TY - GEN
T1 - A Cable-Driven Redundant Spatial Manipulator with Improved Stiffness and Load Capacity
AU - Liu, Tianliang
AU - Mu, Zonggao
AU - Wang, Haomiao
AU - Xu, Wenfu
AU - Li, Yangmin
PY - 2018/12/27
Y1 - 2018/12/27
N2 - With a light and slender body, a cable-driven redundant spatial manipulator (CRSM) has flexible manipulability and high maneuverability in confined environment. However, compared with revolute rigid manipulators, such type of manipulators generally has low stiffness and weak load capacity. In this paper, we propose a new mechanism design to improve the stiffness and load capacity without sacrificing the manipulator dexterity and the end-effector accuracy. The manipulator is composed of 3 active-passive-linkage segments and 1 active tool end-effector. Each active-passive segment has 2 degrees of freedom (DOFs) driven by three evenly distributed cables. Pretension mechanism and linkage cables are designed to keep strict equal angles of adjacent joints. A separable control box, which contains all the motors and cable transmission mechanisms is also designed with a quick release-and-lock mechanism. Therefore, the robotic arm can be easily removed and installed. Based on the equal angle characteristic, kinematic equations of manipulator are established with Denavit-Hartenberg (D-H) method and the Jacobian matrix is also simplified. Further analysis of the workspace supplies the guidance for the task design and motion planning. Finally, a prototype system is developed to perform the stiffness and load capacity experiments. Experimental results show that the developed CRSM has relatively high stiffness and load capacity.
AB - With a light and slender body, a cable-driven redundant spatial manipulator (CRSM) has flexible manipulability and high maneuverability in confined environment. However, compared with revolute rigid manipulators, such type of manipulators generally has low stiffness and weak load capacity. In this paper, we propose a new mechanism design to improve the stiffness and load capacity without sacrificing the manipulator dexterity and the end-effector accuracy. The manipulator is composed of 3 active-passive-linkage segments and 1 active tool end-effector. Each active-passive segment has 2 degrees of freedom (DOFs) driven by three evenly distributed cables. Pretension mechanism and linkage cables are designed to keep strict equal angles of adjacent joints. A separable control box, which contains all the motors and cable transmission mechanisms is also designed with a quick release-and-lock mechanism. Therefore, the robotic arm can be easily removed and installed. Based on the equal angle characteristic, kinematic equations of manipulator are established with Denavit-Hartenberg (D-H) method and the Jacobian matrix is also simplified. Further analysis of the workspace supplies the guidance for the task design and motion planning. Finally, a prototype system is developed to perform the stiffness and load capacity experiments. Experimental results show that the developed CRSM has relatively high stiffness and load capacity.
KW - Cable-driven
KW - Kinematic
KW - Load capacity
KW - Redundant manipulator
KW - Stiffness
UR - http://www.scopus.com/inward/record.url?scp=85062974197&partnerID=8YFLogxK
U2 - 10.1109/IROS.2018.8593679
DO - 10.1109/IROS.2018.8593679
M3 - Conference article published in proceeding or book
AN - SCOPUS:85062974197
T3 - IEEE International Conference on Intelligent Robots and Systems
SP - 6628
EP - 6633
BT - 2018 IEEE/RSJ International Conference on Intelligent Robots and Systems, IROS 2018
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 2018 IEEE/RSJ International Conference on Intelligent Robots and Systems, IROS 2018
Y2 - 1 October 2018 through 5 October 2018
ER -