A team of researchers from the University of Maryland has 3D-printed a soft robotic arm that is agile enough to play Nintendo’s Super Mario Bros. skill – and win!
The feat featured on the front cover of the latest issue Science is advancing, shows a promising innovation in the field of soft robotics, focusing on the creation of new types of flexible, inflatable robots for use in water or air instead of electricity. The inherent safety and adaptability of soft robots have aroused interest in their use in, for example, prostheses and biomedical devices. Unfortunately, controlling the fluids that make these soft robots bend and move has been particularly difficult – until now.
A key breakthrough in the group, led by Ryan D.Sochol, an assistant professor of mechanical engineering at the University of Maryland, was the ability to 3D-print fully assembled soft robots with integrated fluid circuits in one step.
“In the past, soft robotic hand fingers usually need their own line of control, which can limit portability and utility,” says first author Joshua Hubbard, who conducted the research as a basic researcher at Bioinspired Advanced Manufacturing in Sochol. (BAM) laboratory at UMD. “But by 3D printing with our soft robot hand integrated fluid transistors, it can play Nintendo on just one pressure supply.”
As a presentation, the team designed an integrated fluid circuit that allowed the hand to operate in response to the intensity of a single control pressure. For example, using low pressure only caused the first finger to press the Nintendo controller to get Mario to walk, while high pressure led Mario to jump. Controlled by a set program that independently shuts off low, medium, and high pressure, the robot hand was able to press the controller buttons to successfully complete the first level of Super Mario Bros. in less than 90 seconds.
“Recently, several groups have tried to utilize fluid circuits to increase the autonomy of soft robots,” said a recent doctor. researcher and co-author of the study, Ruben Acevedo, “but methods for building and integrating these fluid circuits with robots can take days to weeks with high manual work and technical skills.”
To overcome these hurdles, the team turned to “PolyJet 3D Printing,” which is like using a color printer, but with multi-layered multi-material “inks” stacked on top of each other in 3D.
“Within a day and with little work, researchers can now move from the 3D printer startup process to complete soft robots – including all soft actuators, fluid circuit elements and chassis features – ready for use,” said Kristen Edwards, co-author of the study.
The choice reinforces its strategy by winning the first level of Super Mario Bros. in real time was motivated by science as much as having fun. Because the timing and level of the video game is well established and only one mistake can lead to an immediate end to the game, playing Mario offered a new way to evaluate the performance of a soft robot in a uniquely challenging way that isn’t usually handled on the field.
In addition to the robot hand playing Nintendo, the Sochol team also announced in their paper soft robots inspired by the turtle. Terapin happens to be the official mascot of UMD, and all of the team’s soft robots were printed at UMD’s Terrapin Works 3D printing center.
Another important benefit of the team’s strategy is that it is open source, and the paper has read access open to all, as well as a link to additional materials on GitHub with all the electronic design files for their work.
“We share all of our design files freely so that anyone can easily download, edit as needed, and print 3D – either through their own printer or through a printing service like ours – all the soft robots and fluid circuit elements of our work,” Sochol said. “We hope that this open source 3D printing strategy will expand the availability, deployment, reproducibility and deployment of soft robots with integrated fluid circuits, and in turn accelerate progress in the industry.”
The team is currently researching the use of its technology in biomedical applications, including rehabilitation equipment, surgical tools and customizable prostheses. As a subsidiary of Fischell’s Department of Biotechnology faculty and a member of the Maryland Robotics Center and the Robert E. Fischell Institute of Biomedical Devices, the team has an exceptional environment to continue advancing its strategy to meet the urgent challenges of the biomedical fields.