Dynamic Analysis of the KNTU CDRPM: A Cable Driven Redundant Parallel Manipulator

KNTU CDRPM is a cable driven redundant parallel manipulator, which is under investigation for possible high speed application such as 3D laser cutting machine. This newly developed mechanisms have several advantages compared to the conventional parable mechanisms. Its rotational motion range is relatively large, its redundancy improves safety for failure in cables, and its design is suitable for high acceleration motions. In this paper, the inverse kinematic analysis of this structure in is presented first, and then the Jacobian matrices of the manipulator are derived. Furthermore, the governing dynamic equation of motion of such structure is derived using the Newton- Euler formulation. Next, the dynamic equations of the system is used in simulations. It is shown that on the contrary to serial manipulators, dynamic equations of motion of parallel manipulators can be only represented implicitly, and only special integration routines can be used for their simulations. In order to verify the accuracy and integrity of the derived dynamics, open– and closed–loop simulations for the system is performed and analyzed. It is shown that high gain PD controllers are able to reduce the induced vibration caused by the cable structures in these manipulators.