1. University of Illinois at Urbana-Champaign,Department of Mechanical Science and Engineering,IL,USA,61801
2. Swiss Federal Institute of Technology (ETH Zurich),Automatic Control Laboratory,Zurich,Switzerland,8092
3. University of Illinois at Urbana-Champaign,Department of Agriculture and Biological Engineering Sciences,IL,USA,61801
4. North Carolina Agricultural and Technical State University,NC,27411