Performance Evaluation of a Miniaturized Machining Center for Precision Manufacturing

Abstract

The ability to manufacture at the micrometric and even nanometric precision is in strong demand today in view of the increasing need to reduce the size of parts and products in many industrial and commercial sectors. For many of these applications, the technology of mechanical solid tool machining offers promising applicability as it can create truly three-dimensional and one-of-a-kind parts of extremely high resolutions without placing significant limitation on the part materials. For mechanical solid tool machining, the control of three-dimensional motions between machines, tools, and parts to sub-micron level of precision is a perquisite to the realization of manufacturing at such fine scales. One important factor that contributes to the machining process accuracy is the overall size of the machine tool due to the effects of thermal, static, and dynamic stabilities. This paper will assess the technological benefits of miniaturization of machine tools in the context of machine stiffness and accuracy. This paper also presents the design and configuration of a 4-axis miniaturized vertical machining center of positioning accuracy of 4 to 10 nm and a machine volumetric envelop less than 0.03m3, which is several hundred times smaller than traditional machining centers. A series of tests are discussed for performance evaluation of the miniaturized machining center in terms of the achievable finish and part form accuracy with respect to the process parameters and part geometrical complexity in 1-D, 2-D, and 3-D cases.