Vehicle control device

Abstract

The vehicle control device of the embodiment performs the following processing. In the steering control when the vehicle is made to travel around a turn in a case where the vehicle is made to travel along a target path, feedforward control using a target curvature based on the target path is performed, and feedback control using a lateral deviation and a yaw angle deviation of the vehicle is performed. In this case, smoothing processing for smoothing the change is performed on the lateral deviation and the yaw angle deviation, and a target steering angle is calculated using the processing result.

Description

TECHNICAL FIELD

[0001] Embodiments of the present application relate to a vehicle control device. BACKGROUND

[0002] In the past, development of a technology for causing a vehicle to travel along a target path has been promoted. In this technology, in steering control when causing the vehicle to travel in a turn, for example, feedforward control using a target curvature based on the target path is performed, and feedback control using a lateral deviation and a yaw angle deviation of the vehicle is performed.

[0003] In such a technology, there is a technology for interrupting feedback control or attenuating a feedback gain, for example, when a deviation of a coordinate axis of a target parking frame recognized by the vehicle is large, for the purpose of preventing unnatural steering control.

[0004] PRIOR ART DOCUMENTS

[0005] PATENT DOCUMENTS

[0006] Patent Document 1: Japanese Patent Application Publication No. 2020-59330 SUMMARY

[0007] PROBLEMS TO BE SOLVED BY THE INVENTION

[0008] However, in the above-described prior art, for example, the following problem can occur. First, assume that the current estimated position of the vehicle deviates from the target path, and steering control by feedback control is performed to move in a turn to move the vehicle toward the target path. At this time, the target path is updated, and there is a case where the current estimated position of the vehicle suddenly lies on the target path. In this case, the lateral deviation and the yaw angle deviation of the vehicle suddenly become 0 (or a value close to 0), and therefore, by feedback control, there can occur a sharp steering for shifting from the turn movement to the straight movement, which is not ideal in terms of the ride feeling of an occupant or the like.

[0009] Therefore, the present application was completed in view of the above-described circumstances, and an object thereof is to provide a vehicle control device that can avoid a sharp steering even when a sudden change occurs in a lateral deviation and a yaw angle deviation of a vehicle in a case where the vehicle is caused to travel along a target path.

[0010] MEANS FOR SOLVING THE PROBLEMS

[0011] To address the aforementioned issues, the vehicle control device of the embodiment, when driving the vehicle along a target path, performs feedforward control based on the target curvature of the target path and feedback control based on the vehicle's lateral deviation and yaw angle deviation during steering control when the vehicle is turning. It includes: a vehicle position estimation unit that estimates the current position of the vehicle and outputs vehicle position information; a lateral deviation calculation unit that calculates the deviation between the actual lateral position of the vehicle and the target lateral position based on the target path, i.e., the lateral deviation, based on the target path and the vehicle position information; and a first filtering processing unit that inputs the lateral deviation and executes... A first smoothing process is used to smooth out the changes in the lateral deviation, and outputs the corrected lateral deviation; a yaw angle deviation calculation unit calculates the deviation between the actual yaw angle of the vehicle and the target yaw angle based on the target path and the vehicle position information, i.e., the yaw angle deviation; a second filtering processing unit takes the yaw angle deviation as input, performs a second smoothing process to smooth out the changes in the yaw angle deviation, and outputs the corrected yaw angle deviation; a target steering angle calculation unit calculates the target steering angle based on the target curvature based on the target path, the corrected lateral deviation, and the corrected yaw angle deviation; and a control unit controls the steering based on the target steering angle.

[0012] According to this structure, even if there are sudden changes in the lateral deviation and yaw angle deviation of the vehicle, it is possible to avoid sharp turns while the vehicle is traveling along the target path. Attached Figure Description

[0013] Figure 1 It is an illustrative perspective view showing a portion of the vehicle's passenger compartment in the embodiment being viewed from a distance.

[0014] Figure 2 This is an illustrative top view (overhead view) of the vehicle in the embodiment.

[0015] Figure 3 This is an example of a vehicle's dashboard as seen from the rear of the vehicle.

[0016] Figure 4 This is an exemplary block diagram illustrating the structure of a vehicle control system according to an implementation method.

[0017] Figure 5 This is a diagram of the steering control block in the implementation method.

[0018] Figure 6 This is an explanatory diagram regarding the updating of the target path in the implementation method.

[0019] Figure 7 This is a graph showing examples of the time transition of various information in the implementation method.

[0020] Figure 8 This is a flowchart illustrating the processes related to steering control in the implementation method. Detailed Implementation

[0021] Hereinafter, exemplary embodiments of the present invention are disclosed. The structures of the embodiments shown below, as well as the effects, results, and outcomes resulting from these structures, are examples. The present invention can also be implemented using structures other than those disclosed in the following embodiments, and at least one of various effects and derived effects based on the basic structure can be obtained.

[0022] The vehicle 1 in this embodiment can be, for example, an automobile powered by an internal combustion engine (not shown), an electric vehicle, or a fuel cell vehicle powered by an electric motor (not shown), a hybrid vehicle powered by both, or a vehicle with other drive sources. Furthermore, the vehicle 1 can be equipped with various transmission devices and various devices required to drive the internal combustion engine and electric motor, such as systems and components. Additionally, the method, number, and layout of devices related to the drive of the wheels 3 in the vehicle 1 can be configured in various ways.

[0023] Figure 1 This is an illustrative perspective view showing a portion of the vehicle's passenger compartment in a perspective embodiment. Figure 2 This is an illustrative top view (overhead view) of the vehicle in the embodiment.

[0024] like Figure 1 As illustrated, the vehicle body 2 constitutes a passenger compartment 2a for passengers (not shown). Inside the passenger compartment 2a, in a position facing the driver's seat 2b, there are a steering unit 4, an acceleration control unit 5, a braking control unit 6, a transmission control unit 7, etc.

[0025] Steering unit 4 is, for example, a steering wheel protruding from the instrument panel 24. Acceleration control unit 5 is, for example, an accelerator pedal located under the driver's feet. Braking control unit 6 is, for example, a brake pedal located under the driver's feet. Shift control unit 7 is, for example, a gear lever protruding from the center console. However, steering unit 4, acceleration control unit 5, braking control unit 6, and shift control unit 7 are not limited to these.

[0026] In addition, a display device 8 serving as a display output unit and a sound output device 9 serving as a sound output unit are provided inside the carriage 2a. The display device 8 is, for example, an LCD (liquid crystal display) or an OELD (organic electroluminescent display). The sound output device 9 is, for example, a speaker. Furthermore, the display device 8 is covered by a transparent operation input section 10, such as a touch panel. Passengers can visually confirm the image displayed on the display screen of the display device 8 through the operation input section 10. In addition, passengers can perform operation input by touching, pressing, moving, or performing other operations on the operation input section 10 at positions corresponding to the image displayed on the display screen of the display device 8.

[0027] These components, such as the display device 8, sound output device 9, and operation input unit 10, are, for example, located in the center of the instrument panel 24 in the vehicle width direction, i.e., the left-right direction, as part of the monitoring device 11. The monitoring device 11 can have operation input units (not shown), such as switches, dials, joysticks, and buttons. Additionally, a sound output device (not shown) can be installed in another location within the passenger compartment 2a, different from the monitoring device 11. Furthermore, sound can be output from the sound output device 9 of the monitoring device 11 and other sound output devices. Moreover, the monitoring device 11 can, for example, also function as a navigation system and an audio system.

[0028] In addition, a display device 12, which is different from the display device 8, is installed in the carriage 2a (see reference). Figure 3 ). Figure 3 This is an example of a vehicle's dashboard as seen from the rear of the vehicle. Figure 3 As illustrated, the display device 12 is, for example, disposed in the instrument panel section 25 of the instrument panel 24, approximately in the center of the instrument panel section 25, between the speed display section 25a and the tachometer display section 25b. The screen size of the display device 12 is larger than that of the display device 8. Figure 1 The size is small. The display device 12 is primarily capable of displaying images representing information related to the driving control of the vehicle 1 (e.g., parking assist control). The amount of information displayed by the display device 12 can also be less than the amount of information displayed by the display device 8. The display device 12 is, for example, an LCD, an OLED, etc. Furthermore, the information displayed by the display device 12 can also be displayed on the display device 8.

[0029] In addition, such as Figure 1 as well as Figure 2 As illustrated, vehicle 1 is, for example, a four-wheeled automobile, having two front wheels 3F on the left and right and two rear wheels 3R ​​on the left and right. All four wheels 3 can be configured to be steerable.

[0030] Figure 4This is an illustrative block diagram illustrating the structure of a vehicle control system according to an implementation method. For example... Figure 4 As illustrated, vehicle 1 has an EPS13 (Electric Power Steering system) that steers at least two wheels 3. EPS13 has an actuator 13a and a torque sensor 13b. EPS13 is electrically controlled by an ECU14 (electronic control unit), which actuates the actuator 13a. In the following description, EPS13 refers to an electric power steering system, SBW (steer-by-wire) system, etc. EPS13 uses the actuator 13a to apply torque, i.e., auxiliary torque, to the steering unit 4 to supplement the steering force, or uses the actuator 13a to steer the wheels 3. In this case, the actuator 13a can steer one wheel 3 or multiple wheels 3. Additionally, the torque sensor 13b detects, for example, the torque applied to the steering unit 4 by the driver.

[0031] In addition, such as Figure 2 As illustrated, the vehicle body 2 is provided with a plurality of imaging units 15, for example, four imaging units 15a to 15d. The imaging unit 15 is, for example, a digital camera with built-in imaging elements such as CCD (charge coupled device) and CIS (CMOS image sensor). The imaging unit 15 is capable of outputting moving image data at a specified frame rate.

[0032] In addition, such as Figure 1 and Figure 2 As illustrated, the vehicle body 2 is provided with, for example, four ranging units 16a-16d and eight ranging units 17a-17h as a plurality of ranging units 16, 17. The ranging units 16, 17 are, for example, sonar that emits ultrasonic waves and captures their reflected waves. Sonar can also be called a sonar sensor or an ultrasonic detector. Based on the detection results of the ranging units 16, 17, the ECU 14 is able to determine the presence or absence of obstacles or other objects around the vehicle 1 and the distance to those objects.

[0033] In addition, such as Figure 4 As illustrated, in the vehicle control system 100 that enables the vehicle to travel along the target path, in addition to the ECU 14, monitoring device 11, EPS 13, distance measuring unit 16, 17, etc., the braking system 18, steering angle sensor 19, acceleration sensor 20, gear position sensor 21, wheel speed sensor 22, etc. are also electrically connected via the in-vehicle network 23, which serves as an electrical communication line.

[0034] The in-vehicle network 23 is configured, for example, as a CAN (Controller Area Network). The ECU 14 sends control signals through the in-vehicle network 23, thereby controlling the EPS 13, braking system 18, etc. In addition, the ECU 14 can receive detection results from torque sensor 13b, brake sensor 18b, steering angle sensor 19, distance measuring unit 16, distance measuring unit 17, acceleration sensor 20, gear position sensor 21, wheel speed sensor 22, etc., and operation signals from operation input unit 10, etc., via the in-vehicle network 23.

[0035] like Figure 4 As shown, the ECU14 may include, for example, a CPU14a (central processing unit), a ROM14b (read-only memory), a RAM14c (random access memory), a display control unit 14d, a sound control unit 14e, and an SSD14f (solid state drive, flash memory).

[0036] CPU 14a can perform various operations and controls, such as image processing related to the image displayed on display device 812, determining the moving target position of vehicle 1, calculating the moving path of vehicle 1, determining whether there is interference with objects, automatic control of vehicle 1, and deactivation of automatic control. CPU 14a can read programs installed and stored in non-volatile storage devices such as ROM 14b and perform operations according to the programs.

[0037] RAM 14c temporarily stores various data used in the operations of CPU 14a. Additionally, the display control unit 14d, during the ECU 14's processing, primarily performs image processing using image data obtained from the imaging unit 15, and synthesizing image data displayed by display devices 8 and 12. Furthermore, the sound control unit 14e, during the ECU 14's processing, primarily processes the sound data output from the sound output device 9. Finally, the SSD 14f is a rewritable, non-volatile storage unit that can store data even when the power to the ECU 14 is disconnected.

[0038] Furthermore, CPU14a, ROM14b, RAM14c, etc., can be integrated into the same package. Alternatively, ECU14 can be configured to replace CPU14a by using other logic processors or logic circuits such as DSP (digital signal processor). Additionally, HDD (hard disk drive) can replace SSD14f; SSD14f and HDD can also be configured separately from ECU14.

[0039] The braking system 18 may be, for example, an ABS (anti-lock brake system) to prevent brake lock-up, an ESC (electronic stability control) to prevent skidding of the vehicle 1 during cornering, an electric braking system to enhance braking force (perform brake assist), or BBW (brake by wire). The braking system 18 applies braking force to the wheels 3 and thus to the vehicle 1 via actuators 18a.

[0040] Furthermore, the braking system 18 can detect brake lock-up, wheel spin, and signs of sideslip based on the rotational difference between the left and right wheels 3, and perform various controls accordingly. The brake sensor 18b is, for example, a sensor that detects the position of the movable part of the brake operating unit 6. The brake sensor 18b can detect the position of the brake pedal, which is the movable part of the brake operating unit 6. The brake sensor 18b includes a displacement sensor.

[0041] The steering angle sensor 19 is, for example, a sensor that detects the amount of steering of the steering unit 4, such as a steering wheel. The steering angle sensor 19 is constructed using, for example, a Hall element. The ECU 14 obtains 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 to perform various controls. In addition, the steering angle sensor 19 detects the rotation angle of the rotating parts included in the steering unit 4.

[0042] Acceleration sensor 20 is, for example, a sensor that detects the position of the movable part of acceleration operation unit 5. Acceleration sensor 20 can detect the position of the accelerator pedal, which is the movable part of acceleration operation unit 5. Acceleration sensor 20 includes a displacement sensor.

[0043] The gear position sensor 21 is, for example, a sensor that detects the position of the movable part of the gear shifting unit 7. The gear position sensor 21 can detect the position of a lever, arm, button, etc., which are movable parts of the gear shifting unit 7. The gear position sensor 21 can include a displacement sensor or be configured as a switch.

[0044] Wheel speed sensor 22 is a sensor that detects the amount of rotation of wheel 3, specifically the number of revolutions per unit time. Wheel speed sensor 22 outputs the number of wheel speed pulses representing the detected rotational speed as a sensor value. Wheel speed sensor 22 can be constructed using, for example, a Hall element. ECU 14 calculates the amount of movement of vehicle 1, etc., based on the sensor value obtained from wheel speed sensor 22, and performs various controls. Furthermore, there is also a case where wheel speed sensor 22 is installed in braking system 18. In this case, ECU 14 obtains the detection result from wheel speed sensor 22 via braking system 18.

[0045] Furthermore, the structure, configuration, and electrical connection methods of the various sensors and actuators mentioned above are just one example, and various settings (changes) can be made.

[0046] In this embodiment, the ECU 14 performs at least a portion of its functions as a vehicle control device through coordinated operation of hardware and software (control program). When the vehicle 1 is traveling along the target path, the ECU 14 performs feedforward control based on the target curvature of the target path and feedback control based on the lateral deviation and yaw angle deviation of the vehicle in the steering control when the vehicle 1 is turning.

[0047] The following shall also be referred to Figure 5 , Figure 6 Let me continue explaining. Figure 5 This is a block diagram of the steering control in the implementation method. Figure 6 This is an explanatory diagram related to the updating of the target path in the implementation method.

[0048] like Figure 6 As shown in (a), the current estimated position of vehicle 1 deviates from the target path R1, resulting in lateral deviation and yaw angle deviation of vehicle 1. There is a possibility that feedback control can be used to perform steering control to make turning movement so that vehicle 1 moves toward the target path.

[0049] At this point, the target path may be updated, such as... Figure 6 As shown in (b), the current estimated position of vehicle 1 suddenly falls on the target path R2. In this case, the lateral deviation and yaw angle deviation of vehicle 1 suddenly become 0 (or close to 0) (that is, a sudden change). Therefore, due to feedback control, a sharp turn is generated to change from turning movement to straight movement, which is not preferable in terms of occupant comfort. Therefore, the following describes a technique that can avoid sharp turns even when the lateral deviation and yaw angle deviation of vehicle 1 suddenly change while driving vehicle 1 along the target path.

[0050] Figure 5 The parts 201-209, 221, and 222 shown are, for example, ECU14 (Figure 4 This is achieved through the function of ).

[0051] The vehicle position estimation unit 201 uses the latest position information of the vehicle 1, the detection results of the wheel speed sensor 22, etc., to estimate the current position of the vehicle 1 and output the vehicle position information.

[0052] In addition, the deviation calculation unit 202 (lateral deviation calculation unit) calculates the deviation between the actual lateral position of vehicle 1 and the target lateral position based on the target path, i.e., the lateral deviation, based on the target path and vehicle position information.

[0053] The deviation calculation unit 202 (yaw angle deviation calculation unit) calculates the deviation between the actual yaw angle of vehicle 1 and the target yaw angle based on the target path and vehicle position information, i.e., the yaw angle deviation.

[0054] The first filtering processing unit 221 receives the lateral deviation from the deviation calculation unit 202 (lateral deviation calculation unit), performs a first smoothing process to smooth the change in lateral deviation, and outputs the corrected lateral deviation. Furthermore, in the first smoothing process, for example, a predetermined calculation is performed using the previous value and the current value of the lateral deviation to make the current value close to the previous value. Specifically, for example, the previous value can be added to the previous value by multiplying the value obtained by subtracting the previous value from the current value by a predetermined coefficient. However, this is not limited to this method, and other calculation formulas can also be used. The second smoothing process described below is similar. By performing smoothing processing (low-pass filtering), small changes caused by noise are removed, and the change in steering angle becomes smooth.

[0055] Additionally, for example, when the target path is updated ( Figure 6 (a) → Figure 6 (b) The first filtering processing unit 221 starts the first smoothing process and performs the first smoothing process until the corrected lateral deviation converges (for example, until it becomes below a specified lateral deviation threshold).

[0056] The second filtering processing unit 222 receives the yaw angle deviation from the deviation calculation unit 202 (yaw angle deviation calculation unit), performs a second smoothing process to smooth the change in the yaw angle deviation, and outputs the corrected yaw angle deviation. For example, when the target path is updated, the second filtering processing unit 222 starts the second smoothing process and performs the second smoothing process until the corrected yaw angle deviation converges (for example, until it becomes below a predetermined yaw angle deviation threshold).

[0057] The multiplication unit 203 multiplies the corrected lateral deviation output from the first filter processing unit 221 by the gain Ke.

[0058] The multiplication unit 204 multiplies the corrected yaw angle deviation output from the second filter processing unit 222 by the gain Kθ.

[0059] The addition unit 205 adds the value output from the multiplication unit 203 to the value output from the multiplication unit 204.

[0060] The addition / subtraction unit 206 adds the input target curvature (target curvature based on the target path) and subtracts the value output from the addition unit 205.

[0061] The target steering angle calculation unit 207 calculates the target steering angle based on the target curvature of the target path, the corrected lateral deviation (which is the lateral deviation if the first smoothing process of the first filtering processing unit 221 is not performed), and the corrected yaw angle deviation (which is the yaw angle deviation if the second smoothing process of the second filtering processing unit 222 is not performed). Specifically, the target steering angle calculation unit 207 calculates the target steering angle based on the target curvature output from the addition / subtraction unit 206 and the curvature / steering angle mapping 2071. The curvature / steering angle mapping 2071 is information representing the relationship between the target curvature and the steering angle.

[0062] The third filtering processing unit 208 performs a smoothing process (low-pass filtering) on ​​the target steering angle calculated by the target steering angle calculation unit 207. Through this smoothing process, minute changes caused by noise are removed, and the steering angle change becomes smooth.

[0063] The protection processing unit 209 performs protection processing on the target steering angle that has been smoothed by the third filtering processing unit 208, so that it does not exceed the preset maximum steering angle.

[0064] When driving the vehicle 1, the ECU14 (control unit) uses the EPS13 to control the steering based on the target steering angle output from the protection processing unit 209.

[0065] Figure 7 This is a graph showing examples of the time transitions of various pieces of information in the implementation method. Furthermore, Figure 7 The curves show the general changes, but are not limited to strict accuracy. (a) is the path update flag G1, which is "0" when the target path has not been updated, and becomes "1" only after the target path has just been updated.

[0066] (b) refers to lateral deviation and yaw angle deviation. Reference numeral G11 indicates the prior art, while reference numeral G12 indicates the present embodiment.

[0067] (c) is the target curvature, and the attached figure shows the value of G20 under FF (feedforward) control (by...). Figure 5The addition / subtraction unit 206 performs the addition of the value), and reference numeral G21 is the value under FB (feedback) control in the prior art (by...). Figure 5 The value subtracted by the addition / subtraction unit 206), reference numeral G22 is the value under FB control in this embodiment (by... Figure 5 The addition and subtraction section 206 performs the subtraction of the value.

[0068] (d) is the target steering angle. Reference numeral G31 indicates the prior art, and reference numeral G32 indicates the present embodiment.

[0069] Under the current technology, the target path is updated ( Figure 6 (a) → Figure 6 (b)), just as the path update flag changes to "1" ( Figure 7 After (a), the lateral deviation and yaw angle deviation suddenly become 0 (or close to 0). Figure 7 (b) with reference numeral G11). Therefore, due to the target curvature under FB control (by... Figure 5 The value of the subtraction in the addition and subtraction section 206 increases sharply ( Figure 7 (c) (reference numeral G21), therefore the target steering angle also increases sharply ( Figure 7 (d) (G31) produces a sharp turn.

[0070] On the other hand, in this embodiment, the target path is updated ( Figure 6 (a) → Figure 6 (b)), when the path update flag changes to "1" ( Figure 7 After (a), through the first smoothing process performed by the first filtering processing unit 221 and the second smoothing process performed by the second filtering processing unit 222, the lateral deviation and yaw angle deviation gradually decrease. Figure 7 (b) with reference numeral G12). Therefore, the target curvature in FB control (by... Figure 5 The value of the subtraction in addition / subtraction section 206 gradually increases ( Figure 7 (c) (reference numeral G22), therefore the target steering angle also gradually increases ( Figure 7 (d) (G32) does not produce a sharp turn.

[0071] Figure 8 This is a flowchart illustrating the steering control-related processes in the implementation method. Here, it is assumed that a target path is given, and ECU14 is executing steering control. Additionally, this is performed periodically. Figure 8 The processing.

[0072] In step S1, the vehicle position estimation unit 201 uses the latest position information of vehicle 1, the detection results of wheel speed sensor 22, etc., to estimate the current position of vehicle 1 and output the vehicle position information.

[0073] Next, in step S2, the deviation calculation unit 202 (lateral deviation calculation unit) calculates the lateral deviation based on the target path and vehicle position information.

[0074] Next, in step S3, the deviation calculation unit 202 (yaw angle deviation calculation unit) calculates the yaw angle deviation based on the target path and vehicle position information.

[0075] Next, in step S4, ECU14 determines whether the target path has been updated. If it is "yes", it proceeds to step S5; otherwise, it skips step S5.

[0076] In step S5, ECU14 sets the implementation flags of the first smoothing process and the second smoothing process to ON. Then, the processes in steps S6-S9 and steps S10-S13 are executed in parallel.

[0077] In step S6, the first filtering processing unit 221 determines whether the corrected lateral deviation has converged. If it is "yes", it proceeds to step S7; if it is "no", it proceeds to step S8.

[0078] In step S7, ECU14 sets the implementation flag of the first smoothing process to OFF.

[0079] In step S8, ECU14 determines whether the implementation flag of the first smoothing process is enabled (i.e., set to ON). If "yes", proceed to step S9; if "no", proceed to step S14.

[0080] In step S9, the first filtering processing unit 221 receives the lateral deviation calculated in step S2, performs a first smoothing process, and outputs the corrected lateral deviation. Alternatively, if step S9 is not performed, the lateral deviation calculated in step S2 is input to the multiplication unit 203.

[0081] In step S10, the second filtering processing unit 222 determines whether the corrected yaw angle deviation has converged. If it is "yes", it proceeds to step S11; if it is "no", it proceeds to step S12.

[0082] In step S11, ECU14 sets the implementation flag of the second smoothing process to OFF.

[0083] In step S12, ECU14 determines whether the implementation flag of the second smoothing process is enabled (i.e., set to ON). If "yes", it proceeds to step S13; if "no", it proceeds to step S14.

[0084] In step S13, the second filtering processing unit 222 receives the yaw angle deviation calculated in step S3, performs the second smoothing process, and outputs the corrected yaw angle deviation. Alternatively, if step S13 is not performed, the yaw angle deviation calculated in step S3 is input to the multiplication unit 204.

[0085] after, Figure 5 Multiplication part 203, multiplication part 204, addition part 205, and addition / subtraction part 206 perform each operation.

[0086] Next, in step S14, the target steering angle calculation unit 207 calculates the target steering angle based on the target curvature output from the addition and subtraction unit 206 and the curvature / steering angle mapping 2071.

[0087] Next, in step S15, the third filtering processing unit 208 performs smoothing processing (low-pass filtering processing) on ​​the target steering angle calculated in step S14.

[0088] Next, in step S16, the protection processing unit 209 performs protection processing on the target steering angle processed in step S15.

[0089] Next, in step S17, the ECU14 (control unit) uses the EPS13 to control the steering based on the target steering angle processed in step S16.

[0090] Thus, according to this embodiment, when the vehicle 1 is traveling along the target path, even if the lateral deviation and yaw angle deviation of the vehicle 1 change abruptly, sharp turns can be avoided through the action of the first filtering processing unit 221 and the second filtering processing unit 222 (each smoothing process). As a result, natural steering can be achieved, improving the riding experience of the occupants and increasing their sense of security.

[0091] Additionally, as a specific application scenario, when the target path is updated ( Figure 6 (a) → Figure 6 (b) By performing smoothing processes by the first filtering processing unit 221 and the second filtering processing unit 222, abrupt turns can be avoided.

[0092] However, the application scenarios are not limited to this. For example, steering control can also begin when the position of vehicle 1, as indicated by the vehicle position information estimated by the vehicle position estimation unit 201, deviates from the target path. In this case, in the prior art, a sharp turn may occur shortly after steering control begins. On the other hand, according to this embodiment, similar to the case when updating the target path, sharp turns can be avoided by performing smoothing processes by the first filtering processing unit 221 and the second filtering processing unit 222. In this case, the first filtering processing unit 221 also performs the first smoothing process until the corrected lateral deviation converges, and the second filtering processing unit 222 also performs the second smoothing process until the corrected yaw angle deviation converges.

[0093] Furthermore, the program executed by vehicle 1 can also be provided as a computer program product by storing it as an installable or executable file on a computer-readable storage medium such as a CD-ROM, CD-R, memory card, DVD (Digital Versatile Disk), or floppy disk (FD). Alternatively, the program can be stored on a computer connected to a network such as the Internet and provided by downloading it via the network. Additionally, the program can be provided or distributed via a network such as the Internet.

[0094] The embodiments of the present invention have been described above, but these embodiments are provided as examples and are not intended to limit the scope of the invention. This new embodiment can be implemented in various other ways, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. This embodiment and its variations are included within the scope and spirit of the invention, and are also included within the scope of the invention as described in the claims and its equivalents.

[0095] [Summary of this implementation method]

[0096] This embodiment has at least the following structure.

[0097] In steering control when the vehicle travels along a target path, the vehicle control device performs feedforward control based on the target curvature of the target path and feedback control based on the vehicle's lateral deviation and yaw angle deviation. It includes: a vehicle position estimation unit that estimates the vehicle's current position and outputs vehicle position information; a lateral deviation calculation unit that calculates the deviation between the vehicle's actual lateral position and the target lateral position based on the target path, i.e., the lateral deviation, based on the target path and the vehicle position information; and a first filtering processing unit that inputs the lateral deviation and performs actions to smooth the changes in the lateral deviation. The first smoothing process outputs the corrected lateral deviation; the yaw angle deviation calculation unit calculates the deviation between the actual yaw angle of the vehicle and the target yaw angle based on the target path and the vehicle position information, i.e., the yaw angle deviation; the second filtering processing unit inputs the yaw angle deviation, performs a second smoothing process to smooth the change in the yaw angle deviation, and outputs the corrected yaw angle deviation; the target steering angle calculation unit calculates the target steering angle based on the target curvature based on the target path, the corrected lateral deviation, and the corrected yaw angle deviation; and the control unit controls the steering based on the target steering angle.

[0098] With this structure, even when the vehicle's lateral deviation and yaw angle deviation change abruptly while traveling along the target path, sharp turns can be avoided through the smoothing processes of the first and second filtering units.

[0099] Additionally, when the target path is updated, the first filtering unit starts the first smoothing process and executes the first smoothing process until the corrected lateral deviation converges. The second filtering unit starts the second smoothing process and executes the second smoothing process until the corrected yaw angle deviation converges.

[0100] With this structure, when the target path is updated, abrupt turns can be avoided by performing smoothing processes by the first and second filtering units.

[0101] Furthermore, when steering control is initiated when the vehicle's position, as indicated by the vehicle position information, deviates from the target path, the first filtering processing unit initiates the first smoothing process and executes the first smoothing process until the corrected lateral deviation converges. The second filtering processing unit then initiates the second smoothing process and executes the second smoothing process until the corrected yaw angle deviation converges.

[0102] With this structure, even when the vehicle's position, as indicated by the estimated vehicle position information, deviates from the target path, sharp turns can be avoided through smoothing processes performed by the first and second filtering units, even after steering control has been initiated.

[0103] Furthermore, the effects of dependents and embodiments in the claims are additional effects that differ from the effects of independent claims in the claims.

[0104] Explanation of reference numerals in the attached figures

[0105] 1 Vehicle, 14 ECUs, 201 Vehicle Position Estimation Unit, 202 Deviation Calculation Unit, 207 Target Steering Angle Calculation Unit, 221 First Filter Processing Unit, 222 Second Filter Processing Unit

Claims

1. A vehicle control device, in steering control for driving a vehicle along a target path, performs feedforward control based on the target curvature of the target path, and performs feedback control using the vehicle's lateral deviation and yaw angle deviation, wherein... have: The vehicle position estimation unit estimates the current position of the vehicle and outputs the vehicle position information; The lateral deviation calculation unit calculates the deviation between the actual lateral position of the vehicle and the target lateral position based on the target path, i.e., the lateral deviation, based on the target path and the vehicle position information. The first filtering processing unit takes the lateral deviation as input, performs a first smoothing process to smooth the change in the lateral deviation, and outputs the corrected lateral deviation. The yaw angle deviation calculation unit calculates the deviation between the actual yaw angle of the vehicle and the target yaw angle based on the target path and the vehicle position information, i.e., the yaw angle deviation. The second filtering processing unit takes the yaw angle deviation as input, performs a second smoothing process to smooth the change in the yaw angle deviation, and outputs the corrected yaw angle deviation. The target steering angle calculation unit calculates the target steering angle based on the target curvature of the target path, the corrected lateral deviation, and the corrected yaw angle deviation. as well as The control unit controls the steering based on the target steering angle.

2. The vehicle control device according to claim 1, wherein, If the target path is updated The first filtering unit begins the first smoothing process and executes it until the corrected lateral deviation converges. The second filtering processing unit begins the second smoothing process and executes the second smoothing process until the corrected yaw angle deviation converges.

3. The vehicle control device according to claim 1, wherein, When the steering control is initiated when the vehicle's position, as indicated by the vehicle position information, deviates from the target path. The first filtering unit begins the first smoothing process and executes it until the corrected lateral deviation converges. The second filtering unit begins the second smoothing process and executes the second smoothing process until the corrected yaw angle deviation converges.

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