Jianchen Wang1, Shuxin Wang1, Jinhua Li1, Xiangyun Ren1, Randall Miller Briggs2. 1. Key Lab for Mechanism Theory and Equipment Design of Ministry of Education, School of Mechanical Engineering, Tianjin University, Tianjin, China. 2. Massachusetts Institute of Technology, Department of Mechanical Engineering, BioInstrumentation Laboratory, Cambridge, Massachusetts, USA.
Abstract
BACKGROUND: For current LESS robotic systems, the trade-off between dexterity and payload capability is always present. This paper presents a novel LESS robotic platform equipped with controllable stiffness manipulation arms. METHODS: Each manipulation arm with an articulated section and a controllable stiffness continuum section (CSCS) can be switched between a 7-DoF compliant status and 5-DoF rigid status according to the operation requirement. Screw theory and product exponential formula are used to quantify the kinematic performance. RESULTS: The stiffness of the manipulation arm promotes 3.03 to 4.12 times from compliant to rigid CSCS with maximum payload of 10 N in rigid status. The shortest rigid/compliant switching time is 5 s. The precision of a tracking test and an ex vivo procedure verified the accuracy and effectiveness of the controllable stiffness manipulation arms. CONCLUSIONS: This robot could potentially improve the surgical performance and further expand robotic LESS procedures.
BACKGROUND: For current LESS robotic systems, the trade-off between dexterity and payload capability is always present. This paper presents a novel LESS robotic platform equipped with controllable stiffness manipulation arms. METHODS: Each manipulation arm with an articulated section and a controllable stiffness continuum section (CSCS) can be switched between a 7-DoF compliant status and 5-DoF rigid status according to the operation requirement. Screw theory and product exponential formula are used to quantify the kinematic performance. RESULTS: The stiffness of the manipulation arm promotes 3.03 to 4.12 times from compliant to rigid CSCS with maximum payload of 10 N in rigid status. The shortest rigid/compliant switching time is 5 s. The precision of a tracking test and an ex vivo procedure verified the accuracy and effectiveness of the controllable stiffness manipulation arms. CONCLUSIONS: This robot could potentially improve the surgical performance and further expand robotic LESS procedures.
Authors: Manish Chauhan; James H Chandler; Animesh Jha; Venkataraman Subramaniam; Keith L Obstein; Pietro Valdastri Journal: Front Robot AI Date: 2021-05-10