| More than 500,000 people with brain hemorrhage experience hemiplegia,aphasia,and incapacitation after surgery.The main reasons for these phenomena are deviations between the brain patch out of the patient’s functional brain area and the actual condition of the patient’s functional brain area when the physician selects the brain puncture site;failure to follow the specified path;and the working sheath not reaching a specific location.To solve the above problems and predict the damage of the puncture trajectory to the patient’s functional brain area,this thesis uses augmented reality technology to help doctors understand the actual condition of the patient’s functional brain area and other brain structures,and control the robot to perform the puncture.This thesis focuses on the following aspects.(1)Accurate reconstruction of functional brain area models.The focus and difficulty of the 3D reconstruction of the patient’s brain structure are to complete the accurate reconstruction of the functional areas of the brain,which cannot be achieved by using traditional methods.To complete the accurate reconstruction of brain functional areas,this thesis firstly proposes an improved bilateral filtering technique with optimized processing of high-frequency noise,which solves the problem that high-frequency noise cannot be filtered out while preserving the detailed features of brain functional areas.Second,an improved watershed segmentation algorithm that can automatically determine the grayscale threshold is proposed to solve the problem of requiring professionals to set the threshold and over-segmentation based on experience when segmenting functional brain regions.The patient’s CT images were successively processed by the improved bilateral filtering algorithm and the improved watershed algorithm,and then the patient’s functional brain regions as well as other brain structure models were accurately reconstructed using the improved face mapping algorithm based on similarity region segmentation.(2)Research on the augmented reality-based navigation system.In this thesis,we first built an augmented reality environment,studied human-machine voice interaction and human-machine gesture interaction,and added spatial perception and path display functions to the augmented reality environment.Secondly,an improved ICP alignment method based on the SURF operator is used to complete the static registration of the virtual model to improve the accuracy and speed of 3D registration,and the effect of the improved algorithm is verified.Finally,the tracking registration of the working sheath model is completed based on the TCP points fed back from the robot.(3)Research on the high-precision control strategy of the brain hematoma removal robot.To improve the motion control accuracy of the robot,the control strategy of the brain hematoma removal robot is investigated in this thesis.The error in the angle of rotation of the robot joints affects the accuracy of the robot movement.In this thesis,the rotation angle error of the robot joints is compensated and a fuzzy PID control algorithm is added to the robot controller to ensure that the robot can move according to the planned route.(4)Effectiveness verification.This thesis first validates the effectiveness of augmented reality technology for surgery by displaying a structural model of the patient’s brain containing functional areas of the brain,real-time tracking of the working sheath,and displaying the planned path in an augmented reality environment.Secondly,the new control strategy of the robot was verified.The original control strategy of the robot and the new control strategy were used to control the robot for motion,and the effectiveness of the new control strategy was verified by comparing the deviation of the measured points on the motion trajectory. |
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