Acceleration controller, and acceleration control method

Abstract

To prevent a commercial vehicle from erroneously starting backward.SOLUTION: An acceleration controller 30 has: an acquisition unit 321 for acquiring an opening of an accelerator pedal of a vehicle on which an installation is connectable, a stepping down speed when a driver steps down the accelerator pedal, a weight of the vehicle, and a gradient of a road surface with which the vehicle comes into contact; and a torque control unit 322 for controlling a magnitude of an output torque of a vehicular drive power source on the basis of the opening of the accelerator pedal, the stepping down speed, the weight, and the gradient of the road surface in a direction in which the vehicle backs, when receiving an operation to move the vehicle backward.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an acceleration control device and an acceleration control method. [Background technology]

[0002] The starting control device of Patent Document 1 controls acceleration by driving at least either the engine or the motor based on the weight of commercial vehicles such as buses and trucks, the gradient of the road surface, and the amount of accelerator operation by the driver, thereby reducing fuel consumption when starting and avoiding insufficient traction force. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-95040 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, commercial vehicles with a rear-mounted body cannot be equipped with a sensor or camera for detecting obstacles behind the commercial vehicle, and therefore do not have a function for detecting obstacles behind the commercial vehicle and suppressing erroneous starting when reversing. As a result, there is a problem that commercial vehicles may erroneously start when starting backwards.

[0005] The present invention has been made in consideration of these points, and has an object to prevent commercial vehicles from erroneously starting backwards. [Means for solving the problem]

[0006] An acceleration control device according to a first aspect of the present invention has an acquisition unit that acquires the opening degree of an accelerator pedal equipped on a vehicle to which a body can be connected, the accelerator pedal depression speed when a driver depresses the accelerator pedal, the weight of the vehicle, and the gradient of a road surface on which the vehicle contacts, and a torque control unit that, when an operation to reverse the vehicle is received, controls the magnitude of the output torque of a driving force source equipped on the vehicle based on the accelerator pedal opening degree, the depression speed, the weight, and the gradient of the road surface in the direction in which the vehicle reverses.

[0007] The torque control unit may control the magnitude of the output torque on condition that the opening degree of the accelerator pedal is equal to or greater than a first threshold value and the depression speed is equal to or greater than a second threshold value.

[0008] The torque control unit may control the magnitude of the output torque so that the driving force source generates a torque having a smaller magnitude between an operation torque corresponding to an opening degree of the accelerator pedal and a maximum torque which is a maximum value of the output torque.

[0009] The torque control unit may determine, when the weight is equal to or greater than a third threshold and the gradient in the direction in which the vehicle is reversing is equal to or greater than a fourth threshold, the maximum torque to be a first torque, which is a multiplied value of a maximum value of output torque that the driving force source can generate by a first ratio.

[0010] When the weight is equal to or greater than the third threshold and the gradient in the direction in which the vehicle is reversing is less than the fourth threshold, the torque control unit may determine the maximum torque to be a second torque, which is a multiplied value obtained by multiplying a maximum value of output torque that can be generated by the driving force source by a second rate that is smaller than the first rate.

[0011] When the weight is less than the third threshold and the gradient in the direction in which the vehicle is reversing is equal to or greater than the fourth threshold, the torque control unit may determine the maximum torque to be a second torque, which is a multiplied value obtained by multiplying a maximum value of output torque that can be generated by the driving force source by a second rate that is smaller than the first rate.

[0012] When the weight is less than the third threshold and the gradient in the direction in which the vehicle is reversing is less than the fourth threshold, the torque control unit may determine the maximum torque to be a third torque, which is a multiplied value obtained by multiplying a maximum value of output torque that can be generated by the driving force source by a third ratio that is smaller than the second ratio.

[0013] The torque control unit may determine, when the weight is equal to or greater than a third threshold and the gradient in the direction in which the vehicle is reversing is equal to or greater than a fourth threshold, that the output torque is a first torque that is obtained by reducing the operation torque corresponding to the opening degree of the accelerator pedal by a first percentage.

[0014] The torque control unit may determine, as the output torque, a second torque that is obtained by reducing the operation torque by a second rate that is greater than the first rate, when the weight is equal to or greater than the third threshold value and the gradient in the direction in which the vehicle is reversing is less than the fourth threshold value.

[0015] The torque control unit may determine, as the output torque, a second torque that is obtained by reducing the operation torque by a second rate that is greater than the first rate, when the weight is less than the third threshold value and the gradient in the direction in which the vehicle is reversing is equal to or greater than the fourth threshold value.

[0016] The torque control unit may determine, as the output torque, a third torque that is obtained by reducing the operation torque by a third rate that is greater than the second rate, when the weight is less than the third threshold value and the gradient in the direction in which the vehicle is reversing is less than the fourth threshold value.

[0017] The torque control unit may not control the magnitude of the output torque when the weight is equal to or greater than a third threshold, even if the opening degree of the accelerator pedal is equal to or greater than the first threshold, and the depression speed is equal to or greater than the second threshold.

[0018] The torque control unit may not control the magnitude of the output torque when the weight is less than the third threshold and the gradient in the direction in which the vehicle is reversing is equal to or greater than a fourth threshold, even if the accelerator pedal opening is equal to or greater than the first threshold and the pedaling speed is equal to or greater than the second threshold.

[0019] The torque control unit may determine, when the weight is less than the third threshold value and the gradient in the direction in which the vehicle is reversing is less than a fourth threshold value, as the output torque a fourth torque that is a fourth percentage smaller than the operation torque corresponding to the opening degree of the accelerator pedal.

[0020] An acceleration control method according to a second aspect of the present invention includes an acquisition step executed by a processor to acquire the opening degree of an accelerator pedal equipped on a vehicle to which a body can be connected, the accelerator pedal depression speed when the driver depresses the accelerator pedal, the weight of the vehicle, and the gradient of a road surface on which the vehicle contacts, and a control step to control the magnitude of the output torque of a driving force source equipped on the vehicle based on the accelerator pedal opening degree, the depression speed, the weight, and the gradient of the road surface in the direction in which the vehicle reverses, when an operation to reverse the vehicle is received. Effect of the Invention

[0021] According to the present invention, it is possible to suppress a commercial vehicle from erroneously starting backwards. [Brief description of the drawings]

[0022] [Figure 1] FIG. 2 is a diagram for explaining an overview of a vehicle S according to the present embodiment. [Diagram 2] 1 is a diagram for explaining a gradient in a direction in which a vehicle S moves backward. FIG. [Diagram 3] 11 is a diagram for explaining an operation for controlling the magnitude of output torque. FIG. [Figure 4] 4 is a diagram showing an example of maximum torque information stored in a storage unit 31. FIG. [Diagram 5]4 is a sequence showing an operation for controlling the magnitude of output torque. [Figure 6] 4 is a sequence showing an operation for determining a maximum torque. [Figure 7] 4 is a sequence showing an operation for determining an output torque. [Figure 8] 11A and 11B are diagrams for explaining an operation of reducing the operation torque by a predetermined rate. [Figure 9] FIG. 11 is a diagram showing an example of output torque information according to a first modified example. [Figure 10] FIG. 11 is a diagram illustrating an example of a processing sequence according to a first modified example. [Figure 11] FIG. 11 is a diagram showing an example of output torque suppression information according to a second modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] <Overview of Vehicle S> FIG. 1 is a diagram for explaining an overview of a vehicle S according to this embodiment. The vehicle S according to this embodiment is, for example, a commercial vehicle such as a truck capable of mounting a body such as a luggage compartment at the rear. The vehicle S may be a trailer head to which a trailer can be coupled. The vehicle S shown in FIG. 1 includes an accelerator sensor 10, a weight sensor 11, a G sensor 12, a driving force source control device 20, an alarm device 21, and an acceleration control device 30. The vehicle S has a function of controlling the magnitude of a torque (hereinafter referred to as "output torque") generated by a driving force source (not shown) included in the vehicle S based on a torque (hereinafter referred to as "operation torque") corresponding to the opening degree of an accelerator pedal (not shown) included in the vehicle S. The driving force source of the vehicle S is, for example, at least one of an engine and a motor.

[0024] The accelerator sensor 10 is a sensor that detects the amount of depression of the accelerator pedal when the driver depresses it. The accelerator sensor 10 detects the difference (distance) between the position before the driver depresses the accelerator pedal and the position when the driver depresses the accelerator pedal as the amount of depression. The weight sensor 11 is a sensor that detects the weight of the vehicle S. The weight sensor 11 detects the weight of the vehicle S including the weight of the body. If there is a load on the body, the weight sensor 11 detects the weight of the vehicle S including the weight of the body and the weight of the load. The G sensor 12 is a sensor that detects the acceleration of the vehicle S.

[0025] The driving force source control device 20 is a device for adjusting the output of a driving force source (engine or motor) equipped in the vehicle S based on the output torque output by the acceleration control device 30. The driving force source control device 20 adjusts the output of the driving force source, for example, by changing the intake amount and ignition timing of the engine or by changing the current flowing through the motor based on the output torque. The notification device 21 is a device for notifying the driver of the output torque output by the acceleration control device 30. The notification device 21, for example, displays an image corresponding to a symbol or character indicating the output torque on a display (not shown) equipped in the vehicle S, or outputs a sound corresponding to the output torque from a speaker (not shown) equipped in the vehicle S. The notification device 21 may transmit the image and sound corresponding to the output torque to an information terminal held by the driver via wireless communication.

[0026] The acceleration control device 30 controls the magnitude of the output torque when the vehicle S is reversing, based on the accelerator pedal opening, the weight of the vehicle S, and the gradient of the road surface on which the tires of the vehicle S contact. The acceleration control device 30 acquires, for example, the accelerator pedal opening detected by the accelerator sensor 10, the weight of the vehicle S detected by the weight sensor 11, and the acceleration of the vehicle S detected by the G sensor 12. The acceleration control device 30 then executes a process of determining the output torque of the driving force source provided in the vehicle S, based on the accelerator pedal opening, the pedaling speed calculated from the accelerator pedal opening, the weight of the vehicle S, and the gradient of the road surface calculated from the acceleration of the vehicle S. The acceleration control device 30 is a housing including electronic components or a printed circuit board on which electronic components are mounted.

[0027] At the rear of the vehicle S, to which a body such as a loading platform is mounted or connected, the shape of the body and the position where the body is mounted or connected vary depending on the type of vehicle S, so the body becomes an obstacle and it is difficult to install a camera or a sensor for measuring the distance between the vehicle S and surrounding objects. The objects around the vehicle S are, for example, people, animals, plants, walls, steps that make it difficult for the vehicle S to travel, and other vehicles different from the vehicle S. Therefore, it is difficult to provide the vehicle S with a function to suppress the vehicle S from erroneously starting backwards. However, when the weight of the vehicle S increases due to the body and cargo, or when there is a slope on the road surface, the driver tends to press the accelerator pedal hard to avoid a lack of traction. As a result, the vehicle S may erroneously start backwards.

[0028] Therefore, when the vehicle S moves backward, the acceleration control device 30 determines the maximum value of the output torque (hereinafter referred to as "maximum torque") to be generated by the driving force source based on the opening degree and depression speed of the accelerator pedal, the weight of the vehicle S, and the gradient of the road surface on which the vehicle S travels. As an example, the acceleration control device 30 determines the maximum torque to be a torque smaller than the maximum value of the output torque that the driving force source can generate when the opening degree of the accelerator pedal is equal to or greater than the opening degree threshold and the depression speed is equal to or greater than the speed threshold, the weight of the vehicle S is equal to or greater than the weight threshold, and the gradient in the direction in which the vehicle S moves backward is equal to or greater than the gradient threshold. Details of the opening degree threshold, the speed threshold, the weight threshold, and the gradient threshold will be described later. Then, the acceleration control device 30 controls the magnitude of the output torque via the driving force source control device 20 so that the driving force source generates an output torque less than the determined maximum torque. By operating in this manner, the acceleration control device 30 can suppress the acceleration of the vehicle S to a predetermined value or less, thereby preventing the vehicle S from erroneously starting suddenly backward (i.e., erroneous starting backward). The configuration and operation of the acceleration control device 30 will now be described in detail.

[0029] <Configuration of acceleration control device 30> The acceleration control device 30 includes a storage unit 31 and a control unit 32. The control unit 32 includes an acquisition unit 321, a torque control unit 322, and a notification unit 323.

[0030] The storage unit 31 includes a storage medium such as a read only memory (ROM), a random access memory (RAM), a hard disk drive (HDD), a solid state drive (SSD), etc. The storage unit 31 stores a program executed by the control unit 32 and various information for controlling the magnitude of the output torque of the driving force source provided in the vehicle S.

[0031] The control unit 32 is a processor such as a CPU (Central Processing Unit) or an ECU (Electronic Control Unit). The control unit 32 executes a program stored in the storage unit 31 to function as an acquisition unit 321, a torque control unit 322, and a notification unit 323. The control unit 32 may be configured with one processor, or may be configured with multiple processors or a combination of one or more processors and an electronic circuit. The configuration of each unit realized by the control unit 32 will be described below.

[0032] The acquisition unit 321 acquires the opening degree of an accelerator pedal equipped in the vehicle S, the depression speed when the driver depresses the accelerator pedal, the weight of the vehicle S, and the gradient of the road surface on which the vehicle S contacts. The acquisition unit 321 acquires, for example, the depression amount detected by the accelerator sensor 10, the weight of the vehicle S detected by the weight sensor 11, and the acceleration of the vehicle S detected by the G sensor 12. The acquisition unit 321 then specifies the opening degree and depression speed of the accelerator pedal based on the acquired depression amount, and specifies the gradient of the road surface on which the vehicle S contacts based on the acquired acceleration of the vehicle S, thereby acquiring the opening degree and depression speed of the accelerator pedal, and the gradient of the road surface.

[0033] For example, the acquisition unit 321 identifies the ratio (in %) of the depression amount detected by the accelerator sensor 10 to the maximum depression amount of the accelerator pedal as the accelerator pedal opening. The acquisition unit 321 identifies the ratio (in % / second) of a quotient obtained by dividing the difference between the depression amount acquired at the current time and a time unit time (e.g., 0.1 seconds) before the current time by the current time to the maximum depression amount of the accelerator pedal as the accelerator pedal depression speed. The acquisition unit 321 identifies the gradient of the road surface on which the vehicle S is in contact based on the acceleration of the vehicle S detected by the G sensor 12 and the gravitational acceleration. The gradient indicates a positive angle value when the vehicle S is reversing in an upward gradient, and indicates a negative angle value when the vehicle S is reversing in a downward gradient.

[0034] FIG. 2 is a diagram for explaining the gradient in the direction in which the vehicle S is reversing. FIG. 2(a) shows a case in which the vehicle S is reversing in an upward gradient. FIG. 2(b) shows a case in which the vehicle S is reversing in a downward gradient. FIG. 2(c) shows a case in which the vehicle S is reversing on a flat road surface. In FIG. 2(a), the vehicle S is reversing in an upward gradient, so the gradient (angle θ shown in FIG. 2(a)) identified by the acquisition unit 321 is a positive angle. In FIG. 2(b), the vehicle S is reversing in a downward gradient, so the gradient (angle θ shown in FIG. 2(b)) identified by the acquisition unit 321 is a negative angle. In FIG. 2(c), the vehicle S is reversing on a flat road surface, so the gradient (angle θ shown in FIG. 2(c)) identified by the acquisition unit 321 is 0 degrees.

[0035] Furthermore, the acquisition unit 321 may acquire operation information indicating a forward or reverse operation from an external device (not shown) in response to the driver's operation to move the vehicle S forward or backward. An "operation to move the vehicle S backward" is, for example, an operation in which the driver depresses the accelerator pedal more than a certain level with a shift lever (not shown) provided on the vehicle S set to a position indicating reverse.

[0036] When the torque control unit 322 receives an operation to move the vehicle S backward, the torque control unit 322 controls the magnitude of the output torque of the driving force source provided in the vehicle S based on the accelerator pedal opening, the accelerator pedal depression speed, the weight of the vehicle S, and the gradient of the road surface on which the vehicle S is in contact in the backward direction of the vehicle S. On the other hand, when the torque control unit 322 receives an operation to move the vehicle S forward, the torque control unit 322 controls the magnitude of the output torque so that the driving force source generates an operation torque corresponding to the accelerator pedal opening. For example, the torque control unit 322 outputs the determined output torque to the driving force source control device 20, and the driving force source control device 20 controls the driving force source to generate an output torque. By operating the torque control unit 322 in this way, when the vehicle S moves backward, the torque control unit 322 can determine an output torque different from the operation torque corresponding to the driver's operation, unlike when the vehicle S moves forward. As a result, the torque control unit 322 can reduce the output torque when the vehicle S moves backward, and can suppress the acceleration of the vehicle S to a predetermined value or less.

[0037] For example, when an operation to move the vehicle S backward is received, the torque control unit 322 determines the output torque under the condition that the opening degree of the accelerator pedal is equal to or greater than the opening degree threshold (first threshold) and the depression speed is equal to or greater than the speed threshold (second threshold). The opening degree threshold is, for example, 80%, and the speed threshold is, for example, 400%. The opening degree threshold and the speed threshold are determined by experiment or simulation. On the other hand, when the opening degree of the accelerator pedal is less than the opening degree threshold or the depression speed is less than the speed threshold, the torque control unit 322 controls the magnitude of the output torque so that the operation torque is generated in the driving force source. By operating in this manner, the torque control unit 322 can reduce the output torque when it is estimated that the driver has performed an operation that may cause a sudden start. In the following description, "the opening degree of the accelerator pedal is equal to or greater than the opening degree threshold and the depression speed is equal to or greater than the speed threshold" is referred to as "predetermined condition".

[0038] For example, when a predetermined condition is satisfied when the vehicle S is moving backwards, the torque control unit 322 controls the magnitude of the output torque so that the driving force source generates the smaller torque of either the operation torque corresponding to the accelerator pedal opening degree or the maximum torque which is the maximum value of the output torque. FIG. 3 is a diagram for explaining the operation of controlling the magnitude of the output torque. The horizontal axis of FIG. 3 indicates the accelerator pedal opening degree, and the vertical axis of FIG. 3 indicates the output torque. The output torque QM shown in FIG. 3 is the maximum value of the output torque that can be generated by the driving force source provided in the vehicle S (i.e., the initial value of the maximum torque), the torque E0 is the operation torque, and the torque E1, the torque E2, and the torque E3 are examples of the maximum value of the output torque.

[0039] For example, when torque control unit 322 determines that the maximum torque is torque E2, if the accelerator opening is less than opening A2, torque control unit 322 outputs an output torque to driving force source control device 20 so that the driving force source generates torque E0 (operation torque). On the other hand, if the accelerator opening is equal to or greater than opening A2, torque control unit 322 outputs an output torque so that the driving force source generates output torque Q2 (i.e., torque E2, which is the maximum value of the output torque). By operating in this manner, torque control unit 322 can control the magnitude of the output torque so that the driving force source does not generate torque greater than the determined maximum torque.

[0040] For example, when the vehicle S satisfies a predetermined condition when it moves backward, the weight is equal to or greater than the weight threshold (third threshold), and the gradient in the direction in which the vehicle S moves backward is equal to or greater than the gradient threshold (fourth threshold), the torque control unit 322 determines the maximum torque as the first torque. The first torque is a multiplied value obtained by multiplying the maximum value of the output torque that the driving force source equipped in the vehicle S can generate by the first ratio, and is, for example, the output torque Q1 shown in FIG. 3. The first ratio is a ratio set by an experiment or a simulation, and is, for example, a fixed value that is equal to or greater than 90% and less than 100%. The first ratio may be determined by the driver operating the instrument panel within a range of equal to or greater than 90% and less than 100%. The weight threshold is, for example, the sum of the weight of the vehicle S to which the body is connected and half the weight indicated by the maximum load capacity. The gradient threshold is, for example, 0 degrees (i.e., flat), but an angle based on the detection error of the G sensor 12 may be added or subtracted (so-called offset).

[0041] By operating torque control unit 322 in this manner, when the greatest traction force is required, torque control unit 322 can output the output torque required to reverse vehicle S while suppressing the maximum torque which is smaller than the maximum value of the output torque that the driving force source can generate. As a result, even when the traction force required to reverse vehicle S is large, it is possible to avoid a shortage of traction force while suppressing the maximum torque.

[0042] For example, when the vehicle S satisfies a predetermined condition when it moves backward, the weight is equal to or greater than a weight threshold, and the gradient in the direction in which the vehicle S moves backward is less than a gradient threshold, the torque control unit 322 determines the maximum torque as the second torque. The second torque is a multiplied value obtained by multiplying the maximum value of the output torque that the driving force source can generate by the second ratio, which is smaller than the first ratio, and is, for example, the output torque Q2 shown in FIG. 3. The second ratio is a ratio set by an experiment or simulation, and is, for example, a fixed value that is equal to or greater than 60% and less than 90%. The second ratio may be determined by the driver operating the instrument panel within a range of equal to or greater than 60% and less than 90%.

[0043] By operating the torque control unit 322 in this manner, even if the weight of the vehicle S is large, when the gradient of the road surface is small, the second torque smaller than the first torque determined when the weight of the vehicle S is large and the gradient of the road surface is large can be determined as the maximum torque. As a result, a traction force corresponding to the weight of the vehicle S can be generated while keeping the maximum torque lower than the first torque, so that it is possible to prevent the vehicle S from erroneously starting suddenly when moving backwards.

[0044] For example, when the vehicle S satisfies a predetermined condition when it moves backward, the weight is less than the weight threshold, and the gradient in the direction in which the vehicle S moves backward is equal to or greater than the gradient threshold, the torque control unit 322 determines the second torque to be the maximum torque. By operating in this manner, even if the gradient of the road surface is large, when the weight of the vehicle S is small, the torque control unit 322 can determine the second torque, which is smaller than the first torque determined when the weight of the vehicle S is large and the gradient of the road surface is large, as the maximum torque. As a result, it is possible to generate a traction force corresponding to the gradient of the road surface while suppressing the maximum torque to be smaller than the first torque, and therefore it is possible to suppress erroneous sudden acceleration when the vehicle S moves backward.

[0045] For example, when the vehicle S satisfies a predetermined condition when it moves backward, the weight is less than a weight threshold, and the gradient in the direction in which the vehicle S moves backward is less than a gradient threshold, the torque control unit 322 determines the maximum torque as the third torque. The third torque is a multiplied value obtained by multiplying the maximum value of the output torque that the driving force source can generate by the third ratio, which is smaller than the second ratio, and is, for example, the output torque Q3 shown in FIG. 3. The third ratio is a ratio set by an experiment or simulation, and is, for example, a fixed value that is equal to or greater than 10% and less than 40%. The third ratio may be determined by the driver operating the instrument panel within a range of equal to or greater than 10% and less than 40%.

[0046] By operating the torque control unit 322 in this manner, it is possible to reduce the maximum torque when the weight of the vehicle S is light and the gradient of the road surface is small (i.e., when the smallest tractive force is acceptable). Furthermore, the torque control unit 322 can determine the third torque, which is smaller than the first torque and the second torque, as the maximum torque when the smallest tractive force is acceptable. As a result, it is possible to generate a tractive force corresponding to the gradient of the road surface while suppressing the maximum torque below the first torque and the second torque, and therefore it is possible to prevent the vehicle S from erroneously starting suddenly when moving backwards.

[0047] Furthermore, when the vehicle S moves backward, the torque control unit 322 may determine the maximum torque according to the accelerator pedal opening degree, the pedal depression speed, the weight of the vehicle S, and the gradient in the direction in which the vehicle S moves backward, by referring to the maximum torque information stored in the storage unit 31. FIG. 4 is a diagram showing an example of the maximum torque information stored in the storage unit 31. As shown in FIG. 4, the storage unit 31 stores maximum torque information indicating the maximum torque corresponding to the accelerator pedal opening degree condition, the pedal depression speed condition, the weight condition of the vehicle S, and the gradient condition of the road surface. The ratios shown in FIG. 4 are ratios to the maximum torque that can be generated by the driving force source provided in the vehicle S, where "90%" is the first ratio, "60%" is the second ratio, and "35%" is the third ratio.

[0048] As an example, the torque control unit 322 determines that the opening degree of the accelerator pedal is equal to or greater than the opening degree threshold, the depression speed is equal to or greater than the speed threshold, the weight of the vehicle S is less than the weight threshold, and the gradient of the road surface is less than the gradient threshold. Then, by referring to the maximum torque information stored in the storage unit 31, the torque control unit 322 determines that the maximum torque corresponding to the determined conditions is the "third torque" and determines the maximum torque to be the third torque. By operating in this manner, the torque control unit 322 can reduce the processing load compared to determining the maximum torque without referring to the storage unit 31.

[0049] Furthermore, when a predetermined time has elapsed since the time when the maximum torque was determined to be the second torque or the third torque, the torque control unit 322 may increase the maximum torque each time a unit time (e.g., 0.1 second) elapses, with the maximum value of the torque that the driving force source can generate as an upper limit. The predetermined time is a time during which the driver can determine whether or not an erroneous start has occurred, and is, for example, 3 seconds. By operating in this manner, the torque control unit 322 can determine the torque according to the driver's operation after the driver has determined that an erroneous start has not occurred.

[0050] When the torque control unit 322 determines that the maximum torque is smaller than the maximum torque that the driving force source can generate, the notification unit 323 notifies the driver via the notification device 21. That is, when a predetermined condition is satisfied when the vehicle S is moving backwards, the notification unit 323 notifies the driver via the notification device 21 that the maximum torque has been changed. For example, the notification unit 323 displays an image corresponding to a symbol or character indicating the output torque on a display provided in the vehicle S or an information terminal provided by the driver via the notification device 21. The notification unit 323 may also output a sound corresponding to the output torque from a speaker provided in the vehicle S or an information terminal provided by the driver via the notification device 21.

[0051] <Processing sequence in the acceleration control device 30> Figures 5, 6 and 7 are diagrams showing examples of processing sequences in the acceleration control device 30. The processing sequence shown in Figure 5 is a sequence showing an operation for controlling the magnitude of the output torque, the processing sequence shown in Figure 6 is a sequence showing an operation for determining the maximum torque, and the processing sequence shown in Figure 7 is a sequence showing an operation for determining the output torque. The processing sequence shown in Figure 6 corresponds to S13 in Figure 5, and the processing sequence shown in Figure 7 corresponds to S14 in Figure 5. The acceleration control device 30 repeats the processing sequences shown in Figures 5, 6 and 7 at regular time intervals (for example, every time a unit time has elapsed).

[0052] First, the operation of controlling the magnitude of the output torque will be described with reference to Fig. 5. The acquisition unit 321 acquires the accelerator pedal opening degree A, weight C, and acceleration (S10). The acquisition unit 321 acquires the accelerator pedal depression speed B based on the accelerator pedal opening degree A and the gradient D of the road surface on which the vehicle S is in contact based on the acquired acceleration, thereby acquiring the depression speed B and gradient D (S11).

[0053] If accelerator pedal opening A is equal to or greater than the opening threshold and depression speed B is equal to or greater than the speed threshold (YES in S12), torque control unit 322 executes a process for determining maximum torque (maximum torque determination process shown in FIG. 5) (S13). Then, torque control unit 322 executes a process for determining output torque and outputting it to driving force source control device 20 (output torque control process shown in FIG. 5) (S14). If accelerator pedal opening A is less than the threshold or depression speed B is less than the speed threshold (NO in S12), torque control unit 322 executes output torque control process without executing maximum torque determination process (S14).

[0054] Next, the operation of the maximum torque determination process shown in S13 of Fig. 5 will be described with reference to Fig. 6. If the weight C is equal to or greater than the weight threshold and the gradient D is equal to or greater than the gradient threshold (YES in S20), the torque control unit 322 determines the maximum torque to be a first torque obtained by multiplying the maximum torque that the driving force source can generate by the first rate (S21). If the weight C is less than the weight threshold or the gradient D is less than the gradient threshold (NO in S20), the torque control unit 322 determines whether the weight C is equal to or greater than the weight threshold or the gradient D is equal to or greater than the gradient threshold (S22).

[0055] If the weight C is equal to or greater than the weight threshold or the gradient D is equal to or greater than the gradient threshold (YES in S22), that is, if "weight C is equal to or greater than the weight threshold and the gradient D is less than the gradient threshold" or "weight C is less than the weight threshold and the gradient D is equal to or greater than the gradient threshold", the torque control unit 322 determines the second torque to be the maximum torque (S23). The second torque is a multiplication value obtained by multiplying the maximum torque that the driving force source can generate by a second rate that is smaller than the first rate. If the weight C is equal to or greater than the weight threshold or the gradient D is not equal to or greater than the gradient threshold (NO in S22), that is, if "weight C is less than the weight threshold and the gradient D is less than the gradient threshold", the torque control unit 322 determines the third torque to be the maximum torque (S24). The third torque is a multiplication value obtained by multiplying the maximum torque that the driving force source can generate by a third rate that is smaller than the second rate.

[0056] Furthermore, the operation of the output torque control process shown in S14 of Fig. 5 will be described with reference to Fig. 7. Torque control unit 322 identifies the operation torque corresponding to accelerator pedal opening degree A (S30). If accelerator pedal opening degree A is equal to or greater than the opening degree threshold and depression speed B is not equal to or greater than the speed threshold (NO in S31), i.e., if "predetermined conditions are not satisfied", torque control unit 322 controls the magnitude of the output torque generated by the drive force source using the identified steering torque as the output torque (S32).

[0057] When the accelerator pedal opening degree A is equal to or greater than the opening degree threshold and the depression speed B is equal to or greater than the speed threshold (YES in S31), i.e., when the "predetermined condition is satisfied", the torque control unit 322 determines whether the operation torque is equal to or greater than the maximum torque (S33). When the operation torque is equal to or greater than the maximum torque (YES in S33), the torque control unit 322 sets the maximum torque as the output torque and controls the magnitude of the output torque generated by the driving force source (S34). On the other hand, when the operation torque is less than the maximum torque (NO in S33), the torque control unit 322 sets the operation torque as the output torque and controls the magnitude of the output torque generated by the driving force source (S32).

[0058] <First Modification> In the above description, the torque control unit 322 controls the magnitude of the output torque generated by the driving force source by determining the maximum value of the output torque generated by the driving force source, but the present invention is not limited to this. The torque control unit 322 may control the magnitude of the output torque generated by the driving force source by determining an output torque that is a predetermined percentage smaller than the operation torque corresponding to the accelerator pedal opening.

[0059] Fig. 8 is a diagram for explaining the operation of reducing the operation torque by a predetermined percentage. The horizontal axis of Fig. 8 indicates the accelerator pedal opening, and the vertical axis of Fig. 8 indicates the output torque. The output torque QM shown in Fig. 8 is the maximum value of the output torque that can be generated by the driving force source equipped in the vehicle S (i.e., the initial value of the maximum torque). The torque E0 shown in Fig. 8 is the operation torque. The torque F1, torque F2, and torque F3 shown in Fig. 8 are output torques obtained by reducing the operation torque by a predetermined percentage.

[0060] For example, when the vehicle S satisfies a predetermined condition when it reverses, the weight is equal to or greater than a weight threshold (third threshold), and the gradient in the direction in which the vehicle S reverses is equal to or greater than a gradient threshold (fourth threshold), the torque control unit 322 determines the first torque as the output torque. The first torque is a torque obtained by reducing the operation torque by a first ratio, and is the torque F1 shown in FIG. 8. The first ratio is a ratio determined by an experiment or a simulation, and is, for example, a fixed value greater than 0% and equal to or less than 10%. The first ratio may be determined by the driver operating the instrument panel within a range greater than 0% and equal to or less than 10%. By operating the torque control unit 322 in this manner, the torque control unit 322 can determine the operation torque as the output torque when the weight of the vehicle S is large and the angle of the upward gradient is large. As a result, the vehicle S can avoid a lack of traction force.

[0061] For example, when the vehicle S satisfies a predetermined condition when it reverses, the weight is equal to or greater than the weight threshold, and the gradient in the direction in which the vehicle S reverses is less than the gradient threshold, the torque control unit 322 determines the second torque as the output torque. The second torque is a torque obtained by reducing the operation torque corresponding to the opening degree of the accelerator pedal by a second ratio greater than the first ratio, and is torque F2 shown in FIG. 8. As an example, the second ratio is a fixed value greater than 10% and equal to or less than 40%, and is determined by an experiment or simulation. The first ratio may be determined by the driver operating the instrument panel within a range greater than 10% and equal to or less than 40%. By operating the torque control unit 322 in this manner, the torque control unit 322 can suppress the vehicle S from erroneously starting suddenly when it reverses due to the road surface in the reverse direction having a downward gradient, even when the weight of the vehicle S is large.

[0062] For example, when the vehicle S satisfies a predetermined condition when reversing, the weight is less than the weight threshold, and the gradient in the direction in which the vehicle S reverses is equal to or greater than the gradient threshold, the torque control unit 322 determines the second torque as the output torque. In this case, the second torque may be the same as or different from the second torque determined when the weight is equal to or greater than the weight threshold and the gradient in the direction in which the vehicle S reverses is less than the gradient threshold. By operating in this manner, the torque control unit 322 can suppress the vehicle S from erroneously starting suddenly when reversing due to the weight of the vehicle S being small, even if the road surface in the reverse direction is an uphill slope.

[0063] For example, when the vehicle S satisfies a predetermined condition when it reverses, the weight is less than the weight threshold, and the gradient in the direction in which the vehicle S reverses is less than the gradient threshold, the torque control unit 322 determines the third torque as the output torque. The third torque is a torque obtained by reducing the operation torque corresponding to the opening degree of the accelerator pedal by a third ratio greater than the second ratio, and is torque F3 shown in FIG. 8. The third ratio is a fixed value greater than 60% and less than or equal to 90%, and is determined by an experiment or a simulation. The third ratio may be determined by the driver operating the instrument panel within a range greater than 60% and less than or equal to 90%. By operating the torque control unit 322 in this manner, the torque control unit 322 can reduce the output torque to the smallest when the weight of the vehicle S is small and the road surface in the direction in which the vehicle S reverses is downwardly sloping (i.e., when the vehicle S is most likely to erroneously start suddenly).

[0064] Furthermore, when the vehicle S moves backward, the torque control unit 322 may determine the output torque based on the accelerator pedal opening degree, the depression speed, the weight of the vehicle S, and the gradient in the direction in which the vehicle S moves backward, by referring to the output torque information stored in the storage unit 31. FIG. 9 is a diagram showing an example of the output torque information according to the first modified example. As shown in FIG. 9, the storage unit 31 stores output torque information indicating the output torque corresponding to the accelerator pedal opening degree condition, the depression speed condition, the weight condition of the vehicle S, and the gradient condition of the road surface. As an example, the output torque information includes the type of the magnitude of the output torque (first torque, second torque, third torque) and the ratio of the output torque to the operation torque (for example, in FIG. 9, the second torque is 70% of the operation torque), as shown in "output torque" in FIG. 9.

[0065] As an example, the torque control unit 322 determines that the opening degree of the accelerator pedal is equal to or greater than the opening degree threshold, the depression speed is equal to or greater than the speed threshold, the weight of the vehicle S is less than the weight threshold, and the gradient of the road surface is less than the gradient threshold. Then, by referring to the output torque information stored in the storage unit 31, the torque control unit 322 determines that the output torque corresponding to the determined conditions is the "third torque" and determines the output torque to be the third torque. By operating in this manner, the torque control unit 322 can reduce the processing load compared to determining the output torque without referring to the storage unit 31.

[0066] Fig. 10 is a diagram showing an example of a processing sequence according to the first modified example. The processing sequence shown in Fig. 10 shows an operation in which the acceleration control device 30 determines an output torque. The acceleration control device 30 executes the processing sequence shown in Fig. 10 when an operation to move the vehicle S backward is received.

[0067] The acquisition unit 321 acquires the accelerator pedal opening degree A from the accelerator sensor 10, the weight C of the vehicle S from the weight sensor 11, and the acceleration of the vehicle S from the G sensor 12 (S40). The acquisition unit 321 determines the depression speed B based on the difference between the opening degree A at the current time and the opening degree A a unit time before the current time, and determines the gradient D based on the acceleration of the vehicle S and the gravitational acceleration (S41). If the opening degree A is less than the opening degree threshold or the depression speed B is less than the speed threshold (NO in S42), the torque control unit 322 determines the output torque to be the operation torque (i.e., the first torque) (S44).

[0068] When the opening degree A is equal to or greater than the opening degree threshold and the depression speed B is equal to or greater than the speed threshold (YES in S42), the torque control unit 322 determines whether the weight C is equal to or greater than the weight threshold and the gradient D is equal to or greater than the gradient threshold (S43). When the weight C is equal to or greater than the weight threshold and the gradient D is equal to or greater than the gradient threshold (YES in S43), the torque control unit 322 determines whether the output torque is the operation torque (S44). When the weight C is less than the weight threshold or the gradient D is less than the gradient threshold (NO in S43), the torque control unit 322 determines whether the weight C is equal to or greater than the weight threshold or the gradient D is equal to or greater than the gradient threshold (S45). When the weight C is equal to or greater than the weight threshold or the gradient D is equal to or greater than the gradient threshold (YES in S45), the torque control unit 322 determines the output torque to be the second torque (S46). When the weight C is less than the weight threshold and the gradient D is less than the gradient threshold (NO in S45), the torque control unit 322 determines the output torque to be the third torque (S47).

[0069] <Second Modification> In the above description, the torque control unit 322 has been exemplified as determining a maximum torque that is the maximum value of the output torque, or determining an output torque that is a predetermined percentage smaller than the operation torque, but the present invention is not limited to this. The torque control unit 322 may determine whether or not to control the output torque when a predetermined condition is satisfied when the vehicle S reverses. If the torque control unit 322 does not control the output torque, the driving force source control device 20 adjusts the output of the driving force source using the operation torque. Note that, if the torque control unit 322 determines not to control the output torque, it may output information indicating that it has been determined not to control the output torque to the driving force source control device 20.

[0070] For example, when the weight of the vehicle S is equal to or greater than the weight threshold when the vehicle S is reversing, even if the opening degree of the accelerator pedal is equal to or greater than the opening degree threshold and the depression speed is equal to or greater than the speed threshold, the torque control unit 322 does not control the magnitude of the output torque. That is, when the weight of the vehicle S is equal to or greater than the weight threshold when the vehicle S is reversing, the torque control unit 322 does not suppress the output torque. For example, when the weight is less than the weight threshold and the gradient in the direction in which the vehicle S is reversing is equal to or greater than the gradient threshold, the torque control unit 322 does not control the magnitude of the output torque even if the opening degree of the accelerator pedal is equal to or greater than the opening degree threshold and the depression speed is equal to or greater than the speed threshold.

[0071] For example, when the vehicle S satisfies a predetermined condition when it reverses, the weight is less than the weight threshold, and the gradient in the direction in which the vehicle S reverses is less than the gradient threshold, the torque control unit 322 determines the fourth torque as the output torque and controls the magnitude of the output torque of the driving force source. The fourth torque is a torque obtained by reducing the operation torque corresponding to the opening degree of the accelerator pedal by a fourth ratio. As an example, the fourth ratio is a fixed value that is greater than 10% and less than 40%, and is determined by an experiment or a simulation. The fourth ratio may be the same ratio as the first ratio, the second ratio, or the third ratio, or may be a different ratio. By the torque control unit 322 operating as described above, it is possible to suppress the output torque in a case where it is most likely to erroneously start suddenly. As a result, it is possible to avoid a traction force shortage caused by erroneously suppressing the output torque.

[0072] Furthermore, when the vehicle S moves backward, the torque control unit 322 may determine whether or not to determine the output torque by referring to the output torque suppression information stored in the storage unit 31. Fig. 11 is a diagram showing an example of the output torque suppression information according to the second modified example. As shown in Fig. 11, the storage unit 31 stores information indicating whether or not to suppress the output torque corresponding to conditions of the accelerator pedal opening degree, the depression speed, the weight of the vehicle S, and the gradient of the road surface.

[0073] As an example, the torque control unit 322 determines that the opening degree of the accelerator pedal is equal to or greater than the opening degree threshold, the depression speed is equal to or greater than the speed threshold, the weight of the vehicle S is less than the weight threshold, and the gradient of the road surface is less than the gradient threshold. Then, the torque control unit 322 determines to determine the output torque by referring to the output torque suppression information stored in the storage unit 31, and determines the output torque to be the fourth torque. Then, the torque control unit 322 controls the driving force source via the driving force source control device 20 so that the driving force source outputs the fourth torque. By operating in this manner, the torque control unit 322 can reduce the processing load compared to determining whether or not to determine the output torque without referring to the storage unit 31.

[0074] <Third Modification> In the above description, an example of the operation of determining the first torque using the first ratio indicating a ratio less than 100% has been given, but the present invention is not limited to this. The first ratio may be a ratio indicating 100%. By the torque control unit 322 determining the first torque using the first ratio indicating 100%, it is possible to avoid a traction force shortage when there is a high probability of a traction force shortage occurring due to the weight of the vehicle S and the gradient of the road surface.

[0075] <Fourth Modification> In the above description, the torque control unit 322 has been described as executing the maximum torque determination process and the output torque control process shown in Fig. 5, but the present invention is not limited to this. In the vehicle S, for example, the torque control unit 322 may execute the maximum torque determination process, and the driving force source control device 20 may execute the output torque control process. In this case, the torque control unit 322 may generate information indicating whether or not the maximum torque determination process has been executed based on whether or not the opening degree of the accelerator pedal is equal to or greater than an opening degree threshold and the depression speed is equal to or greater than a speed threshold, and output the information to the driving force source control device 20 in association with the maximum torque or the operation torque.

[0076] <Effects of the acceleration control device 30> As described above, the acceleration control device 30 has an acquisition unit 321 that acquires the opening degree of the accelerator pedal equipped on the vehicle S to which the body can be connected, the accelerator pedal depression speed when the driver depresses the accelerator pedal, the weight of the vehicle S, and the gradient of the road surface on which the vehicle S contacts, and a torque control unit 322 that controls the magnitude of the output torque of the driving force source equipped on the vehicle S based on the accelerator pedal opening degree, depression speed, weight, and the gradient of the road surface in the direction in which the vehicle S reverses when an operation to reverse the vehicle S is received.

[0077] By configuring the acceleration control device 30 in this manner, when an operation to move the vehicle S backward is received and it is determined that the vehicle S is in a state where it is likely to start suddenly, the acceleration control device 30 can determine a maximum torque smaller than the operation torque corresponding to the accelerator pedal opening. As a result, by suppressing the acceleration of the vehicle S to a predetermined value or less, the acceleration control device 30 can prevent the vehicle S from erroneously starting in the backward direction, thereby improving the safety of the vehicle S on which the body can be mounted.

[0078] Although the present invention has been described above using the embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments, and various modifications and changes are possible within the scope of the gist of the present invention. For example, all or part of the device can be configured by distributing or integrating functionally or physically in any unit. In addition, new embodiments resulting from any combination of multiple embodiments are also included in the embodiments of the present invention. The effect of the new embodiment resulting from the combination combines the effect of the original embodiment. [Explanation of symbols]

[0079] 10 Accelerator Sensor 11 Weight Sensor 12 G Sensor 20 Driving force source control device 21 Notification device 30 Acceleration control device 31 Storage section 32 Control section 321 Acquisition Department 322 Torque control section 323 Information Department

Claims

1. An acquisition unit that acquires an opening degree of an accelerator pedal equipped in a vehicle to which a body can be connected, a depression speed when a driver depresses the accelerator pedal, a weight of the vehicle, and a gradient of a road surface on which the vehicle contacts; a torque control unit that controls a magnitude of an output torque of a driving force source provided in the vehicle, when an operation to move the vehicle backward is received, based on an opening degree of the accelerator pedal, the depression speed, the weight, and a gradient of the road surface in a direction in which the vehicle moves backward; An acceleration control device having an

2. The torque control unit controls the magnitude of the output torque under conditions that the opening degree of the accelerator pedal is equal to or greater than a first threshold value and the depression speed is equal to or greater than a second threshold value. The acceleration control device according to claim 1 .

3. the torque control unit controls the magnitude of the output torque so that the driving force source generates a torque having a smaller magnitude between an operation torque corresponding to an opening degree of the accelerator pedal and a maximum torque which is a maximum value of the output torque. The acceleration control device according to claim 2 .

4. the torque control unit determines, when the weight is equal to or greater than a third threshold and the gradient in the direction in which the vehicle is reversing is equal to or greater than a fourth threshold, the maximum torque to be a first torque that is a multiplied value obtained by multiplying a maximum value of the output torque that the driving force source can generate by a first rate; 4. The acceleration control device according to claim 3.

5. when the weight is equal to or greater than the third threshold and the gradient in the direction in which the vehicle reverses is less than the fourth threshold, the torque control unit determines the maximum torque to be a second torque that is a multiplied value obtained by multiplying a maximum value of the output torque that can be generated by the driving force source by a second rate that is smaller than the first rate.

5. The acceleration control device according to claim 4.

6. when the weight is less than the third threshold and the gradient in the direction in which the vehicle reverses is equal to or greater than the fourth threshold, the torque control unit determines the maximum torque to be a second torque that is a multiplied value obtained by multiplying a maximum value of the output torque that can be generated by the driving force source by a second rate that is smaller than the first rate.

5. The acceleration control device according to claim 4.

7. when the weight is less than the third threshold value and the gradient in the direction in which the vehicle reverses is less than the fourth threshold value, the torque control unit determines the maximum torque to be a third torque that is a multiplied value obtained by multiplying a maximum value of the output torque that can be generated by the driving force source by a third ratio that is smaller than the second ratio.

7. The acceleration control device according to claim 5 or 6.

8. the torque control unit, when the weight is equal to or greater than a third threshold and the gradient in the direction in which the vehicle is moving backward is equal to or greater than a fourth threshold, determines, as the output torque, a first torque obtained by reducing an operation torque corresponding to an opening degree of the accelerator pedal by a first ratio. The acceleration control device according to claim 2 .

9. the torque control unit, when the weight is equal to or greater than the third threshold value and the gradient in the direction in which the vehicle is reversing is less than the fourth threshold value, determines, as the output torque, a second torque obtained by reducing the operation torque by a second rate that is greater than the first rate. The acceleration control device according to claim 8.

10. the torque control unit, when the weight is less than the third threshold value and the gradient in the direction in which the vehicle is reversing is equal to or greater than the fourth threshold value, determines, as the output torque, a second torque obtained by reducing the operation torque by a second rate that is greater than the first rate. The acceleration control device according to claim 8.

11. the torque control unit, when the weight is less than the third threshold value and the gradient in the direction in which the vehicle is reversing is less than the fourth threshold value, determines a third torque, which is obtained by reducing the operation torque by a third rate that is greater than the second rate, as the output torque.

11. The acceleration control device according to claim 9 or 10.

12. When the weight is equal to or greater than a third threshold, the torque control unit does not control the magnitude of the output torque even when the opening degree of the accelerator pedal is equal to or greater than the first threshold and the depression speed is equal to or greater than the second threshold. The acceleration control device according to claim 2 .

13. the torque control unit does not control the magnitude of the output torque when the weight is less than the third threshold and the gradient in the direction in which the vehicle is moving backward is equal to or greater than a fourth threshold, even if the opening degree of the accelerator pedal is equal to or greater than the first threshold and the depression speed is equal to or greater than the second threshold. The acceleration control device according to claim 12.

14. the torque control unit, when the weight is less than the third threshold value and the gradient in the direction in which the vehicle is reversing is less than a fourth threshold value, determines, as the output torque, a fourth torque obtained by reducing the operation torque corresponding to the opening degree of the accelerator pedal by a fourth percentage.

14. The acceleration control device according to claim 12 or 13.

15. The processor executes an acquisition step of acquiring an opening degree of an accelerator pedal provided on a vehicle to which the body can be connected, a depression speed of the accelerator pedal when a driver depresses the accelerator pedal, a weight of the vehicle, and a gradient of a road surface on which the vehicle contacts; a control process for controlling a magnitude of an output torque of a driving force source provided in the vehicle, based on an opening degree of the accelerator pedal, the depression speed, the weight, and a gradient of the road surface in a direction in which the vehicle is moving backward, when an operation to move the vehicle backward is received; The acceleration control method includes the steps of:

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