A disaster site. A rainforest. A battlefield. These places have something in common: we have a need to understand what’s going on where established infrastructure can’t give us good data.
Perching allows a quadrotor to shut down its power-hungry motors and let its sensors get to work acquiring data over an extended period of time, tracking parameters like the stability of a building after an earthquake, the nocturnal activity of a jaguar, or enemy troop movements. While perched, the quadrotor can also happily continue to operate in weather conditions that would make
At Stanford’s Biomimetics and Dexterous Manipulation Laboratory, we have been working on perching with the goal of making landing on a wall as easy as landing on the ground. By adding a few grams of structure and mechanism to an off-the-shelf commercial quadrotor, we are now able to perch on both vertical and inverted surfaces without using any special firmware or flying techniques. While it’s still not as foolproof as landing on a level surface, we are closer than ever to making perching accessible outside of a research environment.
…By simply flying the quadrotor straight into the wall the rotors reliably bring the mechanism [mounted on the top of the copter] into contact to engage the wall using an opposed grip created by two sets of microspines—hardened steel spikes on a special suspension— along a surface in opposite directions. The spines catch against tiny bumps and pits on the surface and hang on using friction.
This is a very cool idea. One can imagine all sorts of applications in which the vehicle is disposable – the mission is simply to get the sensors in place swo that they can transmit until the batteries are gone. The article goes into considerable detail about how this works.