Apparatus and method for estimating maximum road friction coefficient
First Claim
1. A controller for determining a maximum friction coefficient between a tire of a wheel and a road, comprising:
- a first section that calculates a reaction force of the road to the tire of the wheel based on a tire model;
a second section that calculates a vertical load of the tire of the wheel;
a third section that calculates as a first ratio a ratio of the reaction force of the road to the vertical load;
a fourth section that calculates as a second ratio a ratio of variation in the reaction force of the road to variation in a slip ratio of the tire, the slip ratio being calculated based on the tire model; and
a fifth section that calculates a maximum road friction coefficient based on a product of a predetermined coefficient and the second ratio, and the first ratio.
1 Assignment
0 Petitions
Accused Products
Abstract
An apparatus and method that determines a maximum road friction coefficient for each wheel regardless of whether the tire is in a predetermined drive slip state, and whether the wheel is a driving wheel. The braking force of each wheel is calculated, and the longitudinal force of the tire of each wheel is calculated. Then, the driving force of the vehicle is calculated, and the lateral force of the tire of each wheel is calculated. Next, the reaction force of the road to each wheel is calculated, and the vertical load of each wheel is calculated. Finally, the ratio of variation in reaction force of the road to variation in composite slip ratio is calculated for each wheel. The sum of the ratio of the reaction force of the road to the vertical load, and the product of a predetermined coefficient and the ratio of variation in reaction force of the road to variation in composite slip ratios is calculated for each wheel as the maximum road friction coefficient.
20 Citations
19 Claims
-
1. A controller for determining a maximum friction coefficient between a tire of a wheel and a road, comprising:
-
a first section that calculates a reaction force of the road to the tire of the wheel based on a tire model;
a second section that calculates a vertical load of the tire of the wheel;
a third section that calculates as a first ratio a ratio of the reaction force of the road to the vertical load;
a fourth section that calculates as a second ratio a ratio of variation in the reaction force of the road to variation in a slip ratio of the tire, the slip ratio being calculated based on the tire model; and
a fifth section that calculates a maximum road friction coefficient based on a product of a predetermined coefficient and the second ratio, and the first ratio. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. A method for determining a maximum friction coefficient between a tire of a wheel and a road, comprising the steps of:
-
calculating a reaction force of the road to the tire of the wheel based on a tire model;
calculating a vertical load of the tire of the wheel;
calculating as a first ratio a ratio of the reaction force of the road to the vertical load;
calculating as a second ratio a ratio of variation in the reaction force of the road to variation in a slip ratio of the tire, the slip ratio being calculated based on the tire model; and
calculating a maximum road friction coefficient based on a product of a predetermined coefficient and the second ratio, and the first ratio. - View Dependent Claims (11, 12, 13, 14, 15, 16, 17, 18)
-
-
19. An controller for determining a maximum friction coefficient between a tire of a wheel and a road, comprising:
-
a first section that calculates a reaction force of the road to the tire;
a second section that calculates a vertical load of the tire;
a third section that calculates variation in a slip ratio of the tire;
a fourth section that calculates variation in the reaction force of the road to the tire; and
a fifth section that calculates a maximum road friction coefficient based on the reaction force of the road, the vertical load, the variation in the slip ratio, and the variation in the reaction force of the road.
-
Specification