JP7480677B2 - Vehicle control device - Google Patents

Description

This disclosure relates to a vehicle control device that has a function of suppressing acceleration of a vehicle when the accelerator pedal is depressed while an obstacle is present ahead of the vehicle in the traveling direction.

One type of vehicle control device known in the art is one that is configured to release the acceleration suppression state and allow the vehicle to accelerate if the accelerator pedal is depressed continuously for a predetermined period of time or more while the vehicle's acceleration is suppressed.

When the acceleration suppression state is released in this way, the accelerator pedal is depressed heavily, increasing the possibility of the vehicle accelerating suddenly. Therefore, as described in Patent Document 1, it has been proposed that when the acceleration suppression state is released, the accelerator opening used to control the driving force be controlled to be smaller than the accelerator opening corresponding to the amount of depression of the accelerator pedal.

JP 2020-56374 A

In the device disclosed in Patent Document 1, when the acceleration suppression state is released, the accelerator opening is alternately switched at a fixed time rate between a first accelerator opening corresponding to the amount of depression of the accelerator pedal and a second accelerator opening smaller than the first accelerator opening.

As a result, although it is possible to prevent the vehicle from accelerating suddenly when the acceleration suppression state is released, the time ratio between the first accelerator opening and the second accelerator opening is constant, which has led to an issue that the vehicle acceleration differs depending on the type of vehicle, such as engine performance.

One aspect of the present disclosure is that, in a vehicle control device, when releasing the acceleration suppression state of the vehicle, it is desirable to be able to not only suppress sudden acceleration of the vehicle, but also suppress variation in the acceleration of the vehicle depending on the type of vehicle, etc.

A vehicle control device according to one aspect of the present disclosure includes an output unit (15, 45), a first accelerator opening acquisition unit (15, 41), an obstacle detection unit (55), a vehicle speed detection unit (57), an accelerator opening setting unit (61), and a time ratio control unit (63).

Here, the output unit is configured to output an output signal representing the accelerator opening to a driving force control section that controls the driving force of the vehicle in accordance with the accelerator opening.
The first accelerator opening acquisition unit is configured to acquire a first accelerator opening, which indicates the amount of depression of the accelerator pedal, from the accelerator pedal sensor.

The obstacle detection unit is configured to detect an obstacle present in the traveling direction of the vehicle, and the vehicle speed detection unit is configured to detect the vehicle speed of the vehicle.
The accelerator opening setting unit is configured to set the accelerator opening represented by an output signal output from the output unit to a driving force control section of the vehicle.

In other words, when the accelerator opening represented by the output signal is a first accelerator opening, the accelerator opening setting unit detects an obstacle by the obstacle detection unit, and the first accelerator opening is equal to or greater than a first reference opening set in advance, and the vehicle speed detected by the vehicle speed detection unit is equal to or less than a reference vehicle speed set in advance, the accelerator opening setting unit switches the accelerator opening represented by the output signal to a second accelerator opening that is smaller than the first accelerator opening.

As a result, the driving force controlled by the driving force control unit is reduced from the driving force corresponding to the first accelerator opening obtained from the accelerator pedal sensor to the driving force corresponding to the second accelerator opening, and the vehicle enters an acceleration suppression state.

In addition, when the accelerator opening represented by the output signal is the second accelerator opening, that is, when the vehicle is in an acceleration suppression state and the first accelerator opening is equal to or greater than a second reference opening set in advance for a predetermined period of time or more, the accelerator opening setting unit performs switching control to alternately switch the accelerator opening represented by the output signal between the first accelerator opening and the second accelerator opening at a predetermined cycle.

As a result, the driving force controlled by the driving force control unit becomes a driving force corresponding to a third accelerator opening between the first and second accelerator openings, and the vehicle accelerates at an appropriate rate without being suddenly accelerated by the driving force corresponding to the first accelerator opening.

In addition, when a preset time has elapsed since the start of the switching control, the accelerator opening setting unit switches the accelerator opening represented by the output signal to the first accelerator opening. As a result, the driving force controlled by the driving force control unit becomes a driving force corresponding to the first accelerator opening, and the vehicle enters a normal state in which it accelerates or decelerates according to the amount of depression of the accelerator pedal.

On the other hand, the time ratio control unit is configured to change the time ratio between the first accelerator opening and the second accelerator opening, which are alternately switched when the accelerator opening setting unit is performing switching control, in accordance with the vehicle acceleration so that the acceleration becomes a predetermined acceleration.

In other words, in the vehicle control device disclosed herein, in the switching control for transitioning the vehicle from the acceleration suppression state to the normal state, the driving force of the vehicle is controlled so that the vehicle acceleration becomes a predetermined acceleration, thereby accelerating the vehicle at a nearly constant acceleration regardless of the type of vehicle.

As a result, the sensation of acceleration felt by the occupants when the vehicle transitions from the acceleration suppression state to the normal state can be kept substantially constant regardless of the type of vehicle, thereby preventing the occupants from feeling uneasy due to fluctuations in the sensation of acceleration.

In other words, if the time ratio between the first accelerator opening and the second accelerator opening is constant in switching control, then in a small-displacement vehicle, for example, the time that the second accelerator opening is held is too long, making it impossible to accelerate. Also, in a large-displacement vehicle, for example, the time that the second accelerator opening is held is too short, causing pulsation.

In contrast, in the vehicle control device disclosed herein, the time ratio control unit controls the time ratio between the first accelerator opening and the second accelerator opening during switching control, thereby preventing such problems from occurring and providing the occupant with a stable feeling of acceleration.

1 is a block diagram showing a configuration of a vehicle control device according to an embodiment; FIG. 2 is a block diagram showing a functional configuration of a control unit. 4 is a flowchart showing an accelerator opening setting process. 4 is an explanatory diagram showing a change in accelerator opening degree represented by an output signal. FIG. 13 is a flowchart showing a time ratio control process. FIG. 11 is an explanatory diagram illustrating an on-time update operation of a relay switch.

Exemplary embodiments of the present disclosure are described with reference to the drawings.
[composition]
As shown in FIG. 1 , the vehicle includes a vehicle control device 1 , an accelerator pedal sensor 3 , a forward monitoring sensor 5 , a vehicle speed sensor 7 , a shift sensor 9 , and a driving force control unit 11 .

The vehicle control device 1 includes a second signal generating unit 13 , a relay switch 15 , a power supply coil 17 , and a control unit 50 .
The control unit 50 includes a microcomputer having a CPU 51 and a semiconductor memory such as a RAM or a ROM (hereinafter, referred to as a memory 53). Each function of the control unit 50 is realized by the CPU 51 executing a program stored in a non-transitive substantial recording medium. In this example, the memory 53 corresponds to the non-transitive substantial recording medium storing the program. Furthermore, the program is executed to execute a method corresponding to the program. The control unit 50 may include one microcomputer or multiple microcomputers.

As shown in FIG. 2, the control unit 50 has the functions of an obstacle detection unit 55, a vehicle speed detection unit 57, a shift detection unit 59, an accelerator opening setting unit 61, and a time ratio control unit 63. The method of realizing each function included in the control unit 50 is not limited to software, and some or all of the functions may be realized using one or more pieces of hardware. For example, when the above functions are realized by electronic circuits that are hardware, the electronic circuits may be realized by digital circuits, analog circuits, or a combination of these.

As shown in FIG. 1, the relay switch 15 includes a first contact 31, a second contact 33, an output side contact 35, a movable piece 37, and a coil 39. The first contact 31 is connected to a signal line 41. The signal line 41 transmits a first signal from the accelerator pedal sensor 3 to the first contact 31.

The first signal is a signal that indicates the accelerator opening detected by the accelerator pedal sensor 3 (hereinafter referred to as the first accelerator opening). The accelerator opening is expressed in percentages. When the driver is not depressing the accelerator pedal at all, the accelerator opening is 0%. When the driver depresses the accelerator pedal to its maximum, the accelerator opening is 100%.

The second contact 33 is connected to a signal line 43. The signal line 43 transmits a second signal from the second signal generating unit 13 to the second contact 33. The second signal is a signal generated by the second signal generating unit 13. The second signal is a signal that represents the second accelerator opening. The second accelerator opening is always 0%.

The output contact 35 is connected to a signal line 45. The signal line 45 is connected to the driving force control unit 11. The signal line 45 transmits an output signal from the output contact 35 to the driving force control unit 11. The output signal is a signal that represents the accelerator opening.

One end of the movable piece 37 is always connected to the output side contact 35. The other end of the movable piece 37 is connected to one of the first contact 31 and the second contact 33. That is, the movable piece 37 can move to a position where the first contact 31 and the output side contact 35 are connected (hereinafter referred to as the first position), and can also move to a position where the second contact 33 and the output side contact 35 are connected (hereinafter referred to as the second position).

The coil 39 generates a magnetic force when a current flows through it. The magnetic force generated by the coil 39 moves the movable piece 37 from the first position to the second position. Therefore, by passing a current through the coil 39 and turning on the relay switch 15, the position of the movable piece 37 can be set to the second position. Also, by cutting off the current through the coil 39 and turning off the relay switch 15, the position of the movable piece 37 can be set to the first position.

The second signal generating unit 13 generates a second signal. The second signal reaches the second contact 33 via the signal line 43. The power coil 17 passes a current through the coil 39 in response to an instruction from the accelerator opening setting unit 61 in the control unit 50, and switches the relay switch 15 from the OFF state to the ON state.

When the relay switch 15 is turned on, the output signal becomes a second signal that indicates an accelerator opening of 0%, and when the relay switch 15 is turned off, the output signal becomes a first signal that indicates a first accelerator opening that corresponds to the amount of depression of the accelerator pedal.

The accelerator pedal sensor 3 detects the first accelerator opening. The forward monitoring sensor 5 detects obstacles in front of the vehicle. The vehicle speed sensor 7 detects the vehicle speed. The shift sensor 9 detects the position of the vehicle's shift lever (hereinafter, "shift position").

The driving force control unit 11 controls the driving force of the vehicle according to the accelerator opening represented by the output signal. For example, the driving force control unit 11 sets the throttle opening according to the accelerator opening represented by the output signal. An example of the driving force control unit 11 is a power management controller.

The signal line 41 and the relay switch 15 correspond to a first accelerator opening obtaining unit in the present disclosure, and the relay switch 15 and the signal line 45 correspond to an output unit in the present disclosure.
[Accelerator opening setting process]
Next, an accelerator opening setting process that is repeatedly executed at predetermined time intervals in the control unit 50 to realize the function of the accelerator opening setting unit 61 will be described.

As shown in FIG. 3, the accelerator opening setting process first determines in S110 (S stands for step) whether the vehicle is currently in a normal state. The normal state is a state in which the movable piece 37 is in the first position and the first contact 31 and the output side contact 35 are connected.

In a normal state, the accelerator opening indicated by the output signal output from the relay switch 15 to the driving force control unit 11 is a first accelerator opening corresponding to the amount of depression of the accelerator pedal. Therefore, in a normal state, the driving force control unit 11 controls the driving force of the vehicle according to the first accelerator opening. In a normal state, if the first accelerator opening becomes large, the vehicle can start and accelerate.

If it is determined in S110 that the state is normal, the process proceeds to S120, and if it is determined that the state is not normal, the process proceeds to S140.
In S120, it is determined whether the following first to third conditions are met.

First condition: The obstacle detection unit 55 detects, via the forward monitoring sensor 50, an obstacle that exists in the traveling direction of the vehicle.
Second condition: the first accelerator opening detected by the accelerator pedal sensor 3 is equal to or greater than a first reference opening (for example, 55%) set in advance.

Third condition: the vehicle speed detected by the vehicle speed detection unit 57 using the vehicle speed sensor 7 is equal to or lower than a preset reference vehicle speed (for example, 10 km/h).
When all of the first to third conditions are met, the driver does not intend to make a sudden start, but accidentally depresses the accelerator pedal suddenly.

Therefore, in S120, if all of the first to third conditions are met, it is determined that the acceleration suppression condition is met and the process proceeds to S130, but if any of the first to third conditions are not met, the accelerator opening setting process is terminated.

In S130, the vehicle state is transitioned from the normal state to the acceleration suppression state, and the accelerator opening setting process is terminated. The acceleration suppression state is a state in which the movable piece 37 is in the second position and the second contact 33 and the output side contact 35 are connected.

Therefore, when the acceleration suppression state is in effect, the relay switch 15 is in the on state as shown in FIG. 4, and the accelerator opening represented by the output signal is the second accelerator opening. Therefore, when the acceleration suppression state is in effect, the driving force control unit 11 controls the driving force of the vehicle according to the second accelerator opening. Because the second accelerator opening is 0%, the vehicle does not accelerate when in the acceleration suppression state.

Next, in S140, it is determined whether the vehicle is currently in an acceleration suppression state. If it is determined in S140 that the vehicle is in an acceleration suppression state, the process proceeds to S150, and if it is determined in S140 that the vehicle is not in an acceleration suppression state, the process proceeds to S190.

In S105, it is determined whether the following fourth condition is satisfied.
Fourth condition: the first accelerator opening is equal to or greater than a second reference opening that is set in advance for a predetermined period of time (e.g., 5 seconds) or more. The second reference opening is set to a larger opening than the first reference opening, e.g., 80% accelerator opening.

If the fourth condition is met, S150 determines that the driver intends to cancel the acceleration suppression state and proceeds to S160; if the fourth condition is not met, it proceeds to S170.

In S160, the vehicle state is shifted from the acceleration suppression state to the emergency escape state, and the accelerator opening setting process is terminated.
When the vehicle state transitions to an emergency escape state in this manner, the accelerator opening setting unit 61 performs switching control to periodically change the on/off state of the relay switch 15 by alternately switching the position of the movable piece 37 between the first position and the second position, as shown in FIG. 4.

Therefore, when the vehicle is in an emergency escape state, the vehicle can start and accelerate, but the acceleration of the vehicle is suppressed compared to when the vehicle is in a normal state.
In addition, in the emergency escape state, the control unit 50 executes the time ratio control process shown in FIG. 5 at predetermined time intervals to realize the function of the time ratio control unit 63 .

The time ratio control process is a process that sets the time ratio between the on time and the off time when switching the on/off state of the relay switch 15, in other words, the drive duty of the relay switch 15, according to the vehicle state. The time ratio control process will be explained in detail later.

Next, in S170, it is determined whether the normal transition condition is met. The normal transition condition is met when the following fifth condition is met and at least one of the following sixth conditions A to C is met.

Fifth condition: The first accelerator opening is equal to or smaller than a third reference opening that is set in advance. The third reference opening is set to an opening smaller than the first reference opening, for example, 10% of the accelerator opening.

Condition 6A: The obstacle detection unit 55 detects no obstacle in the traveling direction of the vehicle.
Condition 6B: The vehicle speed detected by the vehicle speed detection unit 57 using the vehicle speed sensor 7 is 0 km/h.

Condition 6C: The current shift position detected by the shift detection unit 59 via the shift sensor 9 is different from the shift position detected immediately before transition to the acceleration suppression state.
If it is determined in S170 that the normal transition condition is met, the process proceeds to S180, and if it is determined in S170 that the normal transition condition is not met, the accelerator opening setting process is terminated.

In S180, as shown in FIG. 4, the relay switch 15 is turned off so that the first signal representing the first accelerator opening is output as an output signal to the driving force control unit 11, thereby transitioning the vehicle state to the normal state and terminating the accelerator opening setting process.

Next, in S190, it is determined whether a preset time has elapsed since the vehicle entered an emergency escape state. This time is set to, for example, 5 to 10 seconds. Therefore, the vehicle remains in an emergency escape state for 5 to 10 seconds, and the accelerator opening represented by the output signal is alternately switched between the first accelerator opening and the second accelerator opening, suppressing acceleration of the vehicle.

If it is determined in S190 that a preset time has elapsed since the vehicle entered an emergency escape state, the process proceeds to S180, where the vehicle state is returned to the normal state and the accelerator opening setting process is terminated.

Also, if it is determined in S190 that a preset time has not elapsed since the vehicle entered the emergency escape state, the process proceeds to S170. Therefore, even if the predetermined time has not elapsed since the vehicle entered the emergency escape state, it is determined in S170 whether the normal transition condition is met, and if the normal transition condition is met, the vehicle state is transitioned to the normal state in S180.

As described above, when the vehicle transitions from the acceleration suppression state to the normal state, the accelerator opening setting process places the vehicle in an emergency escape state for a predetermined time. In the emergency escape state, the accelerator opening represented by the output signal is alternately switched between the first accelerator opening and the second accelerator opening by switching control.

However, when the vehicle is in an emergency escape state, if the time ratio for alternating between the first accelerator opening and the second accelerator opening represented by the output signal is fixed, the vehicle acceleration will change depending on the type of vehicle, vehicle condition, surrounding environment, etc.

Therefore, in this embodiment, when the vehicle is in an emergency escape state, the control unit 50 executes the time ratio control process shown in Figure 5 to adjust the time ratio for switching the on/off state of the relay switch 15 so that the vehicle is accelerated at the desired acceleration.
[Time ratio control process]
As shown in Figure 5, in the time ratio control process, first in S210, it is determined whether the time ratio control process is the first process to be performed after the vehicle state changes from an acceleration suppression state to an emergency escape state, in other words, whether it is the first emergency escape process.

If it is determined in S210 that the time ratio control process is the first emergency escape process, the process proceeds to S220. If it is determined in S210 that the time ratio control process is not the first emergency escape process, the process proceeds to S230.

In S220, a preset initial value is set as the on/off time of the relay switch 15, and the process proceeds to S290. In S290, the on-time guard process is executed to limit the on-time of the relay switch 15 to within a preset upper and lower limit time, and the time ratio control process is terminated.

The time ratio control process is repeated at predetermined time intervals, and from the second time after the emergency escape state is reached, the on-time of the relay switch 15 is updated in the process from S230 onwards. Therefore, in S290, the on-time is updated to limit the on-time to within the upper and lower limit times so that it does not exceed a preset upper limit time or fall below a preset lower limit time.

When the on/off times are set to their initial values in S220, the on time will not exceed the upper limit or fall below the lower limit, so the on time will not be limited in S290.

As a result, during the first cycle T of the switching control from time t1 to time t2 shown in FIG. 4, the relay switch 15 is in the OFF state for the OFF time corresponding to the initial value, and then in the ON state for the ON time corresponding to the initial value.

Therefore, in the initial switching control, the relay switch 15 is turned on and off at a preset time ratio, and an output signal representing the first accelerator opening and an output signal representing the second accelerator opening are output in sequence.

The period T of the switching control of the relay switch 15 is set according to the response speed at which the relay switch 15 can be stably switched between on and off, and is, for example, several ms to several hundred ms.

Next, in S230, the vehicle body acceleration is calculated based on the vehicle speed detected by the vehicle speed detection unit 57, and the process proceeds to S240.
In S240, it is determined whether or not it is currently time to update the on-time of the relay switch 15. This update timing is set in synchronization with the switching control, and is set to occur every cycle of the switching control, for example, every time t2, t3, t4, ... shown in Fig. 4, immediately after the vehicle enters the emergency escape state. This update timing is changed depending on the acceleration state of the vehicle. This point will be described later.

If it is determined in S240 that it is now time to update the on-time, the process proceeds to S250, and if it is determined in S240 that it is not now time to update the on-time, the process proceeds to S290.

In S250, it is determined whether the vehicle body acceleration is equal to or greater than a preset first acceleration X1. If it is determined in S250 that the vehicle body acceleration is equal to or greater than the first acceleration X1, the process proceeds to S280. If it is determined in S250 that the vehicle body acceleration is less than the first acceleration X1, the process proceeds to S260.

In S260, it is determined whether the vehicle body acceleration is equal to or less than a preset second acceleration X2. The second acceleration X2 is set to an acceleration smaller than the first acceleration X1. If it is determined in S260 that the vehicle body acceleration is equal to or less than the second acceleration X2, the process proceeds to S270. If it is determined in S260 that the vehicle body acceleration exceeds the second acceleration X2, the process proceeds to S290.

In S270, because the vehicle body acceleration is equal to or less than the second acceleration X2, in order to increase the vehicle body acceleration, the time ratio of the on/off time of the relay switch 15 is updated by subtracting a preset correction time Y1 from the current on time Ton of the relay switch 15. Then, once the on time Ton has been updated in this way in S270, the process proceeds to S290.

In addition, in S270, the on time Ton of the relay switch 15 is shortened, and therefore the proportion of time during which the output signal representing the first accelerator opening is output from the relay switch 15 increases. Then, the process of S270 is repeatedly executed until the vehicle body acceleration reaches the second acceleration X2.

As a result, as shown in FIG. 6, the ratio of the on time Ton of the relay switch 15 gradually decreases from when the vehicle enters an emergency escape state until the vehicle body acceleration reaches the second acceleration X2. As a result, the acceleration of the vehicle is promoted, and the vehicle body acceleration reaches the second acceleration X2 more quickly.

In addition, if it is determined in S260 that the vehicle body acceleration exceeds the second acceleration X2, the process of S270 is not executed and the on time Ton of the relay switch 15 is maintained. However, even in this state, the vehicle body acceleration gradually increases and reaches the first acceleration X1.

When the vehicle body acceleration reaches the first acceleration X1, at the next on-time update timing, S250 determines that the vehicle body acceleration is equal to or greater than the first acceleration X1, and the process of S280 is executed.

In S280, since the vehicle body acceleration is equal to or greater than the first acceleration X1, in order to suppress the acceleration of the vehicle, the time ratio of the on/off time of the relay switch 15 is updated by adding a preset correction time Y2 to the current on time Ton of the relay switch 15.

The correction time Y2 is set to a time shorter than the correction time Y1 used until the time t10 at which the vehicle body acceleration reaches the second acceleration X2 in S270. For example, the correction time Y2 is set to 16 ms, and the correction time Y1 is set to 32 ms.

This is because the vehicle is accelerating from a stopped state until time t10 when the vehicle body acceleration reaches the second acceleration X2, so the vehicle is accelerated more quickly and the vehicle body acceleration is prevented from fluctuating significantly thereafter.

The on-time update in S280 is repeated until the vehicle body acceleration becomes less than the first acceleration X1. As a result, as shown in FIG. 6, after time t11 when the vehicle body acceleration reaches the first acceleration X1, the increase in the vehicle body acceleration is suppressed and the vehicle body acceleration gradually decreases.

Then, thereafter, when the vehicle body acceleration becomes equal to or less than the second acceleration X2, the process of S270 is performed, and when the vehicle body acceleration becomes equal to or greater than the first acceleration X1, the process of S280 is performed. Note that, at time t10, when the vehicle body acceleration exceeds the second acceleration X2 once and then becomes equal to or less than the second acceleration X2, that is, for example, after time t13 illustrated in FIG. 6, in S270, the on-time is updated with the same correction time Y2 as in S280.

As a result, when the vehicle is in an emergency escape state, the correction time is changed between up to time t11, when the vehicle body acceleration first reaches the first acceleration X1, and after time t11, and the correction time for the on-time Ton is shortened after time t11. Therefore, the vehicle body acceleration is more likely to converge to within the target range between the first acceleration X1 and the second acceleration X2.

In this embodiment, the update timing determined in S240 is changed between before time t11 and after time t11, and is set to occur once every two periods of the switching control after time t11. Therefore, after time t11, the update frequency of the on-time Ton decreases, and fluctuations in the vehicle acceleration due to the update of the on-time Ton can be suppressed.
[effect]
As described above, in the vehicle control device of this embodiment, when the vehicle state becomes an emergency escape state and the accelerator opening setting unit 61 starts switching control, the time ratio for switching the accelerator opening is controlled by the time ratio control process.

Then, in the time ratio control process, the on-time of the relay switch 15 as an output unit is updated so that the vehicle acceleration falls within a target range between the first acceleration X1 and the second acceleration X2.

Therefore, according to the vehicle control device of this embodiment, when the vehicle is in an emergency escape state, the vehicle acceleration is suppressed from changing depending on the type of vehicle, etc., and the vehicle can be accelerated at a substantially constant acceleration. Therefore, when the vehicle is in an emergency escape state, the sense of acceleration given to the occupants can be made substantially constant regardless of the type of vehicle, etc., and the sense of anxiety caused by the fluctuation in the sense of acceleration can be suppressed.

In addition, in this embodiment, the correction time Y of the on-time Ton used to control the time ratio for switching the accelerator opening and the update period of the on-time Ton are changed according to the vehicle state. Specifically, the correction time Y and the update period are changed depending on whether the vehicle is accelerating from a stopped state or after the vehicle body acceleration has reached the target acceleration (first and second accelerations X1 and X2) due to the acceleration.

Therefore, when the vehicle is accelerating from a stopped state, the vehicle can be accelerated more quickly, and thereafter, the vehicle body acceleration can be converged to within the target range more quickly while suppressing fluctuations in the vehicle body acceleration.
[Other embodiments]
Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments and can be implemented in various modified forms.

For example, in the above embodiment, the vehicle body acceleration is calculated based on the vehicle speed, but it may be detected using an acceleration sensor.
In addition, the correction amount (i.e., correction time Y) of the time ratio for switching the accelerator opening when the vehicle is in an emergency escape state, such as the correction times Y1 and Y2 of the on time Ton in the above embodiment, may be corrected according to not only the acceleration state of the vehicle but also the road surface condition and the surrounding environment.

In addition, the road surface condition can be determined by parameters that affect the vehicle acceleration, such as the road surface inclination angle and friction coefficient. In addition, the surrounding environment can be determined by weather conditions that affect the vehicle acceleration, such as rainfall and snowfall.

Furthermore, the update timing for correcting the time ratio (i.e., the update period) may be set according to not only the acceleration state of the vehicle but also the road surface state and the environmental state.
The correction time and the update period may be appropriately changed depending on whether the vehicle is an engine vehicle using an engine as a power source, a hybrid vehicle using an engine and a motor as a power source, etc. In other words, these parameters may be adapted according to the type of vehicle.

In addition, the initial values of the on/off times set in S220 and the upper and lower limits of the on time updated in S270 and S280 may be adapted according to the type of vehicle.

In this way, when the vehicle is in an emergency escape state, the vehicle can be accelerated at a more appropriate acceleration rate.
In the above embodiment, the relay switch 15 is used to alternately switch the output signal to the driving force control unit 11 between a first signal representing the first accelerator opening and a second signal representing the second accelerator opening. However, a switch circuit such as a semiconductor switch capable of switching the signal path at higher speed may be used instead of the relay switch 15. In this way, the output signal output to the driving force control unit 11 can be a third signal between the first signal and the second signal by the switching operation of the switch circuit.

Furthermore, multiple functions possessed by one component in the above embodiments may be realized by multiple components, or one function possessed by one component may be realized by multiple components. Further, multiple functions possessed by multiple components may be realized by one component, or one function realized by multiple components may be realized by one component. Further, part of the configuration of the above embodiments may be omitted. Further, at least part of the configuration of the above embodiments may be added to or substituted for the configuration of another of the above embodiments.

In addition to the vehicle control device described above, the present disclosure can also be realized in various forms, such as a system that includes the vehicle control device as a component, a program for causing a computer to function as a control unit of the vehicle control device, a non-transient physical recording medium such as a semiconductor memory on which the program is recorded, a vehicle control method, etc.

15... relay switch, 41, 45... signal lines, 55... obstacle detection unit, 57... vehicle speed detection unit, 59... shift detection unit, 61... accelerator opening setting unit, 63... time ratio control unit.

Claims (3)

A vehicle control device that controls a vehicle,
an output unit (15, 45) configured to output an output signal representing an accelerator opening to a driving force control unit that controls the driving force of the vehicle in accordance with an accelerator opening;
a first accelerator opening acquisition unit (15, 41) configured to acquire a first accelerator opening representing an amount of depression of an accelerator pedal from an accelerator pedal sensor;
an obstacle detection unit (55) configured to detect an obstacle present in the direction of travel of the vehicle;
a vehicle speed detection unit (57) configured to detect a vehicle speed of the vehicle;
an accelerator opening setting unit (61) configured to set an accelerator opening represented by the output signal;
Equipped with
The accelerator opening setting unit is
when the accelerator opening represented by the output signal is the first accelerator opening, if an acceleration suppression condition is established in which the obstacle is detected by the obstacle detection unit, the first accelerator opening is equal to or greater than a predetermined first reference opening, and the vehicle speed detected by the vehicle speed detection unit is equal to or less than a predetermined reference vehicle speed, the accelerator opening represented by the output signal is switched to a second accelerator opening smaller than the first accelerator opening,
when the accelerator opening represented by the output signal is the second accelerator opening and the first accelerator opening is equal to or greater than a preset second reference opening continuously for a predetermined period of time or more, a switching control is implemented to alternately switch the accelerator opening represented by the output signal between the first accelerator opening and the second accelerator opening at a predetermined cycle,
when a preset time has elapsed since the start of the switching control, the accelerator opening represented by the output signal is switched to the first accelerator opening.
It is structured as follows:
a time ratio control unit (63) for changing a time ratio between the first accelerator opening degree and the second accelerator opening degree, which are alternately switched when the accelerator opening degree setting unit is performing the switching control, in accordance with an acceleration of the vehicle,
The time ratio control unit
Calculating the acceleration based on the vehicle speed detected by the vehicle speed detection unit or a signal from an acceleration sensor;
updating the time ratio at an update timing synchronized with a switching operation of the accelerator opening in the switching control so that a time ratio during which an output signal representing the first accelerator opening is output increases when the acceleration is equal to or less than a second acceleration (X2) that is smaller than a first acceleration (X1);
When the acceleration is equal to or greater than the first acceleration, the time ratio is updated at the update timing so that the time ratio during which the output signal representing the first accelerator opening is output is reduced.
It is structured as follows:
Furthermore, in this vehicle control device, a correction time for increasing the time ratio from when the time ratio control unit starts control for updating the time ratio as the accelerator opening setting unit starts the switching control until the acceleration exceeds the second acceleration is set to a time longer than the correction time for updating the time ratio thereafter. 2. The vehicle control device according to claim 1, wherein a period of the update timing at which the time ratio control unit updates the time ratio from when the time ratio control unit starts update control of the time ratio as the accelerator opening setting unit starts the switching control until the acceleration reaches the second acceleration is set to a period shorter than a period of the update timing at which the time ratio control unit thereafter updates the time ratio. 3. The vehicle control device according to claim 1, wherein in the time ratio control unit, an initial value and upper and lower limit values are set for the time ratio updated at the update timing, and the time ratio control unit updates the time ratio within a range of the upper and lower limit values.

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