The SpiderHarp

By Gregg Kleiner

Sometimes, engineering and art collide in unexpected ways that give birth to new and interesting results.

Sometimes, the collision occurs in surprising places, like an Oregon State University research lab where mechanical engineers and roboticists are taking cues from spider webs.

And sometimes, serendipity plays a role. Like when a musician turned professor happens to hear about the spider-web research project on the BBC and then discovers that the project is happening practically next door. He wonders if it might be possible to create a new musical instrument and reaches out to the research team. 

Such a random collision of art and engineering unfolded at OSU over the past year or so. Not only did the results benefit the spider-web study, but it’s now possible to play music on an instrument designed like a spider web. 

The Early Stages

It all started as a National Science Foundation-funded research project led by Ross Hatton, an associate professor of mechanical engineering and robotics. Hatton and doctoral candidate Andrew Otto were trying to better understand how orb-weaver spiders, which have poor eyesight, rely on their eight legs to interpret the vibrations coming through the strands of their webs to identify and locate prey.

Chet Udell is a classically trained trombone player and was newly hired at OSU when he heard the BBC story about the spider web project. “I saw this news story about a big, orange, 4-foot spider web that researchers were using to study how spiders listened to the vibrations coming through their webs,” says Udell, an assistant professor of biological and ecological engineering whose Ph.D. work combined musical composition and electrical engineering. “I’m always looking for new technologies to make an instrument, so this big spider web immediately sparked my imagination.”

At the time, Udell didn’t realize that the spider-web model he had read about was located in a lab at the university where he had just started working. Udell and Hatton later met at a mixer for undergraduate research, where Hatton presented his work on spider webs. When Hatton told Udell he’d reserved the URL, Udell figured that was a good sign. He became, well, entangled in the project.

The Engineering

Hatton directs the Laboratory for Robotics and Applied Mechanics. His doctoral student Andrew Otto had been collaborating with researchers at the University of California, Berkeley, exploring how spiders use their feet to detect vibrations and determine what has landed in their web — whether it’s prey, a fallen leaf, a predator or a potential mate.

Ross Hatton, left, an associate professor of mechanical engineering, and graduate student Andrew Otto study how spiders detect and respond to disturbances on their webs. They foresee applications to widely spaced networks such as solar arrays in space. (Photo: Karl Maasdam)

“I’ve always been interested in the intersection of math, physics and biology,” Hatton says. “I’m trying to understand the fundamental principles that the animal is taking advantage of. It’s not biomimicry but looking at bio-inspiration in order to understand what’s happening.”

In the lab, Hatton and Otto had constructed the 4-foot diameter web using parachute cord (orange, of course, since they’re at Oregon State), zip ties, bungee cords, glue and an octagonal aluminum frame. All of it was outfitted with electronic sensors (to sense vibrations) and processors (to convert sensory data to location). To turn the data into outputs, they used algorithms, essentially a series of steps encoded in software, based on computer models of how real spiders rely on their webs and eight legs for an unusual form of communication.

The research team hopes their work on the bio-inspired network might lead to applications where structure is sparse, i.e., with open spaces and few connections, like the frame of a house. The technology could be used, for example, on a large solar array in space to quickly pinpoint damage caused by micrometeorites. Or to attach microphones to flooring in order to determine the level and flow of foot traffic and establish the best emergency evacuation routes.

“This technology could apply anywhere you’re using a sensor,” Hatton says. “What we’re doing is similar to earthquake monitoring systems, or systems that detect nuclear tests, which use sensors distributed around the world to determine signal shape and timing to pinpoint geographic location. But we’re looking at applications in string-based, very sparse structures, as opposed to structures on a surface with continuous connections. Our technology has lots of open space in the spider web, and that’s the big technical difference — that, and how we interpret the data.”

Enter the Musician

All of the research results were fine for science and engineering, which are focused on determining where on the web a disturbance was happening and how the information was transmitted to the mechanical spider squatting at the center of the artificial web.

When Udell wanted to use the web to generate musical tones, Otto and Hatton were enthusiastic, but the collaboration required the researchers to retool and make refinements. Ultimately, however, following the path inspired by an artistic application led to significant improvements in the research and technology.

Hatton loves music. He plays the piano and had played brass in his high school band. But Udell brought a deep wealth of music theory that he translated into engineering, so that Hatton and Otto could make the necessary adjustments. 

“Chet brought in music theory, music scales and musical effects like long and tremulous notes, how a steel drum sound is different from a skin drum and more,” says Hatton. “And then he took a computer synthesizer program and tailored that to match up with the physical interface that the model web gave him. And then he composed music!”

When Udell first saw the SpiderHarp up close, it was not what he was expecting, musically. When you plucked a string, an electronic arrow on a screen would point to the general vicinity of where the string had been plucked, and LED lights would indicate how loud the vibration was. But the distance detection wasn’t ideal for music. And the harp had a very slow response. 

“As a performer, you can’t have a quarter-second delay,” Udell says. “That’s okay for a spider, but not for a performer.”

So Udell worked closely with Otto to refine the SpiderHarp, weaving art into the engineering. “I would present him with all these problems, telling him it wasn’t fast enough, or not accurate enough, and why couldn’t I do this or that, and Andrew would go right to work on it,” Udell says. “And he delivered on all the weird demands I put on him. It really takes a special person to roll with that.”

Over time, what Udell refers to as “a frivolous act and creative outlet” ultimately optimized the algorithm to do more than what it had been doing. “It benefitted the original research, revealing a lot more about how spiders could be perceiving the world and expanding how the research could be used,” Udell says. “Response time went from a quarter of a second to one-tenth of a second, the distance was dialed in to exact strings, and amplitude became very accurate. I was very impressed.”

Headed to Carnegie Hall?

Last spring, the SpiderHarp was selected as one of only 15 finalists worldwide at the Guthman New Instrument Competition hosted by Georgia Tech’s School of Music. The OSU research team transported the harp across the continent so that Udell could play it for the first time in front of a large audience. The movement he composed and played at the competition was fittingly titled, Etude No. 1 for SpiderHarp.

Udell describes the sound of the SpiderHarp as “whimsical and enchanting, a blend of 20-something string instruments from around the world, each tone leading with a bright body and velvety finish.”

Although he doesn’t know where things will go from here, Udell would like to see a concerto for SpiderHarp in an orchestra, or have the instrument be scaled up in size.

“At one point in history, there was a first piano, which was probably met with incomprehension and considered a failure,” Udell says. “But that wasn’t the piano’s final form. It was an early, experimental form. So I can see there being instruments like the SpiderHarp in the future, but I would like to see it much bigger, so two people could play it by bouncing around on big steel cables to make music. They could emulate how spiders see. This is really the first musical spider web of its kind, so it would be nice to keep it going and see what happens.”

In July, Udell played the SpiderHarp for an enthusiastic audience at da Vinci Days, the annual arts and technology festival held in Corvallis. He also played another instrument that he invented, the Optron, ( which looks like a combination of light saber and electric guitar.

Following that performance, Udell met people from CymaSpace, an organization that uses technology, education and outreach to make arts and cultural events more accessible and inclusive to people who are deaf or hard of hearing. Udell has already launched a collaboration with CymaSpace to evolve the Optron toward an open source, multisensory instrument for engaging broader audiences with musical performance. 

The Power of Art and Engineering

Part of the reason combining art and engineering worked so well on the SpiderHarp project might be because both Hatton and Udell experienced a mixture of the arts and sciences during their formative years. Hatton’s father is a chemical engineering professor, while his mother teaches quilt making and is a published quilt author.

“That might explain the very geometric way I approach things,” says Hatton, who grew up playing with snakes and whose robotics research explores the physics of snake-like motions.

Udell’s father was career military and his mother a stay-at-home mom who had played saxophone in high school. The family moved often, and Udell remembers singing during long car trips. He started playing the trombone in middle school and also plays piano and guitar. He was averse to science and math, but when he took a class that used computers to make music, he was hooked.

“When I could create a line of code and hear what it sounded like and see what I could do creatively with it, I saw technology in a very different way. It suddenly wasn’t hard to overcome my aversion.”

Today, Udell enjoys looking at technology and applying it in artistic ways, as he’s doing with both the SpiderHarp and the Optron.

“When you do that, it reveals things about the technology you wouldn’t have considered and vice versa,” he says. “In the SpiderHarp, the music and the engineering coevolve, pushing the two disciplines in directions that neither may have explored on their own.” 

Improviser’s Collective Sparks Creative Partnerships

Imagine painting to the sound of waves, composing music in response to the breath of a forest, or dancing to the inspiration of robot technology. Like the SpiderHarp, these and other creative endeavors are emerging from efforts to connect people across disciplinary boundaries at Oregon State University. 

Combining the arts and humanities with science and engineering opens opportunities for students to learn and for the public to participate in discovery, says Dana Reason, composer and coordinator of contemporary music studies in the Department of Music. 

To spur cooperative activities among artists, musicians, engineers and scientists, Reason has created the Improviser’s Collective. She also wants to encourage more women to put their own marks on collaborations. “I’m trying to create more inclusive spaces for creative scholarship,” she says.

Reason’s effort adds to ongoing activities such as the Seminarium, a student-based creative initiative based in the Department of Microbiology in the College of Science and the School of Arts and Communication in the College of Liberal Arts.