Design And Implementation Of Laryngeal Minimally Invasive Surgery Robot System With Suturing Ability

In laryngeal minimally invasive surgery (LMIS), the surgeon employed the long laryngeal tools through constrained air-path to implement the whole therapy. Due to the restriction of the suspended Laryngeal's space, the current therapy can not implement complex operation. This dissertation designed a novel 7dof LMIS robot system. The LMIS robot worked in tele-operation mode and controlled by the surgeon through a remote master manipulator device. With the dexterous end effectors, the LMIS robot can implement suturing assignment under constrained space. The paper focused on the LMIS robot system design and implementation and made the following contributions.1. A novel mechanism was designed for LMIS robot. The LMIS robot was separated as end-effectors, active platform and passive arm three parts. In order to simplify its mechanism, the end-effectors'redundant joint coincided with open-close joint; the"Similar Crank-Slider"mechanism allowed the end-effectors possessed enough gripping force. The active platform employed a remote center mechanism to guarantee the safety of the trocar; meanwhile it can increase the register precision between robot and image by attaching them together. The passive arm designed with gravity compensation feature, which allowed surgeon easily position the robot in space.2. An online algorithm was presented to solve the redundant LMIS robot inverse kinematics problem. By perturbing end-effectors yaw joint with small displacement, the algorithm firstly generated multi redundant inverse kinematics solutions. And then ranked all the solutions followed by multiple redundant optimization criteria (ROC). Except for employing the existing ROC, one novel ROC followed the suspended Laryngeal's space restriction characteristic was introduced. The novel ROC can make use of the end-effectors redundant joint to avoid the collision between tools and suspended larynscopy, which guarantied the robot implement the suturing assignment in constrained space.3. The verification of the LMIS robot's capability of suturing in constrained space. Based on an open source toolkit, a virtual environment with LMIS robot and suspended laryngeal's model was built in computer. The virtual environment allowed debugging LMIS robot inverse kinematics algorithm and can verify the LMIS robot's capability of suturing in constrain space. Based on simulation result, LMIS robot inverse kinematics algorithm was implemented on LMIS robot prototype. Finally the LMIS robot's capability of suturing in constrain space was verified in reality.4. Design and implementation of a PC based the tele-controller for isomeric master and slave (m/s) manipulator. The controller designed with multi-level structure. The high-level algorithm employed the robot kinematics relative calculation and run on PC software level with low speed. In order to satisfy the robot control real time requirement, this algorithm maped the small variation instead of homogeneous transform between m/s to reduce calculation. The low-level algorithm computed robot trajectory planning and implemented by motion controller with high speed.At last, serial experiments have been done to evaluate the robot performance. After the experiment result complies with the design requirement, the LMIS robot implemented the suturing experiment in tele-operation mode. The experiment result showed the LMIS robot possessed the ability to apply in clinic environment.