Application of an artificial neural network to the control of an active external orthosis of the lower limb
The object of this paper is to present a real-time application of an artificial neural network (ANN). The application for which this network is demonstrated is a motorised orthosis with six degrees-of-freedom for use by a paraplegic; a ‘walking machine’. Theoretical networks and training methods need modification to function correctly with a real application. Several complex phenomena that are very diffucult to model have to be accommodated; the starting threshold of the activators, nonlinearity, noise, and the non-biunivocity between successive system states (position, velocity, actuator controls). The modifications made to the network and the associated training method partially alleviate these difficulties.
KeywordsActive external orthosis Feedback control Gait restoration Neural network
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