Patent ID: 8326487

Claim:
A method for estimating a normal force at a wheel of a vehicle, the vehicle comprising a plurality of suspension displacement sensors with each of the plurality of suspension displacement sensors positioned proximal to a suspension element of the vehicle, the method comprising: obtaining a suspension displacement value from at least one of the plurality of suspension displacement sensors; estimating a spring force based on the suspension displacement value, wherein the spring force is the force acting on a spring of the suspension element; estimating a damper force based on the suspension displacement value, wherein the damper force is the force acting on a damper of the suspension element; estimating a force at the center of the wheel based on an acceleration of a center of the wheel and an unsprung mass of the vehicle, where the acceleration of the center of the wheel is a second order derivative of the suspension displacement value with respect to time; and determining the normal force at the wheel of the vehicle based on the spring force, the damper force and the force at the center of the wheel of the vehicle.