Derek's ECHO 290 FPV Quad Resurrected

[Derek]

Maybe two weeks ago.

[danhampson]

have you tried re-flashing the board?

[Graham Lawrie]

Derek, when i calibrate the ESC,s i put the motor slider to the top first, then connect the battery, hear the bleeps, then move the slider to the bottom. I dont wait for the motors to spin up?

[Derek]

Right...that's how I did it. I hope I didn't state it otherwise. Im still wanting to get this quad flying but, for the time being, my 5.8ghz fpv is going on the new Skyfun.

[Derek]

I just had a realization.....I think I found why my quad isn't flying properly. Check this pic:

Naze on Echo290.jpg (182.8 KiB) Viewed 2854 times

When I originally designed this quad, I had no intentions of putting the Hobbypartz ActionCam on the nose. I had intended on using a Mobius cam on top and the FPV cam on that nose tray. That being said, I mounted the Naze32 board right in the middle of the motor arms. However, because I mounted the HobbyPartz cam on the nose, there is much more weight on the nose than the weight of an FPV cam.....basically, more weight out in front of center.

So, let me ask this....because the Naze32 isn't actually in the middle of the quad (from nose to tail), this is probably throwing off the gyros and now I'm getting non-adjustable over-compensations, right? What do you think?

[pvolcko]

The controller shouldn't have to be dead center of the model, just squared up to the three axes, just like with an FBL in a heli.

Is your center of gravity dead center? That will screw with things. If you're nose heavy then you'll end up needing to fight that. The controller will do some compensation, but you will end up tilting before too long and have to correct for it with the sticks.

I'm going to have to reread this thread to see what the issue is you're having.

[Derek]

Ok, that makes sense. COG is probably the most important aspect of the hobby. So...with the action cam on the nose, I'll need to make sure that the battery is far enough rearwards to balance things out. Now, let me ask this potentially stupid question that I may already know the answer....the CoG should, more or less, be the dead center between the front and rear motors...right?

as for the issues that I've been having....i'm not real sure that I've given many specifics. I'm pretty sure that all I've said was that I stripped down my original ECHO 290, rebuilt it with less materials, and now it flies like crap. It's nearly midnight right now so I won't be able to share any video right now but, if the weather here permits, I'll take the quad and a video camera outside and I'll get some video of what the quad is doing and we'll go from there.

[Stambo]

I have always mounted my Naze boards right in the middle of the motors and tried to keep the CG right where the Naze is.
I am not sure that this is critical but mine always fly pretty well so I am not about to try anything different.

[Derek]

Ill work on it...

[pvolcko]

CG needs to be center between the motors, or at least as close as you can get it. It's helpful to have the flight controller there too, but it isn't critical.

[Derek]

I honestly don't know how I built this quad with the Naze32 NOT in the middle of the frame. It just makes sense to have it in the middle...same with the CG.

I'll work on it....

[Derek]

I've taken the action cam off the nose of the quad. Since my new Mobius has arrived, I had planned on using it instead of the action cam. The Naze32 is in the middle of the two motor arms, so it would be in the middle of the quad. I've been doing some testing, this weekend, and I'm not getting much forward progress. The quad does lift off the ground but it wants to roll to the right and it has a wicked rocking motion from nose to tail...pretty much like a see-saw. It will rock back and forth more and more each time and then becomes unflyable.

I recalibrated the accelerometer and the esc's. I'm pretty confident those are correct. I'm not real sure what else to do.

[KevG]

The roll to the right is classic vibration symptom, the rocking sounds pid related Derek

[Derek]

The roll to the right is classic vibration symptom, the rocking sounds pid related Derek

Ok, I'm thinking the vibs are coming from the motors. All 4 motors have been on my previous quads that have all crashed. Perhaps there is something bent that I'm not seeing. Perhaps I need to order some new motors. In fact, I've been tossing around the idea of ordering a new quad frame. I'm thinking of getting the affordable ZMR 250 quad. There is also a 250 "X" quad frame that I've seen recently. It looks real light weight and it's affordable, too.

I'll put some more thought into it and I'll get a new frame and motors ordered up. My Afro ESC's are new and they've been flashed with BLHeli. I've got two Naze boards and plenty of props (5" and 6"). All I really need is a new frame and motors.

[Derek]

As I was just sitting here, thinking more and more about it....I went ahead and ordered 4 new Sunnysky 2207-2100kv motors (the same that I have already) and I ordered the Carbon ZMR 250 frame. Since I ordered them today, I imagine the package will be here Wednesday or Thursday. I ordered them from www.buddyrc.com. They are only about 5-6 hours away. I've ordered from them many times and their shipping times are always fast.

Once the new ZMR gets here, I'll strip down the ECHO 290 and maybe I can just use the carbon fiber for other projects....it's hard to tell, lol.

Fair well to the ECHO 290.

[Stambo]

That ZMR frame was my first mini frame and is what I am still flying now.
Same sunnysky motors too.
What ESCs you gonna use Derek are they the small Afros?
That thing will scream on 4s.

[Derek]

I've seen many videos of people using the zmr frame and the price is nice at $19.99. The place that I ordered it from also sells replacement parts. I've gotten an email from them saying that the frame and motors have been shipped already. Awesome! The esc's that I have are 20amp Acro esc's, flashed with blheli.

[Graham Lawrie]

I have a ZMR Derek and it is solid:) only ever broke 1 arm after multiple crashes:)

[Derek]

Thanks Graham! Its good to hear another person talk highly about that frame. I should have it Wednesday or Thursday