Dynamic Analysis of Horizontal Servo System in Suspension Gravity Compensation System

Abstract

A new suspension gravity compensation system has been developed to alleviate the gravity effects on a twodimensional(2D)deployable mechanism for ground verification. Considering the rigid-flexible coupling of both the rotating servo and the suspension system, a multi-body dynamic model simulating their integration is established using Lagrange's equation. To mitigate instantaneous impact forces due to significant non-plumb effects from passive following in the horizontal direction, an elastic element is added in series with the rope in the vertical suspension system. The dynamic response of this elastic element relative to the rotating servo system is analyzed by the ADAMS software. Simulation results show that the compensating error decreases significantly from 45% to 0. 31% when incorporating elastic elements compared to scenarios without such elements. Additionally, low-stiffness elastic elements demonstrate a higher compensating error than high-stiffness ones. A spring with a stiffness coefficient of 6 N/mm is selected in the experiment, ensuring that compensating error meets the design specification of 5%.

Keywords

suspension gravity compensation / passive servo system / flexible-rigid coupling model / series elastic element

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