Researchers from German Aerospace Center designed and validated a fault tolerant gust load alleviation control system on a flexible wing in a wind tunnel
The focus on sustainable use of energy and more economic operation of aircraft has increased in the recent past. Manufacturers and researchers are focused on developing efficient engines and aerodynamics that enhance aircraft performance and reduce fuel costs. One such development includes alleviation of wing gust loads, which helps to reduce weight of the aircraft. Now, a team of researchers from the Institute of System Dynamics and Control, German Aerospace Center developed a fault tolerant gust load alleviation system.
The novel control system contains three major parts: a baseline controller, a fault detection system, and a reconfigurable control allocation. The baseline controller aids in reducing the loads in the wing. The fault detection system is used to monitor the actuator condition. The reconfigurable control allocation enables to reduce the fault effect when detected. The control inputs and measurement outputs are blended to add damping to the aeroelastic system, which further helps to mitigate structural loads. The fault tolerant control approach is based on two main modules: a fault detection system and a reconfigurable control allocation. The fault detection system consists of a linear fault detection filter of minimal state order that generates a residual signal to detect the fault.
The information of the fault detection system triggers the reconfigurable control allocation to recover the ideal control performance during the fault scenarios. The linear residual filter design is based on advanced nullspace computation techniques that offer the least possible filter order by offering residual filters of minimal dependence on the underlying model. This in turn helps to determine if the fault detection problem is solvable. The team relied on wind tunnel based control system validation to verify the control system for a manufactured flexible wing. The research was published in the journal MDPI Aerospace on June 30, 2019.