Estimation of momentary wheel force coefficients by using a fusion of drive dynamic sensors and GPS data

Abstract

This paper presents a method to determine the momentary lateral and longitudinal force coefficients by calculating lateral, longitudinal, and vertical forces at the wheels. The longitudinal forces of the wheels are calculated for known accelerationand braking torques. A rigid body model is used to determine the vertical wheel forces. The determination of lateral forces is based on a single-track model. A kinematic Kalman filter, which is independent from any unknown vehicle parameters, is used to estimate the sideslip angle. Using a 3-antenna GPS-receiver the estimation problem can be decoupled into two Kalman filters. The integration of vehicle dynamic sensors and a 3-antenna GPS-receiver enables a high sampling rate and improved accuracy. Based on the state estimation the unknown physical parameters of the wheel force models (such as position of center of gravity, moment of inertia, …) are determined using approximations and least squares parameter estimation.