KALONA

When I arrive at his home in rural Kalona, Benjamin Lothamer greets me with a firm handshake. He welcomes me and we head downstairs to his basement laboratory to talk about his latest projects.

Over the next hour, he’ll show me drawings and prototypes, hundreds of pages of research and documentation, a draft of a report he has written for publication, and a wall filled with awards.

Lothamer’s interests are mechanical engineering, prosthetics and orthotics, CAD, 3-D modeling, and robotics. Right now, he’s working on designing a prosthetic hand that improves upon previous models and could be a game-changer when it comes to access, utility, and quality of life for amputees. His thoughts are on case studies and licensing agreements.

All very normal stuff for a bioengineer.

Except Lothamer is a 15-year-old high school student.

The Hand Project

Currently a 10th grader at Mid-Prairie Homeschool dual enrolled at Kirkwood Community College, Lothamer started “the hand project,” as he calls it, at the end of 8th grade. That was the last year he attended Mid-Prairie as a traditional student – but we’ll come back to that.

“I think I first came up with the hand project in art class because I was just really bored and had nothing to do, so I drew that one day,” he says, indicating a shaded pencil drawing of a mechanical arm. “I was like, you know, this would actually be kind of fun to build.”

At that same time, he had been gaining confidence in his work with the Robotics club, which he joined the previous year. “I did my first home project” – a silicone ball filled with coffee grounds, which makes a perfect robotic gripper – “and that was when I first got the confidence to do projects at home,” he says.

When Lothamer’s aunt and uncle got a 3D printer, he saw its potential; soon he had his own Prusa printer set up in his bedroom, and he started printing finger protypes.

“It’s a really classic engineering challenge; everyone from Nicola Tesla to a lot of mechanical engineers have done some kind of a hand project at some point because it’s really difficult to replicate, because you have, obviously, three main joints, and then you have four or five different axes of motion with most of your fingers,” he says.

Then he points to a collection of 21 failed prototype fingers, mounted to a board. “This is my den of shame,” he laughs.

Down the Rabbit Hole

Lothamer’s hand project may have begun as an intellectual puzzle, pursued just to see if he could build such a thing, but it didn’t stay that way for long. Once he started delving into the design choices he would have to make – should the hand grip or clamp? Should it be gear-based or cable-based? Should it be muscle-driven or electric? – he realized he had to consider something more than what is possible or fun. He had to consider the end user.

He was no longer building a model or toy; he was building a prosthetic, a replacement limb that could be used in the real world. He had to move beyond raw mechanics; he had to learn what prosthetics were already on the market, their problems, and how they could be improved. He had to meet the people who were using them and understand their needs, challenges, and desires.

Lothamer compiled over 800 pages of research, found a mentor at the University of Iowa, and then went out into the real world.

His mentor, professor emeritus Donald Shurr, helped Lothamer make connections at the Univeristy of Northwestern Chicago, where he learned more about “the medical side of prosthetics,” and at a lab in Boulder, Colorado. He was introduced to Leroy Petry, a Medal of Honor winner and amputee who tests prosthetics for the military.

“Originally, this project wasn’t even going to be a prosthetic. It was just a hand that I was doing,” Lothamer says. “[Petry] was really one of the biggest inspirations in turning this project into a prosthetic hand instead of just a robotic hand.”

Considering real people – usually military or farmers, as upper limb loss primarily occurs due to trauma rather than disease, Lothamer says – led him into the field that forms the heart of prosthetics: psychology.

“That’s actually a huge, huge section of prosthetics,” he says. “It’s the psychology more than anything. There are more efficient designs than a human hand to grip things, but it’s going to make a huge impact on the patient’s psychology, and that’s why you don’t see a lot of non-humanoid hands on the market.”

Finding a Focus

When a creative individual wants to make a difference in a domain, they must find a problem to focus their psychic energy on and solve. For Lothamer, the first part hasn’t been difficult; he’s found a set of problems in the world of prosthetics in need of solutions. As we talk, a few critical ones rise to the surface: speed, access, and performance.

Speed

“Conventional prosthetics take a minimum of eight weeks for the patient to receive,” he explains, and that’s not a good thing. When a limb is lost, dystrophy occurs quickly: a patient’s “muscles kind of break down and lose function, and you actually also lose your neural pathways.”

The faster one gets a prosthetic, the better the outcome.

“There’s a big correlation between wait times for prosthetics and abandonment rates,” he explains. “Basically, you don’t want them to learn to live without their arm. In a way, it’s going to be better for their quality of life overall, and also have a lot of psychosocial benefits. Socially, there’s a huge benefit to using a prosthetic, and it’s also a huge thing for their contribution to society, or at least perceived contribution.”

3-D printing enables the process to be sped up; “this all can be manufactured in less than 24 hours,” he says.

Access

Access is another issue when it comes to prosthetics. The retail price for a conventional prosthetic hand is about $30,000 - $55,000, Lothamer says. The hand he created for his project cost him less than $350 to create, which indicates the potential 3-D printing has to lower the cost of a prosthetic.

He has ideas for commercial applications.

His design could be used as “a training piece for the patient to use after their surgery until they receive their commercial prosthetic, and that will allow them to keep those neural pathways strong and actually learn how to fire those muscles independently.”

Or “this could be used as a permanent design, and that’s a big goal of the next year’s research, making it a lot more durable and a lot easier for someone to build themselves,” he says.

If one could build their own prosthetic, even single-handed, it would be that much more accessible – and have the advantage of also being repairable by the owner as well.

The commercial side is something Lothamer is working on now.

“I’m actually going to be licensing this to hospital systems,” he says. “I’ll sell them the license, and then they can produce it for their patients and charge them. There’s a maximum amount that they would be allowed to charge for that.”

Performance

Most of us have never considered if our hands are the optimum tool; we simply go about our lives, adapting as needed with rubber grippers for opening jars, silicone fingers for turning pages, and “third hands” for holding materials in the workshop.

Lothamer has given it consideration, and the human hand comes up short.

“Really my biggest goal is to eventually get this as good or better than a regular hand. It’s going to take years and years of work, but I think that’s really the end goal of this,” Lothamer says of his prosthetic hand model.

Once he committed himself to the hand project, he came to understand what he didn’t want: a hand that could only assist, never acting as the “task hand;” a hand that could only clamp, not actually grip objects; a hand that required a great deal of the user’s effort to use, rather than one that was intuitive and responsive.

So he set himself that task, to make the best hand possible. He’s concluded that the best hand may be one that evolution hasn’t provided us with yet. The best hand is one he’ll have to design.

A Winning Design

Over the 2023-24 school year, Lothamer’s hand project took him to the Eastern Iowa Science and Engineering Fair, where his design earned him Senior Champion. He moved on to the State Science and Engineering Fair of Iowa, where he won first place in the Engineering category and was Reserve Champion. He finished his season at the 2024 International Science and Engineering Fair in Los Angeles, where his project won third place in the Biomechanical Engineering category.

There is no question: his work has placed him at the top in his field.

And he is still a high school student.

And Now, Back to High School

I asked him if he was always exceptional among his peers.

“Believe it or not, in fifth grade I was about four years behind in reading, and probably a year and a half behind in math,” he says. “I think COVID helped me a lot in getting a work ethic and deciding that I really like to do this type of stuff.

“By the time we were back in school after COVID, I’d really grown to like studying by myself and learning as much as I could, which eventually led me to switching to the Mid-Prairie Homeschool. It’s just up here up the road, and they gave me the opportunity to pursue something like this by not having so much time spent in school.

“My parents were definitely really big in allowing me to make that change,” he explains.

“I don’t think it’s a natural thing so much, I think it’s finding something that you’re interested in and then pursuing it,” he says of the qualities that make him exceptional.

Homeschool allows him to “condense a lot of that education to work with my schedule a lot better,” but he’s still involved in regular high school activities, such as running cross country and participating in the Robotics club.

He doesn’t see himself as terrifically different from his peers; if anything, the only thing that separates them is a fixed versus growth mindset.

“The only thing that really bothers me is when people think they can’t do something, or they’re just not smart enough, or ‘I’m not a good test taker,’” he says. “Like I said, I used to be below average. I think it’s really just working as hard as you can at something.”

Looking Beyond

As he looks ahead, Lothamer has a few ideas for how he might proceed after concurrently earning his high school diploma and Bachelor of Science degree. Perhaps he’ll attend graduate school, perhaps the Air Force Academy; perhaps he’ll become an entrepreneur, perhaps he’ll teach; perhaps he’ll retire early, perhaps he’ll work as a missionary.

“I’m 15, so it’s kind of hard to plan that far,” he says.

But there is one thing of which he is certain: his hand project has a future.

“I definitely want to license this out and get it to as many people as possible, because it has a huge opportunity to really improve the lives of several hundred thousand people across the world, which is a very large number, more people than are anywhere around Kalona,” he says.

He also, in spite of having “a lot of hobbies, a ridiculous number, honestly,” feels confident that he has chosen the right professional field for himself, one that feels meaningful.

“It’s a very rewarding type of engineering,” he continues. “In Biomedical Engineering, you get to see that direct impact to an individual patient, and you can see how it directly benefits their quality of life, which I really like.”

And to what does he credit his success as a biomechanical engineer so far?

“I think just being creative and being willing to learn and continue to benefit others,” he says.

“And also having major OCD,” he chuckles. “That helps.”