Author: Kevin A. Sheehan

Publisher:

Published: 1985

Total Pages: 378

ISBN-13:

Proportional plus integral controllers are designed for the longitudinal mode using a multivariable control law theory developed by Professor Brian Porter of the University of Salford England. Control laws are formulated by use of a computer-aided multivariable design program entitled MULTI. In addition MULTI performs a digital closed-loop simulation for controller performance analysis. The aircraft model is developed from linearized data provided by McDonnell Aircraft Co. the prime contractor for the F-15/STOL. Canard and thrust vectoring technology, in addition to conventional control surfaces, are included in the model. Decoupling of the longitudinal output variables is achieved and demonstrated by four maneuvers (pitch-pointing, vertical translation, direct climb, and constant g pull-up). Plant parameter variation effects are also examined. Destabilizing effects to include actuator and sensor dynamics computational time delay random Gaussian sensor noise and simulation nonlinearities are included. Results show stable responses for all simulations. Except for the most demanding simulations (all destabilizing effects considered), controller responses are smooth and well behaved. Recommendations include proposed future work in thrust vector modeling and suggested improvements to the computer-aided design program, MULTI.