Date: April 7, 2026

Time: 9:00 am - 11:00 am EST

Location: McIntire Conference Room, Whitaker 3115

Virtual Link: https://gatech.zoom.us/j/91817181770

Timothy A. Brumfiel, Jr.

Robotics Ph.D. Candidate

Woodruff School of Mechanical Engineering

Georgia Institute of Technology

Committee:

Dr. Jaydev P. Desai (Advisor) 

Wallace H. Coulter Department of Biomedical Engineering

 Georgia Institute of Technology

Dr. Yue Chen 

Wallace H. Coulter Department of Biomedical Engineering

 Georgia Institute of Technology

Dr. Jun Ueda 

George W. Woodruff School of Mechanical Engineering

Georgia Institute of Technology

Dr. Levi Wood 

George W. Woodruff School of Mechanical Engineering

Georgia Institute of Technology

Dr. Zachary L. Bercu

Department of Radiology and Imaging Sciences

Emory University

Abstract:

Minimally invasive procedures utilize small incisions or natural orifices to perform surgery from within the body. This approach has the benefit of reduced patient trauma. However, manual navigation of the passive flexible devices utilized in these procedures is challenging in blood vessels with small diameters and extreme tortuosity or in regions with delicate surrounding structures, such as in neurosurgery. Continuum robots offer increased dexterity, compliance, and due to their simple structures, are highly miniaturizable, making them suitable for minimally invasive interventions. This work first focuses on a two degrees-of-freedom tendon-driven continuum robot tool for minimally invasive neurosurgery. The meso-scale tool is integrated with a robotic grasper for the manipulation of tissue, fiber optic strain sensors for shape and force sensing, and is evaluated by medical personnel within a phantom brain model. This work then focuses on sub-mm robotically steerable guidewires for endovascular interventions. Systematic design of the fabrication parameters is conducted, and a highly compact actuation mechanism is developed. The guidewire is further equipped with shape and force sensing through both fiber optics and imaging, and the feasibility of the device is tested in both phantom and in vivo animal models. Lastly, both active and passive stiffening of a robotic guidewire is conducted utilizing constant curvature and geometrically exact Cosserat rod-based modeling. A 0.5-5x change in stiffness for the active approach and a 37.26% increase in stiffness for the passive approach were achieved. Overall, this work demonstrates the capabilities of continuum robotic systems to provide enhanced dexterity, compact actuation, stiffness modulation, and improved safety for navigation in minimally invasive procedures.