Enhanced Quadrotor Trajectory Tracking Using an Integral Sliding Mode Controller in Wind-Disturbed Environments

Unmanned Aerial vehicles (UAVs) are massively used currently for different commercial and local applications like surveillance, searching, deliverance, etc. One of the main applications of UAVs is in the field of Intelligence Transportation System (ITS). For ITS, the actual path of the trajectory should be the same as the desired input for an appropriate location with respect to the desired trajectory. Moreover, it should be fast and robust with minimal overshoot and error between desired and actual path for the desired purpose of ITS. The kinematics of the quadrotor is highly unstable and it is an underactuated system with 6 Degrees of Freedom (DOF), whereas the movement of the quadrotor is dependent upon rotational and translational subsystems. In this paper, the trajectory of the quadrotor is tracked by using the Integral Sliding Mode Controller (ISMC) which is a modified form of the Sliding Mode Controller (SMC). The advantage of using ISMC control is the robustness, convergence, accuracy and the ability to operate under varying disturbance conditions. The integral action in ISMC compensates the phenomenon of chattering which exhibits in the conventional sliding mode controller and as a result, the trajectory becomes smooth with fast converging towards the desired point. Moreover, a comparison analysis is carried out by implementing different state-of-the-art controllers including Proportional Integral Derivative (PID), Backstepping and Sliding Mode Controller (SMC) in MATLAB.