A triple threat in mechanical engineering: Riggs siblings building their futures together

From left: Luke, Isabella and Matthew Riggs. Photo by Angela Foster.

For many college freshmen, finding a study group can be a challenge. But for triplets Isabella, Luke and Matthew Riggs, their study partners have been the same since birth.

The University of Tennessee at Chattanooga mechanical engineering majors are inseparable—attending every class together, taking the same coursework and earning identical 4.0 GPAs.

Their presence in the classroom hasn’t gone unnoticed by their professors—who marvel at their academic excellence, discipline and the rare dynamic of having three high-achieving siblings excelling in the same rigorous field.

“These three, I mean, they take classes together, they sit side by side, front row together,” said Dr. James C. Newman, professor and head of UTC’s Department of Mechanical Engineering. “Everywhere you go, you see them together. They are close-knit.”

Newman, who has the three in his Introduction to Engineering Computations course, has had many talented students walk through his doors over the years—but said he has never seen anything quite like the Riggs siblings.

“I don’t think I’ve ever had students like this before, to be completely honest. And there’s three of them,” said Newman—who came to UTC in 2011 after spending 14 years in Mississippi State University’s aerospace engineering program. “They’re engaged, they’re eager, they’re hardworking.

“To be completely honest with you, they inspire me and motivate me as a faculty member.”

The Riggs triplets—Luke (left), Isabella and Matthew—work in Dr. Reetesh Ranjan’s fluid mechanics laboratory in the Engineering and Computer Science building.

Isabella, Luke and Matthew grew up in a household that nurtured curiosity. Their father, Eric, is a mechanical engineer. Their mother, Rebecca, is a chemist.

The triplets, who also have an older brother, quickly found that they thrive in a structured, problem-solving environment.

“We all work together to ensure that everyone understands everything,” Isabella said. “Our parents placed a whiteboard up for us. All three of us can complete our homework and study for quizzes and tests by doing plenty of practice problems on the whiteboard.”

After one year at East Hamilton High School in Ooltewah, Tennessee, they enrolled at Collegiate High—a dual-enrollment program at Chattanooga State Community College. They spent eight total semesters in that program—including two summers—and earned their high school diplomas and associate degrees in May 2024.

Isabella said they pursued mechanical engineering at Collegiate High because it “allowed us to get most of the gen eds out of the way as well as calculus, linear algebra, statics and dynamics courses.”

The triplets became the first mechanical engineering cohort to go through the Collegiate High program.

“It was thrilling to say that you could do it,” Luke said. “Nobody else had done it in the 20-year history of the school being open. Being able to say you’re the first to do something is always a good feeling.”

They arrived at UTC last fall as 18-year-olds with 98 credit hours already completed—although they consider themselves freshmen on paths to receive bachelor’s degrees in 2027—and that head start propelled them straight into junior-level engineering courses.

Not only did they handle the transition, but they excelled.

Dr. Cecelia Wigal, UC Foundation professor and associate dean of undergraduate programs in UTC’s College of Engineering and Computer Science, has the Riggs triplets for Introduction to Engineering Design.

“They’re very good, strong students,” Wigal said. “Not just strong in terms of performance, but they have a desire to learn. They want to do things, they want to take in the information and they want to do well.”

When she first saw their names listed together on her class roster, Wigal wasn’t sure if they were siblings or simply shared a common last name. It wasn’t until introductions that she learned they were triplets.

“I’m learning just because they’re triplets doesn’t mean they’re exactly the same,” said Wigal, a member of the UTC faculty since 1999. “They come with their personalities and they’re their own people in how they relate. They’re individuals, but they’re all go-getters.”

“We all work together to ensure that everyone understands everything,” Isabella Riggs said of her brothers Matthew (left) and Luke.

As triplets, their closeness extends far beyond the classroom.

They live at home, commute together, and even work together as tutors and test proctors in ChattState’s Math Center—where they help students in subjects ranging from algebra to differential equations.

Studying together is second nature to them, something that’s been part of their daily routine for as long as they can remember.

They each have distinct academic strengths—Luke in thermodynamics, Isabella in computations and Matthew in engineering structures—allowing them to help each other in different subjects.

“When we study, we play to each other’s strengths,” Isabella explained. “If one of us is struggling with a concept, the others step in and explain it in a way that makes sense.”

“Like Isabella said, if I’m struggling with fluids or computations, I can go to her or Luke and vice versa,” Matthew said. “We help each other out and we study together a lot—especially when it comes to quizzes and exams.”

Isabella said it’s incredibly valuable to have that built-in support system, likening their teamwork to a poker game.

“We know each other’s strengths and weaknesses and we play them to our advantage,” she said. “It makes us stronger as students.”

Despite their shared path, each triplet has a unique vision for the future.

Isabella, the oldest and the leader of the three—according to her brothers—has a keen interest in biomedical engineering. She recently connected with Assistant Professor Hamdy Ibrahim about research opportunities.

“My interest is in computational medicine or improving current medical equipment and drug delivery systems to improve patient outcomes,” she said. “That is very interesting to me and that’s what I would like to do.”

Luke, born second, is drawn to thermodynamics and fluid dynamics. He said he’s fascinated by the mechanics of HVAC systems, heat pumps and steam power plants.

“I took Thermo-1 last semester and absolutely loved it,” he said. “It’s complex, but it’s so interesting to see how everything fits together. I want to do research in that field and see where it takes me.”

Lego bricks, he said, played a role in identifying “how everything fits together.”

“I played with Legos when I was a kid and loved to build stuff,” he explained. “As I got closer to the University, I looked into different fields and engineering lined up with my interest—and as I got more involved in my classes, it became more evident that the thermal sciences were more appealing just because of how interesting yet complex they could be.”

Matthew, the youngest and the most laid back, envisions staying in academia longer than his siblings.

He plans to pursue a Ph.D. in computational engineering and hopes to take part in UTC’s JUMP Program—which allows students to transition from their bachelor’s degree directly into a master’s program.

“I want to keep going,” Matthew said. “I’ve always been interested in how things work and designing objects or devices that would help people. Mechanical engineering best suits that.

“I like building stuff and designing stuff and engineering allows you to do that—whether it’s aerospace, mechanical, chemical. But I’m more interested in gears and structures and I knew mechanical was the best one for that.”

While they may have different specialties, they acknowledge that their fields naturally intersect.

“I think at some point our roads are going to branch out,” Matthew said. “We’ll each go our own way, but they might cross over.”

Isabella nodded in agreement.

“They might cross over, for example, with the artificial heart that uses fluid flow and thermodynamics,” she pointed out. “That could be one area that biomedical and computational would come together.”

Their mother, Rebecca, couldn’t be prouder of their successes.

“They have worked very hard to accomplish what they have,” she said. “It is phenomenal to say, ‘My children graduated high school with an Associate of Science in Mechanical Engineering—and they were the first to do so.

“They work hard, but more importantly, they’re good people. It’s very satisfying to see how well they’ve done.”

She also takes great pride in watching her triplets build their futures together.

“When you have children, you never know what they’re going to be like. You don’t know how they’re going to turn out. You don’t even know if they’re going to get along,” Rebecca said. “It’s very comforting to know that the three of them enjoy each other.

“Yes, they’re thrust upon each other because they’re the same age, but they have the same interests and they enjoy each other’s company.”