Embedded Flexible Force Sensor for In-Situ Tire–Road Interaction Measurements

In-situ sensing the tire–road interactions such as local contact friction force distributions provides crucial information for building accurate friction force models for vehicle safety control. In this paper, we report the development of an embedded, flexible local force sensor for measuring the tire local friction forces and their distributions. A new pressuresensitive, electric conductive rubber (PSECR) sensor is used and embedded inside the tire rubber layer to extract the multidimensional local friction forces on the tire contact patch. The low-cost, flexible PSECR sensor is oriented in certain directions, and is sensitive to multiple compressive forces. To interpret the sensor measurements, we use a beam-spring model for the tire– road interactions to extract the local contact friction forces. The experimental results of stick–slip interaction testing on a motorcycle tire demonstrate the effective and good performance of the PSECR-based tire force sensor.