A design of an automated compact positioning system for workpiece positioning in machine tool workspace

摘要

The paper constitutes a study into the design of a novel type of a compact positioning system based on the constrained parallel mechanism. In this study, a design of low-height rotary table is presented for automated leveling, which can be mounted directly on the machine tool table without a significant decrease of the workspace. The authors propose a modification of parallel mechanism by introducing four extensible leg design and a table block which motion is constrained around a sphere in order to achieve higher rigidness. The table is driven by four hydraulic linear actuators which are connected with the linkages. Three different designs are discussed focusing on its capabilities of load transmission and compactness. The best solution was verified using FEM in order to test its potential rigidness and maximal contact stress occurring between interacting blocks. The designed model allows rotating the table about the sphere center using three independent rotations. The development of an automated compact positioning system can contribute to the reduction of manual time-consuming leveling operations without significant reduction of machine tool workspace.