1. Mechanical Design Engineer, Interior Cockpit Dept., Tesla Motors, 45500 Fremont Blvd., Fremont, CA 94538; formerly, Univ. of Wisconsin–Madison, Madison, WI 53706.
2. Research General Engineer, USDA Forest Products Laboratory, Gifford Pinchot Dr., Madison, WI 53726.
3. Professor Emeritus, Dept. of Mechanical Engineering, Univ. of Wisconsin–Madison, Madison, WI 53706 (corresponding author).