Kinematic analysis of partially decoupled fully-parallel manipulators of type 5-5 and 4-5

This paper presents two fully parallel manipulators of type 5-5 and 4-5 with special geometry that makes them partially decoupled. The direct kinematic analysis and the singularity study of these manipulators are addressed, which show that the motion of the manipulators can be easily controlled. Computational considerations are reported, which demonstrate that the algorithms proposed for the direct kinematic analysis are very efficient. Moreover, a comparison with other special geometries illustrates that the proposed manipulators are valuable solutions and represent a good compromise between an efficient controllability and a simple practical feasibility