Anti-Lock Braking System Optimization for a Two-Wheeler Based on Tire-Road Friction Characteristics 2019-26-0017
Anti-lock braking system (ABS) is a well-known active safety technology widely used in cars. In principle, ABS allows an optimum braking performance by not allowing the tire to slip beyond a certain level. This guarantees steering stability and peak braking performance of the tire. The rise in the number of accidents involving powered two-wheelers (PTWs) specially in south-east Asian countries like India has led to introduction of active safety solutions in order to mitigate the number of fatalities. As the ABS controller depends on the tire characteristics information for its algorithm, a change in tire or pavement can vary the optimum operating range of ABS. In addition to this, motorcycle tires differ from a car tire in terms of its construction, dimension and compound. Therefore, the motorcycle tire’s performance envelope cannot be directly compared to a car tire. Since current ABS algorithms work on a rule-based logic, multiple trial and errors need to be conducted in order to calibrate the controller for a particular motorcycle and tire combination. This leads to an increase in the total lead time from development to actual deployment on the PTW. This work presents a methodology which aims to acquire the tire-road friction characteristics of three different tires for a study motorcycle on different friction surfaces through experimentation and estimation techniques. The optimum pressure release slip thresholds for the three tires on different surfaces are then determined from the obtained tire characteristics. Further, the ABS controller was calibrated based on the determined parameter set for the three study tires and the performance of the study motorcycle was evaluated. The chosen slip thresholds were able to utilize all the three tires sufficiently to meet the performance targets as set by IS14664.