Research On Key Techniques Of Image Guided Transcranial Magnetic Stimulation Robot System

Transcranial magnetic stimulation is a non-invasive,non-radiative physical therapy that can be used to treat mental,neurological diseases.In our country,people pay more attention to organ diseases than mental diseases,and lack of professional psychiatric medical staff.Transcranial magnetic stimulation technology,as one of the "four brain sciences in the 21 st century",has many problems in clinical application,which restricts the clinical promotion and further development of this technology.In order to make transcranial magnetic stimulation treatment more precise and stable,reduce the influence of subjective experience factors,and reduce the labor intensity of operators,it is imperative to develop an image-based navigation robot system for transcranial magnetic stimulation treatment.The issue has not been resolved in China.This paper mainly studies the basic and key technologies of imageguided transcranial magnetic stimulation robot system,including the construction of image-guided transcranial magnetic stimulation robot experimental system,segmentation and 3D reconstruction of head MRI images,registration technique for real-time head and 3D reconstruction models of patients,hand-eye calibration technology for robot system,and control technology for transcranial magnetic stimulation robot.This paper introduces the experimental platform composition of the image-guided transcranial magnetic stimulation robot system,and introduces the workflow of the system.In this paper,the UR5,a lightweight six-joint robot commonly used in the industry,is used as the body of the transcranial magnetic stimulation robot.The UR5 has the advantages of flexibility and human-machine homology,and is very suitable for medical environments.This paper is mainly about the three-dimensional reconstruction of the head tissue including the brain tissue structure of the volunteer MRI image data.Due to the complexity of human brain tissue structure and low image contrast,it is difficult to automatically segment images.This paper uses Mimics19.0 medical modeling software,artificially intervenes image segmentation,and uses interactive semi-automatic segmentation to establish white matter and gray matter.Masks of the brain parenchyma,cerebellum,cerebrospinal fluid,scalp and skull.The region is continuously modified,3D magnetic lasso,Boolean operation and morphological operation are used to continuously correct the mask,repeatedly optimize,and finally reconstruct the "five-layer ball" head model containing the brain tissue structure.The 3D head model is transformed into a 3D point cloud,and the PCA algorithm is used for initial registration.Then the ICP algorithm is used for accurate registration.The point cloud registration experiment is carried out based on the matlab platform.The results show that the initial registration of the PCA algorithm combined with the accurate registration of the ICP algorithm can meet the head registration accuracy requirements.This paper establishes the forward kinematics and inverse kinematics model of the transcranial magnetic stimulation robot.Based on the ROS platform,the URDF file of UR5 is configured,and the MoveIt! tool is used to simulate the forward kinematics and inverse kinematics of UR5.The trajectory planning of UR5 joint space was carried out by cubic polynomial interpolation method.The UR5 joint space trajectory planning simulation,Cartesian space linear trajectory planning and circular trajectory planning were completed.The UR5 autonomous obstacle avoidance experiment simulation was carried out.In this paper,the calibration experiments of the transcranial magnetic stimulation robot system are carried out,including the calibration of color camera and infrared camera based on ROS,the design of robot end tool,the ROS-based transcranial magnetic stimulation robot hand-eye calibration experiment,and verification of the calibration results of the hand eye.The paper studies the key techniques of image-guided transcranial magnetic stimulation robot system,lays a foundation for the real realization of IRTMS treatment system.