Robust decoupling control design for twin rotor system using Hadamard weights

This paper considers cross-coupling affects in a twin rotor system that leads to degraded performance during precise helicopter maneuvering. This cross-coupling can be suppressed implicitly either by declaring it as disturbance or explicitly by introducing decoupling techniques. The standard H∞ controller synthesized by loop-shaping design procedure (LSDP) offers robustness at the cost of performance to overcome cross-coupling. However, Hadamard weights are used to decouple the system dynamics to give desired performance as well. This idea has been successfully proved by simulations and verified through implementing it on a twin rotor system.