Kinematics of a wrist based on spherical gear & ring-rack. - Qiang Li; Cunyun Pan; Xiang Zhang (ROBIO, 2009)

Analysis of unrestrained curve of rectangular piston ring based on energy principle. - Lei Zhang 006; Haijun Xu; Cunyun Pan; Xiang Zhang; Tengan Zou (ICARCV, 2014)