Design of passive joint in minimally invasive surgical robot

Several passive joints are usually needed in surgical robots to decrease the difficulty in doctors´ operating, which can be manually rotated without motor pushing. When stopped at a specified position, passive joints should be locked until operation ends, and keep bearing torques. This paper is aimed to design a locking method used in minimally invasive surgical robot. Firstly choose the locking type based on the technical requirements, and then the dimension can be determined using friction theory. Before finishing this design, the structure is verified by simulation. Not only the traditional method is used in the paper, but also new method combined with simulation is applied. As a result, the structure is much more reasonable, and will be the foundation for the following study.