DRIVING ASSISTANCE DEVICE

Abstract

Driving assistance device (20) that provides driving assistance to a vehicle (10) based on environmental information collected by a plurality of sensors (14a to 14l, 16a to 16d) provided in the vehicle (10), the driving assistance device (20) comprising: a route calculation unit (204) configured to calculate a movement route of the vehicle (10) to a target position based on the environmental information from the plurality of sensors (14a to 14l, 16a to 16d); a switching unit (205) configured to switch settings of an upper limit of the acceleration of the vehicle (10) between a first acceleration limit (LVd) and a second acceleration limit (LVe) that is lower than the first acceleration limit (LVd);and a motion control unit (206) configured to move the vehicle (10) along the motion route while steering the vehicle (10) with an acceleration within the upper limit set by the switching unit (205), wherein the switching unit (205) sets the upper limit of the acceleration of the vehicle (10) to the second acceleration limit (LVe) in a case where the vehicle (10) is stopped and a steering angle of the vehicle (10) during steering of the vehicle (10) by the motion control unit (206) is equal to or greater than a predetermined threshold.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a driving assistance device. BACKGROUND

[0002] There is a driving assistance device that automatically parks and exits a vehicle into and out of a parking space. During execution of the driving assistance, an upper limit for the vehicle's acceleration is set, and the vehicle is controlled at an acceleration within the upper limit.

[0003] For example, in the technique of WO 2020 / 066331 A, it is possible to stop a vehicle at a target position by setting an acceleration profile, which is a temporal change of a target acceleration value at the time of deceleration of the vehicle according to a distance to the target position. Furthermore, in the technique of JP 5 257 647 B2, the acceleration of a vehicle is limited within an upper acceleration limit set according to a vehicle speed, making it possible to prevent the occurrence of an unexpected acceleration condition.

[0004] However, if a vehicle is to be started from a stopped state with a steering angle equal to or greater than a predetermined angle, the vehicle is likely to be shaken even if the vehicle is controlled at an acceleration within the upper limit. WO 2020 / 066331 A and JP 5257647 B2 do not consider this point, and there is a concern that shaking a vehicle may lead to a deterioration in the ride comfort of the occupants, including the driver.

[0005] There is therefore a need for a driving assistance device that can improve the driving comfort of a vehicle occupant by preventing shaking during the execution of the driving assistance. SUMMARY

[0006] To solve the problems described above and achieve the object, a driving assistance device of one embodiment is a driving assistance device that performs driving assistance of a vehicle based on environmental information collected by a plurality of sensors provided in the vehicle, the driving assistance device comprising: a route calculation unit configured to calculate a movement route of the vehicle to a target position based on the environmental information from the plurality of sensors; a switching unit configured to switch settings of an upper limit value of acceleration of the vehicle between a first acceleration limit value and a second acceleration limit value that is smaller than the first acceleration limit value;and a motion control unit configured to move the vehicle along the movement route while controlling the vehicle at an acceleration within the upper limit set by the switching unit, wherein the switching unit sets the upper limit of the acceleration of the vehicle to the second acceleration limit in a case where the vehicle is stopped and a steering angle of the vehicle is equal to or greater than a predetermined threshold during control of the vehicle by the motion control unit.

[0007] The driving assistance device of the embodiment can improve the driving comfort of a vehicle occupant by preventing shaking during execution of the driving assistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The foregoing and additional features and characteristics of this disclosure will become more apparent from the following detailed description considered with reference to the accompanying drawings, in which: Fig. 1 is a plan view of a vehicle on which a driving assistance device according to an embodiment is mounted; Fig. 2 is a block diagram showing an example of the overall configuration of a driving support system according to the embodiment; Fig. 3 is a block diagram illustrating an example of a functional configuration of the driving support device according to the embodiment; Fig. 4 is a diagram illustrating an example of settings of acceleration limit values ​​held by the driving support device according to the embodiment; and Fig. 5 is a flowchart illustrating a process example of a driving support process by the driving support device according to the embodiment. DETAILED DESCRIPTION

[0009] In the following exemplary embodiment, the same components or the like are designated by common reference numerals, and redundant description will be omitted where appropriate. (Example of vehicle configuration)

[0010] Fig. 1 is a plan view of a vehicle 10 to which a driving assistance device 20 according to an embodiment is mounted. The front, rear, left, and right sides of the vehicle 10 in Fig. 1 indicate directions seen from the driver’s seat of the vehicle 10.

[0011] The vehicle 10 of the embodiment may be, for example, an internal combustion car that uses an internal combustion engine as a power source, an electric car, a fuel cell car, or the like that uses an electric motor as a power source, or a hybrid vehicle that uses both as a power source.

[0012] Furthermore, the vehicle 10 can be equipped with various switching devices and can be equipped with devices such as various systems and components required to drive the internal combustion engine or the electric motor. Furthermore, the type, number, arrangement, and the like of devices associated with driving a wheel 13 in the vehicle 10 can be adjusted differently.

[0013] As in Fig. 1, the vehicle 10 includes a vehicle body 12, a plurality of wheels 13, a plurality of distance measuring units 14a to 14l, and a plurality of imaging units 16a to 16d. In a case where it is not necessary to distinguish the distance measuring units 14a to 14l, the distance measuring units are simply referred to as distance measuring unit 14. Additionally, in a case where distinction between the imaging units 16a to 16d is not required, the imaging units are simply referred to as imaging unit 16. The distance measuring units 14a to 14l and the imaging units 16a to 16d are examples of a sensor that detects environmental information of the vehicle 10.

[0014] The vehicle body 12 forms a vehicle interior in which an occupant is located. The plurality of wheels 13, the plurality of distance measuring units 14a to 14l, and the plurality of imaging units 16a to 16d are mounted on the vehicle body. In the example of Fig. 1, the vehicle body 12 comprises four wheels 13, twelve distance measuring units 14 and four imaging units 16. However, the number of distance measuring units 14 and imaging units 16 attached to the vehicle body 12 can be arbitrary.

[0015] The four wheels 13 are mounted at the front, rear, left, and right of the vehicle body 12. For example, the two front wheels 13 function as steered wheels, and the two rear wheels 13 function as driven wheels.

[0016] The distance measuring unit 14 is, for example, a sonar provided on the outer periphery of the vehicle 10 to emit a sound wave, such as an ultrasonic wave, as a detection wave and detect the detection wave reflected from an object, such as an obstacle, in the surroundings of the vehicle 10. Note that the distance measuring unit 14 may be a radar that emits a detection wave, such as a laser light, a millimeter-wave radar, or the like.

[0017] The distance measuring unit 14 collects environmental information indicating a situation around the vehicle 10 and outputs the environmental information to the driving assistance device 20. For example, the distance measuring unit 14 collects a response time, which is a time from the transmission to the reception of a detection wave, as environmental information to specify a distance between an object and the vehicle 10. The driving assistance device 20 can detect the presence or absence of an obstacle or the like around the vehicle 10 and a distance to the obstacle based on the environmental information acquired by the distance measuring unit 14.

[0018] In a case where the detection unit 14 receives a plurality of detection waves reflected from a plurality of points of an object in response to transmission of a detection wave, only the response time of an earliest received detection wave may be included in the environmental information.

[0019] The distance measuring units 14a to 14d are mounted on the front side of the vehicle body 12. Of the distance measuring units 14a to 14d, the distance measuring units 14b and 14c are also called front sonars and are mounted on the front side of the vehicle 10. The distance measuring units 14b and 14c detect an object in front of the vehicle 10 to collect environmental information in front of the vehicle 10. Furthermore, the distance measuring units 14a and 14d are also called corner sonars and are mounted on the corner portions of the front part of the vehicle 10. The distance measuring units 14a and 14d detect an object on the front outside of the vehicle 10 to collect environmental information on the front outside of the vehicle 10.

[0020] The distance measuring units 14e to 14h are mounted on the rear of the vehicle body 12. Of the distance measuring units 14e to 14h, the distance measuring units 14f and 14g are also called rear sonars and are mounted on the rear end of the vehicle 10. The distance measuring units 14f and 14g detect an object behind the vehicle 10 to collect environmental information behind the vehicle 10. Furthermore, the distance measuring units 14e and 14h are also called corner sonars and are mounted on the corner portions of the vehicle rear 10. The distance measuring units 14e and 14h detect an object on the rear outside of the vehicle 10 to collect environmental information on the rear outside of the vehicle 10.

[0021] The distance measuring units 14i to 14l are also referred to as side sonars and are mounted on the sides of the vehicle body 12. Of the distance measuring units 14i to 14l, the distance measuring units 14i and 14j are mounted on the front sides of the vehicle 10. The distance measuring units 14k and 14l are located on the rear sides of the vehicle 10. The distance measuring units 14i to 14l detect an object on the sides of the vehicle 10 to collect environmental information on the sides of the vehicle 10.

[0022] The imaging unit 16 is, for example, a digital camera with an imaging element such as a charge-coupled device (CCD) or a CMOS image sensor (CIS). The imaging unit 16 generates a captured moving image comprising a plurality of individual images or frames captured at a predetermined frame rate, or a captured still image.

[0023] The imaging unit 16 is mounted on the outer periphery of the vehicle body 12. Each imaging unit 16 includes a wide-angle lens or a fisheye lens and can capture an image in a horizontal range of, for example, 140° to 190°. The optical axis of the imaging unit 16 is oriented obliquely downward.

[0024] As a result, the imaging unit 16 collects the environmental information obtained by imaging the surroundings of the vehicle 10, including a road surface, and outputs the environmental information to the driving assistance device 20. The driving assistance device 20 can detect the presence or absence of an obstacle or the like in the surroundings of the vehicle 10, as well as the position of the obstacle, based on the environmental information collected by the imaging unit 16. Furthermore, the driving assistance device 20 can detect a parking space around the vehicle 10 and the position of the parking space based on the environmental information acquired by the imaging unit 16.

[0025] The imaging unit 16c is arranged at a longitudinal center portion of the left end of the vehicle body 12, for example, at the bottom of a left side mirror. The imaging unit 16c collects, as surrounding information, a captured image obtained by imaging an area around the lower left side of the vehicle 10. The imaging unit 16d is arranged at a longitudinal center portion of the right end of the vehicle body 12, for example, at the bottom of a right side mirror. The imaging unit 16d collects, as surrounding information, a captured image obtained by imaging an area around the lower right side of the vehicle 10.

[0026] The imaging unit 16a is mounted at a transverse center portion of the front end of the vehicle body 12, for example, at a front bumper. The imaging unit 16a collects, as surrounding information, a captured image obtained by capturing an area around the front of the vehicle 10. The imaging unit 16b is mounted at a transverse center portion of the rear end of the vehicle body 12, for example, at a rear bumper. The imaging unit 16b collects, as surrounding information, a captured image obtained by capturing an area around the rear of the vehicle 10. (Configuration example of driving support system)

[0027] Fig. 2 is a block diagram showing an example of the overall configuration of a driving assistance system 200 according to the embodiment. The driving assistance system 200 is mounted on, for example, the vehicle 10 and performs driving assistance such as parking into or exiting a parking space of the vehicle 10.

[0028] As in Fig. 2, the driving support system 200 comprises the driving support device 20, a monitor device 30, a braking system 40, an acceleration system 50, a steering system 60, a switching system 70, a vehicle speed sensor 83, the distance measuring unit 14, and the imaging unit 16. These components are interconnected such that they can send and receive information to and from each other via an on-board network NT.

[0029] The on-board network NT includes, for example, a controller area network (CAN) and a local interconnect network (LIN). The on-board network NT may be included in a portion of the driving support system 200.

[0030] The driving assistance device 20 is configured as a microcomputer, e.g., an electronic control unit (ECU), and performs the driving assistance of the vehicle 10.

[0031] The driving assistance device 20 includes a central processing unit (CPU) 21, a display control circuit 23, a solid-state drive (SSD) 24, a read-only memory (ROM) 25, and a random access memory (RAM) 26. The CPU 21, the ROM 25, and the RAM 26 may be integrated into the same housing.

[0032] The CPU 21 is an example of a hardware processor that reads a program stored in a non-volatile device such as the ROM 25 and performs various calculation processing and control according to the program.

[0033] The ROM 25 stores various programs, parameters required for program execution, and the like. The RAM 26 temporarily stores various data used in calculations by the CPU 21. The SSD 24 is a rewritable, non-volatile storage device that retains data when the driving assistance device 20 is turned off.

[0034] Among the calculation processing performed by the driving support device 20, the display control circuit 23 mainly performs image processing of an image obtained from the imaging unit 16, data conversion of an image for display to be displayed on a display unit 31 included in the monitor device 30 (which will be described later), and the like.

[0035] The braking system 40 includes a braking unit 41, a braking control unit 42 and a braking unit sensor 43 and controls the deceleration of the vehicle 10.

[0036] The brake unit 41 is a device that includes, for example, a brake and a brake pedal, and brakes or decelerates the vehicle 10. The brake control unit 42 is, for example, a microcomputer that includes a hardware processor such as a CPU. The brake control unit 42 controls the brake unit 41 based on an instruction from the driving support device 20 to control the deceleration of the vehicle 10. The brake unit sensor 43 is, for example, a position sensor and detects the position of the brake pedal included in the brake unit 41. The brake unit sensor 43 outputs the detected brake pedal position to the on-board network NT.

[0037] The acceleration system 50 includes an acceleration control unit 51, an acceleration control unit 52, and an acceleration unit sensor 53, and controls an acceleration of the vehicle 10.

[0038] The acceleration unit 51 is a device including, for example, an accelerator pedal, and accelerates the vehicle 10. The acceleration control unit 52 is, for example, a microcomputer including a hardware processor such as a CPU. The acceleration control unit 52 controls the acceleration unit 51 based on an instruction from the driving support device 20 to control the acceleration of the vehicle 10. The acceleration unit sensor 53 is, for example, a position sensor and detects the position of the accelerator pedal included in the acceleration unit 51. The acceleration unit sensor 53 outputs the detected accelerator pedal position to the on-board network NT.

[0039] The steering system 60 includes a steering unit 61, a steering control unit 62 and a steering unit sensor 63 and controls a direction of travel of the vehicle 10.

[0040] The steering unit 61 is a device that includes, for example, a steering wheel and steers the traveling direction of the vehicle 10 by turning the steered wheels of the vehicle 10. The steering control unit 62 is, for example, a microcomputer that includes a hardware processor such as a CPU. The steering control unit 62 controls the steering unit 61 based on an instruction from the driving support device 20 to control the traveling direction of the vehicle 10. The steering unit sensor 63 is, for example, an angle sensor that includes a Hall element and detects a steering angle, which is a rotation angle of the steering unit 61. The steering unit sensor 63 outputs the detected steering angle of the steering unit 61 to the on-board network NT.

[0041] The switching system 70 includes a switching unit 71, a switching control unit 72, and a switching unit sensor 73, and controls a switching ratio of the vehicle 10.

[0042] The switching unit 71 is a device that includes, for example, a shift lever, and changes the shift ratio of the vehicle 10. The shift control unit 72 is, for example, a microcomputer that includes a hardware processor such as a CPU. The shift control unit 72 controls the switching unit 71 based on an instruction from the driving support device 20 to control the shift ratio of the vehicle 10. The switching unit sensor 73 is, for example, a position sensor and detects the position of the shift lever included in the switching unit 71. The switching unit sensor 73 outputs the detected shift lever position to the on-board network NT.

[0043] The vehicle speed sensor 83 includes, for example, a Hall element provided near the wheel 13 of the vehicle 10, and detects a rotation amount or rotation speed of the wheel 13 per unit time. The vehicle speed sensor 83 outputs a wheel speed pulse number indicating the detected rotation amount or rotation speed to the on-board network NT as a sensor value for calculating the speed (vehicle speed) of the vehicle 10. The driving support device 20 can calculate the speed, movement amount, and the like of the vehicle 10 based on the sensor value acquired from the vehicle speed sensor 83.

[0044] The monitor device 30 is provided on a dashboard or the like in the vehicle interior of the vehicle 10 and includes the display unit 31 and an input unit 32.

[0045] The display unit 31 is a device such as a liquid crystal display (LCD) or an organic electroluminescent display (OELD). The display unit 31 displays, for example, an image based on image data transmitted from the driving support device 20 and an image for receiving an operation instruction instructing switching between automatic and manual driving.

[0046] The input unit 32 is, for example, a touch panel provided on a screen of the display unit 31. The input unit 32 is configured to enable the transmission of content displayed on the screen by the display unit 31. As a result, the input unit 32 enables an occupant to visually recognize the display content of the display unit 31.

[0047] The input unit 32 receives an instruction input by the occupant touching a position corresponding to the display contents of the display unit 31, and transmits the instruction to the driving support device 20 via the on-board network NT. Note that the input unit 32 is not limited to the touch panel, but may also be a push button switch or the like.

[0048] Fig. 3 is a block diagram showing an example of a functional configuration of the driving support device 20 according to the embodiment. As shown in Fig. 3, the driving assistance device 20 includes a display control unit 201, an acquisition unit 202, a detection unit 203, a route calculation unit 204, a switching unit 205, a movement control unit 206, and a storage unit 207 as functional units.

[0049] These functional units are realized, for example, by the above-described CPU 21 reading and executing a program stored in a device such as the ROM 25. Alternatively, these functional units are realized by the display control circuit 23, the SSD 24, the ROM 25, the RAM 26, and the like, which operate according to the program under the control of the CPU 21.

[0050] It should be noted that some or all of these functional units may be configured by hardware, e.g., by a circuit comprising an application-specific integrated circuit (ASIC).

[0051] The display control unit 201 generates content to be displayed on the display unit 31 of the monitor device 30 and causes the display unit 31 to display the content. That is, the display control unit 201 causes the display unit 31 to display, for example, a notification screen indicating that a parking space in which the vehicle 10 can be parked has been detected, a selection screen for starting, pausing, or canceling the driving assistance, or an environmental image of the vehicle 10 during the driving assistance.

[0052] The acquisition unit 202 acquires, as the surroundings information of the vehicle 10, the transmission / reception information of a sound wave from the distance measuring unit 14 and a captured image of the surroundings of the vehicle 10 from the imaging unit 16.

[0053] The detection unit 203 detects an obstacle, a parking section, a parking space and the like around the vehicle 10 based on the environmental information acquired by the acquisition unit 202.

[0054] The obstacle can be various objects, such as another vehicle, a wall, a pillar, a fence, a ledge, a step, or a wheel stop. The obstacle can also be a person or something similar walking in a parking lot.

[0055] The parking section is intended for parking the vehicle 10 and is an area divided by, for example, a dividing line, a frame line, a straight line, a band, or a step. The parking space is a parking section in which the vehicle 10 can be parked, that is, a parking section in which there is no obstacle, such as another vehicle, to the parking of the vehicle 10. The dividing line, frame line, straight line, band, step, or the like as described above is an example of an object indicating the parking space, and becomes a target used when the driving assistance device 20 causes the vehicle 10 to enter or exit the parking space, in assisting the vehicle 10 to enter or exit the parking space.

[0056] Upon receiving an instruction to start driving assistance from a driver or the like of the vehicle 10, the detection unit 203 detects, for example, the presence or absence of an obstacle, a distance between the vehicle 10 and the obstacle, and the like based on a detection result of the detection unit 14. Furthermore, the detection unit 203 detects the presence or absence of an obstacle, a parking section, the positions (orientations) of the obstacle and the parking section with respect to the vehicle 10, and the shapes, sizes, heights, and the like of the obstacle and the parking section through image processing based on an image acquired by, for example, the imaging unit 16.

[0057] By combining these detection results, the detection unit 203 extracts information about whether or not there is an obstacle around the vehicle 10, whether or not the obstacle can hinder the travel of the vehicle 10, whether or not there is a parking section around the vehicle 10, whether or not it is possible to park the vehicle 10 in the parking section, that is, whether or not the parking section can be used as a parking space, or the like.

[0058] The route calculation unit 204 calculates a target position to which the vehicle 10 is to be guided based on the detection result of the detection unit 203 and calculates a movement route along which the vehicle 10 is to be moved to the target position.

[0059] When the vehicle 10 is parking, the target position is a parking space detected by the detection unit 203. When the vehicle 10 is exiting, the target position is a predetermined location from which the vehicle 10 can safely depart, such as a path provided between several parking sections.

[0060] Furthermore, the route calculation unit 204 can calculate a steering wheel reversal position if necessary. In a case where it is difficult to park or exit the vehicle 10 by only moving backward or forward, one or more steering wheel reversal positions are set.

[0061] The route calculation unit 204 calculates the movement route of the vehicle 10 from the current position of the vehicle 10 to the target position calculated as described above, in order to guide the vehicle 10 to the target position. The movement route may include the steering wheel reversal position, as described above. In this case, the route calculation unit 204 calculates the movement route from the current position of the vehicle 10 to the target position via the steering wheel reversal position.

[0062] In this way, the route calculation unit 204 calculates the movement route for parking, e.g., reversing into a parking space or forward parking. Furthermore, the route calculation unit 204 calculates the movement route for exiting a parking space, e.g., reversing out of a parking space or forward exit of a parking space.

[0063] The motion control unit 206 controls each unit of the vehicle 10 to move the vehicle 10 during driving assistance of the vehicle 10. Specifically, the motion control unit 206 controls all or part of the braking system 40, the accelerator system 50, the steering system 60, and the shifting system 70 to move the vehicle 10 to the target position according to the above movement route. At this time, the motion control unit 206 moves the vehicle 10 while receiving feedback from the respective sensors such as the braking unit sensor 43, the accelerator unit sensor 53, the steering unit sensor 63, the shifting unit sensor 73, and the vehicle speed sensor 83.

[0064] Note that the detection unit 203 continues to acquire the surrounding information from the distance measuring unit 14 and the imaging unit 16 even after the motion control unit 206 has started the movement of the vehicle 10. The route calculation unit 204 described above appropriately recalculates the movement route based on the detection result of the detection unit 203. After the movement route is recalculated, the motion control unit 206 continues the movement of the vehicle 10 to finely adjust the position of the vehicle 10 accordingly.

[0065] When the motion control unit 206 controls the vehicle 10, the switching unit 205 switches acceleration limits as an upper limit of the acceleration of the vehicle 10 as needed. For example, a default value set when the driving assistance is started and a switching value applied when a steering angle of the vehicle 10 becomes equal to or greater than a predetermined threshold in a state where the vehicle 10 is stopped are provided as the acceleration limits during driving assistance.

[0066] For example, the storage unit 207 stores these acceleration limit values. The switching unit 205 switches these acceleration limit values ​​with reference to the storage unit 207 under a predetermined condition.

[0067] The motion control unit 206 described above sets a target speed according to a current situation of the vehicle 10, accelerates the vehicle 10 with an acceleration within the acceleration limit value determined by the switching unit 205, and controls the speed of the vehicle 10 to the target speed.

[0068] The storage unit 207 stores, for example, a program executed by the CPU 21 of the driving assistance device 20 and various control parameters necessary for the operation of the driving assistance device 20. As described above, the storage unit 207 also stores the settings of the above-described various types of acceleration limits or the like, which are the upper limits of the acceleration of the vehicle 10 during driving assistance.

[0069] Fig. Figure 4 shows an example of setting the acceleration limits described above. Fig. 4 is a diagram illustrating an example of the acceleration limit value settings maintained by the driving support device 20 according to the embodiment. In the diagram of Fig. 4 the horizontal axis represents time (s) and the vertical axis represents the target speed (m / s).

[0070] As in Fig. As shown in Figure 4, among the acceleration limits maintained by the driving support device 20, a switching value LVe applied under the predetermined condition described above is set to a value smaller than a standard value LVd set at normal times. Therefore, for example, at the same target speed of the vehicle 10, it takes longer to reach the target speed when the switching value LVe is applied than when the standard value LVd is set.

[0071] The above-described condition in which the steering wheel or the like is operated in a state where the vehicle 10 is stopped and the steering angle becomes equal to or greater than the predetermined threshold is a condition called static steering. In the static steering condition, the vehicle 10 is likely to be shaken when starting to move.

[0072] During driving assistance, the vehicle 10 is controlled while generally avoiding the static steering state. However, if, for example, the space around the vehicle 10 is very narrow, control may be performed in the static steering state. When the vehicle 10 is in a static steering state, the switching value LVe, which is smaller than the standard value LVd, is used as the acceleration threshold, thereby preventing such shaking of the vehicle 10.

[0073] As described above, during driving assistance, the vehicle 10 is controlled in a state where only the default value LVd is set. Such a default value LVd may also be referred to as the initial acceleration limit or the default acceleration limit. On the other hand, in the present specification, the switching value LVe applied when the vehicle 10 is in a static steering state may also be referred to as the acceleration limit during static steering.

[0074] Among these acceleration limits, the default value LVd is an example of a first acceleration limit, and the switching value LVe is an example of a second acceleration limit. (Processing example of a driving assistance device)

[0075] Hereinafter, an example of a driving support operation by the driving support device 20 of the embodiment will be described with reference to Fig. 5 described. Fig. 5 is a flowchart illustrating a process example of the driving support process by the driving support device 20 according to the embodiment.

[0076] As in Fig. As shown in Figure 5, the driving assistance device 20 begins control when an instruction to start driving assistance is received from a driver or the like of the vehicle 10 (step S101). The route calculation unit 204 calculates the movement route from the stop position to the target position of the vehicle 10 at the current time (step S102). When the driving assistance starts, the switching unit 205 sets the default value LVd as the acceleration threshold value (step S103).

[0077] In addition, the switching unit 205 determines, for example, based on the detection result of the vehicle speed sensor 83 (see Fig. 2) whether the vehicle 10 is in the stopped state or not (step S104). If the vehicle 10 is in the stopped state (step S104: Yes), the switching unit 205 determines, for example, based on the detection result of the steering unit sensor 63 (see Fig. 2) whether the steering angle of the vehicle 10 is equal to or greater than the predetermined threshold value or not (step S105).

[0078] If the steering angle is equal to or greater than the predetermined threshold value (step S105: Yes), the switching unit 205 switches the acceleration limit value of the vehicle 10 from the standard value LVd set in the processing of step 103 at the beginning of the start of the driving assistance to the switching value LVe (step S106).

[0079] When the switching value LVe is set as the acceleration threshold, the motion control unit 206 accelerates the vehicle 10 to the target speed at an acceleration within the switching value LVe and performs the motion control of the vehicle 10 according to the calculated movement route (step S107).

[0080] When the motion control of the vehicle 10 is started, the switching unit 205 determines whether the steering angle falls below the predetermined value (step S109). As long as the steering angle remains at or above the predetermined threshold (step S109: No), the switching unit 205 continues monitoring the steering angle.

[0081] When the steering wheel or the like is operated in the stopped state and the vehicle 10, whose steering angle is equal to or greater than the predetermined threshold, starts moving, the static steering state is canceled and the steering angle becomes smaller than the predetermined threshold. Therefore, if the steering angle is smaller than the predetermined value (step S109: Yes), the switching unit 205 resets the acceleration limit setting to the original default value LVd (step S110). That is, the acceleration limit in the static steering state is canceled through the processing of step S110.

[0082] In a case where the vehicle 10 is not in the stopped state (step S104: No) or the steering angle is smaller than the predetermined threshold (step S105: No), the processing of step S106 is not performed, and the originally set standard value LVd is maintained as the acceleration threshold value.

[0083] The motion control unit 206 accelerates the vehicle 10 to the target speed at an acceleration within the standard value LVd and performs the motion control of the vehicle 10 according to the calculated motion control route (step S108).

[0084] Furthermore, the motion control unit 206 determines whether the driving assistance process is completed with the vehicle 10 reaching the target position or the like (step S111). If the driving assistance continues (step S111: No), the processing from step S104 is repeated until the driving assistance is completed (step S111: Yes).

[0085] The driving support process by the driving support device 20 of the embodiment ends in this way. (Overview)

[0086] The driving assistance device performs driving assistance of the vehicle based on the vehicle surroundings information from various sensors such as the distance measuring unit and the imaging unit. At this time, for example, in a case where there is a very narrow parking space, control may be performed to start the vehicle 10 in a static steering state. However, if the vehicle 10 is started in a static steering state, it is likely to shake, and a passenger of the vehicle, including a driver, may feel uncomfortable.

[0087] According to the driving assistance device 20 of the embodiment, in a case where the vehicle 10 is stopped and the steering angle of the vehicle 10 is equal to or greater than the predetermined threshold during control of the vehicle 10 by the motion control unit 206, the acceleration threshold value, which is the upper limit of the acceleration of the vehicle 10, is set to the switching value LVe. This makes it possible to suppress the shaking of the vehicle 10 when the vehicle 10 starts moving in a static steering state and improve the ride comfort of the occupants of the vehicle 10, including the driver.

[0088] According to the driving assistance device 20 of the embodiment, when starting the driving assistance, the acceleration limit value of the vehicle 10 is set to the default value LVd. Thus, the default value LVd, which has a larger value than the switching value LVe, is provided separately from the switching value LVe, making it possible to force the vehicle 10 to reach the target speed with appropriate acceleration, reducing the unnecessary time required for parking or exiting the parking space and quickly completing the process.

[0089] According to the driving assistance device 20 of the embodiment, the acceleration threshold value is switched to the default value LVd when the steering angle becomes smaller than the above threshold value after the acceleration threshold value of the vehicle 10 is set to the switching value LVe. Thus, the switching value LVe with a value smaller than the default value LVd is applied only while the vehicle 10 is in a static steering state, making it possible to reduce unnecessary time for parking or reversing, while improving the occupant's driving comfort and quickly completing the process.

[0090] In the above embodiment, the driving assistance device 20 is mounted on the vehicle 10. However, the driving assistance device 20 does not necessarily have to be mounted on the vehicle 10. For example, the driving assistance device may acquire the vehicle's surrounding information from various sensors located remotely from the vehicle and perform driving assistance of the vehicle remotely. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] WO 2020 / 066 331 A [0003, 0004] JP 5 257 647 B2 [0003, 0004]

Claims

[1] A driving assistance device (20) that performs driving assistance of a vehicle (10) based on environmental information collected by a plurality of sensors (14a to 14l, 16a to 16d) provided in the vehicle (10), the driving assistance device (20) comprising: a route calculation unit (204) configured to calculate a movement route of the vehicle (10) to a target position based on the environmental information from the plurality of sensors (14a to 14l, 16a to 16d); a switching unit (205) configured to switch settings of an upper limit value of an acceleration of the vehicle (10) between a first acceleration limit value (LVd) and a second acceleration limit value (LVe) that is smaller than the first acceleration limit value (LVd); and a movement control unit (206) configured to move the vehicle (10) along the movement route while controlling the vehicle (10) with an acceleration within the upper limit value set by the switching unit (205), wherein the switching unit (205) sets the upper limit value of the acceleration of the vehicle (10) to the second acceleration limit value (LVe) in a case where the vehicle (10) is stopped and a steering angle of the vehicle (10) during control of the vehicle (10) by the motion control unit (206) is equal to or greater than a predetermined threshold value. [2] The driving support device (20) according to claim 1, wherein the switching unit (205) sets the upper limit value of the acceleration of the vehicle (10) to the first acceleration limit value (LVd) when the driving assistance is started. [3] The driving support device (20) according to claim 1 or 2, wherein the switching unit (205) switches the upper limit value of the acceleration of the vehicle (10) to the first acceleration limit value (LVd) when the steering angle becomes smaller than the threshold value after the upper limit value of the acceleration of the vehicle (10) is set to the second acceleration limit value (LVe).

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