Study On Assistant Laparoscopic Surgical Robot With Active And Passive Joints

Assistant laparoscopic surgical robot is used for taking place of the work of assistant surgeon who can achieve the control of laparoscopic position and orientation in the laparoscopic surgery. According to the order of surgeon, the robot can control the position and orientation of laparoscope to get stable and clear image of patient's lesion. The application of assistant laparoscopic surgical robot can not only reduce work intensity of the assistant surgeon, but also improve the output image quality and laparoscopic surgical efficiency. At present, laparoscopic surgery has been widely used. As people pay more and more attention to their own disease diagnosis and treatment, the assistant laparoscopic surgical robot will have broad application prospects in medical services in the future.This paper mainly researches the technology of assistant laparoscopic surgical robot with active and passive joints, including mechanical structure design, drive and control system design, kinematics analysis of active and passive robot, analysis of work space and configuration space of the laparoscope, work area planning, laparoscopic puncture location based on image navigation, mechanical analysis of man-machine system, etc. Experimental prototype of the robot has been developed, and its experimental study has been also carried out.A new type structure of assistant laparoscopic surgical robot with active and passive joints was put forward, and the characteristic of the structure and working principle were introduced. Prototype of the robot has been developed, and its drive and control system has been also designed.Kinematics equation of the active and passive surgical robot was established according to the relative coordinates of the puncture in the basis coordinate. The inverse solution of laparoscopic cone work space and the inverse solution of laparoscopic axial displacement were separately solved. The work space, configuration space of the laparoscope and the configuration space of laparoscopic lens axis which was controlled by the robot have been studied. The movement of laparoscope which controlled by the robot to observe patient's lesion followed by surgeon's order and the change of the attitude of laparoscopic lens axis were studied. The spatial arrangement of the robot, patient and laparoscope was analyzed, and the work space of robot has been planned.A new method of puncture location based on image navigation was proposed. Through two red lasers and a mirco-CCD camera, the position of laparoscopic puncture in the robot-based coordinate system was located. The robot can get the position and gesture information of the laparoscope by geometric relationship, so that it can control the laparoscope exactly. The location model of laparoscopic puncture was established, and the method of robot automatically searching and locating was studied.Abdominal-wall-puncture model and the robot model which were both based on ADAMS were built. After the artificial pneumoperitoneum was built, the force of abdominal wall during patient's breath was analyzed, before the laparoscope have entered into patient's peritoneal. The force of abdominal wall during the work process of the robot controlling the laparoscope was also analyzed. Its safety of the assistant laparoscopic surgical robot participated in laparoscopic operation was assessed. The mechanical properties of passive joints of the robot were analyzed; Its pre-tightening force was optimized to ensure that the passive joints have higher flexibility and the ability to overcome the interference of patient's breath to the laparoscope.The prototype of the assistant laparoscopic surgical robot with the active and passive joints was developed; Its drive system selection and control system architecture were introduced. Experimental research of the robot has finished, including the experiments of CCD micro-camera distortion correction, laparoscopic puncture position location and the simulated laparoscopic surgery experiment in which the robot participated. Feasibility of the assistant laparoscopic surgical robot with active and passive joints has been verified by those experiments.