Piezoelectric Planar Parallel Microrobot With High Bandwidth and Precision for Micromanipulation

Parallel micro/nano robots hold great potential in micro-manufacturing/assembly, microsurgery, and precision engineering because of their high precision and stiffness. However, it is challenging to develop a millimeter-scale robot with a large workspace, high bandwidth, and high precision. In this paper, we present the design, fabrication, tests, and potential applications of a piezoelectric planar parallel microrobot. The developed microrobot consists of a parallel mechanism, three amplification mechanisms, and three independently controlled piezoelectric actuators. The microrobot is miniaturized to the millimeter scale through a monolithic integrated manufacturing process, and achieves a dimension of 36 \times 36 \times 34 mm, a weight of 4.9 g, and a static workspace of 33.9 mm ^{2} . The resonant frequencies reach 55-65 Hz in x and y directions, and 95 Hz in rotation. The microrobot exhibits high positioning accuracy in the trajectory tracking experiment on three different lines, circle, and triangle trajectories at a board bandwidth. Moreover, the microrobot can repeat 50 periodic circle trajectories in one second, with a velocity of 628.3 mm/s and a precision of 10.9 \upmu m. Furthermore, we conducted three validation experiments to demonstrate the potential applications of the microrobot in tremor compensation for micromanipulation, 3D printing electronics, and minimally invasive surgery. Note to Practitioners -This work is motivated by the need to design a microrobot with a large workspace, high bandwidth, high precision, and compact structure. Such capabilities are essential across various fields of micromanipulation, including micro-manufacturing/assembly, microsurgery, and precision engineering. This paper presents a detailed manufacturing process for this type of microrobot, followed by comprehensive experimental tests. The resonant frequency, workspace, quasi-static and dynamic trajectory tracking experiments of the microrobot are thoroughly tested. The experimental results demonstrate the excellent performance of the microrobot in executing various operational tasks. Additionally, the potential applications in the fields of micromanipulation, 3D printing elec