1. School of Mechanical Engineering and Automation, Beijing University of Aeronautics and Astronautics�� Beijing 100083, China;
2. Dept. of Mechanical��Electrical Engineering, Zhengzhou Institute of Aeronautical Industry Management, Zhengzhou 450015, China
Minimal invasive surgery assisted robot was developed in Robotics Institute in Beijing University of Aeronautics and Astronautics. Based on the requirement of neurological stereotactic surgery, dexterity of the robot was analyzed. Firstly, using concept of service sphere and service section, definition of dexterity was proposed at any point inside the workspace of the five degree-of-freedom robot; then, analysis method of workspace dexterity was proposed. Dexterity distribution within the workspace was given using numerical analysis and graphical display, and the result was verified through experiment on the robot physical prototype. With the help of dexterity distribution in workspace, reliable reference can be supplied for surgery operation planning.