Vehicle controller

1. A vehicle controller comprising:

a lateral slip amount calculating section which calculates a lateral slip amount indicating a degree to which a target wheel to be controlled which is a front wheel or a rear wheel of a vehicle is slipping in a rightward and leftward direction on a ground surface;

a lateral slip suppressing control section which performs a lateral slip suppressing control including at least one of a control for reducing an absolute value of a command value of a longitudinal force in a forward and rearward direction which is applied from the ground surface to the target wheel and a control for increasing a distributed load applied to the target wheel, in a case where the lateral slip suppressing control section determines that the lateral slip amount is greater than a lateral slip limit threshold;

a normal force estimating section which estimates a normal force based on a ratio of a load of the front wheel to a load of the rear wheel; and

a threshold deciding section which decides the lateral slip limit threshold based on the normal force applied to the target wheel.

2. The vehicle controller according to claim 1 ,

wherein the threshold deciding section decides the lateral slip limit threshold based on the longitudinal force in addition to the normal force.

3. The vehicle controller according to claim 1 ,

wherein the normal force estimating section estimates the normal force based on a ratio of an extension amount of a front suspension to an extension amount of a rear suspension.

4. The vehicle controller according to claim 1 ,

wherein the lateral slip suppressing control section performs the lateral slip suppressing control, in a case where the lateral slip suppressing control section determines that the vehicle is accelerated or decelerated.

5. The vehicle controller according to claim 1 ,

wherein the lateral slip suppressing control section performs the lateral slip suppressing control, in a case where the lateral slip suppressing control section determines that a rider is performing an operation for accelerating the vehicle or performing a braking operation.

6. The vehicle controller according to claim 1 ,

wherein the lateral slip suppressing control section controls at least one of a plurality of suspensions which are provided at the front wheel and the rear wheel, respectively, to increase the distributed load applied to the target wheel, in a case where the lateral slip suppressing control section determines that the lateral slip amount is greater than the lateral slip limit threshold.

7. The vehicle controller according to claim 1 ,

wherein the lateral slip suppressing control section controls at least one of driving power or a braking force of the target wheel and an operation resistance of a driving power source which generates the driving power for allowing the vehicle to travel, in a case where the lateral slip suppressing control section determines that the lateral slip amount is greater than the lateral slip limit threshold.

8. The vehicle controller according to claim 1 , further comprising:

a lateral slip prevention control section which performs a lateral slip prevention control for controlling the command value of the longitudinal force so that a total force of a lateral force and the longitudinal force which are applied to the target wheel does not exceed a gripping limit of the target wheel with respect to the ground surface, before the lateral slip amount exceeds the lateral slip limit threshold.

9. The vehicle controller according to claim 1 , further comprising:

a longitudinal slip amount calculating section which calculates a longitudinal slip amount indicating a degree to which the target wheel is slipping in a forward and rearward direction on the ground surface; and

a longitudinal slip suppressing control section which reduces an absolute value of the longitudinal force, in a case where the longitudinal slip suppressing control section determines that the longitudinal slip amount is greater than a longitudinal slip threshold.

10. A vehicle controller comprising:

a lateral slip amount calculating section which calculates a lateral slip amount indicating a degree to which a target wheel to be controlled which is a front wheel or a rear wheel of a vehicle is slipping in a rightward and leftward direction on a ground surface;

a lateral slip suppressing control section which performs a lateral slip suppressing control including at least one of a control for reducing an absolute value of a command value of a longitudinal force in a forward and rearward direction which is applied from the ground surface to the target wheel and a control for increasing a distributed load applied to the target wheel, in a case where the lateral slip suppressing control section determines that the lateral slip amount is greater than a lateral slip limit threshold; and

a threshold deciding section which decides the lateral slip limit threshold based on at least one of the longitudinal force and a normal force applied to the target wheel,

wherein the lateral slip suppressing control section controls at least one of a plurality of suspensions which are provided at the front wheel and the rear wheel, respectively, to increase the distributed load applied to the target wheel, in the case where the lateral slip suppressing control section determines that the lateral slip amount is greater than the lateral slip limit threshold.