"UAV drones can fly for maybe 10 or 20 minutes before they need to charge again, whereas our bees can collect data for hours," said Prof Shyam Gollakota form the Paul G. Allen School of Computer Science & Engineering. "We showed for the first time that it's possible to actually do all this computation and sensing using insects in lieu of drones."
"We decided to use bumblebees because they're large enough to carry a tiny battery that can power our system, and they return to a hive every night where we could wirelessly recharge the batteries," said Vikram Iyer, a doctoral student in the UW Department of Electrical & Computer Engineering. "For this research we followed the best methods for care and handling of these creatures."
The team designed a sensor backpack that rides on the bees' backs and weighs 102 milligrams, or about the weight of seven grains of uncooked rice.
"The rechargeable battery powering the backpack weighs about 70 milligrams, so we had a little over 30 milligrams left for everything else, like the sensors and the localization system to track the insect's position," said co-author Rajalakshmi Nandakumar, a doctoral student in the Allen School.
GPS receivers are too power-hungry to ride on a tiny insect, so the team came up with a method that uses no power to localize the bees. They used multiple antennas that broadcast a signal from a base station across a specific area. A receiver in a bee's backpack uses the strength of the signal and the angle difference between the bee and the base station to triangulate the insect's position.
"To test the localization system, we did an experiment on a soccer field," said Anran Wang, a doctoral student in the Allen School. "We set up our base station with four antennas on one side of the field, and then we had a bee with a backpack flying around in a jar that we moved