Path control algorithms of a novel 5-DOF parallel machine tool

A novel 5-DOF PMT (parallel machine tool) is proposed, which has five driving limbs and a passive limb. It can perform three translational DOFs (degrees of freedom) and two rotational DOFs. The passive limb can act as not only a constraint chain, but also a measuring chain. Multi-axis simultaneous control must be performed and the mapping transformation of motion from the virtual to actual axis is the core of the control algorithms. The control algorithms, such as coarse interpolation of the tool path, the mapping transformation from the CL (cutter location) data to the length of driving axis, velocity control of the driving axis and pose measuring method of the tool, are analyzed in detail. The CNC system software based on the algorithms has been developed and applied to the novel 5-DOF PMT in our laboratory. The machining experiments are made and the better machining performance is achieved.