Grinding Process Stabilization with Active Modules

An efficient machine tool is characterized by high production quality, processing velocity, reliability as well as flexibility. Generally, higher velocities lead to increased process forces. This is especially noticeable in grinding, where the dynamic stiffness of a machine influences the process stability enormously. Unfavourable specification combinations of the grinding wheel, the condition of the workpiece and machine parameters lead to chatter vibrations of the machine, which results in chatter marks on the workpiece. Chattering is simply a consequence of vibration within a grinding system. At present, parts of the machine tools are improved continuously. However, a better performance can only be achieved by applying innovative basic approaches. In this paper, a grinding machine with integrated active modules is presented. The aim of these modules are to increase the static and dynamic stiffness of the structure which will thus minimize vibrations. The results of experimental and theoretical investigations on the vibration behaviour of a grinding machine and the design of active modules are shown. Control concepts to minimize forced and self-excited vibrations are presented and experiments were conducted to validate these concepts.