In the past recent years Parallel Kinematic Mechanisms (PKM) have attracted a lot of attention from academic andindustrial communities due to their potential applications not only as robot manipulators but also as machine tools. Traditionally, these systems are employed as flight simulators for pilot training or even people entertaining. From the analysis of their typical topologies, it can be observed that theyare composed by two or more closed kinematic chain mechanisms. In general, theydemonstrate a higher performance than serial kinematic mechanisms, once the last ones present deficiencies related to structural stiffness, load capacity and positioning accuracy. On the other hand, parallel kinematic mechanisms are much more rigid, accurate and have higher load capacity and, therefore, can be lighter. Besides, when these mechanisms are used as machine tools, they are able to produce workpieces with very complex geometries, giving shapes and surfaces which would be difficult to obtain from conventional or even NC machine tools. This article deals with a type of parallel kinematic mechanism with four degrees of mobilit y that allows positioning andorientation of the platform (table) that supports a pieceto be machined. This article also presents the mechanism mathematical model, describes the prototype built , shows technical specifications of its subsystems and comments its future applications.
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