Model Based Control of Heavy Road Vehicle Brakes for Active Safety Applications

With increasing numbers of road vehicles and accident fatalities, it is imperative to equip vehicles with active safety systems that can assist drivers. The commonly used actuator in any such active safety system is the vehicle brake system and hence its accurate control becomes important. This paper presents a systematic procedure for modeling the pneumatic brake system in heavy road vehicles using a Linear Time Invariant (LTI) approximation and controlling it based on the developed model. The proposed modeling approach is based on frequency response in the system's frequency range of interest and time response of the system. The model thus obtained was then used to systematically design controllers for brake pressure regulation. The good correlation of theoretical and experimental results corroborated the overall procedure followed for modeling and controller design. Such a controller would serve as an inner loop controller in vehicle control systems like wheel slip regulation, thus improving the brake system performance and vehicle stability.