Scientists put backpacks on dragonflies to track their brains in flight
June 18, 2013
Electrodes inserted into the dragonfly’s body and brain record the electrical activity of neurons, and a custom-made chip amplifies the signals and transmits them wirelessly to a nearby computer.
The researchers came up with a clever solution to power the chip without adding so much mass that the insects couldn’t get off the ground, based on the same technology found in the RFID key card access system used in many office buildings.
There, a reader, usually a small pad next to a door, emits radio waves to create a magnetic field. When a key card gets close enough to the reader, the magnetic field induces a current that powers a chip inside the card, enabling it to transmit a code to unlock the door.
The two long antennae on the dragonfly backpack harvest radio waves and power the chip in a similar way. Eliminating the need for a battery on the backpack was the key to keeping the weight down. [...]