Novel Core Technologies and Systems for Magnetic Resonance Compatible Robotics

This dissertation presents design and validation of several systems and technologies for magnetic resonance imaging (MRI) compatible positioning. The research began as the development of an MRI compatible actuated phantom, which required precise motion through remote actuation. The phantom, which operates from 18 remotely actuated stepper motors, provided motion inside the MRI scanner with submilimeter accuracy and minimal zipper artifacts induced to the images. The motion requirements lead of the phantom project led to the development of a closed-loop motor controller which enabled such accuracy. Maximum absolute error of the tracking a sigmoid function was 0.012 rad, four times the precision of the motor itself. Through the process of developing the actuated phantom, ideas for a flexible, intrinsically MRI compatible method of force transmission were transformed into the Solid Media Flexible Transmission (SMFT) technology presented which can provide force transmission to an end effector up to 4 meters away from the remote actuator without the use of electrically conductive or magnetically susceptible materials. A tool positioning robot was built to demonstrate the technology and SNR reduction of as little as 5% was achieved by filtering the motor drive signals. The methods and experiments provided within demonstrate that traditional electromagnetic motors can be used inside the MRI room with better kinematic results than pneumatic or hydraulic systems and higher force output than piezoelectric motors with the use of the novel SMFT force transmission method.

Name thesis:degree_name

Doctor of Philosophy

Level thesis:degree_level

Doctoral

Discipline thesis:degree_discipline

Robotics

Grantor

University of Houston

Year dc:date.issued

2013

Author dc:creator

• Von Sternberg, Nicholas Craig 1986-

Advisors dc:contributor.advisor

• Ogmen, Haluk
• Tsekos, Nikolaos V.

Committee members dc:contributor.committeemember

• Contreras-Vidal, Jose L.
• Chen, Yuhua
• Stafford, R. Jason

• MRI-compatible robotics
• MR Compatible Actuation
• Solid Media Flexible Transmission
• Robotic Surgery
• Magnetic resonance imaging

Statement dc:rights

• The author of this work is the copyright owner. UH Libraries and the Texas Digital Library have their permission to store and provide access to this work. Further transmission, reproduction, or presentation of this work is prohibited except with permission of the author(s).

Language dc:language.iso

eng

Handle dc:identifier.uri

https://hdl.handle.net/10657/4097

OAI identifier oai:identifier

oai:uh-ir.tdl.org:10657/4097