JP2010228651A - Accelerator pedal reaction force imparting device for vehicle and method used for the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To transmit a desired additional reaction force to a driver from an accelerator pedal even when relation between the accelerator pedal and the foot of the driver is varied during operation of the accelerator pedal. <P>SOLUTION: An accelerator pedal reaction force imparting device for a vehicle includes: a spring 6 for making an outer force to be imparted in the step-returning direction of the accelerator pedal larger in a case where the depressed amount of the accelerator pedal 100 operated by the treading force of the driver is large than in a case where the depressed amount of the accelerator pedal 100 is small; an accelerator pedal actuator 5 for imparting the outer force in the step-returning direction of the accelerator pedal 100 based on a traveling situation; an accelerator pedal operation amount sensor 3 for detecting the operation of the accelerator pedal 100; and a target pedal additional reaction force calculating part 23 for carrying out correction to make the outer force imparted by the accelerator pedal actuator 5 larger, in a case where the depressed amount of the accelerator pedal detected by the accelerator pedal operation amount sensor 3 is small, than in a case where the depressed amount of the accelerator pedal 100 is large. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a technique for controlling a reaction force of an accelerator pedal operated by a driver's pedaling force.

The accelerator pedal of a vehicle is usually applied with a larger reaction force as the amount of depression is larger. For example, such a reaction force (normal reaction force) is generated by a spring or the like.
On the other hand, in Patent Document 1, a reaction force (additional reaction force) corresponding to the traveling state of the vehicle is applied to the accelerator pedal separately from the reaction force due to the spring or the like. In Patent Document 1, when the host vehicle speed is equal to or higher than a predetermined set speed, an additional reaction force is applied to the accelerator pedal to notify the driver that the host vehicle speed has exceeded the set speed.

JP 2003-260951 A

By the way, during the operation of the accelerator pedal, the way in which the accelerator pedal and the driver's foot are involved may change. In such a case, there is a problem that the desired additional reaction force cannot be transmitted from the accelerator pedal to the driver simply by determining the additional reaction force according to the traveling state of the vehicle as in Patent Document 1.
An object of the present invention is to transmit a desired additional reaction force from the accelerator pedal to the driver even if the manner in which the accelerator pedal and the driver's foot change during operation of the accelerator pedal changes.

In order to solve the above-mentioned problem, the present invention provides an external force applied in the accelerator pedal depressing direction when the accelerator pedal is depressed by a driver's pedaling force more than when the accelerator pedal is depressed less. Increase
Further, the present invention applies an external force in the stepping-back direction of the accelerator pedal based on the traveling situation.
In the present invention, when the amount of depression of the accelerator pedal is small, correction is made to increase the external force to be applied based on the traveling state, compared to when the amount of depression of the accelerator pedal is large.

According to the present invention, the amount of depression of the accelerator pedal is reduced, and the manner in which the accelerator pedal is engaged with the driver's foot changes. Usually, the additional reaction force transmitted from the accelerator pedal to the driver is reduced. The correction is made so as to increase the external force to be applied based on the traveling situation, compared to when the amount of depression of the accelerator pedal is large.
As a result, even if the relationship between the accelerator pedal and the driver's foot changes during the operation of the accelerator pedal, the correction is made to increase the external force applied based on the driving situation. Can be transmitted to the driver from the accelerator pedal.

It is a figure which shows the structure of the accelerator pedal reaction force provision apparatus for vehicles of embodiment mounted in the vehicle. It is a block diagram which shows the structure of the accelerator pedal reaction force provision apparatus for vehicles. It is a block diagram which shows the structure of a controller. It is a figure which shows the structural example of an accelerator pedal actuator. It is a flowchart which shows the process sequence of inter-vehicle maintenance support control in a controller. It is a characteristic view which shows the characteristic of a pre reaction force. It is a characteristic view which shows the characteristic of this reaction force. It is a characteristic view which shows the relationship between an accelerator opening and an accelerator opening dependence gain. It is a figure which shows an example of a time-dependent change which shows the change of an accelerator pedal reaction force (pre reaction force or this reaction force). The state where the suspension type accelerator pedal is stepped on with a foot is shown. It is a figure which shows the change of the arm length (reaction force action point) when operating an accelerator pedal. It is a characteristic view which shows the relationship between an accelerator opening and arm length. It is a figure which shows the relationship between arm length and the reaction force in a reaction force action point. It is a characteristic view which shows the relationship between an accelerator opening and pedal effort in the measurement point which fixed the pad position of the accelerator pedal (fixed reaction force action point). The figure shows a state where an organ type accelerator pedal is being stepped on with a foot. FIG. 5 is a relationship diagram showing hysteresis characteristics of accelerator pedal stroke and accelerator pedal depression force. FIG. 17 is a relationship diagram for determining a threshold value APS1 of an accelerator pedal stroke APS that increases the depression force on the depression side of the accelerator pedal shown in FIG.

(Constitution)
This embodiment is a vehicle accelerator pedal reaction force applying device to which the present invention is applied. In this embodiment, the accelerator pedal reaction force applying device for a vehicle realizes inter-vehicle maintenance support control.
FIG.1 and FIG.2 shows the structure of the accelerator pedal reaction force provision apparatus for vehicles. FIG. 1 shows the configuration of a vehicular accelerator pedal reaction force applying device mounted on a vehicle. FIG. 2 is a block diagram of the accelerator pedal reaction force applying device for a vehicle.

As shown in FIGS. 1 and 2, the accelerator pedal reaction force applying device for a vehicle includes a laser radar 1, a vehicle speed sensor 2, an accelerator pedal operation amount sensor 3, a controller 20, an accelerator pedal reaction force control device 4, and an accelerator pedal actuator 5. Have
The laser radar 1 scans infrared light pulses in the horizontal direction and the vertical direction in front of the vehicle. That is, the laser radar 1 scans infrared light pulses in a predetermined area on the front, the left, and right in front of the vehicle. For example, the region scanned by the laser radar 1 is a region having a predetermined angle (for example, about ± 10 °) with respect to the front of the vehicle. The vehicle includes a laser radar 1 in a front grill part or a bumper part. The laser radar 1 measures a reflected wave of an infrared light pulse reflected by a front object. The forward object is, for example, a forward vehicle (preceding vehicle), and the laser radar 1 measures the reflected wave of the infrared light pulse reflected at the rear end of the forward vehicle.

  Then, the laser radar 1 detects the inter-vehicle distance from the own vehicle to the front object and the presence direction of the front object with respect to the own vehicle based on the arrival time and the emission direction of the reflected wave with respect to the emitted infrared light pulse. To do. The presence direction of the front object is information indicated as a relative angle with respect to the host vehicle. Further, when there are a plurality of front objects (front vehicles), the inter-vehicle distance and the existence direction of the plurality of front objects are detected. The laser radar 1 outputs the detected inter-vehicle distance and existing direction (in some cases, a plurality of inter-vehicle distances and existing directions) to the controller 20 as front object information.

In the present embodiment, a laser radar is described as an example. However, the present invention is also applicable to a sound wave radar that emits sound waves and acquires front object information based on reflected waves with respect to the emitted sound waves.
The vehicle speed sensor 2 detects the vehicle speed. The vehicle speed sensor 2 detects the vehicle speed based on, for example, a wheel speed sensor. For example, the vehicle speed sensor 2 detects the vehicle speed based on the wheel speed of the driven wheel and the average value of the wheel speeds of the front and rear wheels. The vehicle speed sensor 2 outputs the detected own vehicle speed to the controller 20.

The accelerator pedal operation amount sensor 3 detects the operation amount of the accelerator pedal of the driver from the accelerator opening. The accelerator pedal operation amount sensor 3 outputs the detected operation amount of the accelerator pedal to the controller 20.
The controller 20 controls the entire accelerator pedal reaction force applying device for a vehicle. FIG. 3 shows the configuration of the controller 20. As shown in FIG. 3, the controller 20 includes an obstacle recognition unit 21, an inter-vehicle distance threshold calculation unit 22, and a target pedal additional reaction force calculation unit 23. As shown in FIG. 3, the front object information (the distance between vehicles, the direction of existence, etc.) and the host vehicle speed are input to the controller 20.

The obstacle recognition unit 21 detects an obstacle situation around the host vehicle (particularly in front of the host vehicle) based on the input forward object information and the host vehicle speed. The obstacle recognition unit 21 outputs the detected obstacle situation around the host vehicle to the inter-vehicle distance threshold calculation unit 22.
The inter-vehicle distance threshold value calculation unit 22 calculates the inter-vehicle distance threshold value based on the inputted obstacle situation around the host vehicle. Specifically, the inter-vehicle distance threshold calculation unit 22 calculates a first inter-vehicle distance threshold and a second inter-vehicle distance threshold. The calculation procedure of the first inter-vehicle distance threshold and the second inter-vehicle distance threshold by the inter-vehicle distance threshold calculating unit 22 will be described in detail later. The inter-vehicle distance threshold calculation unit 22 outputs the calculated inter-vehicle distance threshold (the first inter-vehicle distance threshold and the second inter-vehicle distance threshold) to the target pedal additional reaction force calculation unit 23.

  The target pedal additional reaction force calculation unit 23 calculates a target pedal additional reaction force based on the input inter-vehicle distance threshold (the first inter-vehicle distance threshold and the second inter-vehicle distance threshold). The target pedal additional reaction force calculation unit 23 calculates a reaction force command value for controlling the force applied to the accelerator pedal as the target pedal additional reaction force. The target pedal additional reaction force (reaction force command value) is a control command value that drives the accelerator pedal reaction force control device 4 in order to cause the accelerator pedal to generate a target reaction force value.

Further, the accelerator pedal operation amount detected by the accelerator pedal operation amount sensor 3 is input to the target pedal additional reaction force calculation unit 23. The target pedal additional reaction force calculation unit 23 corrects the target pedal additional reaction force (reaction force command value) based on the input accelerator pedal operation amount.
The target pedal additional reaction force calculation unit 23 outputs the calculated (corrected) target pedal additional reaction force to the accelerator pedal reaction force control device 4.

The accelerator pedal reaction force control device 4 is based on a target pedal additional reaction force (corrected target pedal additional reaction force) output from the controller 20 (target pedal additional reaction force calculation unit 23), and an accelerator pedal actuator based on a drive signal. 5 controls the torque (external force applied to the accelerator pedal) generated by the accelerator 5.
FIG. 4 shows a configuration example of the accelerator pedal actuator 5. The accelerator pedal 100 is a lifting type accelerator pedal. The accelerator pedal 100 includes an arm portion 101 whose one end portion (support portion) 101a is rotatably supported by the vehicle body, and a pedal portion (pad portion) 102 attached to the other end of the arm portion 101.

  The accelerator pedal actuator 5 is disposed between the arm portion 101 of the accelerator pedal 100 and the vehicle body floor 110. The accelerator pedal actuator 5 is driven by a motor to expand and contract. The accelerator pedal actuator 5 extends to increase the target pedal additional reaction force (reaction force command value), and operates to push the arm portion 101 toward the driver. Therefore, in relation to the accelerator pedal operation amount, the arm part 101 is pushed out more toward the driver as the accelerator pedal depressing amount is larger.

The accelerator pedal reaction force control device 4 controls the driver's stepping force on the accelerator pedal 100 by generating a reaction force on the accelerator pedal 100 by driving the accelerator pedal actuator 5 as described above.
Further, as shown in FIG. 4, the elastic body 6 is disposed between the arm portion 101 of the accelerator pedal 100 and the vehicle body floor 110 to generally generate a reaction force. For example, the elastic body 6 includes a spring and a spring.

  As shown in FIG. 4, the accelerator pedal operation amount sensor 3 detects the rotational position of the accelerator pedal 100 from the operation part (for example, a drive member) of the accelerator pedal actuator 5. That is, the operation part of the accelerator pedal actuator 5 and the depression amount (operation amount) of the accelerator pedal 100 are uniquely associated, and the accelerator pedal operation amount sensor 3 is based on the operation part of the accelerator pedal actuator 5. The pedal rotation position is detected. The accelerator pedal operation amount sensor 3 outputs the detected rotation position of the accelerator pedal to the controller 20.

FIG. 5 shows a processing procedure of the inter-vehicle maintenance support control in the controller 20. The controller 20 performs this process at regular intervals (for example, 10 msec). Along with the description of the processing procedure of FIG. 5, the processing of each component of the controller 20 will be described in more detail.
As shown in FIG. 5, first, in step S1, the obstacle recognition unit 21 reads the running state data. The traveling state data is data on a state relating to traveling including an obstacle state ahead of the host vehicle and a traveling state of the host vehicle. Specifically, the obstacle recognition unit 21 reads the front object information detected by the laser radar 1 and the own vehicle speed detected by the vehicle speed sensor 2.

Subsequently, in step S2, the obstacle recognition unit 21 performs an obstacle recognition process. Specifically, the obstacle recognition unit 21 recognizes the state of the front object based on the running state data read in step S1.
Here, based on the driving state data read in step S1 before the previous processing cycle and the driving state data read in step S1 in the current processing cycle, the relative position of the front object with respect to the host vehicle, Recognize the direction or speed of movement. Specifically, the obstacle recognizing unit 21 reads the relative position, moving speed, or direction of the front object with respect to the host vehicle read in step S1 and stored in a memory (not shown) before the previous processing cycle. And the relative position, moving speed, or existence direction of the front object with respect to the host vehicle read in step S1 in the current processing cycle. The obstacle recognizing unit 21 recognizes the relative position, moving speed, or moving direction of the front object currently detected based on the comparison result.

Based on the recognition result, the obstacle recognizing unit 21 arranges (relatively arranges) the front object in front of the own vehicle, and moves (relatively moves) the front object with respect to the own vehicle. Recognize what you are doing.
Subsequently, in step S3 and step S4, the inter-vehicle distance threshold calculation unit 22 calculates a first inter-vehicle distance threshold and a second inter-vehicle distance threshold.
Specifically, the inter-vehicle distance threshold value calculation unit 22 uses the following equation (1) to calculate the first inter-vehicle distance threshold value L1 and the relative speed Vr and the vehicle speed Vp of the preceding vehicle (front object) and A second inter-vehicle distance threshold L2 is set.
L1, L2 = f (Vsp, Vr, Vp) (1)

  Here, f is a function for calculating the first inter-vehicle distance threshold L1 and the second inter-vehicle distance threshold L2 based on the variables Vsp, Vr, Vp. Here, the variables Vsp, Vr, and Vp are different values when the first inter-vehicle distance threshold L1 is calculated and when the second inter-vehicle distance threshold L2 is calculated. Accordingly, the first inter-vehicle distance threshold L1 and the second inter-vehicle distance threshold L2 can be calculated separately based on the function f. At this time, the condition is that the first inter-vehicle distance threshold L1 is calculated to be smaller than the second inter-vehicle distance threshold L2 (L1 <L2).

  Subsequently, in step S5, the target pedal additional reaction force calculation unit 23 calculates a target pedal additional reaction force (reaction force command value) of the pre-reaction force based on the second inter-vehicle distance threshold L2 calculated in step S4. . Specifically, the target pedal additional reaction force calculation unit 23 calculates the target pedal additional reaction force τp of the pre-reaction force when the inter-vehicle distance L becomes smaller than the second inter-vehicle distance threshold L2 (L <L2). . That is, the target pedal additional reaction force calculation unit 23 determines that the running state of the host vehicle is in a high-risk state when the inter-vehicle distance L is smaller than the second inter-vehicle distance threshold L2 (L <L2). The target pedal additional reaction force τp of the pre-reaction force is calculated. Here, the target pedal additional reaction force τp is, for example, a value that realizes the reaction force of the accelerator pedal that enables the driver to maintain the inter-vehicle distance by the accelerator operation.

FIG. 6 shows a calculation result (pre-reaction force characteristic) of a specific pre-reaction force (target pedal additional reaction force τp). When the inter-vehicle distance L becomes smaller than the second inter-vehicle distance threshold L2 (L <L2), the target pedal additional reaction force calculating unit 23 starts calculating the pre-reaction force as shown in FIG. The pre-reaction force is increased to the reaction force C with an inclination (increase rate) c. The reaction force C constitutes an upper limit value of the pre-reaction force. Then, the target pedal additional reaction force calculation unit 23 holds the pre-reaction force at the reaction force C with the holding time t2, and after the holding time t2, the predetermined inclination (decrease rate) d (where | d | Pre-reaction force is reduced to reaction force D (<reaction force C) with <| c |).
Here, the reaction forces C and D and the inclinations c and d are values that allow the driver to recognize the pre-reaction force, for example, in a situation with a relatively large margin such that the driver maintains the inter-vehicle distance by an accelerator operation. It is. The holding time t2 is, for example, about 1 second.

  Subsequently, in step S6, the target pedal additional reaction force calculation unit 23 calculates the target pedal additional reaction force (reaction force command value) of the reaction force based on the first inter-vehicle distance threshold L1 calculated in step S3. . Specifically, the target pedal additional reaction force calculation unit 23 calculates the target pedal additional reaction force of the main reaction force when the inter-vehicle distance L becomes smaller than the first inter-vehicle distance threshold L1 (<L2) (L <L1). τm is calculated. Here, the target pedal additional reaction force τm is a value that realizes the reaction force of the accelerator pedal that supports the driver's switching operation from the accelerator pedal to the brake pedal. The target pedal additional reaction force τm of the main reaction force is generally larger than the target pedal additional reaction force τp of the pre-reaction force. That is, in this embodiment, this reaction force is made larger than the pre-reaction force. That is, the target pedal additional reaction force calculation unit 23 determines that the host vehicle has a vehicle distance L smaller than the first vehicle distance threshold L1 and that the vehicle distance L is smaller than the second vehicle distance threshold L2. It is determined that the running state of the vehicle is at a higher risk state, and the target pedal additional reaction force is increased.

FIG. 7 shows a calculation result (characteristic of the main reaction force) of a specific main reaction force (target pedal additional reaction force τm, reaction force command value). When the inter-vehicle distance L becomes smaller than the first inter-vehicle distance threshold L1 (L <L1), the target pedal additional reaction force calculation unit 23 starts calculating the reaction force as shown in FIG. The reaction force is increased to reaction force A with an inclination (increase rate) a. The reaction force A constitutes an upper limit value of the reaction force. Then, the target pedal additional reaction force calculation unit 23 holds the reaction force at the reaction force A with the holding time t1, and after the holding time t1, the inclination (decrease rate) b (where | b | <| a |) The reaction force is reduced to reaction force B (<A).
Here, the reaction force A is, for example, a magnitude that allows the driver to easily recognize the reaction force from the accelerator pedal. In addition, the slope a is a value that matches the speed of the accelerator pedal when the driver switches to the brake pedal (speed when returning). The holding time t1 is, for example, about 0.5 seconds.

Moreover, the target pedal additional reaction force calculation unit 23 calculates the reaction force B using the following equation (2).
Reaction force B = Reaction force A × ΔACC × K1 (2)
Here, K1 is a gain. The accelerator pedal depressing amount ΔACC is an accelerator pedal depressing amount starting from the time when the inter-vehicle distance L becomes smaller than the first inter-vehicle distance threshold L1. The starting point can also be set as the second inter-vehicle distance threshold L2. In this equation (2), the reaction force B decreases as the accelerator pedal depressing amount ΔACC increases. By calculating the reaction force B in this way, when the driver depresses the accelerator pedal by his / her own intention, the reaction force (reaction force B portion) is reduced.

  Subsequently, in step S7, the target pedal additional reaction force calculation unit 23 calculates a final target pedal additional reaction force (final reaction force command value). Specifically, the target pedal additional reaction force calculation unit 23 calculates the pre-reaction force target pedal additional reaction force τp (pre-reaction force reaction force command value) calculated in Step S5 and the main reaction calculated in Step S6. Select high from the target pedal additional reaction force τm (reaction force command value of this reaction force). Then, the target pedal additional reaction force calculation unit 23 uses the selected target pedal additional reaction force as the final target pedal additional reaction force τ (final reaction force command value).

Subsequently, in step S8, the target pedal additional reaction force calculation unit 23 corrects the final target pedal additional reaction force τ (final target pedal additional reaction force τ before correction) calculated in step S7. Specifically, the target pedal additional reaction force calculating unit 23 corrects the final target pedal additional reaction force τ using the following equation (3).
τ = τ × K2 (3)
Here, K2 is an opening-dependent gain corresponding to the accelerator opening (the amount of depression of the accelerator pedal). The accelerator opening dependent gain K2 decreases as the accelerator opening increases. In the equation (3), the final target pedal additional reaction force τ on the right side is a value before correction, and the final target pedal additional reaction force τ on the left side is a value after correction.

  FIG. 8 shows the relationship between the accelerator opening and the accelerator opening dependent gain K2. As shown in FIG. 8, the accelerator opening dependent gain K2 decreases as the accelerator opening increases. Further, the larger the accelerator opening, the larger the amount of change in the accelerator opening dependent gain K2 with respect to the change in the accelerator opening (the change rate becomes larger). When there is a relationship between the accelerator opening and the accelerator opening dependent gain K2, the final target pedal additional reaction force τ is corrected to a larger value as the accelerator opening is smaller.

The target pedal additional reaction force calculation unit 23 outputs the calculated final target pedal additional reaction force τ (the corrected final target pedal additional reaction force τ) to the accelerator pedal reaction force control device 4.
The accelerator pedal reaction force control device 4 is based on the corrected final target pedal additional reaction force τ (corrected final reaction force command value) calculated by the controller 20 (target pedal additional reaction force calculation unit 23) as described above. The torque generated by the accelerator pedal actuator 5 is controlled by the drive signal.

(Operation and action)
During traveling of the vehicle, the controller 20 reads the traveling state data during traveling of the vehicle and recognizes the state of the front object (steps S1 and S2).
Subsequently, the controller 20 calculates a target pedal additional reaction force τ based on the recognized state of the front object. That is, first, the controller 20 calculates the first inter-vehicle distance threshold and the second inter-vehicle distance threshold based on the host vehicle speed Vsp, the relative speed Vr, and the vehicle speed Vp of the preceding vehicle (front object) (steps S3 and S4). ). Further, the controller 20 calculates a target pedal additional reaction force τp (pre-reaction force reaction force command value) of the pre-reaction force based on the calculated second inter-vehicle distance threshold, and further calculates the calculated first inter-vehicle distance threshold. Based on this reaction force, a target pedal additional reaction force τm (reaction force command value of the main reaction force) is calculated (steps S5 and S6). Further, the controller 20 selects high the target pedal additional reaction force τp of the pre-reaction force and the target pedal additional reaction force τm of the main reaction force to obtain the final target pedal additional reaction force τ (final reaction force command value). (Step S7). Then, the controller 20 corrects the final target pedal reaction force τ based on the accelerator opening (step S8).
The accelerator pedal reaction force control device 4 controls the torque generated by the accelerator pedal actuator 5 based on the corrected final target pedal additional reaction force τ (corrected final reaction force command value) calculated by the controller 20.

(Relationship between pre reaction force and main reaction force)
FIG. 9 is an example showing a change in accelerator pedal reaction force with time. For example, this is a change in the accelerator pedal reaction force obtained when the inter-vehicle distance L decreases with time. With the select high, the accelerator pedal reaction force is either a pre-reaction force or a main reaction force.
As shown in FIG. 9, first, the vehicular accelerator pedal reaction force applying device generates a pre-reaction that generates a pre-reaction force as an accelerator pedal reaction force in a section where the inter-vehicle distance L is smaller than the second inter-vehicle distance threshold L2. Implement force control. The pre-reaction force at this time changes with time as shown in FIG.

  As a scene where the pre-reaction force is generated as the accelerator pedal reaction force, there is a scene in which the host vehicle approaches the vehicle ahead and the degree of approach is such that the driver maintains the inter-vehicle distance by the accelerator operation. In addition, the value of the inter-vehicle distance is set to the second inter-vehicle distance threshold when another vehicle interrupts in front of the host vehicle or when the other inter-vehicle distance control device (ACC, adaptive cruise control) is switched to this control device. It is a scene that suddenly interrupts L2. In such a case, the vehicular accelerator pedal reaction force applying device generates a pre-reaction force that can be recognized by the driver as the accelerator pedal reaction force.

And the accelerator pedal reaction force provision apparatus for vehicles starts calculation of this reaction force, when the inter-vehicle distance L becomes smaller than the 1st inter-vehicle distance threshold value L1. Thus, the vehicular accelerator pedal reaction force applying device generates the main reaction force as the accelerator pedal reaction force by the select high when the main reaction force obtained by the calculation becomes larger than the pre-reaction force. Implement force control. The reaction force (accelerator pedal reaction force) at this time changes with time as shown in FIG.
The scene in which this reaction force is generated as the accelerator pedal reaction force is a scene in which the host vehicle approaches the vehicle ahead and the degree of approach that requires the driver to perform a brake operation. In such a case, the reaction force that supports the driver's stepping operation from the accelerator pedal to the brake pedal is generated as the accelerator pedal reaction force.

(Correction of final target pedal additional reaction force τ)
In the present embodiment, correction is performed to increase the final target pedal additional reaction force τ (final reaction force command value) as the accelerator opening is smaller. Therefore, if the final target pedal additional reaction force τ is determined by the pre-reaction force, correction is made to increase the pre-reaction force, and the final target pedal additional reaction force τ is determined by the main reaction force. In this case, the correction is made to increase the reaction force.
Here, FIG. 10 shows a state where the suspension type accelerator pedal 100 is stepped on with a foot. As shown in FIG. 10, generally, the driver operates the accelerator pedal 100 by moving the foot so that the toe is rotated with the heel 201 of the foot 200 as a fulcrum. At this time, the sole and the pedal portion 102 of the accelerator pedal 100 may contact each other at a part (a point, a line, or a region) 300.

  FIG. 11 shows a state in which a portion (reaction force action point) 300 where the sole and the pedal portion of the accelerator pedal 100 are in contact with each other is changed by the operation of the accelerator pedal 100. As shown in FIG. 11, the reaction force action point 300 is changed by operating the accelerator pedal 100. Specifically, as the accelerator pedal 100 is stepped back (as the accelerator opening is closed), the arm length that is the distance between the rotation support point of the accelerator pedal 100 and the reaction force action point 300 becomes longer (from LA1). Changes to LA2). On the contrary, the arm length becomes shorter as the accelerator pedal 100 is depressed. In this way, the way the accelerator pedal 100 and the driver's foot are engaged changes during the operation of the accelerator pedal 100.

  FIG. 12 shows the relationship between the accelerator opening (stroke, accelerator pedal operation amount) and the arm length LA in the case shown in FIG. As shown in FIG. 12, the arm length LA becomes longer as the accelerator opening is smaller. More specifically, the smaller the accelerator opening, the greater the amount of change in the arm length LA with respect to the change in the accelerator opening (the change rate increases).

As described above, in the case of the suspension type accelerator pedal 100, the arm length becomes longer as the accelerator pedal 100 is stepped back, that is, as the amount of depression becomes smaller. This is because, when the output (reaction force command value) of the accelerator pedal actuator 5 for driving the accelerator pedal 100 is constant, the reaction force of the driver obtained from the accelerator pedal 100 is increased as the amount of depressing the accelerator pedal 100 is increased. Appears as a decrease in feeling.
Therefore, as shown in FIG. 12, when the accelerator opening is small, the amount of change in the arm length with respect to the change in the accelerator opening increases. If the accelerator opening is small, the reaction force feeling obtained from the accelerator pedal 100 is reduced. Decreases rapidly.

FIG. 13 shows the relationship between the arm length and the reaction force at the reaction force action point 300. As shown in FIG. 13, when the reaction force F1 is obtained with a certain arm length LA1, when the arm length LA2 is reached by depressing the accelerator pedal 100, the reaction force F2 also decreases accordingly. For example, the reaction force F2 can be expressed as the following equation (4).
F2 = F1 · LA1 / LA2 (4)

In contrast, in the present embodiment, the final target pedal additional reaction force τ is corrected to be larger as the accelerator opening is smaller. That is, the smaller the accelerator opening is, the larger the external force applied in the step-back direction of the accelerator pedal 100 by the accelerator pedal actuator 5 is corrected. As a result, even when the arm length becomes long when the accelerator pedal 100 is depressed, the reaction force transmitted to the driver via the reaction force action point on the long arm length is made constant or almost constant. Can do. As a result, it is possible to suppress a decrease in reaction feeling from the accelerator pedal 100 when the accelerator pedal 100 is stepped back. If it corresponds to the equation (4), the reaction force F2 at this time can be obtained as the following equation (5).
F2 = F1 ・ LA1 / LA2 ・ K3
K3 = LA2 / LA1
... (5)
Here, K3 is a correction gain. According to the equation (5), the reaction force F2 transmitted to the driver when the accelerator pedal 100 is stepped back is equal to the reaction force F1 transmitted to the driver before the accelerator pedal 100 is stepped back. .

This correction only corrects the target pedal additional reaction force (reaction force command value) according to the distance between the vehicles, and keeps the reaction force (additional reaction force) constant, and the spring (see FIG. 4). It does not correct the reaction force (normal reaction force) normally generated by
In other words, in the present embodiment, the total value of the additional reaction force and the normal reaction force is generated as the accelerator pedal reaction force, while the target pedal additional reaction force (reaction force command value) is corrected to correct the accelerator pedal reaction force. Only the additional reaction force forming the part is made constant. Therefore, in this embodiment, the normal reaction force by the spring 6 decreases according to the increase in the amount of return of the accelerator pedal 100, and the accelerator pedal reaction force itself includes the normal reaction force and the additional reaction force that change as such. Finally occurs in balance with.

FIG. 14 shows the relationship between the accelerator opening and the pedal effort at the measurement point where the pad position of the accelerator pedal is fixed (the reaction force action point is fixed). The pedaling force here is a value that is in balance with the accelerator pedal reaction force.
FIG. 14 shows a normal pedaling force characteristic (characteristic below the characteristic diagram) of only the normal reaction force and a pedaling force characteristic (characteristic on the characteristic diagram) when the additional reaction force is added to the normal reaction force. Show. Here, in any of the pedaling force characteristics, the pedaling force changes with respect to the accelerator opening with hysteresis. Hysteresis is, for example, due to the influence of a spring that normally generates a reaction force, for example, the influence of the engagement between the spring and its attachment site. Due to this hysteresis, the pedal force in the process of depressing the accelerator pedal may be smaller than the pedal force in the process of depressing the accelerator pedal.
Then, by correcting the final target pedal additional reaction force τ, as shown by the dotted line characteristic in FIG. 14, even if the accelerator opening is decreased, the pedaling force is not decreased accordingly. That is, even if the accelerator opening is decreased, the reaction force feeling of the driver from the accelerator pedal is not reduced.

(Modification of the embodiment)
(1) In the process of step S7, the selection pedal is selected from the target pedal additional reaction force τp of the pre-reaction force and the target pedal additional reaction force τm of the main reaction force. However, the selection method of the target pedal additional reaction force τp of the pre-reaction force and the target pedal additional reaction force τm of the main reaction force is not limited to this.
For example, when the time from when the pre-reaction force calculation condition (L2 <L) is satisfied to when the reaction force calculation condition (L1 <L) is satisfied is short (for example, 1 second), that is, in a short time There are cases where the inter-vehicle distance L interrupts the first inter-vehicle distance threshold L1. In such a case, the target pedal additional reaction force τm of the main reaction force is directly selected without going through a process of selecting the target pedal additional reaction force τp of the pre reaction force. Thereby, this reaction force can be effectively transmitted to the driver.
For example, the value of the inter-vehicle distance is shorter than the first inter-vehicle distance threshold L1 when another vehicle interrupts in front of the host vehicle or when the other inter-vehicle distance control device (ACC) switches to this control device. When interrupting by time, the target pedal additional reaction force τm of the reaction force is directly selected.

(2) In this embodiment, the accelerator pedal 100 is a lifting type accelerator pedal. On the other hand, the accelerator pedal 100 may be an organ type as shown in FIG. In this case, by depressing the accelerator pedal 100, the reaction force action point changes and the arm length becomes longer. Therefore, even in the case of the organ type accelerator pedal 100, the same effect as in the case of the lifting type accelerator pedal can be obtained.
(3) The elastic body that generates the normal reaction force shown in FIG. 4 is not limited to a spring or a spring. That is, as long as the normal reaction force can be generated, other elastic bodies can be used.

(4) The configuration of the accelerator pedal actuator 5 is not limited to the configuration shown in FIG. That is, as long as the additional reaction force can be generated, the accelerator pedal actuator 5 can have another configuration.
(5) In the present embodiment, the target pedal additional reaction force τp, τm is changed according to the elapsed time from when the inter-vehicle distance becomes smaller than the second inter-vehicle distance threshold L2 or the first inter-vehicle distance threshold L1. . On the other hand, in this embodiment, when the inter-vehicle distance is smaller than the second inter-vehicle distance threshold L2 or the first inter-vehicle distance threshold L1, the target pedal additional reaction force τp, τm is changed according to the inter-vehicle distance. You can also. Specifically, the target pedal additional reaction force τp, τm is increased as the inter-vehicle distance is shorter.

(6) In the present embodiment, as a process of applying an external force in the accelerator pedal depressing direction based on the traveling situation, when the inter-vehicle distance becomes smaller than the second inter-vehicle distance threshold L2 or the first inter-vehicle distance threshold L1, The reaction force is generated by the target pedal additional reaction force τp, τm. However, the traveling situation is not limited to such a distance between vehicles. For example, it is possible to apply an external force in the stepping-back direction of the accelerator pedal based on a traveling situation other than the inter-vehicle distance. Moreover, it can also be set as the driving | running | working condition decided paying attention to economical efficiency, such as a fuel consumption.
For example, it is possible to generate a reaction force on the accelerator pedal by notifying the driver of the change of the vehicle state such as engagement and release of the lockup clutch. As a technique for generating such a reaction force, for example, there is a technique disclosed in Japanese Patent Application Laid-Open No. 2005-132225.

  FIG. 16 is a relationship diagram showing hysteresis characteristics between the accelerator pedal stroke APS (accelerator opening) and the depression force of the accelerator pedal. FIG. 17 is a relationship diagram used for determining the threshold value APS1 of the accelerator pedal stroke APS for increasing the depression force on the accelerator pedal depression side shown in FIG. FIG. 17 shows a region of the lockup clutch disengaged state (non-L / U) in the relationship between the host vehicle speed Vsp and the accelerator pedal stroke APS (region A indicated by the hatched portion on the left side of the relationship diagram L1 in FIG. 17). It is a relationship diagram which shows the area | region of a lockup clutch fastening state (L / U).

  Here, based on the relationship diagram of FIG. 17, the controller 20 determines whether the lock-up clutch is released (non-L / U) or engaged (L / U) from the signal of the input vehicle speed Vsp and the accelerator pedal stroke APS. ). When the lockup clutch is in the engaged state (L / U), the controller 20 obtains the threshold value of the accelerator pedal stroke APS corresponding to the host vehicle speed Vsp on the relation diagram α in FIG. For example, if the host vehicle speed is Vsp1, the value APS1 of the accelerator pedal stroke APS is a threshold for increasing the pedal effort (reaction force) as shown in the figure.

Then, when the accelerator pedal stroke APS on the depression side reaches the threshold value APS1 obtained from the relationship diagram of FIG. 17, the controller 20 operates the actuator (accelerator pedal actuator 5) constituting the pedal force adding means to Increase the treading force on the stepping side. Thereby, when the value of the accelerator pedal stroke APS reaches the threshold value APS1 from the region of the lockup clutch engaged state (L / U), the pedaling force on the depression side of the accelerator pedal 2 increases. As a result, the depression force on the accelerator pedal depression side in the region of the lockup clutch released state (non-L / U) increases. Therefore, as shown in FIG. 16, the pedal force can be increased by the amount of the pedal force increase region B indicated by the oblique lines at the portion where the accelerator pedal stroke APS exceeds the threshold value APS1.
As a result, even if the driving characteristics of the vehicle, such as engagement / release of the lock-up clutch whose operating point changes with parameters other than the accelerator opening, are changed, the reaction force of the accelerator pedal can be changed to change the vehicle characteristics. The switching information can be accurately conveyed to the driver.

(7) In this embodiment, when the inter-vehicle distance between the host vehicle and the preceding vehicle becomes a predetermined inter-vehicle distance (L1 or L2), it is determined that the traveling state of the host vehicle is a high-risk state and the accelerator pedal is used. The example applied to the apparatus which gives reaction force was shown. However, the present invention is not limited to this. For example, when the vehicle speed exceeds a predetermined vehicle speed, the traveling state of the host vehicle may be determined as a high-risk state and may be applied to a device that applies a reaction force to the accelerator pedal. In addition, when the vehicle enters the curve, the curvature of the curve is detected and an appropriate vehicle speed for traveling the curve is calculated. If the vehicle speed of the vehicle is higher than the calculated vehicle speed, the traveling state of the vehicle is a risk. The present invention may be applied to a device that judges that the state is high and applies a reaction force to the accelerator pedal.

In this embodiment, the elastic body (e.g., the spring) 6 is such that the accelerator pedal is depressed when the amount of depression of the accelerator pedal operated by the driver's depression force is large than when the amount of depression of the accelerator pedal is small. A first reaction force applying means for increasing the external force applied in the return direction is realized.
Further, the accelerator pedal reaction force control device 4, the accelerator pedal actuator 5, and the target pedal additional reaction force calculation unit 23 include second reaction force applying means for applying an external force in the stepping-back direction of the accelerator pedal based on the vehicle situation. Realize.

The accelerator pedal operation amount sensor 3 realizes an accelerator pedal operation detection means for detecting the operation of the accelerator pedal.
Further, the correction processing in step S8 of the target pedal additional reaction force calculation unit 23 is performed when the accelerator pedal depression amount detected by the accelerator pedal operation detecting means is small, compared with when the accelerator pedal depression amount is large. A correction unit that corrects the external force applied by the two reaction force applying unit is realized.

Moreover, the target pedal additional reaction force calculation part 23 implement | achieves the driving | running risk detection means which detects that the driving | running state of the own vehicle is a state with a high risk as said vehicle condition.
Further, the laser radar 1 realizes an inter-vehicle distance detecting means for detecting an inter-vehicle distance between the host vehicle and the preceding vehicle as the vehicle situation.
Further, in this embodiment, when the amount of depression of the accelerator pedal operated by the driver's depression force is large, the normal reaction force transmitted from the accelerator pedal to the driver's foot is greater than when the amount of depression of the accelerator pedal is small. For a vehicle that increases the reaction force that is transmitted from the accelerator pedal to the driver's foot based on the vehicle condition, and that makes the additional reaction force added to the normal reaction force constant regardless of the depression amount of the accelerator pedal. Realize accelerator pedal reaction force application method.

(Effect of this embodiment)
(1) The first reaction force applying means applies an external force to be applied in the accelerator pedal depressing direction when the amount of depression of the accelerator pedal operated by the driver's depression force is larger than when the amount of depression of the accelerator pedal is small. Enlarge.
Further, the second reaction force applying means applies an external force in the stepping-back direction of the accelerator pedal based on the vehicle situation.
Further, the accelerator pedal operation detecting means detects the operation of the accelerator pedal.
The correcting means corrects the external force applied by the second reaction force applying means to be larger when the amount of depression of the accelerator pedal detected by the accelerator pedal operation detecting means is smaller than when the amount of depression of the accelerator pedal is large. .

As a result, the accelerator pedal reaction force imparting device for a vehicle reduces the amount of depression of the accelerator pedal and changes the way the accelerator pedal and the driver's foot are engaged. Usually, the additional reaction force transmitted from the accelerator pedal to the driver is reduced. In such a situation, the external force to be applied is corrected to be larger based on the driving situation than when the accelerator pedal is depressed a lot.
As a result, the vehicular accelerator pedal reaction force imparting device corrects to increase the external force to be applied based on the driving situation even if the manner in which the accelerator pedal and the driver's foot change during the operation of the accelerator pedal. Thus, a desired additional reaction force can be transmitted from the accelerator pedal to the driver.

(2) The traveling risk detection means detects that the traveling state of the host vehicle is in a high risk state as the vehicle situation. The second reaction force applying means applies an external force when the travel risk detecting means detects that the traveling state of the host vehicle is in a high risk state.
Thus, the driver can be accurately notified that the traveling state of the host vehicle is in a high risk state via the additional reaction force of the accelerator pedal. Furthermore, it is possible to assist the driver's deceleration operation such as switching to the brake pedal by an additional reaction force.

(3) The inter-vehicle distance detection means detects the inter-vehicle distance between the host vehicle and the preceding vehicle as a vehicle situation. The travel risk detection means detects the host vehicle when the inter-vehicle distance detected by the inter-vehicle distance detection means is less than a predetermined threshold (first inter-vehicle distance threshold L1 or second inter-vehicle distance threshold L2). It is detected that the running state of the vehicle is at a high risk state.
Accordingly, it is possible to accurately notify the driver that the inter-vehicle distance has become close via the additional reaction force of the accelerator pedal. Furthermore, it is possible to assist the driver's deceleration operation such as switching to the brake pedal by an additional reaction force.

(4) The second reaction force applying means increases the external force when the inter-vehicle distance of the vehicle is short than when the inter-vehicle distance of the vehicle is long.
In the embodiment, when the inter-vehicle distance is shortened, the pre-reaction force is switched to the main reaction force. Alternatively, the pre-reaction force itself and the main reaction force itself are increased as the inter-vehicle distance becomes shorter.
As a result, the accelerator pedal reaction force applying device for a vehicle can accurately notify the driver that the inter-vehicle distance is close via the additional reaction force of the accelerator pedal. Furthermore, the accelerator pedal reaction force applying device for a vehicle can assist a driver's deceleration operation such as switching to a brake pedal by an additional reaction force according to the inter-vehicle distance.

(5) When the amount of depression of the accelerator pedal is small, the correction means reduces the amount of change that increases the external force with respect to the change of the amount of depression of the accelerator pedal, compared to when the amount of depression of the accelerator pedal is large.
Thereby, the accelerator pedal reaction force imparting device for a vehicle can use an external force corresponding to a case where the amount of depression of the accelerator pedal is small and the additional reaction force is rapidly reduced. Thereby, the accelerator pedal reaction force applying device for a vehicle can transmit a desired additional reaction force from the accelerator pedal to the driver.

(6) The second reaction force applying means applies an external force in the stepping-back direction of the accelerator pedal according to the command value (reaction force command value). The correcting means corrects the gain of the command value coefficient (opening-dependent gain K2) to increase the external force.
Thereby, the external force can be easily corrected.
(7) The accelerator pedal reaction force imparting device for a vehicle can assist the driver to release the accelerator pedal according to the degree of approach with the front object by the pre-reaction force.

(8) The vehicular accelerator pedal reaction force applying device sets the inclination d to a value smaller than the inclination c and the reaction force D to a value smaller than the reaction force C, thereby suppressing a sense of incongruity due to the loss of the pre-reaction force. The pre-reaction force can be reduced.
(9) The vehicular accelerator pedal reaction force imparting device clarifies the difference between the pre-reaction force and the subsequent reaction force by reducing the pre-reaction force in the latter half to the reaction force c. The power can be accurately conveyed to the driver.
(10) The vehicular accelerator pedal reaction force imparting device can reduce the reaction force B in the latter half to reduce the reaction force B, thereby preventing the unnecessary reaction force from causing the driver to feel uncomfortable.

  3 accelerator pedal operation amount sensor, 4 accelerator pedal reaction force control device, 5 accelerator pedal actuator, 6 elastic body, 23 target pedal additional reaction force calculation unit

Claims (7)

A first reaction force applying means for increasing an external force applied in the stepping-back direction of the accelerator pedal when the amount of depression of the accelerator pedal operated by the driver's depression force is greater than when the amount of depression of the accelerator pedal is small; ,
A second reaction force applying means for applying an external force in a step-back direction of the accelerator pedal based on a vehicle situation;
An accelerator pedal operation detecting means for detecting an operation of the accelerator pedal;
Correction means for performing correction to increase the external force applied by the second reaction force applying means when the accelerator pedal depression amount detected by the accelerator pedal operation detecting means is smaller than when the accelerator pedal depression amount is large; ,
A vehicular accelerator pedal reaction force applying device. As the vehicle situation, comprising a running risk detection means for detecting that the running state of the host vehicle is in a high risk state,
The said 2nd reaction force provision means provides the said external force, when it is detected by the said travel risk detection means that the driving state of the own vehicle is a high risk state. Accelerator pedal reaction force imparting device for vehicles. An inter-vehicle distance detecting means for detecting an inter-vehicle distance between the host vehicle and the preceding vehicle as the vehicle situation;
The travel risk detection means detects that the travel state of the host vehicle is in a high risk state when the inter-vehicle distance detected by the inter-vehicle distance detection means is less than a predetermined threshold value. The accelerator pedal reaction force imparting device for a vehicle according to claim 2.   The said 2nd reaction force provision means makes the said external force larger when the inter-vehicle distance of the vehicle detected by the said inter-vehicle distance detection means is short than when the inter-vehicle distance of the vehicle is long. The accelerator pedal reaction force imparting device for a vehicle as described.   The correction means reduces the amount of change to increase the external force with respect to a change in the amount of depression of the accelerator pedal when the amount of depression of the accelerator pedal is small than when the amount of depression of the accelerator pedal is large. The accelerator pedal reaction force applying device for a vehicle according to any one of claims 1 to 4. The second reaction force applying means applies an external force in the stepping-back direction of the accelerator pedal according to a command value,
The accelerator pedal reaction force application for a vehicle according to any one of claims 1 to 5, wherein the correction means corrects a gain of a coefficient of the command value to increase the external force. apparatus. When the amount of depression of the accelerator pedal operated by the driver's depression force is large, the normal reaction force transmitted from the accelerator pedal to the driver's feet is increased than when the amount of depression of the accelerator pedal is small,
A reaction force transmitted from the accelerator pedal to a driver's foot based on a vehicle situation, and an additional reaction force added to the normal reaction force is made constant regardless of the depression amount of the accelerator pedal. Accelerator pedal reaction force application method.

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