阅读说明：本技术 车辆的控制装置 (Vehicle control device ) 是由 筱原俊太郎 北川裕康 大坪秀显 牟田浩一郎 藤竹良德 平田拓也 目次宏光 于 2020-04-09 设计创作，主要内容包括：本发明的课题为,与加速踏板的踩下操作相对应,不使驾驶员感到不适或冲击地对车辆的驱动力恰当地进行控制。本发明的车辆的控制装置,相对于加速踏板开度的输入值,根据基于设有规定的滞后的输入输出特性计算出的输出值,对驱动力源进行控制,其中,由不灵敏区和渐近区域形成所述滞后的幅度,所述不灵敏区是对应于所述输入值的变化、所述输出值不发生变化的区域,所述渐近区域超出所述不灵敏区,是对应于所述输入值的变化、所述输出值基于由曲线表示的规定的函数而连续地变化的区域,在所述输入值在所述不灵敏区的范围内变化的情况下,不使所述输出值变化,在所述输入值超出所述不灵敏区而增大的情况下,使所述输出值基于所述函数而增大(步骤S5),在所述输入值超出所述不灵敏区而减小的情况下,使所述输出值基于所述函数而减小(步骤S9)。(The object of the present invention is to appropriately control the driving force of a vehicle without causing discomfort or impact to the driver in response to the depression operation of an accelerator pedal. The vehicle control device of the present invention controls a driving force source based on an output value calculated based on an input-output characteristic provided with a predetermined hysteresis with respect to an input value of an accelerator opening degree, wherein a width of the hysteresis is formed by a dead zone which is a zone in which the output value does not change in accordance with a change in the input value and a gradual-up zone which is a zone in which the output value does not change in accordance with a change in the input value and in which the output value continuously changes in accordance with a predetermined function represented by a curve in accordance with a change in the input value, the output value is not changed when the input value changes within a range of the dead zone, the output value is increased in accordance with the function when the input value increases in accordance with the increase in accordance with the input value exceeding the dead zone (step S5), and the drive force source is controlled based on the output value calculated in accordance with the input-output characteristic provided with the predetermined hysteresis, the output value is decreased based on the function (step S9).)

1. A control device for a vehicle, comprising a driving force source, an accelerator pedal, a detection unit for detecting an operation amount of the accelerator pedal by a driver, and a controller for calculating an output value of the operation amount based on an input-output characteristic obtained by providing a predetermined delay to an input value of the operation amount detected by the detection unit and controlling the driving force source based on the output value,

a magnitude of the hysteresis in a direction of change of the input value is formed of an insensitive region which is a region where the output value does not change or changes by a slight change amount that is not felt by the driver in correspondence with a change of the input value, and an asymptotic region which is a region where the output value continuously changes based on a prescribed function represented by a plurality of straight lines or curves in correspondence with a change of the input value that exceeds the insensitive region,

the controller stores the input-output characteristic, the insensitive region, and the asymptotic region,

the controller does not change the output value or increases the output value by the minute change amount when the input value increases within the range of the dead zone, and does not change the output value or decreases the output value by the minute change amount when the input value decreases within the range of the dead zone,

the controller increases the output value based on the function when the input value increases beyond the insensitive area, and decreases the output value based on the function when the input value decreases beyond the insensitive area.

2. The control apparatus of a vehicle according to claim 1,

the insensitive region has: a 1 st dead zone in which the output value does not change or increases by the minute amount of change when the input value increases, and at least one of a 2 nd dead zone in which the output value does not change or decreases by the minute amount of change when the input value decreases,

the asymptotic region has: at least one of a 1 st asymptotic region in which the output value increases based on the function if the input value increases beyond the 1 st insensitive region, and a 2 nd asymptotic region in which the output value decreases based on the function if the input value decreases beyond the 2 nd insensitive region.

3. The control apparatus of a vehicle according to claim 2,

the 1 st asymptotic region is set to: the more the operation amount increases, the greater the rate of change in the output value with respect to the input value in the 1 st progressive region becomes.

4. The control apparatus of a vehicle according to claim 2,

the 2 nd asymptotic region is set to: the rate of change in the output value with respect to the input value in the 2 nd progressive region becomes larger as the operation amount decreases.

Background

Patent document 1 describes a throttle valve control device that controls the opening degree of a throttle valve provided in an engine for a vehicle. The throttle control device described in patent document 1 controls the opening degree of the throttle valve based on an acceleration request operation by the driver, that is, an operation amount of a depression operation of an accelerator pedal by the driver. Further, a delay is provided between a direction in which the amount of operation of the accelerator pedal increases and a direction in which the amount of operation of the accelerator pedal decreases. The hysteresis in this case is set such that the hysteresis width is narrower when the amount of operation of the accelerator pedal is large, as compared with the case where the amount of operation of the accelerator pedal is small.

In the pedal device described in patent document 2, a delay is provided in the relationship between the depression force when the driver operates the accelerator pedal and the vehicle output (the driving force of the vehicle). A part of the relationship between the pedaling force and the vehicle output in the depressing operation or the retracting operation is set to be represented by a straight line (linear line) or a broken line.

In the pedal device described in patent document 3, a hysteresis and a dead zone are provided in a relationship between a depression force and a vehicle output when a driver operates an accelerator pedal. The relationship between the stepping force and the vehicle output in the stepping-on operation and the retracting operation of the accelerator pedal is set to be different from each other. In the accelerator pedal holding operation, the relationship is set such that the vehicle output has a constant inclination with respect to the stepping force.

In both of the pedal devices described in patent documents 2 and 3, the driving force of the vehicle is controlled based on the depression force when the driver depresses the accelerator pedal. In general, an accelerator pedal is configured to return a depressed pedal to an origin by a biasing force of a spring. Therefore, the pedal devices described in patent documents 2 and 3 have hysteresis due to the structure of the accelerator pedal including a spring. This hysteresis is a characteristic in which the hysteresis width becomes larger as the tread force is larger. The tread force of the accelerator pedal generally becomes large in proportion to the operation amount of the accelerator pedal. Therefore, as the structural hysteresis of the accelerator pedal as described above, the hysteresis width becomes larger as the operation amount of the accelerator pedal is larger.

In the vehicle driving force control device described in patent document 4, the hysteresis is set so that the delay is different between when the amount of operation of the accelerator pedal is increased and when the amount of operation of the accelerator pedal is decreased, with respect to the relationship between the amount of operation of the accelerator pedal and the control amount (required driving force) for reflecting the amount of operation on the driving force. When the change speed of the accelerator pedal operation amount is high, the change width of the control amount with respect to the change width of the accelerator pedal operation amount is larger than that when the change speed of the accelerator pedal operation amount is low. The above-described hysteresis is set so that the required driving force becomes sluggish with respect to the operation amount of the accelerator pedal. In other words, the operation amount of the accelerator pedal used in the control is passivated in the direction of the time axis. Therefore, inevitably, a feeling of stagnation of time is generated with respect to the operation of the driver.

[ Prior art documents ]

[ patent document ]

Patent document 1: japanese examined patent publication (Kokoku) No. 7-68924

Patent document 2: japanese patent laid-open publication No. 2006-283561

Patent document 3: japanese patent laid-open publication No. 2006-281810

Patent document 4: japanese patent No. 5157834

Disclosure of Invention

Problems to be solved by the invention

As in the control device described in patent document 1, when the output of the engine or the driving force of the vehicle is controlled in accordance with the depression operation of the accelerator pedal, usually, hysteresis is intentionally provided in order to prevent fluctuation of the control. For example, as shown in fig. 1, the hysteresis is set between an input value of the operation amount of the accelerator pedal and an output value output in accordance with the input value. In the example shown in fig. 1, the output value of the accelerator pedal opening degree does not change in any case with respect to an increase in the input value of the accelerator pedal opening degree (operation amount) shown in the section from the point a to the point b and a decrease in the input value of the accelerator pedal opening degree shown in the section from the point c to the point d. Therefore, a portion corresponding to the magnitude of the hysteresis (the magnitude of the hysteresis in the direction of change in the input value of the accelerator pedal opening degree) in the example shown in fig. 1 becomes a so-called dead zone. By providing such a hysteresis and dead zone, fluctuations and oscillations in the control can be suppressed.

However, when the driving force of the vehicle is controlled based on the relationship between the input value and the output value of the depression operation of the accelerator pedal as shown in patent document 1 or fig. 1, there is a risk that the driver feels uncomfortable or it is difficult to maintain the operation amount of the accelerator pedal. For example, when the driver performs a depressing operation on the accelerator pedal from the input value I1 to the input value I2 in fig. 1, the output value corresponding to the input value of the amount of the depressing operation is bounded by the point b in fig. 1, and the amount of change thereof changes abruptly (starts to change). As a result, the driving force of the vehicle controlled according to the output value of the operation amount may be abruptly changed, and the driver may feel discomfort or impact due to the change in the driving force. For example, when the driver holds the operation amount of the accelerator pedal in the vicinity of the input value I3 in fig. 1, or when the driver operates the accelerator pedal with a slight operation amount, the output value changes in a manner oscillating between the step-on side and the retraction side with respect to a slight change in the input value of the operation amount of the accelerator pedal in fig. 1. As a result, the driving force of the vehicle controlled according to the output value of the operation amount becomes unstable.

As described above, there is still room for improvement in order to satisfactorily achieve both natural operation characteristics that do not cause discomfort or impact to the driver and stability in maintaining the operation of the accelerator pedal when controlling the driving force or acceleration of the vehicle in accordance with the depression operation of the accelerator pedal by the driver.

The present invention has been made in view of the above-described technical problem, and an object thereof is to provide a vehicle control device that can smoothly and stably control the driving force or acceleration of a vehicle without causing a driver to feel discomfort or impact when controlling the driving force or acceleration of the vehicle in accordance with the depression operation of an accelerator pedal by the driver.

Means for solving the problems

In order to achieve the above object, a control device for a vehicle according to the present invention includes a drive power source, an accelerator pedal, a detection unit that detects an operation amount of the accelerator pedal by a driver, and a controller that calculates an output value of the operation amount based on an input-output characteristic obtained by providing a predetermined hysteresis to an input value of the operation amount detected by the detection unit and controls the drive power source based on the output value, wherein a magnitude of the hysteresis in a change direction of the input value is formed by a dead zone in which the output value does not change or changes by a minute amount of change that is not felt by the driver in accordance with a change of the input value and an asymptotic zone in which the output value continuously changes in accordance with a change of the input value that exceeds the dead zone in accordance with a predetermined function represented by a plurality of straight lines or curved lines And a field in which the controller stores the input/output characteristic, the dead zone, and the asymptotic field, wherein the controller does not change the output value or increases the output value by the small change amount when the input value increases within the range of the dead zone, does not change the output value or decreases the output value by the small change amount when the input value decreases within the range of the dead zone, increases the output value based on the function when the input value increases beyond the dead zone, and decreases the output value based on the function when the input value decreases beyond the dead zone.

In addition, the present invention is characterized in that the dead zone in the present invention has: a 1 st dead zone in which the output value does not change or increases by the minute amount of change when the input value increases, and at least one of a 2 nd dead zone in which the output value does not change or decreases by the minute amount of change when the input value decreases, the asymptotic region in the present invention has: at least one of a 1 st asymptotic region in which the output value increases based on the function if the input value increases beyond the 1 st insensitive region, and a 2 nd asymptotic region in which the output value decreases based on the function if the input value decreases beyond the 2 nd insensitive region.

In addition, the present invention is characterized in that the 1 st asymptotic region in the present invention is set to: the more the operation amount increases, the greater the rate of change in the output value with respect to the input value in the 1 st progressive region becomes.

Further, according to the present invention, the 2 nd asymptotic region in the present invention is set to: the rate of change in the output value with respect to the input value in the 2 nd progressive region becomes larger as the operation amount decreases.

ADVANTAGEOUS EFFECTS OF INVENTION

The control device of a vehicle of the present invention controls a driving force source based on a driver's depression operation of an accelerator pedal. In this case, the operation amount during the depressing operation of the accelerator pedal is detected, and the output value of the operation amount of the accelerator pedal is calculated based on a predetermined input-output characteristic with respect to the detected value of the operation amount, that is, the input value of the operation amount of the accelerator pedal. Then, the output of the driving force source, that is, the driving force or acceleration of the vehicle is controlled in accordance with the calculated output value. Hysteresis is set in the input-output characteristics of the operation amount of the accelerator pedal, thereby suppressing hunting or hunting in controlling the drive power source based on the output value. Further, in the vehicle control device according to the present invention, the hysteresis in the input-output characteristic is formed by combining a dead zone and an asymptotic region. The fluctuation or oscillation of the control as described above can be suppressed by the dead zone. In the asymptotic region, the output value is calculated so as to continuously change smoothly in accordance with the change in the input value with respect to the amount of operation of the accelerator pedal. Therefore, by controlling the output of the driving force source using the output value of the operation amount of the accelerator pedal, the output of the driving force source can be continuously and smoothly controlled in accordance with the change in the input value of the operation amount of the accelerator pedal. In addition, when the operation amount of the accelerator pedal is maintained, the output of the drive force source corresponding thereto can be stably maintained. Therefore, according to the vehicle control device of the present invention, the driving force or acceleration of the vehicle can be smoothly and stably controlled without causing discomfort or impact to the driver.

Further, according to the control device for a vehicle of the present invention, the dead zone and the asymptotic zone as described above are set in both the depression side and the retraction side in the depression operation of the accelerator pedal by the driver. Therefore, the driving force or acceleration of the vehicle can be appropriately controlled in either a case where the driver depresses the accelerator pedal or a case where the driver retracts the accelerator pedal, or a case where the driver repeats the depression and retraction by a minute operation amount.

Further, according to the control device of the vehicle of the present invention, the rate of change (i.e., the slope) of the output value with respect to the input value in the 1 st progressive region is set to be larger as the operation amount of the accelerator pedal increases in the case where the driver depresses the accelerator pedal. Specifically, for example, in a rectangular coordinate system having the horizontal axis as an input value and the vertical axis as an output value, the 1 st progressive region is set as indicated by a curve having a shape convex downward (toward the side where the output value is small). Therefore, when the driver depresses the accelerator pedal, the output value of the operation amount increases with respect to the depression operation (input value of the operation amount) from a state in which there is no reaction to the depression operation, and the amount of change in the output value per unit operation amount gradually increases as the driver depresses the accelerator pedal. Therefore, the output of the driving force source can be continuously and smoothly increased in accordance with the depressing operation of the accelerator pedal. In addition, when the operation amount is held in the middle of the depression operation of the accelerator pedal, the output of the drive force source corresponding thereto can be stably held.

Further, according to the control device of the vehicle of the present invention, the rate of change (i.e., the slope) of the output value with respect to the input value in the 2 nd progressive region is set to be larger as the operation amount of the accelerator pedal is smaller in the case where the driver retracts the accelerator pedal. Specifically, for example, in a rectangular coordinate system having the horizontal axis as an input value and the vertical axis as an output value, the 2 nd progressive area is set as indicated by a curve having a shape convex upward (the side on which the output value is large). Thus, at the time of the retraction operation of the accelerator pedal by the driver, the decrease in the output value of the operation amount with respect to the retraction operation (the input value of the operation amount) gradually becomes larger as the driver retracts the accelerator pedal from the state in which there is little reaction with respect to the retraction operation. Therefore, the output of the drive power source can be continuously and smoothly reduced in correspondence with the retracting operation of the accelerator pedal. In addition, when the operation amount is held in the middle of the retracting operation of the accelerator pedal, the output of the drive power source corresponding thereto can be stably held.

Drawings

Fig. 1 is a diagram for explaining a problem in the conventional art, and is a diagram showing input/output characteristics of an accelerator pedal opening degree provided with hysteresis.

Fig. 2 is a diagram showing an example of a configuration and a control system of a vehicle as a control target in the vehicle control device according to the present invention.

Fig. 3 is a block diagram for explaining a control system of a vehicle as a control target in the control device of the vehicle of the present invention.

Fig. 4 is a flowchart for explaining an example of control performed by the vehicle control device of the present invention.

Fig. 5 is a diagram for explaining input/output characteristics of an accelerator pedal opening degree in control performed by the vehicle control device according to the present invention, and shows an example of input/output characteristics (an example in which a step-on side and a step-off side are symmetrically set) of an accelerator pedal opening degree provided with a lag formed by a "dead zone" and a "progressive zone".

Fig. 6 is a diagram for explaining the input/output characteristics of the accelerator pedal opening degree in the control performed by the vehicle control device according to the present invention, and is a diagram showing another example (an example in which the step-on side and the retraction side are set asymmetrically) of the input/output characteristics of the accelerator pedal opening degree in which a hysteresis formed by the "dead zone" and the "asymptotic region" is provided.

Fig. 7 is a diagram for explaining the input/output characteristics of the accelerator pedal opening degree in the control performed by the vehicle control device according to the present invention, and is a diagram showing another example of the input/output characteristics of the accelerator pedal opening degree in which a hysteresis formed by the "dead zone" and the "asymptotic region" is provided (an example in which the hysteresis width on the retraction side is formed only by the "dead zone").

Fig. 8 is a diagram for explaining the input/output characteristics of the accelerator pedal opening degree in the control performed by the vehicle control device according to the present invention, and is a diagram showing another example of the input/output characteristics of the accelerator pedal opening degree in which a hysteresis formed by the "dead zone" and the "asymptotic region" is provided (an example in which the hysteresis width on the retracting side is formed by only the "asymptotic region").

Detailed Description

Embodiments of the present invention are explained with reference to the drawings. The embodiments described below are merely examples of embodying the present invention, and are not intended to limit the present invention.

Fig. 2 shows an example of a drive system and a control system of a vehicle Ve to be controlled in the embodiment of the present invention. A vehicle Ve shown in fig. 2 is equipped with a drive power source (PWR)1, an accelerator pedal 2, a detection portion 3, and a controller (ECU)4 as main components.

The driving force source 1 is a power source that outputs driving torque for running the vehicle Ve. The driving force source 1 is an internal combustion engine such as a gasoline engine or a diesel engine, and is configured to electrically control an operation state such as adjustment of an output and start and stop of the engine. In the case of a gasoline engine, the opening degree of a throttle valve, the amount of fuel supplied or injected, the ignition timing, and the like are electrically controlled. Alternatively, in the case of a diesel engine, the fuel injection amount, the fuel injection timing, the opening degree of a throttle valve in an EGR system, and the like are electrically controlled.

The driving force source 1 according to the embodiment of the present invention may be a permanent magnet type synchronous motor, an induction motor, or the like. The motor in this case may be, for example, a so-called motor generator having both a function as a prime mover driven by the supplied electric power to output a motor torque and a function as a generator driven by the received external torque to generate electric power. In the case of a motor generator, the rotation speed or torque is electrically controlled, or the function as a prime mover and the function as a generator are switched.

The vehicle Ve transmits the drive torque output from the drive force source 1 to the drive wheels to generate drive force. Fig. 2 shows a front wheel drive vehicle in which the front wheels 5 serve as drive wheels. The vehicle Ve according to the embodiment of the present invention may be a rear-wheel drive vehicle in which the rear wheels 6 serve as drive wheels. Alternatively, a four-wheel drive vehicle may be used in which both the front wheels 5 and the rear wheels 6 are used as drive wheels. When an engine is mounted as drive power source 1, a transmission (not shown) may be provided on the output side of the engine, and drive torque output from drive power source 1 may be transmitted to the drive wheels via the transmission.

The vehicle Ve has a conventional configuration, and the driving force or acceleration of the vehicle Ve is controlled based on the operation amount of the acceleration request operation by the driver and the vehicle speed. For example, a target acceleration based on the operation amount of the acceleration request operation and the vehicle speed is set, and the output of the drive power source 1 is controlled so as to achieve the target acceleration. Thus, the vehicle Ve has an accelerator pedal 2 for an acceleration request operation by the driver. When the driver depresses the accelerator pedal 2, that is, performs an acceleration request operation, the torque output from the drive force source 1 increases in accordance with an increase in the operation amount (depression amount) of the accelerator pedal 2, and the drive force of the vehicle Ve increases. Conversely, by retracting the depression of the accelerator pedal 2, the torque output from the drive force source 1 is reduced in accordance with the reduction of the operation amount of the accelerator pedal 2, and the drive force of the vehicle Ve is reduced.

As described above, the accelerator pedal 2 adjusts the driving force of the vehicle Ve by the acceleration request operation of the driver, and controls the acceleration of the vehicle Ve. Therefore, the accelerator pedal 2 is provided with an accelerator position sensor 3a for detecting the amount of operation of the accelerator pedal 2 by the driver, as will be described later. The Accelerator Position sensor 3a can detect the operation amount of the Accelerator pedal 2 (Accelerator opening, depression angle, Accelerator Position). Further, the operating speed of the accelerator pedal 2 can be calculated from the detected operating amount of the accelerator pedal 2. By obtaining the operating speed of the accelerator pedal 2, the operating state and the operating direction of the accelerator pedal 2 by the driver can be determined. That is, it is possible to determine whether or not the accelerator pedal 2 is depressed by the driver, or whether or not the accelerator pedal 2 is depressed and retracted by the driver.

The detection portion 3 is a member that obtains various data for controlling the vehicle Ve, and particularly detects various data relating to the operation amount of the accelerator pedal 2. The detection unit 3 is a generic term for a sensor or an instrument for detecting such various data. Accordingly, the detection unit 3 in the embodiment of the present invention includes at least an accelerator position sensor 3a that detects an operation amount of the accelerator pedal 2 (hereinafter, referred to as an accelerator pedal opening degree). The detection unit 3 includes, for example, a wheel speed sensor 3b for detecting a vehicle speed, an acceleration sensor 3c for detecting an acceleration in a front-rear direction of the vehicle Ve, a rotational speed sensor 3d for detecting a rotational speed of an output shaft (not shown) of the drive force source 1, a brake stroke sensor 3e for detecting an operation amount of a brake pedal (not shown), and the like. The detection unit 3 is electrically connected to a controller 4 described later, and outputs an electric signal corresponding to a detection value of the various sensors, instruments, and the like as described above to the controller 4 as detection data.

The controller 4 is an electronic control device mainly composed of a microcomputer, for example. Various data detected by the detection unit 3 as described above are input to the controller 4. The controller 4 performs an operation using various data to be input, and data, a formula, and the like stored in advance. At the same time, the calculation result is output as a control command signal to control the vehicle Ve.

Specifically, as shown in fig. 3, the controller 4 includes an arithmetic unit 4a and a control unit 4 b. For example, the arithmetic unit 4a acquires various data including the accelerator pedal opening detected by the accelerator position sensor 3 a. At the same time, the computing unit 4a calculates a target acceleration or a target driving torque of the vehicle Ve based on the acquired various data. On the other hand, the control unit 4b controls the longitudinal acceleration of the vehicle Ve based on the target acceleration or the target drive torque calculated by the calculation unit 4 a. That is, a control command signal for controlling the driving force to achieve the target acceleration is output.

Accordingly, the controller 4 sets a target acceleration based on the detected accelerator pedal opening degree, and controls the driving force and the braking force of the vehicle Ve so as to achieve the target acceleration. Specifically, the output of the driving force source 1 is controlled. Although fig. 2 shows an example in which one controller 4 is provided, a plurality of controllers 4 may be provided for each device or instrument to be controlled or each control content. For example, as shown in fig. 3, the controller 4 may be a main controller that comprehensively controls the vehicle Ve, and a controller (power train ECU)7 that controls the drive power source 1, the transmission, and the like exclusively in cooperation with the controller 4 may be provided separately.

As described above, the control device for a vehicle according to the embodiment of the present invention is configured to satisfactorily achieve both natural operation characteristics that do not cause the driver to feel discomfort or impact and stability in maintaining the operation of the accelerator pedal 2 when controlling the driving force or acceleration of the vehicle Ve in accordance with the depression operation of the accelerator pedal 2 by the driver. An example of control performed by the controller 4 in the vehicle control device is shown in the flowchart of fig. 4.

When the accelerator pedal 2 is operated by the driver, the control shown in the flowchart of fig. 4 is performed. First, in step S1, the input value θ i of the accelerator pedal opening at this time is obtained. Specifically, the current accelerator opening detected by the accelerator position sensor 3a is input to the controller 4 as the current input value θ i.

Next, in step S2, it is determined whether or not the current input value θ i of the accelerator pedal opening is larger than the previous input value θ i-1 of the accelerator pedal opening. For example, the input value θ of the accelerator pedal opening degree obtained before 1 cycle of the process shown in the flowchart of fig. 4 is the input value θ i-1 of the accelerator pedal opening degree at the previous time. Alternatively, when the accelerator pedal opening degree is detected at predetermined time intervals, the detected value that is earlier than the latest detected value (i.e., the input value θ i of the accelerator pedal opening degree of this time) is the input value θ i-1 of the accelerator pedal opening degree of the previous time. In short, in step S2, it is determined whether the currently performed operation of the accelerator pedal 2 is a depressing operation for increasing the accelerator opening or a retracting operation for decreasing the accelerator opening.

If the input value θ i of the current accelerator pedal opening is larger than the input value θ i-1 of the previous accelerator pedal opening, that is, the driver' S operation of the accelerator pedal 2 is the depressing operation of the accelerator pedal 2, and an affirmative determination is made in step S2, the routine proceeds to step S3.

In step S3, it is determined whether or not the input value θ i of the accelerator opening degree of this time is within the range of the depression-side dead zone (1 st dead zone) 1. In the control device for a vehicle according to the embodiment of the present invention, the input/output characteristic of the accelerator opening degree is set. The input-output characteristic of the accelerator opening defines a relationship between an input value θ and an output value η of the accelerator opening detected by the accelerator position sensor 3 a. The input value θ of the accelerator opening degree is detected by the accelerator position sensor 3a, and is data relating to the operation amount of the accelerator pedal 2 input to the controller 4. The output value η of the accelerator opening degree is data calculated by performing an operation based on the input/output characteristics of the accelerator opening degree on the input value θ of the accelerator opening degree input to the controller 4, and is data output as a control command signal from the controller 4 in order to control the drive force source 1. As shown in fig. 5, the input-output characteristic of the accelerator opening degree is provided with a predetermined delay between the depression side and the retraction side of the accelerator pedal 2. Fig. 5 shows a rectangular coordinate system with the horizontal axis as an input value θ and the vertical axis as an output value η. In the hysteresis according to the embodiment of the present invention, the width in the direction of change of the input value θ i of the accelerator opening degree (hysteresis width α) is formed by the dead zone and the asymptotic region γ.

The dead-zone is a region in which the output value η of the accelerator pedal opening is not changed or the output value η is slightly changed by a slight change amount to the extent that the driver cannot feel, in accordance with a change in the input value θ of the accelerator pedal opening. In addition, the insensitive region has a 1 st insensitive region 1 and a 2 nd insensitive region 2. The 1 st dead zone 1 is a dead zone (depression-side dead zone 1) employed when the driver depresses the accelerator pedal 2, that is, when the input value θ of the accelerator pedal opening degree increases. The 2 nd dead zone 2 is a dead zone (the retraction-side dead zone 2) employed when the driver retracts the accelerator pedal 2, that is, when the input value θ of the accelerator pedal opening degree decreases.

The asymptotic region γ is a region outside the dead zone as described above, and is a region in which the input value θ of the accelerator opening degree changes and the output value η of the accelerator opening degree changes continuously based on a predetermined function represented by a plurality of straight lines or curves in accordance with the change in the input value θ of the accelerator opening degree. In the example shown in fig. 5, the asymptotic region γ is defined by a curve such as a quadratic function, a fractional function, an exponential function, a logarithmic function, or a trigonometric function. In addition, the asymptotic region γ has a 1 st asymptotic region γ 1 and a 2 nd asymptotic region γ 2. The 1 st asymptotic region γ 1 is an asymptotic region γ (a depression-side asymptotic region γ 1) employed when the driver depresses the accelerator pedal 2, that is, when the input value θ of the accelerator pedal opening increases beyond the depression-side dead zone 1. The 2 nd asymptotic region γ 2 is an asymptotic region γ (the retraction-side asymptotic region γ 2) employed when the driver retracts the accelerator pedal 2, that is, when the input value θ of the accelerator pedal opening degree decreases beyond the retraction-side insensitive region 2.

The above-mentioned insensitive region and asymptotic region γ are continuously and smoothly connected. That is, the 1 st dead zone (step-on side dead zone) 1 and the 1 st asymptotic region (step-on side asymptotic region) γ 1 are continuously and smoothly connected. Further, the 2 nd dead zone (retraction side dead zone) 2 and the 2 nd asymptotic region (retraction side asymptotic region) γ 2 are continuously and smoothly connected.

If an affirmative determination is made in step S3 because the input value θ i of the present accelerator pedal opening degree is within the range of the depression-side dead zone 1, the routine proceeds to step S4.

In step S4, the output value η i-1 of the accelerator pedal opening at the previous time is replaced with the output value η i of the accelerator pedal opening at the next time. In this case, the accelerator opening degree that is changed by the depressing operation of the accelerator pedal 2 is limited to a slight change within the range of the depression-side dead zone 1. Thus, the output value η i-1 of the accelerator opening degree is held with respect to the input value θ i of the accelerator opening degree. That is, in this case, the output value η of the accelerator pedal opening is not changed in accordance with the change of the input value θ of the accelerator pedal opening.

On the other hand, if the input value θ i of the present accelerator opening degree is increased beyond the range of the depression-side dead zone 1 and a negative determination is made in step S3, the routine proceeds to step S5.

In step S5, an output value η i corresponding to the input value θ i of the current accelerator opening degree is obtained. For example, the output value η i is calculated based on a function F1(x) that defines a curve of the 1 st asymptotic region γ 1 as shown in fig. 5. The output value η i can be calculated by substituting the input value θ i into the variable x of the function F1 (x). As described above, the function F1(x) is a predetermined function having a curved portion on a graph, such as a quadratic function, a fractional function, an exponential function, a logarithmic function, or a trigonometric function. The function F1(x) is set in advance so as to obtain an appropriate slope and curvature by, for example, a driving experiment or simulation. In the example shown in fig. 5, for example, a curve of the 1 st asymptotic region γ 1 is defined using a fractional function as the function F1 (x).

As described above, the input-output characteristic of the accelerator pedal opening degree in the embodiment of the invention is provided with a hysteresis having the hysteresis width α in the direction of change of the input value θ i. The hysteresis is formed by the dead zone and the asymptotic region γ, and particularly, as shown in fig. 5, the hysteresis in the input/output characteristic of the accelerator pedal opening degree at the step-down side is formed by the 1 st dead zone 1 and the 1 st asymptotic region γ 1. The 1 st asymptotic region γ 1 is represented by a curve having a shape convex downward (on the side where the output value η is small), as shown in fig. 5. In other words, the 1 st asymptotic region γ 1 is set to: in the case where the driver depresses the accelerator pedal 2, the rate of change of the output value η with respect to the input value θ in the 1 st asymptotic region γ 1 (i.e., the slope of the curve representing the 1 st asymptotic region γ 1 in fig. 5) becomes larger as the operation amount of the accelerator pedal 2 increases. Therefore, when the driver depresses the accelerator pedal 2, the amount of change in the output value η per unit operation amount gradually increases as the driver depresses the accelerator pedal 2 from a state in which the output value η of the operation amount increases with respect to the input value θ of the accelerator opening degree, which does not respond to the depression operation. Therefore, according to the control device for a vehicle in the embodiment of the present invention, the driving force of the vehicle Ve can be continuously and smoothly increased in accordance with the depression operation of the accelerator pedal 2 by the driver. Further, when the driver holds the operation amount in the middle of the depressing operation of the accelerator pedal 2, the driving force of the vehicle Ve corresponding thereto can be stably held.

When the output value η i of the current accelerator pedal opening degree is obtained in either step S4 or step S5, the routine proceeds to step S6.

In step S6, the output value η i-1 of the accelerator pedal opening degree at the previous time is updated to the output value η i at the present time. The previous input value θ i-1 of the accelerator pedal opening degree is updated to the current input value θ i. Thereafter, the process shown in the flowchart of fig. 4 is temporarily ended.

On the other hand, if a negative determination is made in step S2 because the current input value θ i of the accelerator pedal opening is smaller than the previous input value θ i-1 of the accelerator pedal opening, that is, the driver' S operation of the accelerator pedal 2 is a retracting operation of the accelerator pedal 2, the routine proceeds to step S7.

In step S7, it is determined whether or not the input value θ i of the present accelerator pedal opening degree is within the range of the retraction-side dead zone (2 nd dead zone) 2.

If an affirmative determination is made in step S7 because the input value θ i of the present accelerator pedal opening degree is within the range of the retraction-side dead zone 2, the routine proceeds to step S8.

In step S8, the output value η i-1 of the previous accelerator pedal opening degree is replaced with the output value η i of the present accelerator pedal opening degree. In this case, the accelerator opening degree that is changed by the retracting operation of the accelerator pedal 2 is limited to a slight change within the range of the 2 nd dead zone 2. Therefore, the output value η i-1 of the accelerator opening degree is held with respect to the input value θ i of the accelerator opening degree. That is, in this case, the output value η of the accelerator pedal opening is not changed in accordance with the change of the input value θ of the accelerator pedal opening.

On the other hand, if the input value θ i of the present accelerator opening degree is increased beyond the range of the retraction-side dead zone 2 and a negative determination is made in step S7, the routine proceeds to step S9.

In step S9, an output value η i corresponding to the input value θ i of the current accelerator opening degree is obtained. For example, the output value η i is calculated based on a function F2(x) that defines a curve of the 2 nd asymptotic region γ 2 as shown in fig. 5. The output value η i can be calculated by substituting the input value θ i into the variable x of the function F2 (x). As described above, the function F2(x) is a predetermined function having a curved portion on a graph, such as a quadratic function, a fractional function, an exponential function, a logarithmic function, or a trigonometric function. The function F2(x) is set in advance so as to obtain an appropriate slope and curvature by, for example, a driving experiment or simulation. In the example shown in fig. 5, for example, a curve of the 2 nd asymptotic region γ 2 is defined using a fractional function as the function F2 (x).

As described above, fig. 5 shows an example of input/output characteristics in which the accelerator pedal opening degrees on the depression side and the retraction side are set symmetrically. By symmetrically setting the depression side and the retraction side as shown in fig. 5, the accelerator pedal 2 can be operated with the same feeling when the driver depresses the accelerator pedal 2 and when retracting the accelerator pedal 2. Therefore, the operation of the vehicle Ve can be easily performed. On the other hand, the input-output characteristic of the accelerator pedal opening in the embodiment of the present invention does not necessarily have to be a symmetric relationship between the depression side and the retraction side. For example, as shown in fig. 6, the input/output characteristics may be such that the accelerator pedal opening degrees on the depression side and the retraction side are set asymmetrically. For example, the input/output characteristics may be such that the accelerator opening degrees on the depression side and the retraction side are set independently and appropriately according to the characteristics of the vehicle Ve, the characteristics of the driving operation of the driver, and the like.

The "dead zone" of the input/output characteristic of the accelerator pedal opening degree in the embodiment of the present invention has at least one of the "1 st dead zone 1" on the depression side and the "2 nd dead zone 2" on the retraction side as described above. In the embodiment of the present invention, the "asymptotic region γ" of the input/output characteristic of the accelerator pedal opening degree has at least one of the "1 st asymptotic region γ 1" on the stepped-down side and the "2 nd asymptotic region γ 2" on the retraction side as described above. Accordingly, in the vehicle control device according to the embodiment of the present invention, for example, as shown in fig. 7, the input/output characteristics of the accelerator pedal opening degree may be such that the "1 st dead zone 1" and the "1 st progressive region γ 1" form the hysteresis width α on the stepping-in side, and the "2 nd dead zone 2" forms the hysteresis width α on the retracting side. Alternatively, as shown in fig. 8, the input/output characteristic of the accelerator pedal opening degree may be such that the retard width α on the step-down side is formed by the "1 st dead zone 1" and the "1 st progressive zone γ 1" and the retard width α on the retraction side is formed only by the "2 nd progressive zone γ 2". Alternatively, although not shown, the input/output characteristic of the accelerator pedal opening degree may be such that the retard width α on the step-down side is formed only by the "1 st dead zone 1" and the retard width α on the retraction side is formed by the "2 nd dead zone 2" and the "2 nd asymptotic region γ 2". Alternatively, although not shown in the drawings, the input/output characteristic of the accelerator pedal opening degree may be such that the retard width α on the step-down side is formed only by the "1 st progressive region γ 1" and the retard width α on the retraction side is formed by the "2 nd dead zone 2" and the "2 nd progressive region γ 2".

As described above, the input-output characteristic of the accelerator pedal opening degree in the embodiment of the invention is provided with a hysteresis having the hysteresis width α in the direction of change of the input value θ i. The hysteresis is formed by the dead zone and the asymptotic region γ, and particularly, as shown in fig. 5, the hysteresis in the input/output characteristic of the accelerator opening degree on the retracting side is formed by the 2 nd dead zone 2 and the 2 nd asymptotic region γ 2. The 2 nd asymptotic region γ 2 is represented by a curve having a convex shape upward (the side where the output value η is large) as shown in fig. 5. In other words, the 2 nd asymptotic region γ 2 is set to: in the case where the driver retracts the accelerator pedal 2, the rate of change of the output value η with respect to the input value θ in the 2 nd asymptotic region γ 2 (i.e., the slope of the curve representing the 2 nd asymptotic region γ 2 in fig. 5) becomes larger the smaller the operation amount of the accelerator pedal 2. Thus, when the driver performs the retracting operation of the accelerator pedal 2, the decrease of the output value η of the operation amount with respect to the input value θ of the operation amount gradually increases the amount of change in the output value η per unit operation amount as the driver retracts the accelerator pedal 2 from the state in which there is little reaction with respect to the retracting operation. Therefore, according to the control device of the vehicle in the embodiment of the invention, the driving force of the vehicle Ve can be continuously and smoothly reduced in correspondence with the retracting operation of the accelerator pedal 2 by the driver. Further, when the driver holds the operation amount in the middle of the retracting operation of the accelerator pedal 2, the driving force of the vehicle Ve corresponding thereto can be stably held.

When the output value η i of the current accelerator pedal opening degree is obtained in either step S8 or step S9, the routine proceeds to step S6.

In step S6, the output value η i-1 of the previous accelerator pedal opening degree is updated to the current output value η i as in the previous case. Further, the input value θ i-1 of the accelerator pedal opening degree at the previous time is updated to the input value θ i at the present time. Then, the process shown in the flowchart of fig. 4 is temporarily ended.

As described above, the control device of the vehicle in the embodiment of the present invention controls the driving force source 1 based on the driver's depression operation of the accelerator pedal 2. In this case, an accelerator opening degree, which is an operation amount during the depressing operation of the accelerator pedal 2, is detected, and an output value η of the accelerator opening degree is calculated based on a predetermined input-output characteristic with respect to an input value θ of the accelerator opening degree, which is a detection value of the accelerator opening degree. Then, the output of the driving force source 1, that is, the driving force or acceleration of the vehicle Ve is controlled in accordance with the calculated output value η. A hysteresis is set in the input-output characteristic of the accelerator opening degree, thereby suppressing hunting or hunting when driving force source 1 is controlled based on output value η.

Further, in the control device for a vehicle according to the embodiment of the present invention, the hysteresis in the input-output characteristic is formed by combining the dead zone and the asymptotic region γ. The dead zone can suppress the fluctuation or oscillation of the control as described above. In the asymptotic region γ, the output value η is calculated so as to continuously and smoothly change with respect to a change in the input value θ of the accelerator opening degree. Therefore, by controlling the output of drive power source 1 using output value η of the accelerator opening degree, the output of drive power source 1 can be continuously and smoothly controlled in accordance with the change in input value θ of the accelerator opening degree. In addition, when the accelerator opening degree is maintained, the output of the driving force source 1 corresponding thereto can be stably maintained. Therefore, according to the control device for a vehicle in the embodiment of the present invention, the driving force or acceleration of the vehicle Ve can be smoothly and stably controlled without causing discomfort or impact to the driver.

Description of the reference numerals

1 … driving force source (PWR), 2 … accelerator pedal, 3 … detecting part, 3a … accelerator position sensor, 3b … wheel speed sensor, 3c … brake stroke sensor, 3d … acceleration sensor, 3e … rotational speed sensor, 4 … controller (ECU), 4a … (of controller) computing part, 4b … (of controller) controlling part, 5 … front wheel, 6 … rear wheel, 7 … controller (power train ECU), Ve … vehicle power train ECU