Open AccessIntegrated fault‐tolerant control for a 3‐DOF helicopter with actuator faults and saturation
Author(s) -
Lan Jianglin,
Patton Ron J.,
Zhu Xiaoyuan
Publication year - 2017
Publication title -
iet control theory and applications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.059
H-Index - 108
eISSN - 1751-8652
pISSN - 1751-8644
DOI - 10.1049/iet-cta.2016.1602
Subject(s) - control theory (sociology) , actuator , robustness (evolution) , fault tolerance , control engineering , engineering , plant , computer science , control (management) , biochemistry , chemistry , electrical engineering , gene , artificial intelligence , reliability engineering
This study proposes a fault estimation (FE)‐based fault‐tolerant control (FTC) strategy to maintain system reliability and achieve desirable control performance for a 3‐DOF helicopter system with both actuator drift and oscillation faults and saturation. The effects of the faults and saturation are combined into a composite non‐differentiable actuator fault function, which is approximated by a differentiable function and estimated together with the system state using a non‐linear unknown input observer. An adaptive sliding mode controller based on the estimates is developed to compensate the effects of the faults and saturation. Taking into account the bi‐directional robustness interactions between the FE and FTC functions, an integrated design approach is proposed to obtain the observer and controller gains in a single step, so as to achieve robust overall FTC system performance. In fault‐free cases, the proposed strategy can be considered as a new approach for anti‐windup control to compensate the effect of input saturation. Comparative simulations are provided to verify the effectiveness of the proposed design under different actuator fault scenarios.