Design and analysis of a piezo-actuated 2-DOF high-precision parallel pointing mechanism capable of carrying a heavy load

This paper presents the design, modeling, analysis, and test of a 2-degree-of-freedom (2-DOF) high-precision parallel pointing mechanism capable of carrying a heavy load up to 30 N.m driven by high voltage piezo-stack actuators (HVPSAs). The proposed pointing mechanism, which employs flexure hinges as joints, provides two tilting degrees of freedom and can be utilized for intersatellite optical communication, remote sensing satellite lens pointing, and other engineering fields requiring large load capability. In this paper different kinds of flexure hinges are utilized to achieve the desired motion and working performance. With consideration of most compliant elements, Castigliano's second theorem was adopted to establish the analytical static model of the mechanism, which was then validated by FEA simulation and experimental testing. Finally, a high-precision pointing prototype is fabricated and a series of motion performance tests have been implemented, which validated the feasibility of the proposed system. The superiority of the proposed design is that it possesses large load capacity as well as excellent pointing performance simultaneously, while the former characteristic was infrequently reported in previous works.