My research interests are primarily in the fields of Robotics Grasping and Manipulation. I am interested in designing and integrating robots and tactile sensors to leverage the sense of touch and perform tasks more effectively. I believe robots will be useful in our homes to assist us in our every day tasks.
Exploratory Hand: Leveraging Safe Contact to Facilitate Manipulation in Cluttered Spaces
We present a new gripper and exploration approach that uses an exploratory finger with very low reflected inertia for probing and grasping objects quickly and safely in unstructured environments. Equipped with sensing and force control, the gripper allows a robot to leverage contact information to accurately estimate object location through a particle filtering algorithm and also grasp objects with location uncertainty based on a contact-first approach. This publication is still under review so it is not yet available.
A Stretchable Tactile Sleeve for Reaching into Cluttered Spaces
A highly conformable stretchable sensory skin made entirely of soft components. The skin uses pneumatic taxels and stretchable channels to conduct pressure signals to off-board MEMs pressure sensors. The skin is able to resolve forces down to 0.01N and responds to vibrations up to 200 Hz. We apply the skin to a 2 degree-of-freedom robotic wrist with intersecting axes for manipulation in constrained spaces, and show that it has sufficient sensitivity and bandwidth to detect the onset of sliding as the robot contacts objects. We demonstrate the skin in object acquisition tasks in a tightly constrained environment for which extraneous contacts are unavoidable.
A Mixed-Reality System for Breast Surgical Planning
We have developed a mixed-reality system that projects a 3D “hologram” of images from a breast MRI onto a patient using the Microsoft HoloLens. The goal of this system is to reduce the number of repeated surgeries by improving surgeons’ ability to determine tumor extent. We are conducting a pilot study in patients with palpable tumors that tests a surgeon’s ability to accurately identify the tumor location via mixed-reality visualization during surgical planning
Display of Needle Tip Contact Forces for Steering Guidance
A MR-compatible biopsy needle stylet is instrumented with optical fibers that provide information about contact conditions between the needle tip and organs or hard tissues such as bone or tumors. This information is rendered via a haptic display that uses ultrasonic motors to convey directional cues to users. Lateral haptic cues at the fingertips improve the targeting accuracy and success rate in penetrating a prostate phantom.
The Effect of Manipulator Gripper Stiffness on Teleoperated Task Performance
The absence of environment force sensing in robot-assisted minimally invasive surgery, makes it challenging for surgeons to perform tasks while applying a controlled force to not damage patient tissue. One way to help modulate grip force is to use a passive spring to resist the closing of the master-side gripper of the teleoperated system. To investigate the effect of this spring stiffness we developed a haptic device that can render a programmed gripper stiffnesses. We conducted a study in which subjects used our dvice to teleoperate a Raven II surgical robotic system in a pick-and-place task. We found that increasing the gripper stiffness resulted in reduced forces applied at the slave-side.