Exploiture Design And Research On The Key Technology Of 5-DOF-5-Swivel-Joint Parallel Machine Tool

Parallel Machine Tool (PMT) is a creative application of multi-loop mechanism in the field of machine manufacturing. This new-style machine tool perfectly complements the function of a traditional NC machine tool. The emergence of Parallel Machine Tool is accompanied with the development of theoretical research on parallel mechanism and computer software and hardware techniques. It is the result of combining mechanism theory, robotic techniques, numerical control techniques with mechanical structure techniques. Its prototype is Stewart Platform Mechanism. Parallel Machine Tool overcomes the disadvantages of a traditional NC machine tool which gets low stiff weight and low bearing capability, etc. It possesses many merits such as high stiff weight, high response speed, wide adaptability and easy multi-axis linkage, etc. With the development of the PMT technology, attention has been paid to the problems which always exist, such as the need of newly-designed 5-DOF structure, the lack of working space compared to the big size and the limit of attitude angles. The scholars all over the world put forward many improving methods. The potential of new PMT is gradually showed. The biggest advantage of the 5-axis PMT studied in the paper is to realize the deflection angle which is beyond 90°. It enables PMT's five-side machining in one time. In this paper, the application methods on developing new machine tools with virtual design are investigated. Systemic process of conceptive design and modeling digital prototype which examines design quality by simulation are summarized. A way to innovate a new machine is also put forward in the thesis. The main contributions read as follows:In this paper, the inverse kinematical solutions and mathematical models of the 5-DOF Parallel Machine Tool are presented. The 5-DOF Parallel Machine Tool has five degrees of freedom. It uses five swivels instead of fixed joints, whose angle restriction limits the maximum angles of inclination of the movable spindle. Because of the unknown location of joints, the inverse kinematical problem is different from the 6-DOF Stewart Parallel Mechanism or others. The inverse solution of the velocity is analyzed. The kinematical inverse solution equation and the velocity equation are deduced. The 5x5 Jacobian matrix of the PMT is established to describe the kinematical performances , such as dexterity and singularity, in brief.