Design and implementation of decoupled compensation for a twin rotor multiple-input and multiple-output system

This study achieves compensation of a physical twin rotor multiple-input and multiple-output system in two steps: (i) input-output decoupling its transfer function model, obtained by linearising its non-linear model around an operating point, using an open-loop, minimal precompensator and (ii) effecting 2-degree of freedom single-input and single-output (SISO) compensations for the resulting SISO-decoupled units. While step (i) ensures decoupling in the responses, the other performances (such as robustness, tracking, disturbance rejection, etc.) can be achieved using SISO compensations in step (ii) above. The performances of the compensated system in respect of decoupling, loop robustness and disturbance rejection are verified through simulations and experiments. The results are also compared with the existing ones.