Design and Kinematics Analysis of Oblique Axis Non-spherical 3R Wrist

A kind of novel hollow oblique axis non-spherical 3R wrist with inner-duct was designed to protect the lines going through the duct, such as paint tube, solvent tube, shaped-air tube and so on, from being knotted or broken during spray painting of car body. With compact structure and great flexibility, the wrist could realize three continuous rotational motions. Also, the kinematics analysis of this kind wrist was conducted. Equations of forward kinematics and inverse kinematics were deduced. Furthermore, simulation of kinematics was made to validate the feasibility of design scheme with ADAMS (Automatic Dynamic Analysis of Mechanical Systems) software. The simulation results were found to be in agreement with the theoretical calculation.