COMPARATIVE STUDY OF DIFFERENT TYPES OF CONTROLLERS IN AN ANTI-LOCK BRAKING SYSTEM USING MATLAB/SIMULINK

Abstract

Anti-lock Braking System is one of the vital safety features in modern cars and trucks that can prevent the wheels from locking while the brakes are applied in the moving vehicles. During a braking condition, speed sensors in ABS send signals to the Anti-lock Braking System control unit to estimate the wheel slip ratio, and if the ratio is different from the desired value, the control unit will send a message to the braking actuator to control braking torque. In this paper, the dynamics and subsystems of the Anti-lock Braking System are presented and a model of the Anti-lock Braking System is developed in MATLAB/SIMULINK software. Different types of controllers, including the Bang-Bang controller, proportional-integral, proportional derivative, and proportional integral derivative controllers, are integrated into the model to investigate the effects of controlling strategies on the stopping distance, vehicle velocity, slip ratio, and braking torque. The simulation results show that the proportional derivative and proportional integral derivative controllers provide the shortest stopping distances and stopping times as compared with Bang-Bang and proportional-integral controllers on different types of roads. Furthermore, it also observed that the slip ratio during braking is kept similar to the desired value (20%) with the proportional derivative and proportional integral derivative controllers while it fluctuates between 10% and 30% for BangBang and proportional-integral controllers. The trend of the braking torque is also similar to the slip ratio. The model can be used to predict the braking performance of the Anti-lock Braking System under different conditions.