UCLA

The advancing frontier of modern robotics has enabled the automation of dental implant surgery, which also invokes the problem of physical Human-Robot Interaction (pHRI) in the clinical environment. In this dissertation, the concern for pHRI is integrated into the design of a robot implant surgery system including identification of patient status, AI decisions upon patient status, and real-time control to execute decisions. The behavior of human surgeon and patient is investigated and a system structure that reacts to potential motion of the patient during the surgical tasks is proposed. The effectiveness of patient status identification and AI decision is verified via simulation and the control algorithm is simulated and tested with Denso VM industrial arm, ATI force sensor, Nobel Biocare OsseoSet drilling unit, Denso b-CAP and Microsoft Visual Studio C++ programming environment. A total of 9 sets of simulations and experiments are designed covering the 3 tracking states plus 6 cases of switching among the 3 states. A prototype system is then built with control testing setup with an Microscribe MX digitizer and its behavior examined.Robotic technology can take advantage of high precision and repeatability in boosting the quality of tooth preparation, but is facing problems in generating the trajectory with irregular shape of tooth under constraints of clinical considerations as well. The design of the trajectory must conserve as much original contour as possible while creating sufficient large margin for an effective and lasting crown. In the meanwhile, the high precision requirement of the robot arm prefers a small motion range while the limited oral space demands the tool to avoid collision with soft issues and adjacent tooth. In this dissertation, a full coverage tooth preparation trajectory is generated in axial reduction and occlusal reduction. The axial reduction trajectory conserves the original contour, creates a taper angle of 1.4⁰ and minimizes the robot motion range in the oral space. Two solutions are proposed for occlusal reduction. A V-shape cut prepares the tooth by following the principal direction to conserve the basic contour, and a topographic cut targets a maximum conservation of the original occlusal surface. The trajectories are tested by cutting a 3D printed model by air turbine driven handpiece, held by a Meca 500 robot. The test results verify that the trajectory design is successful in preparing the tooth by conserving the original contour and the clinical design considerations. Teleoperation control in vitreoretinal surgery demands high precision and swift response. The unique environment of constrained task space yields to the issue of operation method to control the tool tip. In this study, we study two control methods for teleoperation vitreoretinal surgery in a virtual reality (VR) simulated environment with a surgical cockpit, master control arm and Oculus Rift S head mount. System is programed via Microsoft C#, Blender, Unity and Chai3D. The impact on performance with different scaling factors is studied as well to investigate the optimal parameter setting for vitreoretinal surgical teleoperation control. All the results in this dissertation are verified in simulations and experiments. The methodology, experiment equipment, data and observations from the experiment can be utilized in the development or as inspiration of the future investigation.