Scientists at the Max Planck Institute for Intelligent Systems (MPI-IS) have developed hexagonal robot components, called modules, that can be assembled LEGO-style to create high-speed robots that can be rearranged for a variety of functions. A team of researchers from the Robotics Materials Department at MPI-IS, led by Christoph Keplinger, integrated artificial muscles into a hexagonal exoskeleton with embedded magnets, enabling rapid mechanical and electrical connections. The team’s study, “Hexagonal electrohydraulic modules for rapidly reconfigurable high-speed robots,” will be published in the journal Science Robotics September 18, 2024.
Six lightweight rigid plates made of fiberglass serve as the exoskeleton of each HEXEL module. The internal joints of the hexagons are actuated by hydraulically amplified self-healing electrostatic (HASEL) artificial muscles. When high voltage is applied to the module, the muscles are activated, causing the hexagonal joints to rotate and change shape from long and narrow to wide and flat.
“Combining soft and rigid components in this way allows for high strokes and high speeds. By connecting multiple modules, new robot geometries can be created and reused to meet changing needs,” says Ellen Lumley, a visiting researcher at the University of Colorado Boulder. She and Zachary Yoder, a PhD student working in the Department of Robotics and Materials, are co-first authors of the publication.
In the video, the team demonstrates a variety of behaviors that can be created with HEXEL modules. While groups of modules can crawl through narrow gaps, single modules can act so fast that they leap into the air. Multiple modules can be connected into larger structures to create different behaviors depending on how the modules are attached. For example, the team created a robot that rolls quickly by combining multiple modules.
“In general, developing robots with reconfigurable capabilities makes a lot of sense. It’s a sustainable design option. Instead of buying five different robots for five different purposes, you can build many different robots using the same components. Robots built with reconfigurable modules can be reconfigured as needed to provide a wider range of capabilities than specialized systems, which can be beneficial in resource-constrained environments,” Yoder concluded.
