Real Time Experiments on the Twin Rotor MIMO System and its Robust Control: Flying TRMS

It has been a passion for me to design controllers for real time plants, the aerospace vehicles or their prototypes, to be specific, since my graduate days (Master's degree in India). As a serendipity, I encountered the Twin Rotor MIMO System (acclaimed worldwide for its RHP dynamics and laboratory experiments), TRMS in short, by M/s Feedback Instruments ltd. However, I could not solve the two by two controller design problem during my Master's program. Naturally, I retreated to the same institute, the same department, and the same lab to complete my pending mission during my PhD work. After enduring technical and administrative calamities for several years, I could solve the problem to thank my faith, perseverance and support by the stake holders, eventually.
I applied my understanding of TRMS in terms of its RHP zero dynamics, cross coupling, model uncertainties, exogenous inputs, singularities, and resonances in controller design. Further, TRMS has low pass filtering characteristic. This book contains a series of experiments on TRMS that lead to designing an H∞ controller based on the nominal Linear Time Invariant (LTI) model of the system.
The initial experiments resulted in extracting a nominal LTI models of TRMS. An H∞ controller was designed due to the proper and stable transfer functions derived. The system was tested in real time with the proposed controller for disturbance rejection at the output and commendable results.
Even if the book has covered step by step designing of an H∞ controller, yet the essence of the compilation lies in the real time experimentation of TRMS in an indoor environment that is covered comprehensively.