Study On Key Technologies Of Needle Insertion Diagnosis And Therapy Surgery Robotic System For Craniomaxillofacial

Puncture surgery has been widely adopted in the fields of biopsy and interventional therapy for its small trauma, less bleeding, less pain and quicker recovery. However, the complexity of anatomy and the concentration of the blood vessels and nerves in cranio-maxillofacial zone make it difficult and risky for the doctors to perform manual puncture surgery for its potential damage to the important blood vessels and nerves. To solve this problem, surgical robot provides viable technical support. Based on the China National High Technology Research and Development Program(863 Program) named ‘Precise Minimally Invasive Diagnosis and Therapy Surgical Robotic System for Skull Base and Face Side Deep Zone’, this paper aims to solve current problems of the puncture surgery for cranio-maxillofacial. A diagnosis and therapy surgical robotic system, which can assist doctors to perform such operations as maxillofacial tumor biopsy, maxillofacial tumor radioactive seed implantation and skull base trigeminal neuralgia radio frequency heat cure, is researched and developed in this paper. This paper focuses on the key technologies of needle insertion diagnosis and therapy surgical robotic system for cranio-maxillofacial. It includes the mechanism design and optimization, the design and implementation of master-slave control system based on force feedback, kinematics analysis and trajectory planning, control of the needle deflection of the soft tissue, experimental study etc. Specific innovative points are as follows:First, on the basis of robot configuration and demand for clinical surgery, a needle insertion diagnosis and therapy surgical robotic system for cranio-maxillofacial is proposed, The robotic system with “one body, three terminal” can assist doctors to implement three kinds of puncture surgery, namely maxillofacial tumor biopsy, maxillofacial tumor radioactive seed implantation and skull base trigeminal neuralgia radio frequency heat cure. What’s more, the forward and inverse kinematics and workspace were analyzed and the rationality of the design was verified. Furthermore, we developed a needle insertion diagnosis and therapy surgical robotic prototype system for cranio-maxillofacial with independent intellectual property rights. After a series of experiments, the prototype platform can meet the needs of the three kinds of puncture surgery, namely the steady operation, precise positioning and stable puncture aspects.Second, on the basis of demand for clinical and robot configuration, we provided the control system requirements of the needle insertion diagnosis and therapy surgical robotic system, proposed a distributed master-slave force feedback control system based on the CAN bus technology, and detailed the design and the implementation of the control system. We put forward a Cartesian space-based inverse Jacobi master-slave control method and Integral Separation PID control algorithm based on the need of bidirectional force feedback of the robot. From the perspective of a systematic analysis of the security of the entire robot system, we established a practical model of multi-layered security monitoring. Proven, the entire control system meets the design requirements which provide technical reference for the development of surgical robot.Third, the partial puncture caused by the interaction between needle and soft tissue is one of the major reasons for puncture error. Meanwhile, it is also a common problem during the puncture. To solve this problem, the interaction between needle and soft tissue was analyzed. On this basis, deviation due to bending the needle was quantitatively estimated. The estimating equation was given. A simulation model of soft tissue deformation with localized refinement was presented. When puncture path planning, target drift compensation were predicted. By analyzing the process of mosquitoes’ mouth puncture into the skin, and mosquitoes’ puncture vibration law, we proposed a deviation control technology on the basis of bionic behavior. Based on this, a vibration puncture device was designed. Experimental analysis was conducted to verify the effectiveness of the technology.Finally, we analyzed the causes of accuracy error of the needle insertion diagnosis and therapy surgical robotic system, presented the methods to reduce the robot error, and made parameter calibration and error compensation. After calibration of the robot prototype, we conducted repeat positioning accuracy test and absolute positioning accuracy test. Through the debugging experiment, maxillofacial tumor radioactive seed implantation experiment and skull puncture test, we verified the effectiveness of the whole system which laid a solid foundation for forming a stable, secure, and reliable surgical robot product.