Tire grip level estimation apparatus and method, and running condition control method

摘要

An SAT estimator 16 estimates the SAT generated between the road surface and the tire. A slip angle arithmetic unit 18 estimates the front wheel slip angle. A lateral force detector 180 computes the lateral force generated in the wheels. An SAT model value arithmetic unit 22 computes the SAT model value from the slip angle estimate and the lateral force value. A front-rear direction quantity-of-state arithmetic unit 240 computes the front-rear direction quantity of state generated in the wheels. A grip level estimator 26 estimates the grip level from the SAT estimated by the SAT estimator 16, the SAT model value computed by the SAT model value arithmetic unit 22, and the front-rear direction quantity of state estimated by the front-rear direction quantity-of-state arithmetic unit 240.