A CAMERA small enough to fit on the back of an insect could help revolutionise precision agriculture.
The University of Washington (UW) in the United States this week announced it had come up with a working camera, weighing in at a preposterously light 250 milligrams, or a fifth of the weight of a quarter teaspoon or salt, that can be fitted to the back of a bug.
The wireless, steerable camera can stream video to a smartphone at 1 to 5 frames a second is fitted on a mechanical arm that can swivel 60 degrees, allowing a high resolution, panoramic shot or track a moving object.
As part of the research the university team mounted the camera on top of live beetles and insect sized robots.
The team was confident the breakthrough could help scientists better understand insect behaviour.
We have created a low-power, low-weight, wireless camera system that can capture a first-person view of whats happening from an actual live insect, said senior author Shyam Gollakota, a UW associate professor.
Vision is so important for communication and for navigation, but its extremely challenging to do it at such a small scale, Prof Gollakota said.
One of the major challenges was developing a system that did not use much power.
Typical small cameras, such as those used in smartphones, use a lot of power to capture wide-angle, high-resolution photos, and that doesnt work at the insect scale.
While the cameras themselves are lightweight, the batteries they need to support them make the overall system too big and heavy for insects to cart around.
So the team took a lesson from biology.
Similar to cameras, vision in animals requires a lot of power, said co-author Sawyer Fuller, a UW assistant professor of mechanical engineering.
Its less of a big deal in larger creatures like humans, but flies are using 10 to 20 per cent of their resting energy just to power their brains, most of which is devoted to visual processing, Prof Fuller said.
To help cut the energy cost, some flies have a small, high-resolution region of their compound eyes.
They turn their heads to steer where they want to see with extra clarity, such as for chasing prey or a mate.
This saves power over having high resolution over their entire visual field.
To mimic an animals vision, the researchers used a tiny, ultra-low-power black-and-white camera that can sweep across a field of view with the help of a mechanical arm.
The arm moves when the team applies a high voltage, which makes the material bend and move the camera to the desired position. Unless the team applies more power, the arm stays at that angle for about a minute before relaxing back to its original position.
This is similar to how people can keep their head turned in one direction for only a short period of time before returning to a more neutral position.
Using the system a a moving object can be tracked without having to spend the energy to move a whole robot.
These images are also at a higher resolution as the pixels are concentrated on the subject rather than the entire wide angle field.
The researchers attached their removable system to the backs of two different types of beetles a death-feigning beetle and a Pinacate beetle.
Similar beetles have been known to be able to carry loads heavier than half a gram, the researchers said.
Loaded with the cameras, the beetles could still move freely and were observed walking on gravel, uphill and even climbing trees.
The implications for precision agriculture are enormous as farmers could be able to understand how insects interact with the crop and where potential problems are beginning.