Active versus passive fault tolerant control of a High Redundancy Actuator

• Published in: ECC : 2009 European Control Conference : 23-26 August 2009 pp. 3671 - 3676
• Main Authors: Davies, Jessica, Steffen, Thomas, Dixon, Roger, Goodall, Roger, Zolotas, Argyrios
• Format: Conference Proceeding Journal Article
• Language: English
• Published: IEEE 01.08.2009
• Subjects: Active control; active fault tolerance; Actuators; Circuit faults; control reconfiguration; Control systems; Expert systems; fault accommodation; Fault tolerance; Fault tolerant systems; fault-tolerant control; Faults; high redundancy actuator; multi-agent systems; passive fault tolerance; Redundancy; Robust control; Robustness; Tradeoffs
• ISBN: 9783952417393; 3952417394
• DOI: 10.23919/ECC.2009.7074970

The High Redundancy Actuator (HRA project investigates the use of large numbers of small actuation elements to achieve fault tolerance. The large number of components involved poses a unique challenge from a control perspective. This paper presents the two main options to control the HRA: using robust control (passive fault tolerance), and reconfigurable control (active fault tolerance). The robust controller is designed using H ∞ methods, and handles the different system behaviours of the HRA with only small changes to the closed-loop system. In contrast, control reconfiguration detects the fault and changes the control laws accordingly. Multi-Agent System (MAS) concepts are used to apply localised multiple-model control and fault detection on an individual element level. The results of both approaches are compared to illustrate the trade-off between the complexity of the control approach and the resulting performance under different fault situations.