Engineers from the San Diego University of California and the Harvard University announced in a paper published Thursday in the publication Science that they designed a 3-D printed robot made of a combination of hard and soft materials. The machines, described in the journal Science, could help engineers design more robust robots, ones that could be used in future rescue missions.
Advertisement
Thanks to the blending of the softer materials, these nature inspired machines which mimic functions of animals such as insect larvae or snakes, are a new generation of robots more resilient, safer, and more adaptable than their rigid counterparts.
The robot’s body transitions from soft to hard, reducing the stress where the rigid electronic components join the body and increasing the robot’s resiliency. “In nature, complexity has a very low cost,” Tolley said. “Using new manufacturing techniques like 3-D printing, we’re trying to translate this to robotics”, Tolley said.
Engineers explained that the combo between soft and hard in the robot’s bodywork is the secret that makes it such an efficient jumper.
Bartlett fabricated the robot on a Stratasys Connex 500 3D printer using two different materials “that were mixed at different ratios to form a 9-layer spectrum from completely rigid to completely soft”, he says.
So the scientists decided to build a faster robot with hard and soft elements – and they chose to make a jumping robot.
But what if you could combine the autonomy and speed of a rigid robot with the adaptability and resiliency of a soft robot, and do so relatively cheaply and quickly? They made a decision to go with the more flexible design. “This ability to fabricate unitary soft robots composed of gradient materials that emulate natural stiffness gradients of living structures paves the way for mass fabrication of robots that can integrate seamlessly with people, whether in our homes, at work or in operating rooms in the future”, said Donald Ingber, M.D., Ph.D., at Harvard’s Wyss Institute, according to a release.
To jump, the robot inflates one or more of its pneumatic legs to point the body in the direction it wants to move to, fills the body with a mixture of oxygen and butane, and then ignites itself. The robot is 3D printed using multiple materials with varying properties, ranging from very rigid to extremely flexible. When the chemical charge is exhausted, the bottom hemisphere goes back to its original shape.
In resilience tests, one bot performed more than 100 jumps without breaking, and another survived dozens of drops from a height of about 1 metre.
The two hemispheres surround a rigid core module that houses a custom circuit board, high-voltage power source, battery, miniature air compressor, butane fuel cell and other components. It’s a powerful jumper, reaching up to six times its body height in vertical leaps and half its body width in lateral jumps. He was hired at UC San Diego in fall 2014.
Advertisement
Previous work on these kinds of soft robots often had to use injection molds and other traditional manufacturing methods to make the parts – which can be costly and inefficient. He plans to further explore and expand the field of biologically inspired robotics in coming years.
