Experimental Study on Road Friction Variation and Stopping Distance Uncertainty using ABS Braking Data

Preprint, 2022

This paper investigates the remaining fluctuation of road friction and stopping distance when the contribution from known sources has been removed. This fluctuation can serve as uncertainty for active safety functions relying on friction estimates. Data from repeated ABS brake maneuvers on several uniform road conditions, including high and low friction surfaces, is analyzed. Road friction estimates are obtained and used to estimate the uncertainty in road friction and stopping distance. Measurements from the same road segment show a friction uncertainty of less than 0.1 with the presented procedure. The stopping distance uncertainty becomes considerable at high speeds and low friction for the intended use in emergency brake functions. Especially for low friction, high estimate accuracy is motivated.