Spatial-Temporal Trajectory Redesign for Dual-Stage Nanopositioning Systems

This paper focuses on trajectory redesign for dual-stage nanopositioning systems where speed, range, and resolution are considered. This approach differs from many existing approaches that consider only speed. Dual-stage nanopositioning systems are becoming increasingly popular due to their unique ability to achieve long-range and high-speed operation. However, typical control strategies rely on temporal (frequency-based) information to split the control effort between the two actuators, which can render some precision positioning trajectories unachievable. Building on the authors' previous work, a novel systematic spatial-temporal trajectory redesign process is presented, where the desired trajectory is first split based on achievable positioning bandwidth and then split spatially based on achievable range and positioning resolution. The split signals can then be followed by the dual-stage nanopositioner, where in this paper an inversion-based feedforward controller is used. This trajectory redesign process allows each actuator to fully utilize its bandwidth and range of motion. Simulation and experimental results are presented to demonstrate feasibility.