Eight students from The Haverford School's soft robotics club were awarded first place in the 2017 High School Soft Robotics Design Competition, sponsored by the Soft Robotics Toolkit at Harvard University, for its creation of edible soft robotic actuators. More than 90 teams around the world submitted designs for the 2017 competition, with the goal of advancing the field of soft robotics.
Actuators are the components of machines that are pneumatically controlled and responsible for their movement. The students developed the material for their actuators from gummy bears and also formulated a now-patented mix of corn syrup, gelatin, water, and flavoring. Because of the materials used, these edible pneumatic actuators are fully biocompatible, biodegradable, and "can inform the design of future implantable soft robotic devices," the eight students wrote in their winning submission.
Haverford's design is currently in the form of tasty, movable candy, but is also a "proof of concept for soft robots to be used in applications within the human body," the Soft Robotics Toolkit said in their announcement of the winners. Traditionally, silicone materials have been used to create soft robots, but silicone does not degrade in the human body.
Soft robots that are edible and biodegradable have far-reaching applications in the biomedical field because they can interface directly with cells to perform functions, such as delivering medicine or assisting the dynamic function of tissues and organs, said Holly Golecki, Upper School science teacher and the advisor of Haverford's robotics clubs.
Creating the actuators to make them both functional and taste good was a long process. First, the students analyzed commercial gummy bears, and then experimented with melting the gummy bears to design molded, inflated actuators.
After vigorous testing of these actuators, the students wanted to decrease production time and achieve more rigorous actuation. They decided to test different ratios of the four key ingredients – gelatin, corn syrup, water, and flavoring – in order to create their own optimized formulation for creating actuators.
Both kinds of actuators were then subject to mechanical compression testing to analyze stiffness, elasticity, tensile strength, and structural integrity. The students also designed a degradation study, putting the candy inside a saltwater solution, to simulate how robots made of this material would degrade in the human body over time. They ultimately created candy that could actuate eight times in succession, and still maintain its structural integrity.
"We worked really well as a team to document everything that we tried to do in research, design, and testing, but we all experienced the long, slow process it takes to create something like this, " said soft robotics club founding member and VI Former Matthew Baumholtz. "Our end product was created as a result of bouncing back from failure again and again."
"Since there are so many facets to the project, each student was able to specialize in an area they were most interested in," said Golecki. "This project incorporates so many aspects of science – they used technology like 3-D printing and CAD (computer aided design); built mechanical components; programmed electrical circuits; utilized polymer chemistry; studied the mechanics and biocompatibility of different materials; and then visualized and communicated all their data."
The students also see applicability for their robotic actuators in the education field.
"I think these soft robots have a huge ability to spark kids' interest in engineering, robotics, and science in general," said club member VI Former Cal Buonocore. "Teachers can take candy, an air pump, and one of our actuators to teach robotics – it's accessible even at the elementary school level."This was the first submission to the Soft Robotics Toolkit by Haverford's soft robotics club, but members plan to start a new project in January for submission to the Toolkit's design competition this summer.