Yonggui Wang

Since the intricate anatomical structure of the craniomaxillofacial region and the limitation of surgical field and instrument, the current surgery is extremely of high risk and difficult to implement. The puncturing operations for biopsy, ablation, and brachytherapy have become vital method for disease diagnosis and treatment. Therefore, a craniomaxillofacial surgery robot system was developed to achieve accurate positioning of the puncture needle and automatic surgical operation. Master‐salve control and “kinematic + optics” hybrid automatic motion control based on navigation system, which is proposed in order to improve the needle positioning accuracy, were implemented for different processes of the operation. In addition, the kinematic simulation, kinematic parameters identification, positioning accuracy experiment (0.56 ± 0.21 mm), and phantom experiments (1.42 ± 0.33 mm, 1.62 ± 0.26 mm, and 1.41 ± 0.30 mm for biopsy, radiofrequency, and brachytherapy of phantom experiments) were conducted to verify the feasibility of the hybrid automatic control method and evaluate the function of the surgical robot system.

In view of the characteristics of high risk and high accuracy in cranio-maxillofacial surgery, we present a novel surgical robot system that can be used in a variety of surgeries. The surgical robot system can assist surgeons in completing biopsy of skull base lesions, radiofrequency thermocoagulation of the trigeminal ganglion, and radioactive particle implantation of skull base malignant tumors. This paper focuses on modelling and experimental analyses of the robot system based on navigation technology. Firstly, the transformation relationship between the subsystems is realized based on the quaternion and the iterative closest point registration algorithm. The hand-eye coordination model based on optical navigation is established to control the end effector of the robot moving to the target position along the planning path. The closed-loop control method, “kinematics + optics” hybrid motion control method, is presented to improve the positioning accuracy of the system. Secondly, the accuracy of the system model was tested by model experiments. And the feasibility of the closed-loop control method was verified by comparing the positioning accuracy before and after the application of the method. Finally, the skull model experiments were performed to evaluate the function of the surgical robot system. The results validate its feasibility and are consistent with the preoperative surgical planning.

The three-arm surgical robot system assisted mandible reconstruction surgery (TMR-MRS) is developed to repair the mandible defects caused by congenital defect, trauma, or acquired disease. The surgical robot system is divided into four parts, including 3D reconstructed image subsystem, robotic subsystem, optical measurement subsystem, and patient subsystem. The spatial registration based on quaternion is proposed to obtain the transformation relationship between four surgical subsystems. A method of hand-eye coordination is presented to control the end-effector of the robot arm to target position according to surgical planning. A least square error criterion is developed to optimize and compensate the hand-eye coordination method. In addition, the position of fibular implant in the robot space is calculated when it is grasped by end-effector of robot middle arm. Finally, the positioning accuracy tests and skull model experiments were conducted to evaluate the function of the surgical robot system. The results validate its feasibility and are consistent with the preoperative surgical planning.

To reduce labor intensity and irradiation exposure time inside the steam generator during the maintenance period of the nuclear power plant, a blocking plate manipulation robot system, including manipulation robot and pneumatic control console, is developed as an automatic remote-control tool to help staff to complete sealing steam generator primary pipes. The manipulation robot for fastening/loosening bolts utilizes visual guidance for target position, and the recognition algorithm is exerted to extract the bolt center coordinate values from image captured by camera in the procedure. The control strategy based on the position and current feedback is proposed for single bolt operation and whole bolts automatic operation. Meanwhile, the virtual interactive interface and remote monitoring are designed to improve the operability and safety. Finally, the relative experiments have verified the work effectiveness and the future work would be discussed.