Online neural identification of multi-input multi-output systems

A feedforward neural network tuning algorithm is developed, which is suitable for identification of multi-input multi-output nonlinear functions, by utilising the learning method of a conventional neuro-adaptive control technique. Using Lyapunov functions, it is shown that not only the approximation error converges to values that have arbitrarily reducible upper bounds, but also the weights of the neural network remain bounded. The effectiveness of the identification method and its application in force-control of an uncertain robot interacting with an unknown flexible environment are investigated as an application example.