@Farkhod_Khikmatov Thanks for taking a look! I’m not sure I understand what you’re referring to - when I look at the most recent log and graph RCOUT.C1 and C2, my two motors, they seem to average around 50% throttle (or less) in hover, at least until I lost control of the aircraft. Of course lower would be better, but I would think 50% is okay for hovering with plenty of headroom left over for maneuvers. Am I missing something? Thanks again for the help.
Well, I’m still at it, trying to figure this thing out. I had another couple flights today, and tried to get an entire flight on the small dataflash chip this FC has. After looking at the log to the best of my ability, I think the conclusion I’m coming to is that when oriented vertically, the tailsitter is unbalanced with the battery on the bottom side giving too much weight to that side and causing the flight controller to constantly be fighting to keep the nose up, especially when any breeze comes along. Since this is a very small aircraft to begin with, the battery is already quite small, but I have 550 and 450mah 4S packs I could try instead of this 650mAh. Does anyone else notice anything in the log? I’m attributing the crash at the end to this imbalance as well, though it was quite strange to see the vehicle spiral essentially out of control. I tried to save it with FBWA, but that didn’t help, and unless I had great reflexes, I don’t know if Manual flight mode would’ve been able to save it either.
Any insights on the log you can share would be great! I was looking at the QSTABILIZE sections of the log which led me to believe the vehicle is imbalanced.
V2 new eCalc COG \u0026 4S_650mah.bin
Hey do you have a picture of your setup? You are absolutely correct about your diagnosis. One common thing I would recommend, add a control surface; it helps a lot. First fix the issue and then add control surface.
Hi @Farkhod_Khikmatov here is a link to a photo Sign in to your account
The only difference between what I most recently flew and what I have in the photo is that I am now using a different flight controller (still Ardupilot) and that I increased the size/length of the elevons by about 30% front to back). I’m not sure what you mean by add a control surface. I have been using control surfaces (elevons) the entire time, as this was never a control-surface-less build. Thanks for your time on all this, I really think I should be able to get this to work, but my current thought is that my copter/vertical configuration CG is too far off for the aircraft to compensate, which is what causes the loss of control in descent/hover.
Yes this non vectored tailsitter is very hard to get right. Correct Cg placement is necessary. It can’t be too nose heavy or tail heavy. If you need a ready frame. I have two ready frames I can send you bro. I am located in United states. It’s just sitting at home and not being used. 100 bucks I’ll give it away. You just have to load Marcos parameters and it will work
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Thanks @Farkhod_Khikmatov that’s really generous of you! Do you have any photos of your airframes? I don’t think they would work for my end goal, which is to have a class build project of a tailsitter - but I’m still curious.
its just Explora Tailsitter. my email is khikmatov.farkhod@gmail.com
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