A six-component contact force measurement device based on the Stewart platform

Abstract

This paper describes the design of a six-component contact force measuring device, the purpose of which is to verify a system of theories that predict the forces found in robotic grasping. The geometry of the device is based upon that of the Stewart platform manipulator, configured symmetrically. The elastic properties of the device as a whole, and of its legs, are analysed and chosen so that the device possesses appropriate characteristics. The resulting design is described, and its calibration and use are reported. Particular attention is paid to the synthesis of the elastic properties of the system, including an elastic central strut to maintain tension in the legs, which themselves are designed for acceptable sensitivity. The whole device is shown to give good results in contact force measurements.

Keywords

contact force measurement Stewart platform screw algebra stiffness force and torque transducers robotics grasping kinematics statics design

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