Methods and apparatuses for backlash compensation. A dynamics inversion
compensation scheme is designed for control of nonlinear discrete-time
systems with input backlash. The techniques of this disclosure extend the
dynamic inversion technique to discrete-time systems by using a filtered
prediction, and shows how to use a neural network (NN) for inverting the
backlash nonlinearity in the feedforward path. The techniques provide a
general procedure for using NN to determine the dynamics preinverse of an
invertible discrete time dynamical system. A discrete-time tuning
algorithm is given for the NN weights so that the backlash compensation
scheme guarantees bounded tracking and backlash errors, and also bounded
parameter estimates. A rigorous proof of stability and performance is
given and a simulation example verifies performance. Unlike standard
discrete-time adaptive control techniques, no certainty equivalence (CE)
or linear-in-the-parameters (LIP) assumptions are needed.