Full-Order Multiple Observer with Applications to Airplane Landing

The paper deals with the design of a new full-order multiple observer for Takagi-Sugeno fuzzy systems. It can achieve the finite-time state and unknown input reconstruction for multiple models with unknown inputs; the obtaining of the full-order multiple observer is achieved by combining a classical full-order observer for linear time-invariant multivariable systems with unknown inputs and a full-order multiple observer for Takagi-Sugeno fuzzy systems. The advantages of the multiple observer are the lack of existence conditions, due to a “while” loop included in the associated design algorithm, and the avoidance of the pole placement technique. To ensure the cancel of the states' estimation errors and to study the stability of the multiple observer, a Lyapunov function has been considered. The steps of the design procedure have been software implemented and validated for a very difficult phase of airplanes' flight - the landing.