Haley Mayer (MIE PhD 2T5) says that the moment the clinical impact of her thesis research really ‘clicked’ was in February 2024 — the first time she observed a live surgery.
“I was working with a surgeon from Toronto Western Hospital, Dr. Eran Shlomovitz, and I was watching him try to cut out lesions endoscopically without any assistance whatsoever,” says Mayer.
“The surgery took three hours. It was then that I really understood the surgeon’s need for a tool to make it easier. My problem statement was right there in front of me, and the impact was so clear.”
Mayer, who just graduated last month, was co-supervised by Professor Eric Diller (MIE) and physician and researcher Dr. James Drake at the Hospital for Sick Children (SickKids).
During her master’s and PhD research, she focused on improving the design of surgical tools to help decrease tissue damage during invasive surgeries in areas like the brain and gut.
“We’re trying to make devices and tools as small as possible, while retaining all the accuracy and performance of current options,” says Mayer.
“They can reduce tissue damage, shorten recovery times and achieve better outcomes for patients.
But Mayer almost missed her calling.
“I spent my entire undergrad not taking any robotics courses, until fourth year,” says Mayer.
“In the course, we worked with industrial robots, and it reminded me how much I enjoyed playing with small robots when I was younger. So when it came to wanting to go to grad school, I thought: ‘what if I combined my childhood hobbies with my career passions?’”
Mayer found herself fascinated by the intersection of mechanical and biomedical engineering.
“It was the perfect bridge between what I enjoyed most and my career goals, which is engineering design and making an impact in society,” says Mayer.
Many of the tools created by Diller and his team work using magnetic actuation. The tiny forceps, scalpels or other tools contain magnets, which are then manipulated by varying the strength and orientation of external magnetic fields created by a device known as a coil table.
But there are other strategies as well.
“Magnetic actuation has limitations,” says Mayer.
“The smaller you get, the less force you can exert. So my research looks at using a microtransmission, called twisted string actuation, to augment the output so we can have really small but impactful surgical tools.”
Mayer explains that this method traditionally works by connecting the tools to long cables. By twisting these strings with a rotational input, like a motor, the researchers can make the strings shorten in length with each turn. This creates a strong pulling force which, when miniaturized, is ideal for tight spaces like inside surgical forceps.
In conjunction with magnetic actuation, twisted string actuation can lead to forceful, wireless, and small surgical tools that are ideal for minimally invasive procedures in hard-to-reach places in the human body.
use Mayer’s twisted string actuation method to grip
and pull tissue. (Photo by Tyler Irving)
This research focus and Mayer’s collaboration with Dr. Shlomovitz would lead her to create a device for cancer removal along the gastrointestinal tract to help surgeons remove the disease endoscopically in one surgery instead of multiple, and Mayer filing a patent for her design.
“Gastrointestinal cancer accounts for one in three cancer deaths globally and is currently on the rise in North America and is starting to target a lot of young adults,” says Mayer.
“It’s not yet clear why it’s currently on the rise, so I’m getting to work on a tool that can help treat these early diagnosed cancers. It means a lot to me in terms of the future impact of my work.”
Mayer’s graduate journey wasn’t only about technical innovation. She also became a passionate advocate for youth outreach and equity in STEM, leading programming through the Robotics Leadership Program and speaking publicly about supporting women in science and engineering.
“I think it’s important to give back,” says Mayer.
“I was lucky to have a parent in engineering and be exposed to engineering through different community events, but not everyone has that opportunity. Outreach helps young people see what’s possible, so this was something that was easy for me to become passionate about.”
As she looks ahead, Mayer is exploring opportunities in research and development in medical device design and plans to continue working at the intersection of engineering and healthcare.
“I’m still figuring out what’s next,” says Mayer.
“But I know I want to keep designing tools that help people and keep inspiring others to see what’s possible with robotics.”
– This story was originally published on the University of Toronto’s Robotics Institute on November 19, 2025 by Amanda Hacio.