Toilet Bowl effect

[Explorocam]

I am getting toilet bowl effect in Attitude and GPS fail safe (mainly fail safe). I have the Naza box facing forward, but I was less careful with the way I mounted the GPS disk.

I would love some help as I am used to using the OpenPilot CC board, but I have only had the Naza up and flying for two days. Any ideas to why I'm getting this? Plus I would love to see some tutorials on what it all means. I read parts of the manual but I was not a diligent as I could have been.

Thanks.

 

[andrewgcriag]

compass offset/declination. google for your location, search here and aim the compass accordinly. worked for me

 

[Bella7821]

http://www.rcgroups.com/forums/showthread.php?t=1666903
Look for the gouge list in the above thread

 

[Roger Ramjet]

I initially got a similar result with my NAZA (DJI F450). As it turns out, I observed an increasing clockwise toilet bowl rotation to the point were I had to regain control of the ship. Experimentation with GPS antenna orientation showed a net improvement with a 25 degrees (approx) offset to the left of centerline. An offset to the right of centerline made it worst. Make sure your settings with respect to positionning of GPS antenna is properly filled out on the software page and that the antenna is not closer than 10 cm of any motors. I initially tested various positionning with velcro before final fixation. I expect that a RIGHT offset is required for ANTICLOCKWISE rotation and LEFT correction for CLOCKWISE rotation. This is, off course, in North America as we both are. Hoping this will help.

 

[VINHEX]

Wouldn't it be so nice if the offset could be done in the setup rather than twisting the GPS... Maybe it's because I'm a coder.. LOL

 

[Roger Ramjet]

I suspect that there is a slight discrepancy between the alignment of the red arrow reference mark on the outside casing of the GPS antenna and the magnetic sensing probe of the NAZA controller. This causes a signal error and the toilet bowl effet is the NAZA controller attempting to solve this offset. As you experiment with antenna orientation and find the heading that aligns both the GPS antenna and NAZA internal magnetic sensor, all become magic and the Quad become very stable. That worked for me.

 

[mailman35]

Wouldn't it be so nice if the offset could be done in the setup rather than twisting the GPS... Maybe it's because I'm a coder.. LOL

if that was the case then the assistant would have alot better user configurable options.

how about some decompling and reverse engineering the serial protocol thats used to talk to the FC

 

[VINHEX]

They must be able to provide this, can't be that hard. Just sent email suggesting about offset. Will see what they say.. possible the usual "Please contact supplier" LOL Must some auto-reply LOL

Maybe it will come..

 

[mailman35]

or like the fff bug, the unit is not meant for this u are voiding warranty

 

[VINHEX]

Lol I'm doing it just suggesting it would be a good function wouldn't know where to start.. I've emailed Dji to see if they would be adding it.

 

[Explorocam]

New Problem

OK,


I made sure the GPS is facing in the right direction and calculate the X,Y,Z for placing the GPS. But now the quad is very slow to react in a little bit of wind and wobbles all over the place. Kind of a slow Oscilation. I'm running the Naza + GPS on a DJI RTF F550.

Here is a screenshot of my settings.
View attachment 5503

Aux switch #1 is set to my remote gains and Aux Switch @2 is set to Intelegent Orientation Control.

 

[Bella7821]

View attachment 5504

This should answer all questions about the NAZA/GPS and get you flying

 

[Explorocam]

Thanks fore the Gouge.

The thing is, I didn't change my gains. All I did was move Aux 2 from remote gains to Intelligent Orientation Control, I left Aux 1 for remote gains. (previously, I had both Aux 1 & 2 on remote gains; made sense to only use one switch for remote gains so I could free up Aux 2 for Intelligent Orientation Control)

I didn't change any of the gains though, and prior to the change the F550 was supper stable and snappy. I'm really not sure what I did.

 

[Explorocam]

Here's another question.

Should I have Basic Gain and Attitude Gain assigned to the same Remote Switch?

 

[Bella7821]

Here's another question.

Should I have Basic Gain and Attitude Gain assigned to the same Remote Switch?

No you shouldn't.
You should get it flying pretty steady with the basic gains, then INH them and you never have to use them again unless you add or remove weight. Then have the remote knob to adjust your Attitude gains.
At least that's how I have mine set up and my NAZA/GPS works absolutely perfect.

 

[Explorocam]

That make a ton of sense.

As I remember from the the OpenPilot, Basic Gain (Kp) is the gain for stabilization and Attitude (Ki) is the gain for stick following.

Must have take the settings off of Default and made them really low. Plus I had the same switch for Basic and Attitude so they were move together rather than independently.

I'll keep tune and let you know.

 

[Explorocam]

Everyone's advice has been gold.
It's getting much better now and I'll continue to rase the gain until I get ocsilation and then back it off just a little.

I have found something a little perplexing though and I may have missed it in the manual.
When I switch to Altitude hold the quad slowly lowers back down to about 10-12 inches off the ground and when I switch back to manual it raises back up. It seems to me that the Naza is recording this low altitude somehow, but I don't know how. Does anyone know what I might be doing wrong?

 

[chinwai]

if your toilet bowl effect is going clockwise (right rotation) remount your gps 2-3 degrees to your left and if its going counterclockwise (left rotation) remount your gps 2-3 degrees to the right. also make sure that you're gps mounting location is accurate (xyz axis). hope this help... happy flying...:tennis:

 

[Explorocam]

Thanks Chinwai,

I tried rotating the GPS ever so slightly and raised the Attitude gain slightly and now it seems to hold a position quite well. Thank you so much for the help. Tomorrow I'll add the landing gear/camera gimbal and tune it for the added weight. I should be doing FPV with this frame in no time.

 

[Bella7821]

Easiest way to get it not to toilet bowl is to go forward about 50ft and turn the GPS the opposite direction of the drift then re-calibrate with nothing in your pockets. Keep doing that until it will go about 50ft in pretty close to a straight line and your good.
Mine hovers absolutely in the exact spot, it only goes up and down and side to side a few inches. Down the street it drifts about 4ft after 50ft or so but I'm totally fine with that, just as long as I can hover in one spot.
I even ran a full battery (9 minutes on my F450) and it stayed in the same spot. I think mine NAZA/GPS works about the best it can get since the tolerance of the NAZA is several feet vertically and horizontally.