Ph.D. Proposal Presentation by Joel Fortgang
Thursday, March 17, 2005

(Dr. William Singhose, Chair)

"Combined Mechanical and Command Design for Micro-Milling Machines"


The utilization of micro-scale technologies is limited by the speed of

their manufacture. micro-milling, a manufacturing technique which employs the physical removal of material by a rotating bit, suffers from low throughput problems. The throughput can be increased by improving the speed of the positioning system if part tolerances can be maintained. However, simply increasing the operation speed will lead to vibration and trajectory following problems. Input shaping has proven effective in reducing vibration for fast moving systems, however no investigation has been conducted to determine the best mechanical components to use in conjunction with input shaping. If the positioning systems of micro-mills can be made lighter and faster by allowing increased flexibility, then input shaping might be able to deal with the flexibility, thus producing a faster positioning system capable of producing parts with the same or improved tolerances.

This leads to the primary research question of: How can the consideration of input shaping during the design phase create machine designs with improved performance?

In order to answer and clarify the primary question and show the benefits of considering mechanically flexible alternatives with input shaping for micro-mills, three important sub-questions must be answered. 1.What is the dynamic behavior of micro-mills when subject to commanded motion and/or cutting forces? 2. How can an input shaper be used not only to eliminate vibration but also to accurately track trajectories? 3. How can the performance of micro-mills be improved by selecting mechanical components and command profiles concurrently?