Design of control law and control allocation for B747-200 using a linear quadratic regulator and the active set method

This study applies the control allocation (CA) to several aircraft flight controls to produce the required body axis angular accelerations. The control law was designed using the linear quadratic regulator technique to produce the virtual control effort signals. This control law is effectively a multi-input multi-output proportional-integral controller. The virtual control efforts that are produced by the controller are then distributed by solving a multi-branch CA problem using the active set method. The solution of this CA problem is then distributed to the control surfaces. The solution is computed at a sampling frequency of 1 kHz. The designed control law and CA were then implemented in a non-linear B747-200 simulation model. The tracking performance in terms of the attitudes of the aircraft is presented.