2024-09-20 マックス・プランク研究所
Several HEXEL modules form a robot that rolls over sand.
© MPI-IS / Wolfram Scheible
＜関連情報＞
- https://www.mpg.de/23489134/electrohydraulic-modules?c=2249
- https://www.science.org/doi/10.1126/scirobotics.adl3546
高速再構成可能な高速ロボット用六角電気油圧モジュール Hexagonal electrohydraulic modules for rapidly reconfigurable high-speed robots
Zachary Yoder, Ellen H. Rumley, Ingemar Schmidt, Philipp Rothemund, and Christoph Keplinger
Science Robotics Published:18 Sep 2024
DOI:https://doi.org/10.1126/scirobotics.adl3546
Editor’s summary
Reconfigurable, modular robots are an appealing approach to developing versatile systems, but because of soft actuators’ slow actuation speeds, low force output, and tethered configurations, they have mostly been limited to heavy, bulky motors. Using electrohydraulic actuation, Yoder et al. developed a hexagonal-shaped modular robot that provides high-speed and high-strain actuation. Four electrohydraulic actuators located at the junctions of a hexagonal array of stiff plates drive a rapid shape change in the hexagon from tall and narrow to wide and short. Magnets embedded in the plates allow the modules to connect in honeycomb-like lattices for multimodal actuation, such as a high-stroke muscle hanging configuration and a rolling wheel–like configuration. —Melisa Yashinski
Abstract
Robots made from reconfigurable modular units feature versatility, cost efficiency, and improved sustainability compared with fixed designs. Reconfigurable modules driven by soft actuators provide adaptable actuation, safe interaction, and wide design freedom, but existing soft modules would benefit from high-speed and high-strain actuation, as well as driving methods well-suited to untethered operation. Here, we introduce a class of electrically actuated robotic modules that provide high-speed (a peak contractile strain rate of 4618% per second, 15.8-hertz bandwidth, and a peak specific power of 122 watts per kilogram), high-strain (49% contraction) actuation and that use magnets for reversible mechanical and electrical connections between neighboring modules, thereby serving as building blocks for rapidly reconfigurable and highly agile robotic systems. The actuation performance of each hexagonal electrohydraulic (HEXEL) module is enabled by a synergistic combination of soft and rigid components; a hexagonal exoskeleton of rigid plates amplifies the motion produced by soft electrohydraulic actuators and provides a mechanical structure and connection platform for reconfigurable robots composed of many modules. We characterize the actuation performance of individual HEXEL modules, present a model that captures their quasi-static force-stroke behavior, and demonstrate both a high-jumping and a fast pipe-crawling robot. Using embedded magnetic connections, we arranged multiple modules into reconfigurable robots with diverse functionality, including a high-stroke muscle, a multimodal active array, a table-top active platform, and a fast-rolling robot. We further leveraged the magnetic connections for hosting untethered, snap-on driving electronics, together highlighting the promise of HEXEL modules for creating rapidly reconfigurable high-speed robots.
