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Droning on, part 1

I've been involved in the outreach program of Nevis Labs, the physics lab where I work. The goal is to inform the general public of what we do and where we do it. Part of that effort are the #ScienceOnHudson talks. You can see excerpts from these talks on Nevis' YouTube channel.

If you look at the list of talks, you'll see that I'm giving a talk in May on the history of Nevis Labs. It's a talk I've given before. The difference between my previous version of the talk and the one I plan to give in May is that I don't have to avoid discussing the science at Nevis for fear of boring the historical societies that were my previous audiences.

The historical narrative I present in my talk is center on the mansion house on the Nevis estate, which we now call the "Hamilton House at Nevis." I had an idea: For this special talk, why not include some form of motion? My idea was to take aerial footage of the Hamilton House and other parts of the Nevis property. It seemed to me that the best way to do that was to use a drone or quadcopter with a camera.

Thus begins my journey into the hobby of drone-flying.

I have a resource to learn more about drones. I've been playing board games at the HobbyTown in Nanuet NY. The store has a good selection of radio-controlled devices, including drones, and attracts a community of flyers. I asked the store's owner, Alex, to recommend a drone. My requirements: have a camera with a decent resolution; relatively easy to fly; inexpensive; stability was important; agility and speed were of no interest to me. He suggested the Dromida Vista FPV.

However, at the time he made the recommendation the Dromida Vista FPV had not yet been released. He based his suggestion on his experience with two other quadcopters the company made: the Dromida Ominus FPV (which had more expensive parts) and the Dromida Vista (which had lower maintenance costs, but didn't have a camera). So I had to wait. No worries; the weather in January was cold and I wasn't inclined to fly a quadcopter outside anyway.

Still, I was curious to see how well I could handle a drone. After doing a bit of on-line research, I decided to rush ahead and buy a cheap quadcopter for about $20: the UDI U839. My experience taught me that I should've waited a few days to ask Alex even about a cheap drone.

I got the UDI U839, read the instructions, charged the batteries, calibrated the drone. I turned up the throttle on the controller, heard the buzzing of the propellers, and felt the thrill of flying for the first time. (My cat, Shadow, did not care for the sound, and left the room in a huff. Well, maybe in a minute and a huff.) The thrill did not last. Despite the on-line reviews saying that the drone was easy to fly, I had the devil of the time controlling the thing.

My flight plan was simple: Get the drone in the air, let it hover, then land. Nothing fancy, not even a circle. I wanted to learn control one step at a time. The reality was that the drone shot up and slammed against my ceiling. I lowered the throttle, and the drone fell to the floor. I remembered my physics: If the lift generated by the drone is greater than its weight, it's going to continue to go upwards without limit. I had to continually "bounce" the throttle to keep the drone within a given height range. The problem was the throttle was sensitive; the drone either sped upward or sped downward.

Even so, the UDI would not remain stable. Even after I calibrated it (multiple times) and did not touch the directional controls, it would rapidly drift to the right and forward. My reflexes weren't fast enough to compensate. I tried several times, but never managed to gain even basic control of the drone.

I took the tiny drone to Hobbytown, and Alex was kind enough to evaluate it. He had better control of the UDI than I did, because he was an experienced flyer. Even so he had a hard time maintaining its position. The trim on the drone was badly off, and even adjusting the trim using the controller did not fix the problem.

I knew the UDI was a cheap piece of junk when I got it. I suppose I got my $20 worth of lessons from the experience.

I tried flying the drone one last time on my own. I had a brief moment of almost maintaining its position... and then there was one last crash. After that, the right front propeller stopped working. I fiddled with the drone, and was able to establish that the propeller itself was fine, and the motor could be coaxed into working occasionally, but the quadcopter's internal calibration was so badly off that it wouldn't spin that motor anymore. No amount of re-calibration would fix the problem for more than a few seconds.

Lessons learned: Talk to an expert before buying a drone; flying drones can be tricky; you get what you pay for.

I bought the Dromida Vista FPV and I've tried flying it a couple of times. I'll drone on about that experience in another post.