Abstract: Bone connection with robot is an important topic in the research of robot assisted fracture reduction surgery. With the method to achieve bone-robot connection in current robots, requirements on reliability and low trauma can not be satisfied at the same time. In this paper, the design, manufacturing, and experiments of a novel Bone Connection Robotic Hand (BCRH) with variable stiffness capability are carried out through the bionics research on human hand and the principle of particle jamming. BCRH’s variable stiffness characteristic is a special connection between “hard connection” and “soft connection”, which is different from the existing researches. It maximizes the reliability of bone-robot connection while minimizes trauma, meets the axial load requirement in clinical practice, and effectively shortens the operating time to less than 40 s (for mode 1) or 2 min (for mode 2). Meanwhile, a theoretical analysis of bone-robot connection failure based on particle jamming is carried out to provide references for the research in this paper and other related studies.

Key words: bone fracture reduction surgery, surgical robot, bone-robot connection, robot assisted surgery, orthopedic surgery