Constrained Multi-objective Optimisation of a Controller for a Highly Nonlinear Aeroelastic Structure—methodology

The need for weight-optimised aerospace structures results in flexible structures with highly nonlinear behaviour. Their control presents challenges that require control theory be developed in order to enable the trend toward lighter structures to continue. Two classes of problem of particular interest in control are systems with a high degree of nonlinearity inherent in the structure and those with nonlinear and noncontinuous external forces. These are represented respectively by space structures and those subject to aeroelastic effects. The problem of control of highly flexible space structures have previously been considered by the author (Zadeh, Scott and Wood, 1997; Drack, Zadeh, Wharington, Herszberg and Wood, 1999; Zadeh, 2002). Optimal control of a two dimensional aeroelastic (wing) structure with three degrees of freedom is considered. Because of publication space limitations, modelling of the testbed and design of the nominal controller are submitted as a separate, lead-on, publication (Zadeh, 2005).