Nicholas Witham, a fifth-year biomedical engineering Ph.D. student at the U, won first place in the Wilkes Student Innovation Prize competition in May 2023 for his proposal titled, “Renewable Energy And Carbon Capture With Thermomotive Biopolymer Textiles.” His idea proposes a novel renewable energy system that generates power through the daily heating and nightly cooling of the earth, known as the diurnal temperature variation. This can be accomplished using a type of artificial muscle known as a twisted coiled polymer actuator, which can be designed to either contract or expand when heated.
For this episode we are sharing an interview Nick Witham did with Chis Nelson on the U Rising Podcast, in which he describes his winning idea as well as his efforts to create prosthetic limbs that affordable and accessible.
Listen to the Interview
Chris Nelson: Welcome to U Rising, where we share stories about research, innovations and key initiatives taking place at the University of Utah.
I’m Chris Nelson, host of this episode and chief university relations officer. I’m excited to have Nicholas Witham as my guest today to talk about receiving first place in the Wilkes Student Innovation Prize competition awarded by the U’s Wilkes Center for Climate Science and Policy in May.
Nick is a fifth-year biomedical engineering Ph.D. student at the U. His focus is the intersection of mechatronics, electrical instrumentation and material science. In practice, that means he’s researching and developing high-performance sensors and actuators for assisted devices that are intuitive, affordable and accessible.
Nick has applied textile engineering methods to improve operations of both prosthetic limbs and renewable energy generators, which we’ll hear more about in this episode.
Welcome to U Rising, Nick.
Nick Witham: Thank you.
Chris Nelson: That’s a lot of words I haven’t said in a long time, so that’s quite an introduction! But let’s talk with your background. Your bachelor’s degree is from the University of North Carolina. Talk about that experience and then what brought you to Utah to pursue your master and doctoral degrees?
Nick Witham: Yeah, I went to the University of North Carolina at Chapel Hill. I studied biomedical engineering there. I didn’t quite know exactly what I wanted to do until I started with this club-slash-nonprofit that 3-D printed hands for kids with limb differences—so born with different limbs. So they need prosthetics and they’re not covered by insurance.
And while I was working on that and trying to make those hands better, I found out that I, one, was really good at it and, two, really liked it. So I started doing research in labs there. They told me that if I wanted to pursue neuroprosthetics, which turns out I have a lot of interest in but no skill for, to come to the University of Utah. So, I applied and, yeah, sort of fell into it.
Chris Nelson: Excellent. Had you heard much about Utah before you came out here or was that just kind of a gamble you took?
Nick Witham: Not at all. So, yes, my old boss, my old Pi, Helen Wong, she suggested that I apply, but I said no, there’s no reason. My parents convinced me to do it. I’d already applied to all these other colleges. And there it was, right in the middle of finals, I got accepted and they had this recruitment weekend where you would go skiing. So skipping finals and going skiing, it was a pretty easy decision. And I came out and I was more than happy with everything out here. Yeah, it was just a beautiful place and great facilities.
Chris Nelson: I know Utah’s got a reputation, the university, around the Luke Arm, as we call it, and a lot of the prosthetic work going on here. Did that play a role in your decision to come out here?
Nick Witham: Yeah, absolutely. I think it’s crazy the work that Jake George and Greg Clark have accomplished, making prosthetics feel for amputees. It’s incredible. I mean, if you lost a hand, that’d be something that you’d expect in this day-and-age, you know. And in terms of prosthetics, just being able to accomplish something so groundbreaking is inspiring.
There’s also a lot of osseointegration work, so that’s like making prosthetics part of your actual arm. It’s part of your bone. Incredible. And you may not know this, but the world’s largest producer of prosthetics has its American headquarters right here in the Salt Lake area, Ottobock.
Chris Nelson: And one of the challenges with the current technologies is it’s just not being used by folks. And so using this technology just to make the products better.
Nick Witham: So the way I relate it to people is, well, in my own personal journey, I discovered when I was working with those kids, 3-D printing hands, we’d be literally giving them to them for free, cutting edge stuff, and they wouldn’t be used.
And it turns out this problem goes all the way to the top. So advanced prosthetics that cost as much as a Tesla Model Y, 50% of the time they just end up collecting dust on a shelf for a myriad of reasons. And I always say that’s like the population of Salt Lake City each owning a Tesla that they never use. That’s wild, you know, that’s a big problem.
Chris Nelson: So, let’s get to your project. So you pitched your climate solutions idea at the inaugural summit hosted by the Wilkes Climate Center for Climate Science and Policy and received the top $20,000 prize. So congratulations. Tell us about your idea, which is titled, and I quote, “Renewable Energy and Carbon Capture with Thermomotive Biopolymer Textiles.” Now, we may have lost some of our audience as I read that, but break that down for us.
Nick Witham: Well, first off, I was always told make those titles as long and complicated as possible. Basically I research artificial muscles made out of fishing line. When you heat them up, they contract and exert a force. And the great thing is, is that every day the Earth heats up and cools down, which would make them contract and we could then use that contraction to spin a generator.
And, it was one late night in the lab and I decided, you know, maybe these numbers make sense, maybe this could be less expensive than solar. So I started cranking the numbers out, talked to my boss and here we are.
Chris Nelson: Was that based on the award that you saw from the climate science or did that come after? What prompted you thinking that thought even?
Nick Witham: So, a lot of what I do has to do with the performance characteristics of these artificial muscles. So we are concerned with their efficiency, their power to mass ratio, which is also called specific work. You don’t need to know any of this, but we look at their viability as a new tool, as a new technology for prosthetics, you know, we have to assess user needs in biomedical engineering. So it all seemed to click pretty instantly, yeah.
Chris Nelson: Interesting. I learned a new word, biomimetics. Explain that to us.
Nick Witham: Biomimetics is the attempt of engineers to mimic biology. So it encompasses a large number of things. To me, making my artificial muscles biomimetic means making them pull with the right force over their area and making them contract the right amount so they can actually mimic human muscle.
Chris Nelson: Let me ask it this way. So again, you’re working with prosthetic limbs and exoskeletons in your research and you just saw that connection back to climate. That’s just so interesting to me. It’s into the mind of our Ph.D. students a little bit.
Nick Witham: So, you know, I’m making a tool, I’m making a technology, and, you know, as an engineer you get curious and I think following your creativity is just something you always have to do in any field. So when I have an idea and it’s crazy, I want to see how crazy it actually is and this one shocked me that it wasn’t.
Chris Nelson: Nice. So talk about this approach. So it’s better than, it’s comparable, it’s better than existing renewable energy sources like solar and wind?
Nick Witham: Well, right now it’s still a concept except for the performance characteristics of these artificial muscles. Those are already published, and our manufacturing method was published yesterday, actually, in a textile research journal.
So I see a lot of potential benefits. So compared to solar, there’s no e-waste with these. So, the system is entirely recyclable.
Another advantage is that you can combine it with existing renewable energy generation units. So, let’s say you have a solar field or a wind turbine field, you could put these in that same field and use the same cables and infrastructure on this to decrease the total price of the energy coming out.
Another benefit is lower maintenance than wind and solar. Turbines are meant to spin very fast. There’s no external moving parts, unlike solar. You put it in the desert and, yes, it gets covered in sand and, yes, it gets scratched by that dust, but you don’t have to replace these panels. It’s just a big black box in the middle of the desert.
And lastly, I’d like to mention that you can make these actuators with bio-derived plastics so you can turn corn husks into this and that becomes an indirect form of carbon capture. So, the way that chemistry works is that carbon molecule CO2, it accounts for most of the mass, like 68% or something like that. And most of the mass of our polymer is also carbon. So, it works out that you can store three kilograms of CO2 and one kilogram of our polymer, which means that it becomes more and more cost-effective than other carbon-capture technologies and can even turn a profit at a certain point.
Chris Nelson: And you may have mentioned this, but where are you at in development? This is still kind of theoretical. Do you have some prototypes? Where are we at?
Nick Witham: Yeah. Well, I have plenty of prototypes of my muscles and we test them in these environmental conditions every day between 20 Celsius, room temperature, and 60 Celsius. So that’s my typical range I test and we’re working to make them more energy efficient all the time. In terms of the core technology and being able to make an actuator perform with the right characteristics, we’re on it. In terms of putting a unit in the Moab desert, that’s still like a year out.
Chris Nelson: For someone listening to this who doesn’t have a bioengineering background, kind of break down how this technology works.
Nick Witham: The goal for an energy generation unit is to make AC power. So the turbines have to spin at a certain speed to make the right frequency of that AC power. The way wind turbines account for that is in one of two ways. The first way is by turning it into a DC power, then back into AC. But that’s largely inefficient. You lose like 30% of your power doing that.
The other way is with this fancy technology called a doubly-fed induction generator. What the heck is that? I don’t even know. But what it does is it allows you to have a variable speed of rotation of your generator producing that same AC frequency and it’s more efficient. So we’re stealing different technologies from existing renewable energies to support this. So in fact, our generator is a wind turbine generator. That’s what we selected for this. Then it’s just about figuring out how long of an artificial muscle to make so it can pull at the right rate for that temperature change, which is called the rate of diurnal temperature change. It’s a big word, but it just means how much does the planet heat up in a day.
Chris Nelson: So I think of the wind turbine as those giant ones I find when I’m driving through Southern Utah. So, are we talking that size, the generator part of that?
Nick Witham: Yeah. So there’s smaller wind turbines, there’s personal use ones. So that’s what we were thinking for our initial unit, and they’re really actually quite fun. You can just find one on Alibaba or something. Yeah, it’s more accessible.
Chris Nelson: Gotcha. And a dumb question, but do they need to be in a particular place? Do they work better in certain places other than other places?
Nick Witham: Yeah, so the thing about diurnal temperature change is it is larger in higher altitude places that are very arid. So Utah’s a great candidate. Arizona’s a great candidate. In fact, I ran the numbers to figure out the portion of the U.S. that this is applicable for and it’s something like 68% of the land area. But since California has so many people, and Texas has so many people in it, it really accounts for like 75% of the U.S. population.
Chris Nelson: So down the road, I think of the solar panel farms, I think of the wind turbine farms. Is this a similar concept, I would come across a field with some of these things?
Nick Witham: I think it would look a lot more like a shipyard because these would very likely be in shipping containers. Our potential unit weighs less than one of those, maximally, so you could still ship them with existing transportation methods.
Chris Nelson: And I’m really trying to get my brain around the artificial muscle. It’s a twisted coiled polymer actuator. So twisted coiled polymer actuator. Describe that for a listening audience. What does that look like?
Nick Witham: It looks like a piece of string that has been coiled, which is kind of boring. And the way it works is . . .
Chris Nelson: Artificial muscle is much more interesting!
Nick Witham: Yeah. And the term is very buzzy, you know. Do most artificial muscles actually work like muscles? No. Most don’t even actually contract. I’d call them springs, but . . .
Chris Nelson: Gotcha, okay, good point.
Nick Witham: Yeah. The way that these work is the fact that it’s a twisted polymer, so if you just have a twisted polymer fiber and it has certain characteristics, it wants to untwist when you heat it up, and this is true of nylon fishing line, linear low density polyethylene, many, many materials.
But when you coil that, it makes it want to contract. And that puzzled a lot of us for half a decade. And we have a running theory that it’s basically like a helical spring, but in reverse. So when you stretch a spring, it actually manifests a torque on either end. And I think I have a little cat toy in my backpack to show this to people because nobody believes you. But let’s say, you know, that spring manifested its own torque, then it would contract. It’s just a spring but backwards.
Chris Nelson: Alright, so Nick, you mentioned the cat toy to kind of illustrate how these artificial muscles work. I do want to ask you to get the cat toy out and just walk me through that.
So, you’ve put this toy on the table behind us. To me it, it’s blue. It looks like a spring. It’s about three or four inches.
Nick Witham: Yeah, it’s a blue spring. You got it right.
Chris Nelson: I’m very observant.
Nick Witham: Yeah, if you stretch it, I want you to clamp down on the ends.
Chris Nelson: Okay. I’m clamping down on the ends.
Nick Witham: You feel that? So other than a force coming between your fingers, do you feel it like wanting to twist?
Chris Nelson: Oh, interesting. Yeah. It kind of reminds me when you play with a slinky a little bit.
Nick Witham: Yeah. It’s twisting in your hands, right? Well, just imagine that the material itself wants to do that twisting, it’d move in the same way.
Chris Nelson: Gotcha.
Nick Witham: So, it’s a spring in reverse.
Chris Nelson: Excellent. And that’s generating energy and . . .
Nick Witham: Yeah. Yeah. So, there’s torsional energy, so the thermal energy turns into torsional energy. Torsional energy turns into tensile, and then moving a mass is the energy output.
Chris Nelson: Interesting, interesting. So you’ve launched a new startup company, Gaia Technologies you’ve already received from recognition. Tell us about this venture.
Nick Witham: Yeah, so Gaia Technologies is something I’ve been working on for quite a few years now. Our goal is to restore function with innovation. Our flagship product is a biosensor array. What’s that? It’s a sensor that measures biology and this array, these sensors, they measure how a muscle gets fatter when it contracts. And our signal seems to be much lower noise, more directly in line with the length of the muscle, which is important for positional control of prosthetics. And from those two, we think we can get force. That said, we are venturing into new things outside of prosthetics and outside of just sensors. Our newest invention that we’re working on, we call it a pseudo-telepathy headset.
Chris Nelson: Okay, explain that.
Nick Witham: Yeah, so it’s a buzzword technology because we want to get traction, but it’s based on some pretty solid science. So when you think of saying a word, you can even feel it in your neck, your throat still twitches when you’re thinking of saying a word. You can probably feel this best if you think about yelling really loudly. Well, our sensors are very, very accurate and very precise. So they can measure that twitch. And then it’s just a matter of using AI technology to stitch them together.
So our approach is to decode individual sounds into the components of words, which are known as phonemes, and the prospadic information, which is the space between words, it’s the enunciation, it’s how you tell a joke, you know, and the volume. So we are designing this headset for people that are able-bodied and for people who have dysarthria, which is a weakness of their vocal chords, so think Stephen Hawking, so they can speak real time in their chosen voice without having to utter a word.
Chris Nelson: Interesting. So the voice would be artificially generated, but it would almost be . . .
Nick Witham: So you can voice bank. Voice banking is an existing technology that people use for progressive disorders such as ALS and MS. So probably not paralysis, depends on the type, but, you know, an average person could do that pretty easily.
Chris Nelson: So back to the Wilkes Prize, the $20,000. So will that help do stuff in the company or is that a separate project through the lab?
Nick Witham: Yeah, so the way that $20,000 is being spent is I’m buying a ring for my girlfriend. Yeah, that was the first thing, you know, I got my priorities. But, of course, we’re going to roll it into all these different projects and get them up and going, but it’s not quite enough to pay anybody a paycheck.
Chris Nelson: So, is she a fiancé yet or . . .
Nick Witham: No, I still have to go home for the family diamond.
Chris Nelson: Is she a scientist?
Nick Witham: No, she’s a social worker. She works at the Children’s Center.
Chris Nelson: Wonderful. So take me back into the lab, though. So I think one of the audiences I know we’ve got are folks who are just trying to figure out what happens at the University of Utah. So we talk about all the things that go on up here. As a Ph.D. student in a biomedical engineering lab, what does your day look like? I think a lot of people think of, you know, I’m in class, granted, I’m in the lab, but just walk us through that. If you were talking to a 16- or 17-year-old version of you, how would you articulate what’s to come?
Nick Witham: Well, it changes over time. It’s a very dynamic position. So my first few years here, they were spent doing courses just like my undergrad, but they were far less relevant than I wanted them to be, but I had more choice to pick, so, it was like, what am I doing wrong? But I feel like everybody has that sort of thing. You’re trying to pursue something and it’s ephemeral and you don’t know what it is.
And I was doing a lot of literature reviews. I was reading a lot of papers and I was trying to reproduce them, and I was contacting those authors and I was talking to my boss a lot about my theories and what I wanted to accomplish with my Ph.D. What three papers do you want to write? That’s typically how it’s phrased here at the U of U is you have to write three papers and each of those three papers have three separate experiments, three figures that you show, so what nine experiments do you want to do and what impact do you want to have?
But recently, post-Covid, post having all the equipment and all the experiments done, most of my time is spent working with my undergrads to get them up to snuff, new grad students to set the expectations and help them along and to actually write the papers and do the data analysis and all the programming stuff. So actually applying what you learn is the second half of your Ph.D. And it’s some of the hardest part, you know, because it’s always different. There’s no Ph.D that’s alike.
Chris Nelson: And somehow in all that you still found time to apply this to a climate solution, which is just really impressive.
Nick Witham: Yeah, you’ve got to follow your creativity to stay motivated. I think a lot of people lose sight of that.
Chris Nelson: So you’re a fifth year Ph.D. student. When are you going to graduate and what’s next? Do you stay in Utah? Are you going to go back to North Carolina?
Nick Witham: Yeah, I’m planning to graduate within the next six months. It’s not entirely my own decision. I have a committee of people that give me the degree or don’t, but afterwards I’m planning to continue my postdoc and all the things are lined up for that. So the postdoc is like a Ph.D., but you’re just doing more work but not a professor. It’s somewhere in between. And to have my company take off has always been a dream. So we’ll see how that goes.
Chris Nelson: Wonderful. Tell me about the company a little more. How many people have you got working there?
Nick Witham: Yeah, so legally I would call none of us employees.
Chris Nelson: Sure, yeah, caveat there.
Nick Witham: We aren’t paid. Everybody’s a volunteer, but that doesn’t mean that we don’t reward people with equity and we don’t have value as a company. So we had three main founders and tons of people that have come through and left. You know, the process of launching a company is one of those things I always wanted to learn and there’s no better way to learn than doing. And at U of U is, what, top five in the nation in entrepreneurship, and I’ve absolutely saw that I had to take advantage of that learning opportunity.
Chris Nelson: So yeah, we’ve talked to other entrepreneurs, but really your research innovation came first and you kind of got that entrepreneurial bug to make it more practical?
Nick Witham: Yeah, that came from all my professors and mentors over the years. They kept saying over and over, because I’m an engineer, if you want to have an impact, you have to make something that’ll sell because, you know, we live in a capitalist society and people won’t get it otherwise. So, you have to consider all the economic and business factors and I really took that to heart.
Chris Nelson: Nice. Well, Nick, thank you again for being on U Rising. Congratulations on your success and I’m looking forward to seeing what’s coming next out of your lab and your company.
So listeners, that’s it for today’s episode of U Rising. Our executive producer is Brooke Adams and our technical producer is Robert Nelson. As a reminder, you can find you rising on all streaming platforms.