In a groundbreaking development at Washington State University, researchers have unveiled two insect-like robots, a mini-bug, and a water strider, setting records as the smallest, lightest, and fastest fully functional micro-robots ever created. Weighing a mere eight milligrams and 55 milligrams, respectively, these micro-robots boast speeds of about six millimeters per second, showcasing potential applications in artificial pollination, search and rescue operations, environmental monitoring, micro-fabrication, and even robotic-assisted surgery.
The miniaturization breakthrough lies in the tiny actuators propelling these robots. Lead author Conor Trygstad, a Ph.D. student in the School of Mechanical and Materials Engineering, employed an innovative fabrication technique to create actuators weighing less than a milligram—setting a new standard for micro-robotics. These actuators, utilizing a shape memory alloy, change shapes when heated, enabling controlled movements without conventional motors’ moving parts or spinning components.
Néstor O. Pérez-Arancibia, Flaherty Associate Professor in Engineering at WSU’s School of Mechanical and Materials Engineering, who led the project, emphasized that these actuators are the smallest and fastest ever developed for micro-robotics. The robots’ agility is attributed to shape memory alloy wires, each with a diameter of 1/1000 of an inch, allowing the robots to move their fins or feet at remarkable speeds—up to 40 times per second.
This breakthrough technology not only facilitates swift, precise movements but also significantly reduces the electricity or heat required to operate the robots. The shape memory alloy system, being mechanically sound, opens new frontiers in micro-robotics. Preliminary tests even showcased the actuator’s capability to lift over 150 times its own weight.
Inspired by water striders’ efficient leg movements, the researchers aim to enhance their robots’ capabilities, potentially creating water strider-type robots capable of moving across the water surface and underneath. Future developments may include integrating tiny batteries or catalytic combustion, making these micro-robots fully autonomous and untethered from external power sources. The era of micro-robotics is marked by these groundbreaking achievements, heralding a new wave of possibilities in various fields.