7in quad with DJI 04 pro very odd behaviour

ArduCopter Copter 4.6
1

I built this quad a few months back and it flew really nicely. I recently put a dji04 pro on it and now its acting odd. I attached a link of the bin and video. In the video you will notice that I take off and she rolls to the right and won’t respond, then when I fly out to the field it stops on its own with a hard pitch back and I didn’t tell it to do that. Maybe someone can take a look and tell me what I am missing. Its hardware it speedybee f405 with 60amp esc, radiomaster elrs xr4 rx. all equipment is updated to the latest firmware.

2

Not sure if that’s a case but sbus on o4 conflicting with elrs because it wired to same pin R2, just cut sbus wire.

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thats true, i didn’t think about that

4

O3 had no problem with that.

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@mike_tk I was really hoping that was the issue but no, just did a test flight and not any better.

6

Check your vibrations level, set INS_HNTCH_FREQ to something lower - like 80 - you have not requested movements on pitch.
Also you have noticeable imbalance, your motors 1 and 3 working much harder than 2 and 4, that can be a reason.

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7

The quad hovers at %5 throttle so it should be able to compensate for the imbalance, I have rebalanced the quad and it didn’t change anything.
Your are correct I didn’t request any pitch movements but the quad responded in hard pitch moves. you can see it in the video.
vibrations are within normal range.

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Thanks for taking a look.

8

I don’t think this is a fw issue even though I did upgrade to 4.6 stable from 4.5.7.

I guess I will remove the 04 pro unit and see if it goes away.

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I downgraded to 4.5.7 just to see… and still doing it.

10

What happened to that plan?

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I figured I would do the easiest thing first. I unpluged it just now and no difference.

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Motor 3 (RC4) and motor 1 (RC2) - the front motors - are running at minimum. So basically they since they can’t slow down any more and your hitting a control saturation. I get the impression this quad is well powered.

MOT_SPIN_MIN and MOT_SPIN_ARM are too high (still on default). Especially _MIN. Verify with the motor test but I bet you could drop those down to _ARM .05 and _MIN,0.08.

Might also want to check that the center gravity. I suspect it’s a bit tail heavy.

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You still need to look in balance It’s clear that 4 and 2 get down saturated and 1 and 3 getting spikes on movements change.

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your min/arm values are absolutely correct when tested I updated them, I also am putting a heavyer battery on (normally I run 5000mah, but I am putting a 10000mah) I want to see if that helps. I will rebalance after adding the heaver battery.

You are correct it is very well powered, didn’t plan for that.
I use custom built li-ion battery packs because I like to fly slow.
Side note I may add a 15000mah pack just to see if I can chill it out a bit, its like a sport bike and I want a cruiser. I know by adding the heaver weight I will need to retune the PIDs etc.