile using an internal combustion engine (not shown) as a drive source, i.e., an internal combustion engine automobile, or an automobile using an electric motor (not shown) as a drive source, i.e., an electric automobile or a fuel cell automobile, or a hybrid automobile using both of these as a drive source, or an automobile equipped with another drive source. The vehicle 1 may be equipped with various transmissions and various devices, such as systems and components, required to drive the internal combustion engine or electric motor. The type, number, layout, etc. of the devices related to driving the wheels 3 of the vehicle 1 may be variously configured.

[0016] Fig. 1 is an exemplary perspective view showing a state in which a part of a cabin of a vehicle according to a first embodiment is seen through. Fig. 2 is an exemplary plan view of the vehicle according to the first embodiment. Fig. 3 is an exemplary block diagram of a configuration of a vehicle control system included in the vehicle according to the first embodiment.

[0017] First, an example of the configuration of a vehicle 1 according to this embodiment will be described with reference to FIGS. 1, the vehicle body 2 forms a cabin 2a in which a passenger (not shown) rides. Inside the cabin 2a, a steering unit 4, an acceleration operation unit 5, a braking operation unit 6, a gear change operation unit 7, etc. are provided facing a seat 2b for a driver as a passenger.

[0018] The steering unit 4 is, for example, a steering wheel protruding from the dashboard 24. The acceleration operation unit 5 is, for example, an accelerator pedal located under the driver's feet. The braking operation unit 6 is, for example, a brake pedal located under the driver's feet. The gear change operation unit 7 is, for example, a shift lever protruding from the center console. However, the steering unit 4, acceleration operation unit 5, braking operation unit 6, gear change operation unit 7, etc. are not limited to these.

[0019] A display device 8 serving as a display output unit and an audio output device 9 serving as an audio output unit are provided in the vehicle interior 2a. The display device 8 is, for example, an LCD (Liquid Crystal Display) or an OLED (Organic Electroluminescent Display). The audio output device 9 is, for example, a speaker. The display device 8 is covered with a transparent operation input unit 10 such as a touch panel. The occupant can visually recognize an image displayed on the display screen of the display device 8 via the operation input unit 10. The occupant can also perform operation input by touching, pressing, or moving the operation input unit 10 with a finger or the like at a position corresponding to the image displayed on the display screen of the display device 8.

[0020] The display device 8, audio output device 9, operation input unit 10, etc. are provided in a monitor device 11, for example, located in the center of the dashboard 24 in the vehicle width direction, i.e., the left-right direction. The monitor device 11 may have an operation input unit (not shown), such as a switch, a dial, a joystick, or a push button. An audio output device (not shown) may be provided in another position in the vehicle compartment 2a different from the monitor device 11, and audio may be output from the audio output device 9 of the monitor device 11 and the other audio output device. The monitor device 11 may also be used as, for example, a navigation system or an audio system. A display device 12 separate from the display device 8 is also provided in the vehicle compartment 2a.

[0021] 1 and 2, the vehicle 1 is, for example, a four-wheeled vehicle having two front wheels 3F (left and right) and two rear wheels 3R ​​(left and right). All four wheels 3 can be configured to be steerable. As shown in FIG. 3, the vehicle 1 has a steering system 13 that steers at least two wheels 3.

[0022] The steering system 13 has an actuator 13a and a torque sensor 13b. The steering system 13 is electrically controlled by an ECU 14 (Electronic Control Unit) or the like to operate the actuator 13a. The steering system 13 is, for example, an electric power steering system or a steer-by-wire (SBW) system. The steering system 13 supplements the steering force by applying torque, i.e., assist torque, to the steering unit 4 using the actuator 13a, and steers the wheels 3 using the actuator 13a. In this case, the actuator 13a may steer one wheel 3 or multiple wheels 3. Furthermore, the torque sensor 13b detects, for example, the torque applied to the steering unit 4 by the driver.

[0023] 2, the vehicle body 2 is provided with a plurality of imaging units 15, for example, four imaging units 15a to 15d. The imaging units 15 are, for example, digital cameras incorporating imaging elements such as a CCD (Charge Coupled Device) or a CIS (CMOS Image Sensor). The imaging units 15 can output video data at a predetermined frame rate. Each imaging unit 15 has a wide-angle lens or a fisheye lens and can capture images in a horizontal range of, for example, 140° to 190°. The optical axis of the imaging unit 15 is set to point diagonally downward. Therefore, the imaging units 15 sequentially capture images of the external environment around the vehicle body 2, including road surfaces on which the vehicle 1 can move and areas in which the vehicle 1 can be parked, and output the captured image data.

[0024] The imaging unit 15a is located, for example, at the rear end 2e of the vehicle body 2 and is provided on a wall below the rear trunk door 2h. The imaging unit 15b is located, for example, at the right end 2f of the vehicle body 2 and is provided on the right door mirror 2g. The imaging unit 15c is located, for example, at the front end 2c of the vehicle body 2, i.e., the front side in the vehicle longitudinal direction, and is provided on the front bumper or the like. The imaging unit 15d is located, for example, at the left end 2d of the vehicle body 2, i.e., the left side in the vehicle width direction, and is provided on the door mirror 2g, which is a left protrusion. The ECU 14 performs arithmetic processing and image processing based on image data obtained by the multiple imaging units 15, and can generate images with a wider field of view or generate a virtual overhead image of the vehicle 1 viewed from above. Note that the overhead image can also be referred to as a planar image.

[0025] In this embodiment, an image of the road surface ahead, which is the traveling direction of the vehicle 1, is captured by the imaging unit 15c as an imaging device provided on the front side of the vehicle body 2. When the vehicle 1 moves backward, the direction behind the vehicle 1 becomes the traveling direction, and the imaging unit 15a may be configured to capture an image of the road surface behind the vehicle 1.

[0026] 1 and 2, the vehicle body 2 is provided with a plurality of distance measuring units 16, 17, for example, four distance measuring units 16a to 16d and eight distance measuring units 17a to 17h. The distance measuring units 16, 17 are, for example, sonars that emit ultrasonic waves and capture the reflected waves. Sonars can also be called sonar sensors or ultrasonic detectors. Based on the detection results of the distance measuring units 16, 17, the ECU 14 can measure the presence or absence of objects, such as obstacles, positioned around the vehicle 1 and the distance to the objects. In other words, the distance measuring units 16, 17 are examples of detection units that detect objects. Note that the distance measuring unit 17 can be used, for example, to detect objects at a relatively short distance, and the distance measuring unit 16 can be used, for example, to detect objects at a relatively long distance that are farther away than the distance measuring unit 17. Furthermore, the distance measuring unit 17 can be used to detect objects in front of and behind the vehicle 1, and the distance measuring unit 16 can be used to detect objects to the side of the vehicle 1, for example.

[0027] 3, in the vehicle control system 100, the ECU 14, the monitor device 11, the steering system 13, the distance measurement units 16 and 17, the brake system 18, the suspension system 30, the steering angle sensor 19, the accelerator sensor 20, the shift sensor 21, the wheel speed sensor 22, etc. are electrically connected via an in-vehicle network 23 serving as an electrical communication line. The in-vehicle network 23 is configured as, for example, a CAN (controller area network).

[0028] The ECU 14 can control the steering system 13, the brake system 18, etc. by sending control signals via the in-vehicle network 23. The ECU 14 can also receive, via the in-vehicle network 23, detection results from the torque sensor 13b, the brake sensor 18b, the steering angle sensor 19, the distance measurement unit 16, the distance measurement unit 17, the accelerator sensor 20, the shift sensor 21, the wheel speed sensor 22, etc., as well as operation signals from the operation input unit 10, etc.

[0029] The ECU 14 includes, for example, a CPU 14a (Central Processing Unit), a ROM (Read Only Memory) 14b, a RAM (Random Access Memory) 14c, a display control unit 14d, an audio control unit 14e, and an SSD (Solid State Drive, flash memory) 14f.

[0030] The CPU 14a can execute various types of arithmetic processing and control, such as image processing related to images displayed on the display devices 8 and 12, determination of the target position of the vehicle 1, calculation of the movement path of the vehicle 1, determination of the presence or absence of interference with an object, automatic control of the vehicle 1, cancellation of automatic control, damping control of the suspension system 30, spring constant switching control, steering control, stabilizer control, etc. The CPU 14a can read out programs installed and stored in a nonvolatile storage device such as the ROM 14b, and execute arithmetic processing in accordance with the programs.

[0031] The RAM 14c temporarily stores various data used in the calculations performed by the CPU 14a. The display control unit 14d mainly performs image processing using image data obtained by the imaging unit 15 and synthesis of image data displayed on the display device 8, among the calculations performed by the ECU 14. The audio control unit 14e mainly performs processing of audio data output by the audio output device 9, among the calculations performed by the ECU 14. The SSD 14f is a rewritable nonvolatile storage unit that can store data even when the power to the ECU 14 is turned off. The CPU 14a, ROM 14b, RAM 14c, etc. may be integrated in the same package. The ECU 14 may be configured to use another logic calculation processor, such as a DSP (Digital Signal Processor), a logic circuit, etc., instead of the CPU 14a. The SSD 14f may be replaced by an HDD (Hard Disk Drive), or the SSD 14f and HDD may be provided separately from the ECU 14.

[0032] The brake system 18 may be, for example, an anti-lock brake system (ABS) that prevents the brakes from locking, an electronic stability control (ESC) that prevents the vehicle 1 from skidding when cornering, an electric brake system that increases the braking force (performs brake assist), or a brake-by-wire (BBW). The brake system 18 applies braking force to the wheels 3 and thus the vehicle 1 via an actuator 18a. The brake system 18 can also detect signs of brake lock, freewheeling of the wheels 3, skidding, etc. from the rotational difference between the left and right wheels 3, and execute various controls. The brake sensor 18b is, for example, a sensor that detects the position of a movable part of the brake operating unit 6. The brake sensor 18b can detect the position of a brake pedal, which is a movable part. The brake sensor 18b includes a displacement sensor.

[0033] The steering angle sensor 19 is a sensor that detects the amount of steering of the steering unit 4, such as a steering wheel. The steering angle sensor 19 is configured using, for example, a Hall element. The ECU 14 acquires the amount of steering of the steering unit 4 by the driver, the amount of steering of each wheel 3 during automatic steering, etc. from the steering angle sensor 19 and performs various controls. The steering angle sensor 19 detects the rotation angle of a rotating part included in the steering unit 4.

[0034] The accelerator sensor 20 is, for example, a sensor that detects the position of a movable part of the acceleration operating unit 5. The accelerator sensor 20 can detect the position of an accelerator pedal as a movable part. The accelerator sensor 20 includes a displacement sensor.

[0035] The shift sensor 21 is, for example, a sensor that detects the position of a movable part of the gear shift operating device 7. The shift sensor 21 can detect the position of a movable part such as a lever, arm, or button. The shift sensor 21 may include a displacement sensor or may be configured as a switch.

[0036] The wheel speed sensor 22 is a sensor that detects the amount of rotation of the wheel 3 and the number of rotations per unit time. The wheel speed sensor 22 outputs the number of wheel speed pulses indicating the detected number of rotations as a sensor value. The wheel speed sensor 22 can be configured using, for example, a Hall element. The ECU 14 calculates the amount of movement of the vehicle 1 and the like based on the sensor value acquired from the wheel speed sensor 22 and executes various controls. Note that the wheel speed sensor 22 may be provided in the brake system 18. In this case, the ECU 14 acquires the detection result of the wheel speed sensor 22 via the brake system 18.

[0037] The suspension system 30 is disposed between the vehicle body 2 and the wheels 3 of the vehicle 1. The suspension system 30 includes a spring that absorbs vibrations of the vehicle 1 caused by impacts to the vehicle 1 from the road surface, and a variable damping damper that damps the vibrations of the spring and can change the damping force of the spring vibrations. In this embodiment, the suspension system 30 cooperates with the ECU 14 to control a damping force adjusting device such as a solenoid actuator to change the damping force of the variable damping damper. In this way, the suspension system 30 realizes an AVS (Adaptive Variable Suspension System) that damps vibrations of the vehicle body in the up-down, lateral, and longitudinal directions caused by impacts to the vehicle 1 from the road surface.

[0038] The configurations, arrangements, electrical connection forms, etc. of the various sensors and actuators described above are merely examples, and can be set (changed) in various ways.

[0039] Next, an example of the functional configuration of the ECU 14 included in the vehicle 1 according to the present embodiment will be described with reference to Fig. 4. Fig. 4 is a diagram illustrating an example of the functional configuration of the ECU 14 included in the vehicle according to the first embodiment.

[0040] 4, the ECU 14 according to this embodiment functions as a vehicle control device having at least an acquisition unit 141, an analysis unit 142, a switching unit 143, a control unit 140, and a storage unit 150. As shown in FIG. 4, the control unit 140 mainly includes a damping force control unit 144, a spring constant switching control unit 145, a steering control unit 146, and a stabilizer control unit 147.

[0041] Furthermore, the various functional modules such as the acquisition unit 141, analysis unit 142, switching unit 143, damping force control unit 144, spring constant switching control unit 145, steering control unit 146, and stabilizer control unit 147 are just examples, and each functional module may be integrated or subdivided as long as it can achieve similar functions.

[0042] The acquisition unit 141 acquires detection information from various sensors such as the wheel speed sensor 22 and the steering angle sensor 19. The acquisition unit 141 also acquires an image of the road surface in the traveling direction of the vehicle 1, which is captured by the imaging unit 15c.

[0043] The analysis unit 142 analyzes the road surface conditions from the captured image acquired by the acquisition unit 141. Specifically, the analysis unit 142 analyzes the captured image and determines the road surface condition, ie, the undulation state of the road surface, as either rough, normal, or flat.

[0044] The storage unit 150 corresponds to the SSD 14f, the ROM 14b, etc. The storage unit 150 stores vehicle characteristic information 151 in advance from the time of shipping of the vehicle 1.

[0045] The vehicle characteristic information 151 stores vehicle characteristics, which are characteristics of the vehicle 1, associated with the control mode as a threshold for switching the control mode. There are three control modes: comfort mode, normal mode, and sport mode. Details of the control modes will be described later.

[0046] Before shipping the vehicle 1, the vehicle 1 is equipped with on-board sensors, and the vehicle 1 is driven while the vehicle is running. The vehicle 1 is then equipped with on-board sensors, and the road undulation state is determined from images captured by the imaging unit 15c. The vibration frequency of the vehicle 1 is determined from the undulation information and the vehicle speed based on the wheel speed sensor 22. An appropriate control mode is associated with the undulation state, the vibration frequency, and the vehicle characteristics determined from the detection information of the on-board sensors. In this embodiment, for example, a vertical acceleration sensor, a lateral acceleration sensor, a longitudinal acceleration sensor, a vehicle height sensor, etc. are used as on-board sensors, and the vehicle characteristics are determined from the detection information of these sensors. The optimal control mode is associated with the range of the vehicle characteristics and stored in the storage unit 150 as the vehicle characteristics information 151. That is, the vehicle characteristics are registered in the vehicle characteristics information 151 as thresholds for switching the control mode.

[0047] The vehicle characteristics include heave characteristics such as the heave speed of the vehicle 1 based on the acceleration acting in the vertical direction of the vehicle 1 detected by the vertical acceleration sensor and the vehicle height detected by the vehicle height sensor, roll characteristics such as the roll speed of the vehicle 1 based on the acceleration acting in the width direction (lateral direction) of the vehicle 1 detected by the lateral acceleration sensor, and pitch characteristics such as the pitch speed and pitch rate of the vehicle 1 based on the acceleration acting in the longitudinal direction of the vehicle 1 detected by the longitudinal acceleration sensor.

[0048] In this embodiment, these on-board sensors are temporarily attached to the vehicle 1 before the vehicle 1 is shipped, but after the vehicle characteristics are determined, they are removed from the vehicle 1 before the vehicle 1 is shipped.

[0049] The switching unit 143 switches the control mode based on the road surface conditions analyzed by the analysis unit 142 and the vehicle characteristic information 151. Specifically, the switching unit 143 determines the vehicle speed of the vehicle 1 from the detection information of the wheel speed sensors 22 acquired by the acquisition unit 141. Then, the switching unit 143 calculates the vibration frequency of the vehicle 1 from the road surface conditions analyzed and determined by the analysis unit 142, i.e., the road surface undulation state (rough, normal, flat), and the vehicle speed. The switching unit 143 then switches the control mode by referring to the vibration frequency of the vehicle 1 and the vehicle characteristics as thresholds of the vehicle characteristic information 151 stored in advance in the storage unit 150.

[0050] Here, the control mode is a mode that indicates the level of control regarding the driving of the vehicle 1. The control level is the intensity of control, and the switching unit 143 switches the control mode between a plurality of modes with different intensity of control. In this embodiment, there are three control modes: comfort mode, normal mode, and sport mode. The normal mode is a mode with normal control intensity. The comfort mode is a mode with softer control intensity than the normal mode (i.e., softer). The sport mode is a mode with harder control intensity than the normal mode (i.e., harder). The normal mode corresponds to the first mode, the comfort mode corresponds to the second mode, and the sport mode corresponds to the third mode. Note that the number of control modes is not limited to these.

[0051] Specifically, the control mode is switched by the switching unit 143 under the control of the control unit 140 as follows. FIG. 5 is an explanatory diagram showing the state of each control level set in the control mode in the first embodiment.

[0052] The control unit 140 controls the vehicle 1 in the control mode selected by the switching unit 143. A damping force control unit 144 of the control unit 140 controls the damping force of the suspension system 30. As shown in Fig. 5 , the switching unit 143 switches between a normal mode in which damping force control is performed at a normal strength, a comfort mode in which damping force control is performed at a strength softer than normal, and a sport mode in which damping force control is performed at a strength harder than normal, based on the frequency of vibration of the vehicle 1, which is based on the road surface undulations and vehicle speed, and vehicle characteristic information 151.

[0053] The spring constant switching control unit 145 of the control unit 140 executes spring constant switching control of the suspension system 30. As shown in Fig. 5, the switching unit 143 switches between a normal mode in which the spring constant switching control is performed at a normal strength, a comfort mode in which the spring constant switching control is performed at a strength softer than that in the normal mode, and a sport mode in which the spring constant switching control is performed at a strength harder than that in the normal mode, based on the frequency of vibration of the vehicle 1, which is based on the road surface undulations and the vehicle speed, and vehicle characteristic information 151.

[0054] The steering control unit 146 of the control unit 140 executes steering control of the steering system 13. As shown in Fig. 5, the switching unit 143 switches between a normal mode in which the control gain in steering control is set to a normal level, a comfort mode in which the control gain is set lower than in the normal mode, and a sport mode in which the control gain is set higher than in the normal mode, based on the vibration frequency of the vehicle 1 based on the road surface undulations and the vehicle speed, and vehicle characteristic information 151.

[0055] The stabilizer control unit 147 of the control unit 140 executes stabilizer control of the vehicle 1. As shown in Fig. 5, based on the frequency of vibration of the vehicle 1 based on the road surface undulations and the vehicle speed, and vehicle characteristic information 151, the switching unit 143 switches between a normal mode in which the stabilizer control is performed at a normal intensity, a comfort mode in which the stabilizer control is performed at a softer intensity than in the normal mode, and a sport mode in which the stabilizer control is performed at a harder intensity than in the normal mode.

[0056] Next, a vehicle control process performed by the vehicle control system 100 according to this embodiment configured as described above will be described. FIG. 6 is a flowchart showing an example of a procedure for vehicle control processing by the vehicle control system 100 according to the first embodiment.

[0057] First, the acquisition unit 141 acquires an image of the road surface ahead, which is the traveling direction of the vehicle 1, captured by the imaging unit 15c (S11). The analysis unit 142 analyzes the captured image acquired by the acquisition unit 141 and determines the undulation state of the road surface (S13).

[0058] Next, the switching unit 143 calculates the vehicle speed of the vehicle 1 from the detection signal of the wheel speed sensor 22 acquired by the acquisition unit 141 (S17). Next, the switching unit 143 calculates the frequency of vibration of the vehicle 1 from the undulation state of the road surface and the vehicle speed (S19). Next, the switching unit 143 refers to the vehicle characteristic information 151 in the storage unit 150, and determines the control mode determined in the vehicle characteristic information 151 from the frequency of vibration of the vehicle 1 (S21).

[0059] For example, the threshold for switching the control mode is a vehicle characteristic felt by a passenger, such as frequency or unevenness level, and when the switching unit 143 determines that the pitching vibration level in the mid-frequency band (4 to 8 Hz) is equal to or greater than a first threshold (dB) based on the speed of the vehicle 1 and the undulations of the road surface ahead, the switching unit 143 switches the control mode from the normal mode to the comfort mode. Also, when the switching unit 143 determines that the pitching vibration level in the low-frequency band (1 to 3 Hz) is equal to or greater than a second threshold (dB) based on the speed of the vehicle 1 and the undulations of the road surface ahead, based on an analysis of the captured image, the switching unit 143 switches the control mode from the comfort mode to the normal mode.

[0060] Then, in the control unit 140, each control unit executes each control in the control mode determined by the switching unit 143 (S23).

[0061] As described above, in the present embodiment, in the vehicle control system 100, the analysis unit 142 analyzes road surface conditions from an image captured by the imaging unit 15c that captures an image of the road surface in the traveling direction of the vehicle 1, the switching unit 143 switches the control mode indicating the level of control related to the vehicle's traveling based on the road surface conditions and the vehicle characteristics based on the detection information by the on-board sensors, and the control unit 140 controls the vehicle 1 in the switched control mode. Therefore, according to the present embodiment, for example, it is possible to switch to an optimal control mode based on the vehicle characteristics in accordance with the road surface conditions, thereby reducing the burden on the user.

[0062] Furthermore, in this embodiment, the vehicle characteristics include heave characteristics, roll characteristics, and pitch characteristics of the vehicle 1, which are based on vertical acceleration, lateral acceleration, or longitudinal acceleration detected by an acceleration sensor serving as an on-board sensor, or the vehicle height of the vehicle detected by a vehicle height sensor serving as an on-board sensor. Therefore, according to this embodiment, as an example, the control mode is switched using the vehicle characteristics related to heave, roll, and pitch of the vehicle 1 as thresholds, and it is possible to switch to a more optimal control mode based on the heave, roll, or pitch characteristics of the vehicle depending on the road surface conditions, thereby further reducing the burden on the user.

[0063] Furthermore, in this embodiment, the switching unit 143 determines the road surface undulation state as one of rough, normal, and flat as the road surface condition, and switches the control mode between a plurality of modes with different levels of control intensity based on the road surface undulation state and vehicle characteristics. Therefore, according to this embodiment, as an example, it is possible to switch to an optimal control mode based on the vehicle characteristics in accordance with the road surface undulation state, thereby further reducing the burden on the user. In particular, according to this embodiment, even when there is no driver and the passengers cannot grasp the road surface condition, such as when the vehicle 1 is an autonomous vehicle, it is possible to switch to an optimal control mode based on the vehicle characteristics in accordance with the road surface undulation state, which is convenient for the passengers.

[0064] Furthermore, in this embodiment, the control modes corresponding to the road surface conditions and vehicle characteristics are predetermined as vehicle characteristic information 151 in storage unit 150, and switching unit 143 switches to the control mode determined corresponding to the road surface conditions and vehicle characteristics by referring to this vehicle characteristic information 151. Therefore, according to this embodiment, as an example, if the vehicle characteristics are determined in advance before shipping, there is no need to install an on-board sensor for determining the vehicle characteristics in vehicle 1 to be shipped, and therefore it is possible to reduce the installation space in vehicle 1 and the manufacturing costs of vehicle 1.

[0065] Furthermore, in this embodiment, the switching unit 143 calculates the frequency of the road surface undulations from the road surface conditions and the speed of the vehicle 1, and switches the control mode based on the calculated frequency and vehicle characteristics. Therefore, according to this embodiment, as an example, it is possible to switch to a more optimal control mode based on the vehicle characteristics in accordance with the road surface undulations, thereby further reducing the burden on the user.

[0066] (Second embodiment) In the first embodiment, the control mode based on the vehicle characteristics was predetermined at the time of shipment using vehicle characteristic information 151, but in this second embodiment, an on-board sensor is installed in the vehicle 1, the vehicle characteristics are determined while the vehicle 1 is running, and the optimal control mode is learned from the sensor detection information and the vehicle characteristics.

[0067] The configuration of the vehicle 1 according to the second embodiment is similar to that of the first embodiment. 7 is an exemplary block diagram of a configuration of a vehicle control system 1100 provided in a vehicle according to the second embodiment. The vehicle control system 1100 according to the second embodiment includes a vertical acceleration sensor 1110a, a lateral acceleration sensor 1110b, a longitudinal acceleration sensor 1110c, and a vehicle height sensor 1102 in addition to the configuration of the vehicle control system 100 according to the first embodiment.

[0068] The vertical acceleration sensor 1110a detects acceleration acting in the vertical direction of the vehicle 1. The lateral acceleration sensor 1110b detects acceleration acting in the width direction (lateral direction) of the vehicle 1. The longitudinal acceleration sensor 1110c detects acceleration acting in the longitudinal direction of the vehicle 1. The vehicle height sensor 1102 detects the vehicle height of the vehicle 1.

[0069] In addition, in the vehicle control system 1100 according to the second embodiment, the functions executed by the ECU 1014 are different from those of the ECU 1014 of the first embodiment. Other configurations of the vehicle control system 1100 according to the second embodiment are similar to those of the first embodiment.

[0070] Next, an example of the functional configuration of the ECU 1014 included in the vehicle 1 according to the second embodiment will be described with reference to Fig. 8. Fig. 8 is a diagram illustrating an example of the functional configuration of the ECU 1014 included in the vehicle according to the second embodiment.

[0071] 8, the ECU 1014 according to this embodiment functions as a vehicle control device having at least an acquisition unit 141, an analysis unit 142, a switching unit 1143, a learning unit 1141, a control unit 140, and a storage unit 150. The acquisition unit 141, the analysis unit 142, the control unit 140, and the storage unit 150 are the same as those in the first embodiment.

[0072] The learning unit 1141 learns by inputting road surface conditions and detection information while the vehicle 1 is traveling, and changes the threshold value of the vehicle characteristics based on the road surface conditions and the detection information as a threshold value for switching the control mode, thereby changing the association with the control mode. The switching unit 1143 switches to the control mode changed by the learning unit 1141.

[0073] Through this learning process, the thresholds for the vehicle characteristics and the like for switching the control mode are set to thresholds that take into consideration the deterioration of the bushings and tires of the suspension system 30, which contribute to each control in the control unit 140. Note that a known method can be used as the learning process algorithm.

[0074] Next, a vehicle control process performed by the vehicle control system 1100 according to this embodiment configured as described above will be described. 9 and 10 are flowcharts showing an example of the procedure of the vehicle control process by the vehicle control system 1100 according to the second embodiment.

[0075] The processes from S11 to S23 are performed in the same manner as in the first embodiment, and the control mode is determined and each control is executed in the determined control mode in the same manner as in the first embodiment.

[0076] Next, the switching unit 1143 determines whether the determined control mode is appropriate (S25). Specifically, while driving under each control in the control mode, it determines whether the level of each control is actually appropriate.

[0077] If it is appropriate (S25: Yes), the process ends. On the other hand, if it is not appropriate (S25: No), the acquisition unit 141 acquires detection information from each sensor (S41). Specifically, the acquisition unit 141 acquires acceleration acting in the vertical direction of the vehicle 1 from the vertical acceleration sensor 1110a, acceleration acting in the width direction (lateral direction) of the vehicle 1 from the lateral acceleration sensor 1110b, acceleration acting in the longitudinal direction of the vehicle 1 from the longitudinal acceleration sensor 1110c, and vehicle height from the vehicle height sensor 1102.

[0078] Next, the learning unit 1141 calculates vehicle characteristics from the acceleration acting in the vertical direction of the vehicle 1 from the vertical acceleration sensor 1110a, the acceleration acting in the width direction of the vehicle 1 from the lateral acceleration sensor 1110b, the acceleration acting in the longitudinal direction of the vehicle 1 from the longitudinal acceleration sensor 1110c, and the vehicle height from the vehicle height sensor 1102, all of which are acquired by the acquisition unit 141 (S43).

[0079] Specifically, the learning unit 1141 calculates heave characteristics such as the heave speed of the vehicle 1 based on the acceleration acting in the vertical direction of the vehicle 1 detected by the vertical acceleration sensor and the vehicle height detected by the vehicle height sensor. The learning unit 1141 also calculates roll characteristics such as the roll speed of the vehicle 1 based on the acceleration acting in the width direction (lateral direction) of the vehicle 1 detected by the lateral acceleration sensor. Furthermore, the learning unit 1141 calculates pitch characteristics such as the pitch speed of the vehicle 1 based on the acceleration acting in the longitudinal direction of the vehicle 1 detected by the longitudinal acceleration sensor.

[0080] Next, the learning unit 1141 determines the control mode again based on the vibration frequency of the vehicle 1 calculated in S19 and the vehicle characteristics calculated in S43 (S45).The learning unit 1141 then performs a learning process by learning the road surface undulation state, vibration frequency, and vehicle characteristics for the re-determined control mode, and registering them in the vehicle characteristics information 151 in association with the control mode (S47).The control unit 140 then changes to the determined control mode and executes each control (S49).

[0081] For example, assume that the undulations of the road surface ahead, analyzed from the image captured by the imaging unit 15c, are determined to be smaller than they actually are due to factors such as the intensity of sunlight and the tilt of the sun. In such a case, even if the switching unit 1143 switches the control mode to an appropriate mode, for example, normal mode, it is considered that the vertical acceleration acting on the vehicle 1 will be greater than expected. In such a case, in S25, the switching unit 1143 determines that the respective control levels are not actually appropriate, and in S41, S43, and S45, the learning unit 1141 switches the control mode to comfort mode when the vertical acceleration learned so far is acting.

[0082] As described above, in this embodiment, the vehicle control system 1100 further includes a learning unit 1141 that inputs and learns the road surface conditions and the detection information while the vehicle 1 is traveling, and changes a predetermined control mode depending on the vehicle characteristics based on the road surface conditions and the detection information, and the switching unit 1143 switches to the changed control mode. Therefore, according to this embodiment, as an example, the threshold for switching the control mode can be dynamically changed while the vehicle 1 is traveling, so that the control mode can be switched to a more optimal control mode based on the vehicle characteristics in accordance with the road surface conditions, and the burden on the user can be more appropriately reduced.

[0083] (Variation) Various modifications of the above first and second embodiments are possible. For example, the switching units 143, 1143 may be configured to provide a voice input means in the vehicle cabin for acquiring road noise and other road surface conditions, for example, sounds generated due to unevenness of the road surface, and switch the control mode based on the road surface conditions and characteristics based on the sounds. Here, sounds generated due to unevenness of the road surface include sounds transmitted inside the vehicle cabin 2a as well as sounds measured outside the vehicle cabin 2a.

[0084] According to this modification, road surface conditions can be recognized with higher accuracy, so that the control mode can be switched to a more optimal mode depending on the road surface conditions, thereby further reducing the burden on the user.

[0085] Furthermore, for example, an acceleration sensor may be provided near the rod of the shock absorber of the suspension system 30, and the switching unit 143, 1143 may be configured to switch the control mode based on the road surface conditions and vehicle characteristics based on the acceleration of the rod of the shock absorber of the suspension system 30.

[0086] According to this modified example, road conditions can be recognized with higher accuracy, so that the control mode can be switched to a more optimal one based on vehicle characteristics in accordance with road conditions, thereby further reducing the burden on the user.

[0087] Furthermore, for example, acceleration sensors may be provided near the portion of the vehicle on the body 2 side of the suspension system 30 (also referred to as the sprung portion) and the portion of the vehicle 1 on the wheel 3 side of the suspension system 30 (also referred to as the unsprung portion), and the switching units 143, 1143 may be configured to switch the control mode based on the road surface conditions (undulations) and vehicle characteristics based on the sprung acceleration or the unsprung acceleration.

[0088] According to this modified example, road conditions can be recognized with higher accuracy, so that the control mode can be switched to a more optimal one based on vehicle characteristics in accordance with road conditions, thereby further reducing the burden on the user.

[0089] Furthermore, in addition to switching the control modes of each control unit collectively as in the above embodiment, the switching unit 1143 may be configured to switch the control modes of each control unit individually or in combination based on vehicle characteristics, etc.

[0090] For example, consider the above-mentioned example, i.e., a case where the undulations of the road surface ahead, analyzed from the image captured by the imaging unit 15c, are determined to be smaller than they actually are due to factors such as the intensity of sunlight and the tilt of the sun. In such a case, even if the control mode is switched to an appropriate mode, for example, the normal mode, by the switching unit 1143, it is likely that the vertical acceleration will be greater than expected. In this case, if the level of road noise becomes greater than expected when the vertical acceleration learned so far acts, the learning unit 1141 and the switching unit 1143 may be configured to switch only the damping force control unit 144 and the spring constant switching control unit 145 to an appropriate level, for example, soft.

[0091] According to this modified example, the threshold for switching control modes can be changed more flexibly while the vehicle 1 is traveling, so that the control mode can be switched to a more optimal one based on the vehicle characteristics and road conditions, thereby further reducing the burden on the user.

[0092] In the above-described embodiment and variant examples, the CPU 14a reads and executes programs stored in a storage device such as the ROM 14b or the SSD 14f, thereby realizing various functional modules such as the acquisition unit 141, the analysis unit 142, the switching units 143, 1143, the learning unit 1141, the damping force control unit 144, the spring constant switching control unit 145, the steering control unit 146, and the stabilizer control unit 147.

[0093] In the above embodiment and modified examples, various functional modules such as the acquisition unit 141, the analysis unit 142, the switching units 143 and 1143, the learning unit 1141, the damping force control unit 144, the spring constant switching control unit 145, the steering control unit 146, and the stabilizer control unit 147 are realized by a processor such as the CPU 14a reading and executing programs stored in a storage device such as the ROM 14b or the SSD 14f. However, this is not limited to this. For example, the various functional modules such as the acquisition unit 141, the analysis unit 142, the switching units 143 and 1143, the learning unit 1141, the damping force control unit 144, the spring constant switching control unit 145, the steering control unit 146, and the stabilizer control unit 147 can also be realized by independent hardware. The vehicle control programs executed by the vehicle control devices and vehicle control systems 100 and 1100 of the above-described embodiment and modified examples are provided in a state that they are pre-installed in a ROM or the like.

[0094] The vehicle control programs executed by the vehicle control devices and vehicle control systems 100, 1100 of the above embodiments and variations may be configured to be provided by being recorded in an installable or executable format on a computer-readable recording medium such as a CD-ROM, a flexible disk (FD), a CD-R, or a DVD (Digital Versatile Disk).

[0095] Furthermore, the vehicle control programs executed by the vehicle control devices and vehicle control systems 100, 1100 of the above embodiments and modifications may be stored on a computer connected to a network such as the Internet and provided by being downloaded via the network. Also, the vehicle control programs executed by the vehicle control devices and vehicle control systems 100, 1100 of the above embodiments and modifications may be provided or distributed via a network such as the Internet.

[0096] The vehicle control program executed by the vehicle control device and vehicle control system 100, 1100 of the above-mentioned embodiment and modified example has a modular structure including the above-mentioned units (acquisition unit 141, analysis unit 142, switching unit 143, 1143, learning unit 1141, damping force control unit 144, spring constant switching control unit 145, steering control unit 146, stabilizer control unit 147, etc.), and in actual hardware, the CPU reads and executes the vehicle control program from the above-mentioned ROM, loading the above-mentioned units onto the main memory device, and the acquisition unit 141, analysis unit 142, switching unit 143, 1143, learning unit 1141, damping force control unit 144, spring constant switching control unit 145, steering control unit 146, stabilizer control unit 147, etc. are generated on the main memory device.

[0097] Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0098] 1...vehicle, 2...vehicle body, 14,1014...ECU, 15,15a,15b,15c,15d...imaging unit, 22...wheel speed sensor, 30...suspension system, 100, 1100...vehicle control system, 140...control unit, 141...acquisition unit, 142...analysis unit, 143,1143...switching unit, 144...damping force control unit, 145...spring constant switching control unit, 146...steering control unit, 147...stabilizer control unit, 150...memory unit, 151...vehicle characteristic information, 1102...vehicle height sensor, 1110a...vertical acceleration sensor, 1110b...lateral acceleration sensor, 1110c...longitudinal acceleration sensor, 1141...learning unit.

Claims

1. an analysis unit that analyzes road surface conditions from an image captured by an imaging device that captures an image of the road surface in the traveling direction of the vehicle; a switching unit that switches a control mode indicating a level of control related to the driving of the vehicle based on the road surface conditions and vehicle characteristics based on detection information by an on-board sensor; a control unit that controls the vehicle in the switched control mode; a learning unit that learns by inputting the road surface condition and the detection information while the vehicle is traveling, and changes a predetermined control mode in response to the vehicle characteristics based on the road surface condition and the detection information, The switching unit switches to the changed control mode. Vehicle control device.

2. The vehicle characteristics include heave characteristics, roll characteristics, or pitch characteristics of the vehicle based on vertical acceleration, lateral acceleration, or longitudinal acceleration detected by an acceleration sensor as the on-vehicle sensor, or a vehicle height of the vehicle detected by a vehicle height sensor as the on-vehicle sensor. The vehicle control device according to claim 1 .

3. The analysis unit determines the road surface condition as one of rough, normal, and flat, based on the undulations of the road surface; the switching unit switches the control mode between a plurality of modes having different levels of control intensity based on the undulation state of the road surface and the vehicle characteristics. The vehicle control device according to claim 2.

4. the control mode corresponding to the road surface condition and the vehicle characteristic is determined in advance, the switching unit switches to the control mode determined in accordance with the road surface conditions and the vehicle characteristics. The vehicle control device according to any one of claims 1 to 3.

5. the switching unit calculates a frequency of the undulation state of the road surface from the road surface condition and the vehicle speed, and switches the control mode based on the calculated frequency and the vehicle characteristics. The vehicle control device according to claim 3.

6. The switching unit further switches the control mode based on the road surface condition and the vehicle characteristics based on the sound generated by the road surface condition. The vehicle control device according to claim 3.

7. the control unit includes a damping force control of a suspension of the vehicle, The switching unit further switches the control mode based on the road surface condition and the vehicle characteristics based on the acceleration of a rod of a shock absorber of the suspension or the sprung acceleration or unsprung acceleration of the suspension. The vehicle control device according to claim 3.

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