SUBJECT: Ph.D. Dissertation Defense
BY: Melih Turkseven
TIME: Friday, February 19, 2016, 10:30 a.m.
PLACE: Love Building, 210
TITLE: Modeling and Control of A Pneumatically Driven Haptic Interface For Rehabilitation in MRI
COMMITTEE: Dr. Jun Ueda, Chair (ME)
Dr. Michael Leamy (ME)
Dr. Nader Sadegh (ME)
Dr. Ayanna Howard (ECE)
Dr. Fumin Zhang (ECE)


This study presents a pneumatically driven haptic interface for rehabilitation in MRI, and methods for understanding, modeling and control of tele-operated pneumatic actuators. Pneumatic actuators have excellent MRI-compatibility as opposed to conventional electro-mechanic systems. They are also desirable for their inherent compliance and easy-maintenance. However, the actuator and the system drivers cannot be co-located due to the MRI-compatibility requirements. The actuators are driven via long transmission lines, which affect the system dynamics significantly. This thesis identifies the challenges in the tele-operation of the pneumatic actuators and introduces novel approaches to mitigate the adverse effects of long transmission in pneumatic drive. Methods provided in this work produced accurate pressure estimation and control by accounting for the pressure dynamics in the lines, which has been neglected by previous work in this area. The effectiveness of the presented modeling and control methods were demonstrated on tele-operation test setups. This work includes the design of necessary system components for the developed algorithms as well. Based on the outcomes of the study on the system dynamics, a MRI-compatible optical sensor was developed for force feedback. An analysis on the hysteresis characteristics of the sensor is presented.