摘要: Minimally invasive surgery(MIS)has the advantages of less trauma and quick recovery, so it is favored by patients. However, there are more requirements for surgeons' skill and experience in MIS. Combining robot-assisted tech-nology with MIS can improve the quality of surgery and shorten the learning time for surgeons. Besides, with the help of robot-assisted technology, remote surgery can be achieved. Because of small incisions in MIS, the manipu-lator must pass through a fixed point during movement, which is the key point to develop the MIS robot and an obvious feature of the MIS robots. The ways whose classification is made into mechanisms with redundant degrees of freedom (DOF) and constrained by mechanisms to meet the requirement are summarized, and the principles, advantages, and drawbacks of each method are analyzed in this article. Based on summarizing the research results and analyzing the key technologies, the insight into future work is proposed.