1. Mem. ASME Department of Mechanical and Industrial Engineering, The University of Iowa, 218 Engineering Research Facility, Iowa City, IA 52242 e-mail:
2. Mem. ASME Department of Mechanical and Industrial Engineering, The University of Iowa, 2134 SC, Iowa City, IA 52242 e-mail:
3. US Army RDECOM/TARDEC, 6501 East 11 Mile Road, Warren, MI 48397 e-mail: