Adaptive dead-time compensation with application to a robotic welding system

The paper proposes a paradigm for control design suitable for poorly modeled plants with significant dead-time. An adaptive dead-time compensator is developed which is substantially different to the standard Smith predictor, and more generally applicable in practice. A framework is developed for selecting the controller parameters using now standard design techniques such as μ-synthesis. It is argued that adaptation allows for exact set point matching without the need for integration in the control law. Stability and convergence results are established for the resulting closed-loop system equations. The proposed adaptive dead-time compensator is compared with both a standard robust controller and an adaptive pole placement controller through experiments on a gas metal arc welding testbed