This autonomous solar-powered robot costs 1p, is smaller than a grain of salt, and communicates through 'wiggles of a little dance'

• Researchers created fully autonomous robots smaller than a grain of salt
• Robots swim using electrical fields to manipulate ions in the surrounding fluid
• The propulsion system allows coordinated movement and speeds up to one body length per second

Researchers at the University of Pennsylvania and the University of Michigan claim to have created the world’s smallest fully programmable, autonomous robots.

Each robot measures roughly 200 by 300 by 50 micrometers, smaller than a grain of salt, and operates at the scale of biological microorganisms.

The robots function without tethers, magnetic fields, or external joysticks, making them the first truly autonomous devices of this size.