Mechanism Design And Master-Slave Mapping Strategy Of Minimally Invasive Surgical Robot

In according to the demands of the high-end treatment equipments, combiningthe basic theories and key technologies of surgical robots and taking the minimallyinvasive abdominal surgery as the typical application, a prototype of the integratedmater-slave Minimally Invasive Surgery (MIS) Robot has been developed and thefollowing contributions have been made in this dissertation.A novel configuration which meets the requirements of the incision positionconstrains of MIS is presented. With the optimal design under the workspace/bodyvolume ratio constraint, the system achieves optimal overall kinematic performancewith smaller size. This mechanism has been successfully applied in the master-slaveMIS robot "MicroHand A" system which is the first MIS robot in China.By generalizing the intersection of motion planes, that are the constitutingfeature of the classic Sarrus mechanism, a new Remote Center of Motion (RCM)mechanism type synthesis method is proposed. The basic principle of the typesynthesis method is to combine special planar mechanisms with their intersectingmotion planes free to tilt. The line of intersection passes through a fixed pointrepresenting the RCM. Several new two degrees of freedom (DoF) spatial RCMmechanisms as well as two three DoF overconstraint RCM mechanisms designedaccording to the proposed method.To guide the initial set-up of the robot before surgery, an optimization processfor MIS Robots with two passive joints is established. The pose of the robot relativeto the incision and the task-space is optimized by maximizing the global conditionnumber and meeting a set of performance constraints. The calculation results verifythe effectiveness of the technique in robot-assisted MIS.In allusion to the existing difficulties in performing the traditional MIS, Intuitivecontrol strategy, relative motion control strategy and scaling control strategy are founded to map the motion between the master and the slave. MIS requirements aremet and problems encountered in traditional MIS are overcome. Then, the method ofestablishing the desired motion relationship between the master and the associatedslave as viewed in the image device is provided.To ensure the smoothness and the safety of assisting MIS, reliable and effectivemanual interventions are established. A guided tool movement algorithm is developedto guide the tool exchange during the robot-assisted MIS. Finally, the electricalsecurity is strengthened to guarantee the use of the robot.In the field of novel MIS robot system design, an integrated system is proposedcreatively. Master manipulators, slave manipulators, image display device, andcontrol system have been designed and integrated into a novel system. Detaileddesign of the subsystems of the system is also provided. Further, stimulated by thedemands of rapid and valid treatment of common disease in China, the bloodless cutoperation scheme for the solid organs is presented, and the dedicated instruments forperforming this operation is developed.Experiments have been carried out to test the function of the robot. Theseexperiments include the mapping frequency, motion delay, operation force, and thevalidation of the control strategies and the manual interventions. The tissueexperiment has also been carried out in vitro to test the proposed bloodless cut.Finally, the animal experiment is performed, and the results show that the robot cancomplete the operation well. All of these verify the effectiveness of the design methodproposed in the dissertation.