A robust adaptive control of a parallel robot

• Published in: International journal of control Vol. 83; no. 10; pp. 2107 - 2119
• Main Authors: Achili, B., Daachi, B., Amirat, Y., Ali-cherif, A.
• Format: Journal Article
• Language: English
• Published: Abingdon Taylor & Francis Group 01-10-2010; Taylor & Francis; Taylor & Francis Ltd
• Subjects: Adaptative systems; Applied sciences; Computer Science; Computer science; control theory; systems; Control system analysis; Control theory. Systems; Exact sciences and technology; Modelling and identification; neural network; Neural networks; parallel robot; Robotics; Robots; robust control; sliding modes; stability analysis; Studies; Gravitational force; Variable structure control; Sliding mode; Parallel mechanism; Taylor series; Tracking task; Neural network; Adaptive control; Inverse problem; Closed feedback; Robust control; Reference model; Friction; Linkage mechanism; Distributed control; Series expansion; Multilayer perceptrons; System identification; Dynamic model; Lyapunov function; Multilayer network
• ISSN: 0020-7179; 1366-5820
• DOI: 10.1080/00207179.2010.505965

The work presented in this article deals with the robust adaptive control tracking of a 6 degree of freedom parallel robot, called C5 parallel robot. The proposed approach is based on the coupling of sliding modes and multi-layers perceptron neural networks (MLP-NNs). It does not require the inverse dynamic model for deriving the control law. The MLP-NN is added in the control scheme to estimate the gravitational and frictional forces along with the non-modelled dynamic effects. The nonlinearity problem, present in neural networks, is resolved using Taylor series expansion. The proposed approach allows to adjust the parameters of neural network and sliding mode control terms by taking into account a reference model and the closed-loop stability in the Lyapunov sense. We implemented our approach on the C5 parallel robot of LISSI laboratory and performed experiments to observe its effectiveness and the robust behaviour of the controller against external disturbances.