A Viable Multivariable Adaptive Controller With Application To Autonomous Helicopters

Download or read book A Viable Multivariable Adaptive Controller with Application to Autonomous Helicopters written by Ashish Samuel Krupadanam and published by . This book was released on 2001 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt: (Cont.) parameters. Closed-loop stability and robustness are demonstrated through the use of suitable Lyapunov functions. Judicious integration between linear robust control methods and online adaptive strategies is incorporated in the control design to maximize off-line information about the nominal conditions and on-line measurements. A two-step nonlinear optimization procedure is carried out to determine nominal trim states that allows the arbitrarily close convergence to the global minima by making use of prior information available about sub-components of the trim states during a given maneuver. The control design methodology is tested on a high fidelity simulation of a Draper Laboratory autonomous helicopter. Extensive simulation studies were carried out, beginning from a vehicle model that includes complete vehicle aerodynamics, gravitational and inertial effects, rotor dynamics, and rotor-vehicle interactions. Five different inputs including the roll-cyclic and pitch cyclic angles of the main rotor, the pedal command for the tail rotor, collective pitch angle for the main rotor, and the throttle are assumed to be present. The controller is evaluated at various operating conditions and maneuvers where aerodynamic nonlinearities and parametric uncertainties become dominant. Simulations are performed on a nonlinear longitudinal dynamics model to track step and sinusoidal changes in forward flight velocity, and a maneuver involving jumps over hurdles. Simulations on the full three dimensional nonlinear helicopter model are performed for vertical flight and coordinated turn maneuvers ...