A method of optimal wheel torque determination for independent wheel drive vehicles

A method of optimal wheel torque determination for electric motor vehicles is presented. Electric motor vehicles are increasing with the rise of public interest in environmental protection. In the case of vehicles driven by controllable motors on each individual wheel, the determination of the wheel torque is an essential factor for efficient driving. In this research, a method of optimal torque determination has been formulated by using the variational principle to minimize frictional work done by the tires with the ground contact. Optimal torque on each wheel for a four-wheel vehicle was numerically obtained by solving the equations under several driving conditions. The result of the numerical simulation is useful as a guide to control the motor torque of electric vehicles for efficient driving.