Dynamic Tire/Road Friction Estimation With Embedded Flexible Force Sensors

Tire/road interaction estimation with embedded sensors potentially enables attractive features for enhancing vehicle safety and maneuvering stability. This article presents a new tire/road force-sensing and estimation scheme with embedded flexible force sensors. A physics-based tread beam model is developed and integrated with the LuGre friction model to evaluate the rubber deformation as well as the contact pressure distribution. A sensor model is then proposed to build the relationship between the measured longitudinal stress of tire tread rubber and the external friction force at the tire/road contact. Featuring points on measurement curves are analyzed and used to estimate tire/road friction forces. A tire friction test bed is developed for comprehensive experimental validation under various conditions, such as slip ratio, surface roughness, normal load, and velocity. Experimental results demonstrate the feasibility of using the force-sensitive sensors for predicting tire/road friction characteristics. This work shows the potential of the real-time friction-sensing technique for estimating tire/road friction forces under dynamic operating conditions.