University of Washington researchers have sent insects on a drone flight. The development has created a kind of “living IoT platform” that could complement the work of agricultural drones. They conducted research with three different species. The tests showed that bees can carry a load of 105 milligrams, so the developers designed their own chip to weigh just 102 milligrams.
A typical task of a conventional drone might be to collect data – even in visual form. The biggest limiting factor, however, is the battery, which often only allows a drone to fly for about 30 minutes without recharging. So, while studying “nature’s most perfect flying device”, the researchers also wanted to find a way for their device to “feed and rest” – or recharge – itself.
Under the magnifying glass, the miniature development. The largest part of the chip’s mass (70 milligrams out of 102) is a rechargeable lithium-ion battery – with an operating time of about seven hours. The remaining 32 milligrams contain the microcontroller, antenna and sensors that analyse humidity, temperature and brightness every four seconds.
In order to maximise the efficiency of the battery, as few components as possible have been incorporated. Instead of “power-hungry” radio modules, the researchers were able to receive data from the chips by modifying the radio signals. The data transfer rate is about 1000 bits per second.
Positioning is also crucial, but a built-in GPS would drain the battery very quickly and add weight. Instead, the designers placed radio transmitters around the flight area where the experiment took place, which would signal when the bees under investigation were detected within 80 metres. Once the insects have returned to the hive, the tiny battery can be charged wirelessly, but the developers are also considering the use of solar panels.
The researchers’ primary goal with this particular experiment is to help smart farms pollinate flowers. And the measurements from the moisture and light sensors can be used to help them water more accurately. There is another potential benefit: perhaps the living “mini drones” will help solve the mystery behind the drastic decline in bee populations.