Needle Insertion Strategies And Experiments Rearch Of Puncture Surgery Robot For Cranio-maxillofacial Tumors

The location of cranio-maxillofacial tumors involves the important nerve blood vessels and anatomical structure,hard to be removed,easy recurrence and demands high precision and stability. But the traditional puncture biopsy and radioactive particles implantation surgery were very complicate and high risk in the treatment of cranial and maxillofacial tumor. So imported the robot technology into cranial and maxillofacial surgery, established robot system with optical navigation device, control system of force feedback, image processing and surgery robot. To realize biopsies and radioactive particles implantation surgery for cranial and maxillofacial tumor, cut the workload for doctors, and achieve the goal of reduce the impact of human factors, decrease the difficulty of operation and improve the accuracy and quality. The main contents are as follows:Firstly, by analyzing the operation method of cranial and maxillofacial tumors, the robot system according to the necessary of the surgery was designed, and the mechanical structure of radioactive particles implantation device and common interface were developed. and the corresponding detail surgical methods and steps were proposed.Secondly, the kinematics model for the medical robot was established and solved. the registration among the four coordinate systems which make up the surgical navigation system was finished.Thirdly, positioning accuracy of robot was modeled and analyzed, D-H parameter modified model was established to calibration the robot parameters. Navigation space registration accuracy of the thesis was analyzed and established error transmission model of navigation space registration. Finally, the methods to improve accuracy of robot insertion accuracy were introduced.Fourthly, force interaction between soft tissues and needle were analyzed in the process of puncture by robot. Then the needle force was studied under different speeds of needle insertion, established the needle body bending deformation estimation equation and its correctness verified by experiments. Finally, the needle insertion strategies of the robot were proposed based on the force needle body bending deformation when the needles were inserted into soft tissue.Finally, set up the experiment platform for the robot system. Then experiments of calibration, robot positioning accuracy, space registration accuracy and insertion surgery accuracy were conducted. Finally, the experiments of puncture biopsy and radioactive particles implantation surgery were completed, and the experiments results were analyzed.