By taking a unique approach to its design, scientists have created what they say is the world’s smallest neglected flying robot. To minimize size and weight, they moved the bot’s power and control system out of its sub-centimeter-wide body.
With a width of just 9.4 mm and tilting the scale at 21 mg, the robot is being developed by Professor Liwei Lin of the University of California, Berkeley and colleagues.
It mimics the Bumblebee’s flying ability. Like that insect, it hoveres in place, moving both vertically and horizontally, hitting small targets. Its offspring can one day perform tasks such as pollinating crops, or explore small spaces to access ordinary drones.
The bot’s 3D printed polymer body consists of four blade horizontal propellers surrounded by a “balance ring.” Protruding from the center of the propeller is a small vertical ring that holds two packed neodymium permanent magnets.
Adam Lau/Berkeley Engineering
The robot is driven and piloted by alternating magnetic fields generated externally along a single axis.
When the two magnets of the bot are simultaneously attracted to the field and repelled, the attached propeller rotates to create a lift. When the robot is in the air, its balance ring adds rotational inertia and creates a gyroscope effect that increases stability.
Evenly increasing or decreasing the strength of the magnetic field moves the robot up and down by spinning faster or slower respectively. And by varying the strength of the magnetic field over a horizontal distance, the bot can be moved forward, backward, or sideways accordingly.
Adam Lau/Berkeley Engineering
Scientists are currently planning to add sensors that allow robots to maintain stable flight by self-correcting variables such as wind power. They also want to make the device even smaller, reducing energy requirements by utilizing weak magnetic fields.
A paper on the research was recently published in the journal Science Advances.
Source: UC Berkeley
