Reaction force imparting system and reaction force imparting method of vehicle accelerator pedal

1. A reaction force imparting system of a vehicle accelerator pedal, comprising:

a running circumstance detection apparatus configured to detect two or more running circumstances of a vehicle;

a reaction force generation apparatus configured to, depending on the running circumstance detected by the running circumstance detection apparatus, generate reaction force for an accelerator pedal in a returning direction thereof based on a predetermined reaction force target value, wherein the accelerator pedal is operated by tread force of a driver, and the predetermined reaction force target value is differentiated according to each of the running circumstances; and

a reaction force correction apparatus configured to make correction to reduce the reaction force currently generated by the reaction force generation apparatus when it is predicted that the predetermined reaction force target value is increased by a change of a running circumstance detected by the running circumstance detection apparatus, and a difference between the predetermined reaction force target value corresponding to the running circumstance after the change and the reaction force currently generated by the reaction force generation apparatus is less than a predetermined difference.

2. The reaction force imparting system according to claim 1 , wherein the reaction force correction apparatus is configured to make the correction to reduce the reaction force currently generated by the reaction force generation apparatus so that the difference between the predetermined reaction force target value corresponding to the running circumstance after the change and the reaction force currently generated by the reaction force generation apparatus can become equal to or more than the predetermined difference.

3. The reaction force imparting system according to claim 1 , wherein the reaction force correction apparatus is configured to make the correction to reduce the reaction force currently generated by the reaction force generation apparatus if priority to generate the reaction force in response to the running circumstance after the change is higher than priority to generate the reaction force in response to a current running circumstance.

4. The reaction force imparting system according to claim 3 , wherein the priority is higher when a risk degree in the running circumstances is high than when the risk degree is low.

5. The reaction force imparting system according to claim 1 , wherein the predetermined difference is set correspondingly to the predetermined reaction force target value corresponding to the running circumstance after the change.

6. The reaction force imparting system according to claim 1 , wherein the predetermined difference is set based on an accelerator pedal opening.

7. The reaction force imparting system according to claim 1 , wherein one running circumstance among the two or more running circumstances is a circumstance in which an approaching degree between the vehicle and an object on a periphery of the vehicle has reached a predetermined approaching degree, and the other running circumstance is not based on the approaching degree between the vehicle and the object, and

the reaction force correction apparatus is configured to predict that the predetermined reaction force target value is increased when it is predicted that, depending on the approaching degree between the vehicle and the object, the running circumstance detected by the running circumstance detection apparatus is changed from the other running circumstance to the one running circumstance.

8. The reaction force imparting system according to claim 1 , wherein the reaction force correction apparatus is configured to make the correction to reduce the reaction force at a predetermined reduction rate.

9. The reaction force imparting system according to claim 1 , wherein the predetermined reaction force target value corresponding to each of the running circumstances is set based on a road gradient.

10. The reaction force imparting system according to claim 1 , wherein the predetermined reaction force target value corresponding to each of the running circumstances is set based on an accelerator pedal opening.

11. A reaction force imparting method of a vehicle accelerator pedal, comprising:

depending on two or more running circumstances of a vehicle, generating reaction force for an accelerator pedal in a returning direction thereof based on a predetermined reaction force target value, wherein the accelerator pedal is operated by tread force of a driver, and the predetermined reaction force target value is differentiated according to each of the running circumstances; and

making correction to reduce the currently generated reaction force when it is predicted that the predetermined reaction force target value is increased by a change of a running circumstance, and a difference between the predetermined reaction force target value corresponding to the running circumstance after the change and the currently generated reaction force is less than a predetermined difference.

12. A reaction force imparting system of a vehicle accelerator pedal, comprising:

running circumstance detection means for detecting two or more running circumstances of a vehicle;

reaction force generation means that, depending on a running circumstance detected by the running circumstance detection means, generates reaction force for an accelerator pedal in a returning direction thereof based on a predetermined reaction force target value, wherein the accelerator pedal is operated by tread force of a driver, and the predetermined reaction force target value is differentiated according to each of the running circumstances; and

reaction force correction means for making correction to reduce the reaction force currently generated by the reaction force generation means when it is predicted that the predetermined reaction force target value is increased by a change of the running circumstance detected by the running circumstance detection means, and a difference between the predetermined reaction force target value corresponding to the running circumstance after the change and the reaction force currently generated by the reaction force generation means is less than a predetermined difference.

13. A reaction force imparting system of a vehicle accelerator pedal, comprising:

a running circumstance detection apparatus configured to detect running circumstances of a vehicle, the running circumstances comprising: an approaching degree between the vehicle and an object on a periphery of the vehicle; and a circumstance where an accelerator pedal stroke exceeds a predetermined threshold;

a reaction force generation apparatus configured to, depending on a running circumstance detected by the running circumstance detection apparatus, generate reaction force for an accelerator pedal in a returning direction thereof based on a predetermined reaction force target value, wherein the accelerator pedal is operated by tread force of a driver, and the predetermined reaction force target value is differentiated according to each of the running circumstances; and

a reaction force correction apparatus that is configured to make correction to reduce the reaction force currently generated by the reaction force generation apparatus when it is predicted that the predetermined reaction force target value is increased by a change of the running circumstance detected by the running circumstance detection apparatus, and a difference between the predetermined reaction force target value corresponding to the running circumstance after the change and the reaction force currently generated by the reaction force generation apparatus is less than a predetermined difference.