Research On Assistant Laparoscopic Surgical Robot Model And Its Simulation

Laparoscopic surgery has been rapidly developed for its advantages of small incision, little pain and quick postoperative recovery. Robots involved in laparoscopic surgery is a momentous revolution, and it has been matured in developed countries and has drew more and more attention in our country for the number of research institutions study in assistant laparoscopic surgery robot is increasing. As the continuous development of medical technology and the improvement of people's living standards, reseaches on laparoscopic surgical robot with independent intellectual property rights is imperative.This paper designed a new type of 6-DOF (Degrees of Freedom) robot with active-passive mode, which was based on the first generation of assistant laparoscopic surgery robot in the laboratory. Three active joints were driven by servo motors to realize the transformation of spatial positions of the robotic ends. The others were passive joints, worked with the photoelectric encoder to detect the position of the robot and accomplished the attitude change of the laparoscopic.The kinematics equation was established using D-H method. The robot's motion was simulated and analyzed by MATLAB software. The results showed the correctness of robot kinematics model, and it has laid the foundation for the control of robots. The robot workspace was analyzed in order to verify the structure of the assistant laparoscopic surgery robot could satisfy surgical space needs.The incision constraint simulation model was built based on the dynamic characteristics of human skin, and the impact of the damping coefficient of passive joints between the edge of the incision and the laparoscopy was analyzed. The flexibility of damping coefficient of the passive joints was determined to provid theoretical basis for the actual parameter. The control simulation model of robot was established to choose the control parameters of the active joints motor. The robot's trajectory was simulated, the results showed that the robot can track the trajectory accurately and the error was within the allowable range.