Tuesday, April 11, 2017

2017-04-11: Autonomy Incubator Implements Novel Tethered Flight Solution

The tethered Hive UAV in flight

Tethers. They let us conduct quick outdoor flight tests without the paperwork involved with untethered UAV flight, but logistically, they can be complicated— string and propellers do NOT mix, so keeping the tether under control is imperative. For smaller vehicles like the ones we flew during our outdoor package delivery mission last summer, our solution was to tether the vehicle to a fly fishing rod and follow it around:

Pretty clever, right? However, now we're working with The Hive, a vehicle with twice the weight and over double the thrust of the quadrotor we used last year. The fishing line is too thin to hold this machine, so we have to use nylon cord. And without the finesse and precision of a fishing reel to control the line, the cord is in danger of getting blown up into the propeller and damaging the vehicle.

Enter Zak Johns, the Ai's expert drone pilot and master problem-solver with a solution.

Zak Johns inspects the Hive UAV, ozone sensor payload, and tether

By feeding the tether through a length of flexible tubing attached to the body of the UAV, Zak ensures that the cord always stays well clear of the props— even during takeoff and landing, when the air under the vehicle is the most turbulent.

The winds today were gusting at 35 mph, and it still performed perfectly.
Now that we have a simple, easy way of managing the tether for large UAVs, our outdoor flight abilities just became way more agile. Like for our OWLETS atmospheric science mission coming up next summer! Check it out here to see what we're doing.