VEHICLE CONTROL DEVICE

Abstract

A vehicle control device is provided that stops a vehicle at a desired stopping position without requiring frequent use of the accelerator pedal on an incline. The vehicle control device controls a propulsion device of the vehicle based on the amount of actuation of an actuating element and comprises: an actuation amount detection unit that detects the amount of actuation; a gradient detection unit that detects the gradient of a road surface on which the vehicle is traveling; and a control unit that controls the propulsion device so that the vehicle comes to a stop at a reference stopping distance when the gradient is uphill and the actuation amount of the propulsion device becomes zero during travel.

Description

Technical field

[0001] The present disclosure relates to a vehicle control device. State of the art

[0002] When the driver releases the accelerator pedal while driving, the vehicle coasts in neutral and gradually decelerates to a standstill. This occurs because the fuel supply is cut off if the propulsion device is an internal combustion engine, or the electrical supply is switched off if the propulsion device is an electric motor. If the driver needs to stop the vehicle before a target stopping position—for example, due to a stationary vehicle or a red traffic sign (traffic light) ahead—the driver releases the accelerator pedal at a certain distance before the target stopping position and allows the vehicle to coast until it comes to a complete stop. Cited documents Patent literature

[0003] PTL 1 Japanese patent application Publication No. 2020-152279 Summary of the invention: Technical problem

[0004] When coasting to a stop position while driving uphill, the following problem occurs: If the driver releases the accelerator pedal at a certain distance before the stop position in the same way as on a level road, the deceleration (negative acceleration) on the incline is greater than on level ground, causing the vehicle to come to a complete stop before reaching the stop position. Therefore, when driving uphill, the driver must frequently press the accelerator pedal by placing the foot that was just released back on the pedal and depressing it to accelerate through the drive system, thus bringing the vehicle to a stop at the stop position.

[0005] It is therefore an objective of the present disclosure to provide a vehicle control device with which the vehicle can be stopped at the point where it is to stop, without the driver having to frequently operate the accelerator pedal on an incline. Solution to the problem

[0006] A vehicle control device according to the present disclosure is a vehicle control device that controls a propulsion device of a vehicle depending on an actuation amount of an actuating element, wherein the vehicle control device comprises: an actuation amount detection unit that detects the actuation amount; a gradient detection unit that detects a gradient of a road surface on which the vehicle is traveling; and a control unit that controls the propulsion device such that the vehicle comes to a standstill at a reference stopping distance if the gradient is uphill and the actuation amount becomes zero during the travel of the propulsion device.

[0007] Furthermore, a vehicle control device according to the present disclosure relates to a vehicle control device that controls a propulsion device of a vehicle depending on the actuation amount of an actuating element, wherein the vehicle control device comprises: an actuation amount detection unit that detects the actuation amount; a gradient detection unit that detects a gradient of a road surface on which the vehicle is traveling; an environmental situation detection unit that detects an environmental situation of the vehicle; a required stopping distance calculation unit that calculates a required stopping distance based on the environmental situation; and a control unit that controls the propulsion device such that the vehicle comes to a standstill at the required stopping distance if the gradient is uphill and the actuation amount of the propulsion device becomes zero during travel. Advantageous effects of the invention

[0008] According to the vehicle control device as disclosed herein, the vehicle reliably comes to a stop at the position where it is intended to stop, even when driving uphill, so that the driver does not have to frequently operate the accelerator pedal. Brief description of the drawings Fig. Figure 1 is a schematic representation of a vehicle configuration; Fig. 2 is a functional block diagram of a vehicle control device; Fig. 3 is a flowchart showing the operation of the vehicle control device; Fig. Figure 4A shows a diagram with an example of the change over time in the output power of a drive device; and Fig. Figure 4B shows a diagram with an example of a change in vehicle speed over time. Description of the embodiments

[0009] An embodiment of the present disclosure is described below with reference to the drawings. It should be noted that the embodiment described below represents a specific example of the present disclosure. Therefore, the components shown in the embodiment, their arrangement positions, connection types, and the like serve only for illustrative purposes and do not limit the spirit of the present disclosure. Furthermore, components not mentioned in the independent claims are presented in the following description as optional components.

[0010] Furthermore, the drawings are schematic representations and not necessarily to scale. Essentially identical configurations are designated by the same reference symbols in the drawings, and redundant descriptions may be omitted or simplified.

[0011] Fig. Figure 1 shows a schematic diagram of a vehicle configuration with a vehicle control device according to the present disclosure. The vehicle 100 comprises: a drive device 2 that propels the vehicle 100; an accelerator pedal 3, which is used by the driver to actuate the drive device 2; a brake 4; a sensing device 5, which includes various sensors; a storage device 6; and a vehicle control device 1, which controls the drive device 2 and the brake 4.

[0012] The vehicle control device 1 is a computer with a general configuration, comprising a processor, memory, communication device, user interface and the like.

[0013] The drive device 2 is, for example, a hybrid drive device comprising an internal combustion engine 21 and an electric motor 22, but can also have only the internal combustion engine 21 or only the electric motor 22.

[0014] The accelerator pedal 3 is a conventional accelerator pedal operated by the driver's foot and corresponds to the actuating element as defined in this disclosure. Fuel is supplied to the internal combustion engine 21 or electrical energy to the electric motor 22 according to the amount of actuation (the pedal travel) of the accelerator pedal 3, and the driving force of the drive device 2 is transmitted to the wheels (not shown). When the foot is removed from the accelerator pedal 3, the fuel or electrical supply is interrupted, and the driving force of the drive device 2 becomes zero.

[0015] Brake 4 is a conventional braking device that decelerates the vehicle by 100, for example a disc brake or a regenerative brake.

[0016] The brake 4 generates a braking force corresponding to the degree of actuation of a (not shown) brake pedal. Furthermore, the brake 4 is actuated by the vehicle control unit 1 to exert the braking force.

[0017] The detection device 5 comprises: an actuation amount detection sensor 51, which detects the actuation amount of the accelerator pedal 3; a vehicle weight sensor 52, which detects the weight of the vehicle 100; a speed sensor 53, which detects the speed of the vehicle 100; a gradient sensor 54, which detects the gradient of a road surface on which the vehicle 100 is traveling; an environmental situation detection sensor 55, which detects an environmental situation of the vehicle 100; and a position sensor 56, which detects the position of the vehicle 100, for example, a GPS or the like. The environmental situation detection sensor 55 is, for example, an obstacle sensor such as an ultrasonic sensor or radar, which detects an obstacle in front of the vehicle, or an image capture device, which detects a traffic light, a traffic sign, or the like in front of the vehicle.

[0018] The storage device 6, for example, is a general memory or the like and stores information such as a gradient map 61—a road map with elevation or gradient information—and a reference stopping distance table 62, which contains a table, classified by vehicle weight and speed, of the distances required for the vehicle to come to a complete stop on a level road surface while idling. With the gradient map 61, the gradient of the road surface can be determined while driving if the current position and direction of travel of the vehicle 100 are known. The reference stopping distance table 62 is created in advance, for example, by experimentally measuring the reference stopping distance for different vehicle weights and speeds."Coasting" here refers to the state in which the vehicle travels due to its inertia after the driver has taken their foot off the accelerator pedal while driving, and includes both the state in which the clutch is engaged or disengaged in a combustion engine-powered vehicle, and the state in which the clutch is engaged or disengaged in an electric vehicle, or in which a recuperation brake is active or inactive.

[0019] Fig. Figure 2 is a functional block diagram of the vehicle control unit 1. Each functional unit designated "XX unit" (or "-section") corresponds to a function that is implemented by the processor of the vehicle control unit 1 when the control program is executed. The actuation amount detection unit 11 detects the actuation amount of the accelerator pedal 3 using the actuation amount detection sensor 51. The actuation amount is, for example, information about the rotation angle or the displacement of the accelerator pedal 3.

[0020] The gradient detection unit 12 detects the gradient of the road surface on which the vehicle 100 is traveling, using the gradient sensor 54 or the gradient map 61. The gradient is, for example, information about the angle of inclination of the road surface.

[0021] The weight detection unit 13 detects the total weight of the vehicle 100 using the vehicle weight sensor 52. The total weight can be detected before the start of the journey or during the journey.

[0022] The speed detection unit 14 detects the vehicle speed 100 using the speed sensor 53. The vehicle speed is measured, for example, in kilometers per hour or meters per second.

[0023] The environmental situation detection unit 15 detects the environmental situation of the vehicle 100 using the environmental situation detection sensor 55. The environmental situation of the vehicle 100 refers to conditions that may be related to the vehicle 100 stopping, for example, the presence or absence of a stationary vehicle in front of the vehicle 100, the presence or absence of a pedestrian in front of the vehicle 100, a traffic light and its light color in front of the vehicle 100, the content of a traffic sign such as "Stop" in front of the vehicle 100, as well as the presence or absence of a pedestrian crossing and a person crossing it in front of the vehicle 100.

[0024] The required stopping distance calculation unit 16 calculates a distance to a position where the vehicle 100 should stop, based on the environmental situation detected by the environmental situation detection unit 15. The required stopping distance is, for example, the distance to a predetermined position in front of an obstacle such as a stationary vehicle or a pedestrian, if an obstacle is in front of the vehicle; the distance to the stop line in front of a red traffic light, if a red traffic light is present; or the distance to a position in front of a pedestrian crossing, if a pedestrian is crossing there. In other words, the required stopping distance is the distance to the position where the vehicle must stop.

[0025] The estimated stopping distance calculation unit 17 calculates an estimated stopping distance until the vehicle comes to a standstill while coasting on an incline. The estimated stopping distance can be calculated mechanically from the vehicle's weight, speed, frictional force, and air resistance. Frictional force and air resistance can, for example, be determined experimentally beforehand.

[0026] Based on the information received, the control unit 18 controls the drive device 2 and the brake 4 in such a way that the vehicle 100 continues driving beyond the reference stopping distance or the required stopping distance and then comes to a standstill.

[0027] Next, with reference to the flowchart in Fig. 3 The operation of the processor of the vehicle control device 1 according to the present disclosure (hereinafter referred to simply as the "vehicle control device") is described. The vehicle control device 1 detects the amount of depressurization of the accelerator pedal 3 using the depressurization sensor 51 (step S1). Subsequently, the vehicle control device 1 determines whether the driver has removed their foot from the accelerator pedal 3, based on the amount of depressurization of the accelerator pedal 3 (step S2). Specifically, the vehicle control device 1 determines that the driver has removed their foot from the accelerator pedal 3 when the amount of depressurization of the accelerator pedal 3 changes from a positive value to zero. If it cannot be determined that the driver has removed their foot from the accelerator pedal 3 (step S2: No), the detection of the amount of depressurization of the accelerator pedal 3 is repeated.

[0028] When the driver has taken their foot off the accelerator pedal 3 (step S2: Yes), the vehicle control unit 1 detects the vehicle weight, speed, and road gradient using the vehicle weight sensor 52, the speed sensor 53, and the gradient sensor 54, respectively (step S3). The road gradient can also be obtained from the gradient map 61 instead of being detected by the gradient sensor 54.

[0029] Next, the vehicle control unit 1 determines whether the vehicle 100 is on an incline, based on the detected road gradient (step S4). Specifically, the vehicle control unit 1 determines that the vehicle 100 is on an incline if the road gradient is positive. If the vehicle is not on an incline (step S4: No), the process is terminated.

[0030] If the vehicle is on an incline (step S4: Yes), the stopping distance corresponding to the current vehicle weight and speed is retrieved from the reference stopping distance table 62 stored in the memory device 6 (step S5). If no stopping distance is available for the current vehicle weight and speed, the stopping distance for a similar weight and speed can be used.

[0031] The vehicle control unit 1 then acquires information about the vehicle 100's surroundings using the environmental situation detection sensor 55 (step S6). The required stopping distance – i.e., the distance at which the vehicle 100 should stop – is then calculated based on this information (step S7). The vehicle control unit 1 then calculates the estimated stopping distance (step S8).

[0032] The vehicle control unit 1 then determines whether the required stopping distance is longer than the reference stopping distance (step S9). If the required stopping distance is longer than the reference stopping distance (step S9: Yes), the vehicle control unit 1 performs an assistance control of the drive unit 2, causing the vehicle to travel 100° beyond the reference stopping distance and then stop (step S10). The assistance control consists of controlling the drive unit 2 so that the vehicle does not stop on the incline before reaching the reference stopping distance, but is assisted until it has covered the reference stopping distance and then comes to a standstill. The required assistance power can be calculated as the output power for advancing the vehicle from the difference between the reference stopping distance and the estimated stopping distance, in order to stop the vehicle upon reaching this distance.When performing the assistance control, the vehicle control device 1 can either drive the internal combustion engine 21 or the electric motor 22; however, preferably the electric motor 22 is operated in order to reduce fuel consumption and exhaust emissions.

[0033] On the other hand, if the required stopping distance is equal to or less than the reference stopping distance (step S9: No), the vehicle control device 1 determines whether the required stopping distance is shorter than the estimated stopping distance (step S11). If the required stopping distance is shorter than the estimated stopping distance (step S11: Yes), the vehicle control device 1 performs a braking control of the brake 4 so that the vehicle travels 100° beyond the required stopping distance and then comes to a stop (step S12). The braking control consists of controlling the brake 4 so that the vehicle travels beyond the required stopping distance on the incline and then comes to a standstill.The required braking force can be calculated as the braking force required to stop the vehicle at a distance shorter than the estimated stopping distance, corresponding to the difference between the estimated stopping distance and the required stopping distance.

[0034] If the required stopping distance is equal to or greater than the estimated stopping distance (step S11: No), the vehicle control device 1 performs an assistance control such that the vehicle drives 100% beyond the required stopping distance and then stops (step S13).

[0035] The assistance control consists of controlling the drive device 2 in such a way that the vehicle 100 does not stop on the incline before covering the required stopping distance, but rather the journey is supported in such a way that the vehicle 100 travels beyond the required stopping distance and then comes to a standstill.

[0036] The required support power can be calculated as the output power needed to move the vehicle forward and then stop it, based on the difference between the required stopping distance and the estimated stopping distance.

[0037] Fig. 4A and Fig. Figure 4B shows an example of diagrams illustrating the change over time in the output power of the drive device 2 ( Fig. 4A) and the change in speed over time ( Fig. 4B) in a case in which the vehicle control device 1 operates according to the present disclosure and the vehicle 100 travels on an incline by coasting past the reference stopping distance and then comes to a stop. In Fig. 4A drives vehicle 100 to time t1 with a predetermined output power w0 of the drive unit 2. When the driver takes their foot off the accelerator pedal 3 at t1, the output power of the drive unit 2 decreases, but the vehicle operates with an output power w1, which is lower than w0, to perform the assistance control. When vehicle 100 has covered the reference stopping distance and comes to a stop at t2, the output power of the drive unit 2 becomes zero.

[0038] In Fig.4B drives vehicle 100 at a predetermined speed v0 until time t1. When the driver takes their foot off the accelerator pedal 3 at t1, the speed decreases in the same way as when coasting on a level road (curve g0). Then, at t2, the vehicle's speed 100 becomes zero, and the vehicle comes to a standstill. In this case, as shown by the dashed line g0', the vehicle can stop before t2 as long as the error is less than or equal to a predetermined tolerance value d. This means that the vehicle can also stop before reaching the required stopping distance. Curve g1 shows the state when the vehicle control device 1 does not perform any assistance control and decelerates the vehicle while coasting until it reaches the estimated stopping distance and then stops.

[0039] As described above, if the driver takes their foot off the accelerator pedal 3 while driving uphill, the vehicle will exceed the reference stopping distance and then come to a stop. Therefore, the driver can release their foot from the accelerator pedal 3 at a predetermined distance before the target stopping position – with the same feeling as when driving on a level road – and does not need to perform a complicated operation involving first releasing and then re-engaging the accelerator pedal 3. Furthermore, if the required stopping distance is shorter than the reference stopping distance, the drive unit 2 or the brake 4 is controlled so that the vehicle reliably exceeds the required stopping distance and then comes to a stop. Thus, the driver can bring the vehicle to a safe stop simply by taking their foot off the accelerator pedal 3.

[0040] In the embodiment described above, the vehicle is controlled to stop at the reference stopping distance if the required stopping distance is longer than the reference stopping distance. However, the vehicle can also be controlled to exceed the required stopping distance and then stop, regardless of the length of the reference stopping distance or the required stopping distance. That is to say, if the driver takes their foot off the accelerator pedal 3 on an incline, a braking control can be performed if the required stopping distance is shorter than the estimated stopping distance, so that the vehicle stops at the required stopping distance; and if the required stopping distance is equal to or greater than the estimated stopping distance, an assistance control can be performed so that the vehicle stops at the required stopping distance.Accordingly, regardless of when the driver takes their foot off the accelerator pedal, the vehicle travels appropriately beyond the required stopping distance and then comes to a standstill.

[0041] In the embodiment described above, the vehicle is configured to drive beyond the reference stopping distance or the required stopping distance and then come to a stop. However, control by the vehicle control device 1 can be terminated, for example, when the vehicle speed is equal to or less than a predetermined speed, or when the driver applies the brake pedal. This allows the driver to stop the vehicle with greater comfort and less disruption.

[0042] Furthermore, in the embodiment described above, the output power of the drive unit 2 is set to a constant w1 during the assistance control. However, the output power of the drive unit 2 does not have to be constant during the assistance control. That is, the output power does not have to remain constant as long as the vehicle exceeds the reference stopping distance or the required stopping distance and then comes to a stop. For example, the output power can be gradually reduced according to the remaining distance to the reference stopping distance or the required stopping distance. This allows the output power of the drive unit to be reduced as the vehicle speed decreases, so that the driver can stop the vehicle with less discomfort. Industrial applicability

[0043] It is possible to provide a vehicle that comes to a stop on inclines by coasting in a manner that feels natural to the driver. Reference symbol list 1 Vehicle control device 11 Actuation amount recording unit 12 Slope detection units 13 Weight recording unit 14 Speed ​​detection unit 15 Environmental situation detection unit 16 Required stopping distance calculation unit 17 Estimated stopping distance calculation unit 18 Control unit 2 Drive device 21 Internal combustion engine 22 Electric motor 3 Accelerator pedal 4 Brake 5 Detection device 51 Actuation amount detection sensor 52 Vehicle weight sensor 53 Speed ​​sensor 54 Slope sensor 55 Environmental situation detection sensor 56 Position sensor 6 Storage device 61 Gradient map 62 Reference holding distance table 100 vehicles QUOTES INCLUDED IN THE DESCRIPTION

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

[0000] JP 2020-152279

[0003]

Claims

Vehicle control device that controls a vehicle's drive system depending on the actuation amount of an actuating element, wherein the vehicle control device comprises: an actuation amount detection unit that detects the actuation amount; a gradient detection unit that detects a gradient of a road surface on which the vehicle is traveling; and a control unit that controls the drive system such that the vehicle comes to a standstill at a reference stopping distance if the gradient is uphill and the actuation amount becomes zero during the drive system's travel. Vehicle control device according to claim 1, further comprising: a weight detection unit that detects the total weight of the vehicle; and a speed detection unit that detects the speed of the vehicle, wherein the control unit controls the drive device depending on the total weight and the speed. Vehicle control device according to claim 1, further comprising: an environment situation detection unit that detects an environment situation of the vehicle; and a required stopping distance calculation unit that calculates a required stopping distance based on the environment situation, wherein the control unit controls the drive device such that the vehicle comes to a standstill at the required stopping distance if the required stopping distance is shorter than the reference stopping distance. Vehicle control device according to claim 3, further comprising an estimated stopping distance calculation unit that calculates an estimated stopping distance, wherein the control unit controls a braking device instead of the control of the drive device if the required stopping distance is shorter than the estimated stopping distance. A vehicle control device that controls a vehicle's drive system depending on the actuation amount of an actuating element, wherein the vehicle control device comprises: an actuation amount detection unit that detects the actuation amount; a gradient detection unit that detects a gradient of a road surface on which the vehicle is traveling; an environmental situation detection unit that detects an environmental situation of the vehicle; a required stopping distance calculation unit that calculates a required stopping distance based on the environmental situation; and a control unit that controls the drive system such that the vehicle comes to a standstill at the required stopping distance if the gradient is uphill and the actuation amount of the drive system becomes zero during travel. Vehicle control device according to claim 5, further comprising an estimated stopping distance calculation unit that calculates an estimated stopping distance, wherein the control unit controls a braking device instead of the control of the drive device if the required stopping distance is shorter than the estimated stopping distance.

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