Use of an extended Kalman filter as a robust tyre force estimator

Abstract

Control systems designed to optimize vehicle performance, such as antilock braking systems or traction control systems, depend upon a knowledge of the amount of available grip at the tyre–road contact point. There have been both qualitative and quantitative approaches to identify the road surface coefficient of friction, μ. This work proposes a method of estimating the longitudinal and lateral grips for use within a control system. The estimation method is explained and the vehicle model equations used are stated. The estimator is then tested using logged data from a test vehicle, and the force estimates are validated against results from strain-gauged wheel rims. Finally, the direction of future work is described.

Keywords:

• Extended Kalman filter
• Tyres
• State estimation