1. Assistant Professor Department of Mechanical Engineering, San Diego State University, San Diego, CA 92115 e-mail: ;
2. Daniel L. Alspach Endowed Chair in Dynamic Systems and Control, Department of Mechanical and Aerospace Engineering, University of California, San Diego, San Diego, CA 92093 e-mail:
3. Mr. & Mrs. Robert F. Moritz, Sr. Endowed Chair Professor in Engineered Systems, Department of Mechanical Engineering, Villanova University, Villanova, PA 19085 e-mail: