Flying is an energy-intensive activity. The birds and the bees don’t hover around incessantly like your little sister’s quadcopter. They flit to and fro, perching on branches and leaves while they plan their next move. Sure, a quadcopter can land on the ground, but then it has to spend more energy getting back to altitude. Researchers at Harvard decided to try to develop flying robots that can perch on various surfaces like insects can.
Perching on surfaces happens electrostatically. The team used an electrode patch with a foam mounting to the robot. This allows the patch to make contact with surfaces easily even if the approach is a few degrees off. This is particularly important for a tiny robot that is easily affected by even the slightest air draft. The robots were designed to be as light as possible — just 84mg — as the electrostatic force is not particularly strong.
It’s estimated that perching electrostatically for a robot of this size uses approximately 1000 times less power than during flight. This would be of great use for surveillance robots that could take up a vantage point at altitude without having to continually expend a great deal of energy to stay airborne. The abstract of the research paper notes that this method of perching was successful on wood, glass, and a leaf. It appears testing was done with tethers; it would be interesting to see if this technique would be powerful enough for a robot that carries its own power source. Makes us wonder if we ever ended up with tiny flyers that recharge from power lines?
We’re seeing more tiny flying robots every day now – the IMAV 2016 competition was a great example of the current state of the art.