To improve comfortableness of riding on a vehicle by optimizing control parameters by genetic algorithm by using as an evaluation function the difference in time differentiation between the entropy in a shock absorber and entropy given to the shock absorber from a controller.

An optimization part provided to a learning part of a control system optimize the control parameters by making the tutor signal (input/output value of fuzzy neural network) of a controller for learning genetically evolve by using as the evaluation function the difference between the time differential dSc/dt of the entropy from the controller for learning and the time differential dSs/dt of the internal entropy of a vehicle and a suspension to be controlled which is obtained from a motion model and by using a genetical algorism so as to reduce the time differential difference. Consequently, the turning performance of the vehicle and comfortableness of riding the vehicle can be improved.