Double loop controller design for the vehicle´s heading control

In this study, an electrically powered vehicle has been implemented to perform an unmanned ground vehicle purpose. The steering system is modified to automatically control by installing the DC servo motor at the steering wheel shaft. The compass sensor used as the feedback sensor to measure the current heading angle of the vehicle. The autonomous navigation system determines the general sense of direction of travel and sends that information to the vehicle´s control system. The objective of this research is to control the heading of a vehicle in the real world environment under the unpredictable and unstructured surrounding. The change of heading direction and the speed of the vehicle influences to the motion of a vehicle. In this work, the double loop controller is designed. The inner loop performs the steering system control and the outer loop archives vehicle´s heading control. In the simulation, 2 different conditions are simulated. First, a vehicle is controlled by using the single loop PID controller at the different levels of vehicle´s ground speed and also different levels of heading angle input. Second, a vehicle is simulated at the same conditions but replacing the single loop controller with the double loops PD-PID controller. For the experiment, the PD-PID controller is applied to control the heading of a vehicle in tested field with 2 levels of speed.