A team of scientists has built the smallest remote-controlled robot, only half a millimeter wide.
Extremely small robots have a lot of potential uses, from help with surgical procedures to repairing machines in places where a key can’t fit. The smaller they get, the more scenarios could be used.
This robot, although not ready to go out into the world and make repairs yet, is truly impressive. It looks and moves like a miniature crab, a shape chosen from a “creative whim”, according to researchers. The techniques they have developed can, in fact, be used to develop small robots into almost any shape needed.
“Our technology allows for a variety of controlled motion modes and can go at an average speed of half body length per second,” says mechanical engineer Yonggang Huang of Northwestern University in Illinois.
“This is very difficult to do on such a small scale for terrestrial robots.”
The technology on which the robot is based was originally developed eight years ago: the robot parts are fixed on a stretched rubber substrate, and when the material is relaxed, the device comes out in its shape.
This crab robot can do a lot of repairs
By carefully calibrating the basic parts, the shape of the robot can be precisely controlled. A similar approach is used with moving parts of the robot, which are made of a shape memory alloy material. These materials switch between two different shapes, depending on whether or not they are heated.
Lasers, acting as a remote control, are used to heat certain parts of the robot – as those parts turn into a different shape, they propel the crab forward. There is no need for a power supply or motor, and a thin layer of glass ensures that the components return to their original shape as they cool.
“Because these structures are so small, the cooling rate is very fast,” says materials researcher John Rogers of Northwestern University. “In fact, reducing the size of these robots allows them to run faster.”
By directing lasers at different sections of the crab robot, researchers are able to determine the direction of locomotion. By adjusting the laser scanning frequency, the robot’s motion speed can also be changed.
This is the next step in a trend that has seen robots become smaller and smaller over time, either to make them more resistant to external forces, to target disease-treating drugs, or to build larger, modular parts. smaller.
Researchers say their new process has potential: they can cause robots to turn and jump using the same techniques, for example. As long as the robot is in a line of sight to the laser, it can be manipulated remotely.