Analysis And Reserch On Continuous Machining Path Of Five-Axis Hybrid Machine Tool

Compared with the traditional parallel machines, the continuous machining paths of hybrid machine tool with deficient—rank parallel mechanism can hardly be intuitively judged. And there isn't a uniform theory about how to judge it, which causes obstacles for the spread of hybrid machine tools. In this paper, the continuous machining path of hybrid machine tools is studied, which can provide theoretical basis for the further study of the planning and control of continuous machining path of hybrid machine tool.Firstly, the sufficient and necessary conditions of continuous motion of a constrained rigid body are presented with the investigation into the derivative of the virtual coefficient. Then, taking 3-PSP, 2UPS-2RPS and 3-UPU as examples, the corresponding mathematical and geometric criteria of them are obtained and the sufficient and necessary conditions of continuous motion of constrained rigid body are specifically explained.Secondly, based on the analysis of the geometry conditions of continuous axes of 3UPS/UP parallel mechanism, the mathematical expressions of continuous axes of Tricept hybrid body are derived. And the relevant mappings are drawn. Then, the condition of continuous motion of Tripod hybrid machine tool, with better performance, is analyzed, and the continuous axes of it are compared with those of Tripod hybrid machine tool.Thirdly, several special tool paths which can be formed by continuous axes in the work space are drawn, and the judgement condition of whether the arc path is the continuous machining path of machine tool is presented, then, some arc machining paths in typical planes are discussed.Finally, taking the typical continuous machining paths as examples, the above conclusion can be verified by simulating with software. The work of this paper is of great guiding significance to the further study of the path planning of hybrid machine tools.