Compensation of jammed control surface of large transport aircraft by control reconfiguration

This paper addresses the control allocation to several aircraft flight controls to produce required body axis angular accelerations. Two methods of control law design are used to produce the virtual control effort signals, which are then distributed by solving sequential least squares problem using active set method to the flight control surfaces to generate this effort. Two cases are described: in the first case the control law and allocation for the healthy aircraft is implemented, and in the second case, jamming of one control surface is introduced at time zero. In this case it was shown that how controller and allocation compensate for this failure without changing the control law. To implement this system it was assumed that there is a good fault identification system onboard. Normally aircraft are over-actuated and in the case of a control failure this over actuation is more pronounced due to coupling of aircraft dynamics. The problem of control allocation presented here is a convex problem so there is always a unique solution.