1. Engineering Product Development, Singapore University of Technology and Design, 20 Dover Drive, Singapore 138682 e-mails: ;
2. Department of Mechanical Engineering, The University of Texas at Austin, 204 E. Dean Keeton St. C2200, Austin, TX 78712 e-mail:
3. Department of Mechanical Engineering, The University of Texas at Austin, 204 E. Dean Keeton Street, C2200, Austin, TX 78712 e-mail:
4. Department of Mechanical Engineering, Le Tourneau University, 2100 South Mobberly Avenue, Longview, TX 75602 e-mail:
5. Department of Engineering Mechanics, United States Air Force Academy, U.S. Air Force Academy, Colorado Springs, CO 80840 e-mial:
6. Engineering Product Development, Singapore University of Technology and Design, 20 Dover Drive, Singapore 138682 e-mail: