Quad Derek's New ZMR250 FPV Racing Quad

Derek

Derek

Well-Known Member
I have a new ZMR250 FPV quad. I got it all built with these components:

4 - Sunnysky 2207-2100kv motors
4 - Afro 20amp esc's flashed with blheli
Acro Naze32
Spektrum satellite rx
6x4 HQ Bullnose props (also have some regular 6x4 HQ props)
Bluetooth module (not yet installed)
Mobius Actioncam
5.8ghz ImmersionRC vtx with VAS Dura-Spec 5.8ghz LHCP antenna
VAS 3 turn helical 5.8ghz LHCP antenna on the vrx
ImmersionRC UNO vrx
Fatshark Dominators

After setting up the Naze32 and calibrating the esc's, I went into the backyard for the first test hover. The ZMR250 sprung off the ground into a very nice hover, requiring very little stick input to hover in place. It's very stable and I was very happy to have this thing hover so easily. Then I tried a vertical punchout...hmmm, not so happy now. The quad yaws clockwise in a punchout and then stops yawing when I come back off the throttle. I get the quad back to a "tail in" orientation and try to punchout again.....it yaws clockwise again. Hmmm, set it down and unplug it.

I began thinking that "perhaps" the esc's didn't actually fully calibrate...kind of a "shot in the dark" but it's a thought. I go back to my computer, remove the props (safety first), and I get back into Cleanflight (latest stable version) and I calibrate the esc's again. Put the props back on and head back outside. Back into a nice stable hover, just as i saw before, and then try a punch out.....it yaws clockwise. Very odd!

Would any of you quad guys know how to resolve this unwanted yaw action on punchouts?
 
Tony

Tony

Staff member
I can't remember the setting, but there is one that will stop this behavior. Have you tried adjusting your PID gains at all? More specifically the P (proportional)? Try raising that up on the yaw (I think you can do it on the yaw...) and see if it stops that. Leave I and D at factory defaults for now.

And I know this is a stupid question, but you are using the exact same props with the exact same pitch and length, right?
 
Derek

Derek

Well-Known Member
I haven't changed any of the PID's. I'm not very knowledgeable at making changes yet. I don't fully understand what happens when I'd raise or lower a setting and I don't know how much to raise or lower them.

I spoke with a guy on a Facebook group and he suggested that I increase the rudder deadband in the CLI. I've done that. Now I'm trying to find my small glow sticks so that I can tape them to the quad so that I can see the darn thing so that I can go outside, in the dark lol, and test it out.

If there is any, one, thing that I've learned from you, Tony, is that there is no such thing as a stupid question, so I don't mind you asking about the props at all. Yes, the four props are the same (two 6x4.5R and two 6x4.5 props).
 
Tony

Tony

Staff member
Even with different props, the gyro should hold it.

The way you start programming the control board is by starting with P. I don't know if you are flying in Attitude mode, or Rate mode, I'm going to assume Attitude mode. With this mode, you only have P and I to worry about, There is no derivative. In rate mode, you have the full PID (proportional integral derivative).

You will start with the P in what ever mode you are flying (leave I and D (if in rate) at 0 for now)) and slowly raise the value by .2 at a time. So if you have a P setting of 2.5, then take it to 2.7 and try it again. Right now you are focusing on the Yaw, so ONLY adjust the Yaw P setting. Keep raising it until you get a wag (like a tail gyro with the gain too high) then back it down .2. This should set it perfectly. Then, do the exact same thing to the Pitch and Roll and you will have a fully dialed in quad.

Once you get done with that, we will get into fine tuning with I and D. But doing only P will get you VERY close.
 
Tony

Tony

Staff member
Dude, you are going to make me get my CC3D quad out and start playing with it... If this wind will ever die down lmao.
 
Derek

Derek

Well-Known Member
I'm gonna resize a few pics of my new quad and I'll share them in just a few minutes. I've had 3 other quads, prior to this one, and this one is the lightest that I've ever had. I'm super stoked about getting this thing to fly reliably and get some good FPV done.
 
Derek

Derek

Well-Known Member
Yeah man! This FPV stuff is awesome! I did the maiden flight of my HK Skyfun today with FPV onboard. Just a couple of trimming flights, but that's for another thread, lol, but I'll have my FPV 250 racer and an FPV Skyfun.

- - - Updated - - -

Here are two pics that I just took:

Quad Pic1.jpgQuad Pic2.jpg

Quad Pic1.jpg

Quad Pic2.jpg
 
Tony

Tony

Staff member
Looks exactly like mine (which I can't find the friggin props for!!! UGH) Except you are running the C lens on your mobius. Now we just need some onboard video! :biggrin1:
 
Derek

Derek

Well-Known Member
What quad do you have? I like the C lens on the Mobius.

As for the video....I was hoping to do that today but with the quad yawing on punchouts, that's just not acceptable. I have to work tomorrow night and Tuesday nights, so I won't get to mess with the quad much until Wednesday.
 
Tony

Tony

Staff member
It looked even better with a 600mw Tx, fatshark camera up front, mobius on it and something else that I"m forgetting lol. One of these days, I will have all of that back and I will be flying all over the US. Really need to get back up to Utah and fly up there and get some footage!!!
 
Derek

Derek

Well-Known Member
Yeah Rodney...these things are a good time when they are all set up properly. Just great fun! You can fly them around real slow and just enjoy the view or your can mash the throttle and really scream around. I'm hoping to get this yawing issue sorted so that I can get flying FPV with the quads again. I'm thinking that the yawing may be coming from vibrations. I'm going to try some 5x4 HQ props and see if the smaller props will reward me with solid punchouts.
 
Tony

Tony

Staff member
Well, I took my quad out to see if I can replicate the issue and I couldn't make it replicate. I did get video but the entire thing was out of frame. Hate not having a camera person.
 
Derek

Derek

Well-Known Member
Here is a bit of video of my ZMR250 quad yawing on punchouts. The punchouts are small because it will yaw all the way around if I continue to add power

ZMR250 FPV Quad Yaws Right On Punchout - YouTube

My setup is:

Naze32 flight controller
Spektrum Satellite Rx
Sunnysky 2207-2100kv motors
20amp Afro ESC's (flashed with blheli)
6x4 HQ props
3S 1550mah 45C Glacier Lipo

Motors and props are all going the right direction. This is the same component setup that I ran on my ECHO 290 FPV quad and that quad flew very well. The ECHO 290 quad was even 130grams heavier. I just find it really odd that the same setup on the ECHO 290 is failing on the ZMR.

I've even changed out the Naze32 and the yaw issue is still there. So, I'm guessing the issue isn't with the Naze32. I've swapped the motors around and the yaw issue is still there. I've tried different props.

Any ideas how to fix this yaw issue on punchouts???
 
Tony

Tony

Staff member
You say you have swapped the motors around? Did you take the right front and put it on the right rear and the same with the others (making the CW motors CCW)?

Have you tried setting up a new model in your Tx? The reason I ask is this almost looks like you have some yaw built into the mixing in the Tx.

Also, did you go up on your Yaw P gain?
 
Derek

Derek

Well-Known Member
Tony said:
You say you have swapped the motors around? Did you take the right front and put it on the right rear and the same with the others (making the CW motors CCW)?

Have you tried setting up a new model in your Tx? The reason I ask is this almost looks like you have some yaw built into the mixing in the Tx.

Also, did you go up on your Yaw P gain?
Click to expand...

Yes, when I moved the motors, I moved them to opposing corners...keeping the proper rotation.
Yes, this is a new model profile in my DX8....there should have never been any yaw mixing built in.
As for the upping the yaw P gain, no, I haven't, lol. Forgot. I'll give it a go after dinner. How much should I go up? 5 points...10 points.
 
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