Accommodation of actuator faults using control allocation with modified daisy chaining

This paper presents a fault-tolerant control technique based on control allocation with a modified daisy chaining method that utilizes the benefit of smart actuators. For tolerating actuator faults, control allocation has been widely adopted together with a daisy chaining method to generate virtual control inputs for the actuators that are partitioned into several groups. However, the existing daisy chaining method cannot compensate the effect of faulty actuators which belong to the last group. In this work, a modified daisy chaining method is proposed in order to overcome the problem. By utilizing the ability of self-diagnosis of a smart actuator, the proposed method reorders the actuator groups so that actuators having the less significant fault are placed in the upper groups. The effectiveness of the proposed method is demonstrated through a set of computer simulations with an airplane.