Nonlinear robust decoupling control design for twin rotor system

A new sliding surface has been proposed to handle cross-coupling affects in a twin rotor system. This cross-coupling leads to degraded performance during precise maneuvering and it can be suppressed implicitly either by declaring it as disturbance or explicitly by introducing decoupling techniques. Sliding mode control offers robustness against cross-coupling as well as performance along with the freedom to operate the system in nonlinear range. However, the standard linear H_infin controller synthesized by loop-shaping design procedure (LSDP) offers robustness at the cost of performance to overcome cross-coupling. The synthesized sliding mode controller has been successfully tested in simulations and verified through implementation on a twin rotor system.