New 3D-printed cube robots, which have shock-absorbing skins and are precise in their movements, have been created by MIT scientists. This invention is an advance that may pave the way for more durable drones and smartphones. Researchers developed the Programmable Viscoelastic Material (PVM) technique that allows users to program every single part of a 3D-printed object to the exact levels of stiffness and elasticity they want, depending on the task they need for it. The scientists 3D printed a cube robot that moves by bouncing, and outfitted it with shock-absorbing “skins” that use only 1/250 the amount of energy it transfers to the ground. Also Read - National Science Day: Top 5 AR apps available on Apple's App Store to learn scienceAlso Read - Facebook for Android will soon get dark mode and coronavirus tracking feature
“That reduction makes all the difference for preventing a rotor from breaking off of a drone or a sensor from cracking when it hits the floor,” said Daniela Rus, director of MIT Computer Science and Artificial Intelligence Laboratory in the US. “These materials allow us to 3D print robots with visco-elastic properties that can be inputted by the user at print-time as part of the fabrication process,” Rus added. The skins also allow the robot to land nearly four times more precisely, suggesting that similar shock absorbers could be used to help extend the lifespan of delivery drones. Dampers have many applications, from controlling the notes of a piano, to keeping car tires on the ground, to protecting structures like radio towers from storms.
The most common damper materials are ‘viscoelastics’ like rubber and plastic that has both solid and liquid qualities. Viscoelastics are cheap, compact and easy to find, but are generally only commercially available in specific sizes and at specific damping levels because of how time-consuming it is to customize them. The solution, the team realized, was 3D printing. By being able to deposit materials with different mechanical properties into a design, 3D printing allows users to program material to their exact needs for every single part of an object. “It’s hard to customize soft objects using existing fabrication methods, since you need to do injection molding or some other industrial process,” said Jeffrey Lipton, from MIT.
Using a standard 3D printer, the team used a solid, a liquid, and a flexible rubber-like material called TangoBlack+ to print both the cube and its skins. The cube robot includes a rigid body, two motors, a microcontroller, battery, and inertial measurement unit sensors. Four layers of looped metal strip serve as the springs that propel the cube. “By combining multiple materials to achieve properties that are outside the range of the base material, this work pushes the envelope of what’s possible to print,” said Hod Lipson, a professor at Columbia University in the US. ALSO READ: Scientists develop technique to send passwords through human body
Rus said that PVMs could have many other protective uses, including shock-absorbing running shoes and headgear. By damping the motion brought about by robots’ motors, PVMs are not only able to protect sensitive parts like cameras and sensors, but can also actually make the robots easier to control, researchers said. ALSO READ: Scientists develop a 3D food printer to create customized snacks