Redesign/Rebuild Cont…

I definitely skipped a few steps here which is supposed to be my official record of my projects and things. At any rate, nothing went right in between there and here. It took a while to get the motor phases right, getting the flight controller upgraded and connected right. Then having to fight with a totally unexplainable problem with the drones just NOT arming.

Despite the fact that the drones were bound to a transmitter and all motor tests showed the motors were in fact working.

Oh… and the binding process… damn good thing I bought that Orange RX receiver. But it didn’t matter to much at first because the tutorial I was following made a major assumption about the people following along having something. Which, they did, until they were instructed to cut it in half… only to later need it to bind the satellite receiver.

No alternate instructions were given for binding the flight controller through software, only by using a working and powered receiver with a satellite connection. In the end, I had to purchase a Lemon RX Receiver and satellite antenna to complete binding the QAV250 drone.

Apparently the lesson here is, watch the whole friggin tutorial set with a critical eye *before* the build.

I nearly blew up the 1300mAh Lipo I was using to test the S500, in a foolish move, despite the little voice in my head telling me to double check how to mount the power cables, I managed to solder the + and – in series. Plugged the Lipo in for a power test and… geee…. why do I smell smoke… and why is this cable so hhooooooooottttttt…..

I quickly disconnected the battery as it started to INFLATE and ran for the front door to put it out on the concrete. As the Flite Test term, puffy batteries goes, a hot Lipo beginning to inflate (or get puffy) is a sure sign of a Lipo fire. So I was in rather a rush to get the damn thing out of the apartment. Even though the battery continued to inflate as I hauled it out into the front yard, thankfully, it did not burst into flames. But the Blue Smoke Monster visited and almost got loose…. thank goodness for stupid luck.

I was able to still use it until it’s charge ran out after I fixed the numbskull error in soldering. But I was pretty sure the battery, if not completely hosed, at least lost a great deal of it’s “life”. I did manage to charge it again with no trouble, although I definitely put it in a fireproof travel pouch and kept a close eye on it, touching it every few minutes to feel for heat changes and watching the surface for…. puffiness. 🙂 In retrospect, I probably should have used my Infrared thermal scanner to keep an eye on the temperature without having to get to close to it… and I probably should have charged it someplace within easy reach of tossing it out a window… I wasn’t a total fool, I took several precautions, but still in hindsight… they were lacking just the same.

I will say one thing, when Flite Test was reviewing the Lipo bunker thingy, they intentionally caused Lipos to explode. The fire was… unsettling and spectacular… but, I was surprised how much power it took and how long it took for the batteries to burst. Manufacturing defects and damaged casing not withstanding the batteries seem to be quite stable. This is the only reason I attempted to recharge the Lipo. The battery was not nearly close to the same state as the batteries in the Flite Test YouTube video. That being said, I still ordered a new one and will use this one as a backup with an eye toward sending it to recycling at some point as I don’t trust the battery completely anymore.

I also realized that the balance ends are super short… with reason, but this makes it hard to place the battery in a protective case or pouch since some portion of it must remain outside and connected to the charger. I would prefer the battery being completely in the protective “thing” with a quick disconnection in the event the thing goes off so you can seal the container (if not self-sealing) and get it outside… or at least buried in a nearby bucket of sand. Anyhow, just thinking out loud.

Anyhow, some pics. The QAV250 now named Pipsqueak, not quite under 250g, unfortunately, and the S500 in process of assembly and testing.

The first image, I am in the middle of checking communications, motor checks and binding… which I could not complete sans satellite receiver serial cable…. grr…

This is the completed drone, Pipsqueak, bound, power checked… all but first flight.

While waiting for the serial cable, I started working on the S500…

The good news, the build went faster and binding was easier. However, like the QAV250, I ran into Arming issues. For the S500 I just disabled disarm, but I suspect having learned what was preventing arming on the QAV250, I can fix the arming issue with the S500 also.

Lastly, with regards to the build, I discovered I bought the wrong props for the S500’s motors… so… I have to order more, for sh*ts sake. Also, I might have to rework the battery connection cables and heads, they may be too long on both drones.

Lastly, for this post, since the QAV250 was already seemingly going to be heavier then 250g, I just broke down and got the FAA Section 336 drone license. I read up on the part 107 Remote Pilot Certificate, and I might get that as well, but time will tell. Aside from the waiver system, the restrictions imposed by 336 and 107 also include line of sight. While altitude restrictions don’t bug me so much, one of the goals with my drones was to experiment with autonomous aircraft, as part of my interest in Robotics.

The line of sight rules kills any possibility of GPS guided drones without the 107 certification and a waiver (which would likely require a damn good explanation for why I was doing it)… anyhow, we shall see what the future holds.

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