Control systems for a helicopter with two degrees of freedom

The goal of this article is to model and control a helicopter of two degrees of freedom, better known as a twin rotor Multiple Inputs Multiple Outputs (“MIMO”) system, those mobility points of freedom allows the helicopter to be positioned in Pitch and Yaw angles. This system has exceptional characteristics that make it a challenge to be controlled; given the fact that it is a non-linear, multi-variable and an unstable system. In order to acquire a control system with high performance and robustness, the helicopter must be held with various strategies and their results need to be compared to identify the best one. The control schemas used are Single Input Single Output (“SISO”) PID control, Uncoupled MIMO Cross-Control and a Servotracking control with a state observer.