Switched Amplifier-Driven Nanopositioning: Integrating System Modeling and Control Tuning

This article presents the integrated mechatronic and control design of a switched current amplifier-driven high-precision positioning system. An optimization-based parameter tuning process for a highly integrated state-control structure is proposed, including both dynamic requirements and target positioning uncertainty. This is enabled by a dynamic error budgeting analysis in the frequency domain, which is used to estimate position error contributions of the dominant error sources in the control system. The theoretical results are validated in practical experiments on a built prototype system, revealing a steady-state positioning uncertainty of 0.6 nm (rms) and fast reference position tracking with a rise time of 0.64 ms. Additionally, 17% less overshoot in comparison with classical loop-shaping cascade controllers is demonstrated.