Laser interferometry-based motion control of a flexure-based planar micro/nano mechanism

The rapidly expanding fields of micro and nano engineering, biotechnology and medical sciences have exhibited a need for high-speed and ultra-precise positioning systems. Piezo-driven flexure-based manipulators are most commonly utilised in the area of precise positioning and manipulation. In order to establish effective motion control, the research in the field of micro/nano manipulation requires faster, sensitive, and precise measurement of the motion characteristics. This project was undertaken to study laser interferometry-based closed-loop motion tracking of piezo-actuated flexure-based planar micro/nano manipulators. This research also examines characteristics and control requirements of piezo-actuated flexure-based mechanisms and establishes closed-loop control schemes to track desired motion trajectories. Experimental characterisation of the developed laser interferometry-based sensing and measurement technique demonstrates precise and accurate measurement at the nano-scale. Design analysis and laser interferometry-based motion control of a flexure-based four-bar mechanism shows evidence of precise and accurate tracking of desired motion trajectories. A detailed study on mechanism design, computational analysis and experimental investigation of a 2-DOF mechanism designed to support micro/nano positioning and manipulation tasks was performed. The dynamics of the developed 2-DOF piezo-actuated flexure-based manipulator was established using experimental system identification. Feed-forward, compound and robust motion controllers were established to track desired motion trajectories of the 2-DOF flexure-based manipulator. The established flexure-based manipulators perform micro/nano positioning and manipulation tasks with precision and accuracy. The experimental results verify accurate and precise tracking of desired motion trajectories utilising laser interferometry-based control.