1. National Institute of Standards and Technology, Systems Integration Division, Gaithersburg, MD 20814 e-mail:
2. Department of Mechanical Engineering, University of Western Australia, Crawley, WA 6009, Australia e-mail:
3. GM Research and Development Center, Manufacturing Systems Research Lab, Warren, MI 48090 e-mail:
4. Department of Engineering Technology, Texas State University, San Marcos, TX 78666 e-mail:
5. Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109 e-mail: