Cirus vs ZMR Multiwii boards

[kad]

I'm looking to pick up a Multiwii SE off of eBay and the two I see (mostly) being sold are the Cirus labeled and the ZMR labeled. I've seen a couple of threads on the Cirus, but nothing on the ZMR. Both are running about the same price, but most of the ZMR brand sellers seem to be including a FTDI programer. Does anyone have any experience with the ZMR boards? Are they better? worse? equal? to the Cirus?

-K

[Arf]

Never heard of ZMR are you sure you have that right?

Link please.

[kad]

Never heard of ZMR are you sure you have that right?

Link please.

http://www.ebay.com/itm/Newest-MWC-Mult ... 3cc5ee96db

Check the photos, it's on both sides of the board. About half the stock on eBay is this board.

-K

[Arf]

The color and writing looks like it was done by Crius. I would say it's an improved model by the same people. eg. it has a 328 on it where my Crius is only a 168 MPU. There is a new 40mm model of the Crius getting around too.

http://www.ebay.com.au/itm/NEW-Mini-Upg ... 3a74ac3786

[birdofplay]

I just received one of those boards from flying-xys .

My voluminous comments are at ...
viewtopic.php?f=8&t=1598&start=40#p16169

I'd have to say that at this moment I am Not Too Happy.

Bob
Northwest Cutout Service

[Arf]

I just received one of those boards from flying-xys .

My voluminous comments are at ...
viewtopic.php?f=8&t=1598&start=40#p16169

I'd have to say that at this moment I am Not Too Happy.

Bob
Northwest Cutout Service

Lol, you posted that in the Chinese IMU code development thread, nothing to do with Crius etc.


Your problem is the migration from KK to Multiwii, very little to do with board vendors, the software systems are not the same, and MultiWii is generally more sensitive to vibration as it's based on MEMS sensors that respond faster, also the calibration process is a lot more complicated than KK, way more parameters to adjust.

There is a big Crius thread on rcgroups http://www.rcgroups.com/forums/showthread.php?t=1551599 lots of good tips and pointer there.

Also see this PID tuning guide. http://www.rcgroups.com/forums/showthread.php?t=1375728


The basic steps are:

Get rid of vibration before you start. Balance motors and props, use double sided foam to mount the board, not rigid standoffs and screws.

Set PID all to zero, gradually increase P until the copter starts to wobble. Always calibrate gyros first, with acc and other sensors turned off. You should be able to get a good stable hover with just gyro and accelerometer. Completely forget about baro, magnetometer until you have achieved this.

[birdofplay]

Thanks for the reply and setting me straight !
BTW:
Had the Guide, did the balance, removed any extraneous metal that I could.
Removed ALL my LEDs and wiring.

Moments AFTER I posted I found this ...
https://docs.google.com/spreadsheet/ccc ... 5c1E#gid=0

It set me on a Better track.

I'm fairly happy with things after a multitude of settings changes and experimental flights.
It can actually be flown Back and forth in the back yard with HI G stops at either end
I'm going to wear out my TX off/on switch with all this experimenting. wheeew

My board is attached with Velcro !
It hangs on but is relatively loose at the same time.
I doubt if any harmonics could get thru it. But I've been wrong B4.

Level is much better and I can do pirouettes more comfortably now.
There is still a slight occasional wobble, which "feels" like its either hunting or an outlying reading/Noise was picked up.
I'm relatively happy with the level for now.

But Now the Baro or Alt Hold is HUNTING BAD ( when switched on )!
It starts OK but as soon as it is perturbed or whatever
it starts oscillate in Alt and never seems to settle.

With MAG I expected the YAW to be ROCK SOLID.
Two sensors working towards the same goal, YA know ?
It still wanders back and forth, even with the MAG ON !

Thanks again

Bob
Northwest Cutout Service

[Arf]

I tried velcro but it was no good, too loose. The best thing I have found is gyro gel tape
http://arkrc.com.au/products/K10457A-Al ... -Tape.html

Magnetometer gets interference like you wouldn't believe from power wires. Many threads on it.