Type synthesis and kinematic analysis for a class of mobile parallel robots

In this paper, a mechanism type synthesis is carried out for a class of mobile parallel robots (MPR) based on a systematic enumeration method, and the feasible configurations for the MPR are obtained. Then the inverse kinematics for the two typical mechanisms of PPRS and PPSR are derived. By a numerical approach, the workspace reachable in the Z-direction and the orientation workspace are obtained. The dexterity characteristics over the entire workspace of the proposed mechanism are investigated based on their condition number index. A comparison is given between the two typical mechanisms. This work provides a basis for the design of MPR mechanisms.