Global TCF based contouring controller design for an industrial biaxial precision gantry with accurate parameter estimations

This paper presents a global task coordinate frame (TCF) based integrated direct/indirect adaptive robust contouring controller (DIARC) for an industrial biaxial gantry that achieves not only excellent contouring performance but also accurate parameter estimations. Contouring control problem is first formulated in a recently proposed global task coordinate frame where the calculation of the contouring error is rather accurate and not affected by the curvature of the desired contour. A physical model based indirect type parameter estimation algorithm is then synthesized to obtain accurate on-line estimates of unknown physical model parameters. An integrated direct/indirect adaptive robust contouring controller with dynamic compensation type fast adaptation is also constructed to preserve the excellent transient and steady-state contouring performance of the direct adaptive robust control (DARC) designs. Comparative experimental results obtained on a high speed industrial biaxial precision gantry show that the proposed algorithm not only achieves the best contouring performance but also has accurate physical parameter estimations.