Deri altı iğneli müdahaleler için paralel robot dizaynı ve modellenmesi

Percutaneous needle operations need precise positioning in order to collect samples for diagnosis. Due to their robustness, accuracy robotic systems started to take place in medical procedures. Research that have been done until today showed that the robotic systems increase the accuracy of the medical interventions. This thesis presents the design and modeling of a 5DOF parallel robot that is used to conduct biopsies on human bodies, mostly focusing on the abdominal region. Ozyegin Biopsy Robot (OBR) consists of 3 stages; front stage, back stage and syringe mechanism. Front stage has 2-DOF and was designed to orient the needle and it serves as a guidance during needle insertion. Back stage has 3-DOF and duty of the back stage is to control the orientation of the needle and to perform the needle insertion. Syringe mechanism was designed to collect samples from body after the needle insertion. Necessary workspace and torque analyses were conducted in order to design the robot. Kinematic calculations were performed to find accurate needle tip position. Dynamic equations of motion were derived and system identification was performed on the robot to find the dynamics of system. With the calibration procedures, needle tip accuracy was aimed to be increased. For creating robust and accurate controllers, gravity compensation and friction modeling were implemented on the robot. Three different controller were created; PID controller, pole placement controller and torque computed controller. Results showed that torque computed controller reaches submilimeter needle tip accuracy and was verified as a robust controller for the system.