Design And Analysis Of Mammary Gland Clamping Flexible Manipulator

Mammary interventional surgery is of great significance in the diagnosis and treatment of breast diseases.Because of the fluidity of breast tissue,the focus will move with the breast tissue during puncture.Many interventional robots designed by researchers use two-dimensional compression plates to fix the breast tissue,which will cause great deformation of the breast,affect the surgical effect and reduce the comfort of patients.This paper aims to design a kind of flexible manipulator for breast clamping,which can fix the breast,adjust the location of the focus point and then puncture the needle in breast interventional surgery.Firstly,the functional requirements of the breast clamping flexible manipulator are summarized.The breast fixation module and the biopsy and puncture module were designed with the modular design idea.The mammary gland fixation module refers to the physiological structure of the human hand and designs the same four fingers that are driven by the tendon rope and distributed in a circle.Each finger has 3 rotational degrees of freedom and 1 lateral swing degree of freedom.The biopsy puncture module is designed with the function of quick needle change,and is connected to the base of the fixed module through bolts.The end of the flexible manipulator is connected to the UR5 e mechanical arm through the flange,and the mechanical arm drives the flexible manipulator to the proper position.Solid Words is used to model and render the breast clamped flexible manipulator.Secondly,the UR5 e manipulator and the link coordinate system of the flexible manipulator are established by using the D-H method,the kinematics equations are derived,and the forward and inverse kinematics solutions are obtained.Monte Carlo method is used to obtain the simulation image of the workspace through MATLAB software to verify that the workspace meets the needs of surgical operation.The puncture motion of the flexible manipulator is planned,and the motion sequence of each joint is defined.ANSYS was used to analyze the stress and strain of the key parts of the flexible manipulator to verify that the design of each mechanism was reasonable and the strength met the surgical requirements.ADAMS is used to simulate the motion process of fingers to verify the continuity of motion.Then,the manipulator controller system is designed according to the actual working requirements of the breast clamping flexible manipulator,STM32F103C8T6 is selected as the master control chip,and the main control circuit,I/O expansion circuit,motor drive circuit,etc.of the controller are designed to complete the hardware design of the controller system.The controller system software adopts Free RTOS embedded operating system as a whole,and the Free RTOS system is transplanted and verified to complete the program design of each task.The motor control program is designed using the position and speed cascade PID algorithm.The stability of the motor operation is verified by simulating the upper computer with Mini Balance software.Finally,the functional block diagram of the control system is planned,and the human-computer interface of the host computer system is built using QT.The parts of the3 D printing manipulator,combined with the control system,build an experimental platform to conduct experiments on the fixation of breast tissue,moving lesions and puncture effect of the manipulator.The experiment shows that the developed mammary gland clamping flexible manipulator has significant effects on the fixation of mammary gland tissue,the adjustment of the location of the focus and the puncture.The design of the structure and control system meet the requirements of breast interventional surgery,laying a good foundation for subsequent research and application.