In multi-axis computer numerical control (CNC) machining, driving axes that are equipped with more degrees of freedom often cause singularities. Approaching singular points may cause the tool path to become unstable, where collisions occur between the tool and parts of the milling machine. Although singular points can be avoided through the rearrangement of appropriate paths and employing control methods to avoid singular points during application, or by designing mechanisms with more feasible handling to prevent the occurrence of approaching singular points, the best way is to generate the appropriate movements for each robust driving axis robustly and continually near singularities during working spaces. As the result of CL data are calculated in the CAM system it is assumed that the tool path between adjacent two CL points is regarded as a straight line relative to the work piece. In fact, due to the rotary axes of the machine, the tool path between two blocks in the NC program will drive the pivot to move non-linearly relative to the work piece, thus reducing the accuracy of the tool path. By using homogeneous transformation matrix, screw theory, modified D-H notation and Jacobian matrix, the kinematics and the singularity algorithm will be implemented in a postprocessor and be integrated directly in CAM system for developing novel postprocessor of the hybrid serial-parallel five-axis machining.
|Number of pages||7|
|Journal||Journal of Technology|
|Publication status||Published - 2016 Jan 1|
All Science Journal Classification (ASJC) codes