Researchers at the Universities of Michigan and Pennsylvania have introduced the world’s smallest programmable, autonomous robot.
Swimming microbots have been designed for deployment in the medical industry, capable of monitoring individual cell health and helping with the creation of “micro devices”.
Measuring approximately 200 by 300 by 50 millimeters (smaller than a grain of salt), the tiny robots are designed to independently sense and navigate their surroundings, detecting temperatures to within a third of a degree Celsius.
Their temperature sensitivity also means they can move toward areas of increasing temperature, and use heat variations to monitor cellular-level health. Changes in temperature are communicated by the robot through a “waggle dance,” similar to what bees do to communicate.
According to the team, the microbots can operate for months and cost only a penny each.
“We have created autonomous robots 10,000 times smaller,” Said Mark Miskin, assistant professor in electrical and systems engineering at Penn, in a press release. “This opens up a whole new scale for programmable robots.”
Working in water generally brings problems with drag and stickiness. Instead of attempting to move directly against resistance, the team developed a propulsion system that moves the surrounding water.
The robots generate an electric field that pushes ions into the liquid, which then push nearby water molecules, creating enough force to move the robot.
By adjusting this electric field, the robots can travel in complex patterns or coordinate into groups similar to a school of fish, and reach speeds of up to one body length per second.
Microbots are operated and programmed using light pulses, and each has a unique identifier that enables individual programming. This makes it possible for groups of robots to divide tasks, with each unit performing a different role.
The researchers say this work represents the first time that a sub-millimeter robot has been equipped with a complete computing system, including processor, memory and sensors.
Looking ahead, the team said future iterations of the microrobot could store more complex programs, move faster, integrate additional sensors or work in more demanding environments.
“This is really just the first chapter,” Miskin said. “We’ve shown that you can put a brain, a sensor, and a motor into something almost too small to look at, and keep it alive and working for months. Once you have that foundation, you can layer on all kinds of intelligence and functionality. It opens the door to a new future for robotics at the micro level.”
