At the Interface Between Robots and Humans

By Elizabeth Thomson

When Sarah O’Meara arrived at UC Davis she had little experience writing software and had never conducted an experiment involving human subjects. Now, the mechanical and aerospace engineering doctoral student has a passion for both and is on track for a career that combines them in her research on robots that could one day lend a hand to astronauts and others operating under challenging conditions.

“I look at how you can design interfaces to connect humans and robotics in an integrated and high-performing way,” said O’Meara. Her ultimate goal: an assistive robot that a person can control by contracting a muscle or making a gesture. “Think of it as having a third arm that allows a single person to do a task that usually requires two people. That could be especially useful in extreme environments like space where personnel are limited,” she said.

O’Meara is working to achieve this goal using electromyography (EMG), in which electrical signals produced by muscles are used to control the movement of another object. These signals, which are captured via electrodes affixed to a given part of the body, are transmitted to a computer that analyzes them to determine the user’s intent and direct the movement of a device.

This work is so interdisciplinary that it straddles two UC Davis College of Engineering labs—those of Professors Stephen Robinson and Sanjay Joshi—who co-advise O’Meara. Among his research interests, Robinson, chair of the Department of Mechanical and Aerospace Engineering and a former astronaut, explores techniques for enhancing a person’s capabilities in extreme environments. Joshi is an expert on EMG control of prosthetic devices.

The two also encouraged O’Meara to apply for a NASA internship that has been very synergistic with her research. In 2017, she spent the fall in Houston working on a prototype robot for motion simulation that could allow astronauts to feel what it’s like to drive a rover on Mars. This experience prompted her to learn more about software back at UC Davis. O’Meara applied this newfound skillset by writing all the software for a preliminary study using EMG signals from human subjects to move a cursor on a computer screen. “It was the most complicated piece of software I’d ever written, and when it worked for the first time, I was very excited.”

Back at NASA this past summer, O’Meara built on that experience as a software architect for yet another robot. “So now I’m prepared to tackle the software challenges related to the next part of my doctoral work, which will involve using EMG signals to move an actual robot,” she said.

O’Meara emphasizes the importance of the many mentors who have encouraged her along the way. They include her parents, her NASA supervisors Asher Lieberman and David Read, and Professors Robinson and Joshi. “I wouldn’t have had these opportunities without all these people coming together and helping me,” she said.

That’s why she feels so strongly about the UC Davis outreach programs she coordinates and continues to develop. “I’ve had mentors who have maybe said just one thing to me, and it changed the trajectory of my career.”

In addition to managing outreach for Robinson’s lab, O’Meara is also involved in a program called SOAR, for STEM Outreach for Academic Reinforcement. The partnership between Robinson’s lab, the Aerospace Museum of California and Gateway Community Charter Schools aims to encourage fifth graders’ interest in science and technology by “having a sustained presence in their lives as mentors,” O’Meara said. The program, which began in late 2018, will include a kickoff, regular hands-on activities, and a wrap-up over the academic year.

How has UC Davis prepared O’Meara for the future? “The people I work with have supported and trained me so I can succeed at my research, and that has led to so many opportunities that I could never have originally imagined for myself.”