By: Megan Tseng
On August 26th 2020, scientists published findings on successfully creating the first microscopic mobile robots controlled by electrical signals.
These newly developed robots provide a foundation for much more complex devices that can utilize advanced intelligence systems and perform a variety of tasks within human tissues.
The idea is not new; researchers have experimented with creating miniature robots that can be controlled and eventually used to collect data or transport substances on a microscopic level. However, finding adequate power sources or materials remained a challenge. Heat diffuses too quickly on a microscopic scale to provide sufficient power for the robot, and parts modeled after organic muscle are easily damaged by chemicals in the manufacturing process.
Artwork depicting the microscopic robots.
Each robot is made of a simple circuit, functioning as a head, and body, and legs. The circuit is made of silicon photovoltaic devices, which convert light into electricity, and the legs are made of 7-nanometers-thick platinum strips that drive an electrochemical process. The entire robot is only 5 microns tall, 40 microns wide, and 40-70 microns long.
When the robots are in water, electrically charged ions attach to the platinum legs, and causinge them to curl. Researchers flash laser pulses at specific photovoltaics, which produce a small amount of electricity surrounding their corresponding set of legs. This electricity is enough to repel the ions on the platinum, allowing the legs to straighten. By flashing alternating laser pulses at the front and back legs, the robot’s legs can straighten and curl in a way that will allow it to “walk” at a speed of 60 microns per minute.
Researchers compare future developments with these microscopic robots to “shrinking yourself down.” With the implementation of electronic devices and computation mechanisms, they can potentially conduct research in the microscopic world that our current technology cannot accomplish. More advanced versions can also help medical professionals in suturing blood vessels, reconstructive surgery, or just collecting data within areas of the human body.
Choi, Charles. “Scientists Create Laser-Powered Robots.” Inside Science, 26 Aug 2020, www.insidescience.org/news/scientists-create-microscopic-laser-powered-robots.
“Microscopic robots ‘walk’ thanks to laser tech.” Science Daily, 26 Aug 2020, www.sciencedaily.com/releases/2020/08/200826113715.htm.