4 wheel Drive, control manner null of Drive power distributing and rear wheel steering angle 4 wheel steering

摘要

PURPOSE:To gain the merits of both the torque split control and the rear wheel steering control by comparing the actual lateral acceleration rate and a computed virtual lateral acceleration rate during the front wheel steeling time, compensating and controlling the distribution of driving forces to the front and rear wheels and the steering angle of rear wheels when a difference between both the above acceleration rates is over or under the specified value. CONSTITUTION:A controller 29 computes a virtural lateral acceleration rate using the data of front wheel steering angle and a car speed at the steering time and compares said virtual rate with an actual lateral acceleration rage detected by a lateral G sensor 28. When a difference between both said acceleration rates is higher than the set value epsilon, the vehicle is evaluated to be in a tendency to the spinning state so that the distribution rate to front wheel driving forces and the steering angle of the same phase direction for the rear wheels are corrected to become high. According to the total driving force, the distribution rate to the front wheel driving force and the steering angle of the same phase direction for the rear wheels are controlled correctly. When a difference between both the acceleration speeds is lower than the set value -epsilon, the vehicle state is evaluated as the drift state, on account of which the distribution rate to the rear wheel driving force and the steering angle of the same phase direction for the rear wheels are corrected to higher and lower, respectively. According to the total driving force, the distribution rate of driving force for the rear wheels and the steering angle of the same phase direction for the rear wheels are controlled correctly.