Two insect-like robots, a mini-bug and a water strider, developed at Washington State University. Two groundbreaking insect-inspired robots,...
 |
| Two insect-like robots, a mini-bug and a water strider, developed at Washington State University. |
The mini-bug, weighing a mere eight milligrams, and the water strider, weighing 55 milligrams, hold tremendous potential for diverse applications. These miniature marvels could revolutionize fields such as artificial pollination, search and rescue missions, environmental monitoring, micro-fabrication, and even robotic-assisted surgery.
Conor Trygstad, a PhD student in the School of Mechanical and Materials Engineering and lead author, highlights the impressive speed of these micro-robots, moving at about six millimeters per second. Though slightly slower than their biological counterparts, the robots outshine other micro-robots at their scale.
The key to their exceptional performance lies in their tiny actuators, the components responsible for their movement. Trygstad ingeniously utilized a novel fabrication technique to miniaturize the actuator to less than a milligram, setting a record for the smallest ever created. Néstor O. Pérez-Arancibia, Flaherty Associate Professor in Engineering at WSU's School of Mechanical and Materials Engineering and project leader, emphasizes that these actuators are the smallest and fastest ever developed for micro-robotics.
The actuator's innovation lies in the use of a shape memory alloy, a material capable of changing shape when heated. This 'shape memory' ability, allowing it to return to its original form, eliminates the need for traditional motors with moving parts. Remarkably lightweight, the actuator opens new frontiers in micro-robotics.
While shape memory alloys are typically deemed too slow for large-scale robotic movement, the WSU robots employ 1/1000-inch diameter wires made of this material. With minimal current, these wires heat and cool rapidly, enabling the robots to achieve up to 40 movements per second. In preliminary tests, the actuator demonstrated lifting over 150 times its own weight.
Conclusively, the SMA technology not only facilitates efficient movement but also demands minimal electricity or heat, making it a highly resource-efficient option. Trygstad envisions further exploration, drawing inspiration from water striders' efficient movements. The team aspires to create a water strider-type robot capable of gliding both on and just below the water surface, working towards autonomy with tiny batteries or catalytic combustion, liberating these robots from external power sources.