Improved servomechanism control design - Dynamically damped case

Time optimal control (TOC) for servomechanism is not a practical controller due to the chattering phenomenon that occurs on the presence of noise and model uncertainty. Maybe the most popular attempt to transform this controller in a practical one comes from the so called Proximate Time Optimal Servomechanism (PTOS). This approach starts with a near time optimal controller and then switches to a linear controller when the system output approaches the target. While the chattering phenomenon is avoided, this comes at an expense in performance generated by the so called “acceleration discount factor”. This paper will present a controller that makes use of dynamic damping in order to push the acceleration discount factor arbitrarily close to one, thus practically eliminating the conservatism present in the PTOS. Experimental results support the proposed design.