Modeling, simulation and control study for the quad-copter UAV

In the recent years UAV (Unmanned Aerial Vehicles) having quad-copter helicopter i.e. quad-copter configuration have been receiving increasing attention amongst the global researchers due to its wide-range of applications such as surveillance in military, civilian and disaster management applications. This paper presents our investigations on the modeling, simulation, altitude model validation and comparison of some popular quad-copter control schemes. Quad-copter consists of two pairs of counter rotating rotors situated at the ends of a cross frame, symmetric about the centre of gravity, which coincides with the origin of the reference systems used. The model used in our work is based on the Euler Lagrange method used to derive the defining equations of motions of the six degree of freedom system with minor changes to consider variable air-density. This modified model is then simulated in matlab-simulink framework to dynamically compute the quad-copter altitude and attitude. Also, some commonly used control algorithms like PD, PID and back-stepping control are compared using our modified model simulation framework computing certain well-known performance metrics, like ISE, IAE, for the closed loop altitude and attitude control.