New Electonically Controlled Torque Split 4WD System for Improving Cornering Performance

A new 4WD systen called the “ATTESA E-TS” has been developed based on a new approach to traction control. The E-TS system employs electronic control to achieve an optimm torque split ratio between the front and rear axles. This system is designed not only to deliver high tractive performance, but also to improve cornering performance under various road-surface friction coefficients and engine outputs. It consists of a transfer unit containing a multiplate clutch, a hydraulic unit, and a control system which is integrated with an anti-lock brake system and employs a wheel speed sensor at each wheel as well as a lateral acceleration sensor.