Researchers at the Georgia Institute of Technology have created a new type of tiny 3D-printed micro-bristle-bot, size of the world's smallest ant, that moves by harnessing vibration from piezoelectric actuators, ultrasound sources or even tiny speakers. Swarms of these “micro-bristle-bots” might work together to sense environmental changes, move materials – or perhaps one day repair injuries inside the human body.
Some of the robots have four legs, while others have six. The Researchers made hundreds of the tiny structures to determine the ideal configuration. The prototype robots respond to different vibration frequencies depending on their configurations, allowing researchers to control individual bots by adjusting the vibration. Approximately two millimetres long – about the size of the world’s smallest ant – the bots can cover four times their own length in a second despite the physical limitations of their small size.
The vibrations move the springy legs up and down, propelling the micro-bot forward. Each robot can be designed to respond to different vibration frequencies depending on leg size, diameter, design and overall geometry. The amplitude of the vibrations controls the speed at which the micro-bots move.
The researchers have built a “playground” in which multiple micro-bots can move around as the researchers learn more about what they can do. They are also interested in developing micro-bots that can jump and swim.
The micro-bristle-bots are approximately two millimetres in length, 1.8 millimetres wide and 0.8 millimetres thick, and weigh about five milligrams. The 3D printer can produce smaller robots, but with a reduced mass, the adhesion forces between the tiny devices and a surface can get very large. Sometimes, the micro-bots cannot be separated from the tweezers used to pick them up.
A paper describing the micro-bristle-bots has been accepted for publication in the Journal of Micromechanics and Microengineering. The research was supported by a seed grant from Georgia Tech’s Institute for Electronics and Nanotechnology.
(Image Courtesy: Georgia Institute of Technology & YouTube)