Influence of Kinematic Perturbations on Shape-generating Movement Trajectory Stability

The article considers the influence of kinematic perturbations on stability of the tool shape-generating movement trajectory on the part of the turning machine executive element. The case of a lengthwise turning is considered. The trajectories of shape-generating movement consist of machine actuators motion trajectories and tool tip and detail elastic deformations displacements relative to the machine carrier system. The perturbations of machine actuators motion trajectories are determined by kinematic disturbance which depends on the accuracy and the state of the cutting-machine tool. They are determined by radial and axial spindle beating and speed variations of the support drive longitudinal movement in relation to the ideal axis of rotation parts and its displacement coordinates. Mathematical models of the cutting process perturbed dynamics are shown. By means of numerical simulation, it was shown that kinematic perturbations fundamentally alter the stability properties of the stationary shape-generating movement trajectories by parametric self-excitation.