f5soh

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Re: GPS only seeing 6 satellites?
« Reply #15 on: November 07, 2016, 03:04:13 pm »
The method you used for auxMag mount only alter the AuxMag rotation, not the calibration.
The 3 bars should always return to 0, whatever the frame orientation. If still to 1 or 2 this mean a bad AuxMag orientation.
Of course the auxMag orientation should not move while flying

The scales from your config file are not consistent:
Code: [Select]
1.13847804 | 1.08568275 | 1.24294817This highlight most of the time a not perfect calibration where DJI clone should report something around 1.2 if i remember right.

jtrout19

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Re: GPS only seeing 6 satellites?
« Reply #16 on: November 07, 2016, 03:13:26 pm »
OK it is done and with pitch-roll-yaw set to zero blue bars are X axis 0 Y axis -1 Z axis 0

The pitching is almost completely gone. You can still see it but barely. Like it probably moves the distance of a couple pixles. SO definitely alot better.

New config file. So how do I get rid of the one -1 on my Y axis. I can get rid of by putting a value of 5 into pitch, should I do that or does the -1 still show that I did something wrong.


f5soh

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Re: GPS only seeing 6 satellites?
« Reply #17 on: November 07, 2016, 03:25:11 pm »
The -1 on Y axis still whatever the frame orientation ? facing down, up, etc ?
Still asymmetric scales in your last config file.

jtrout19

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Re: GPS only seeing 6 satellites?
« Reply #18 on: November 07, 2016, 04:04:13 pm »
Im not sure what you mean by that.  But the gps unit is mounted above everything on a mast. The mag chip is on the bottom of the board so the top of the mag points down. There is an arrow on my gps casing indicating the forward position. Unfortunately i had to go to work so i will revisit everything tonight. .
Those values you are looking at should all be the same number or close to it? If so where do you find them numbers?

f5soh

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Re: GPS only seeing 6 satellites?
« Reply #19 on: November 07, 2016, 05:04:46 pm »
Quote
Those values you are looking at should all be the same number or close to it? If so where do you find them numbers?

The scale numbers, are a part of a result calibration with Biases.
You can see all those numbers in the UAVOBrowser > AuxMagSettings and another place for the onboard mag (use search field at top)

Should be almost close, not 1.24 < > 1.08

I talk about the 3 bars values while moving the frame

jtrout19

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Re: GPS only seeing 6 satellites?
« Reply #20 on: November 07, 2016, 05:26:37 pm »
When moving the frame i will get jumps but small ones bars move 3 or 4 points and then settle back to. The original values of 0, -1, 0

Re: GPS only seeing 6 satellites?
« Reply #21 on: November 07, 2016, 09:25:38 pm »
The numbers will change a little when it is moving (rotating), but should come back to 0,0,0 when stopped at any bank angle.

That single -1 is not so bad.  Your GPS/mag is not _exactly_ aligned to your FC.  Fix it if you can (adjust mag rotation on same page), but if not, it should be OK.

jtrout19

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Re: GPS only seeing 6 satellites?
« Reply #22 on: November 07, 2016, 09:37:39 pm »
Thats what i was gonna do. If i use a small number like 5 or so then all bars are zeros and and return to zero in all posistions. But i still get the rocking in flight data tab of gcs when quad is not flying. And then if i try to fly it the quad oscillates but only in a gps mode. I did the calibrate about 20 yards from anything metal out in a cornfield. Is that good enough or do i need to go farther? I am still gonna try it again to try and get number correct that F5soh is talking about.

Re: GPS only seeing 6 satellites?
« Reply #23 on: November 08, 2016, 07:29:27 pm »
Your issues are probably not caused by only seeing 6 sats.  Even if your GPS only gets USA satellites you should still get 7 or 8 when outdoors and away from trees and buildings, nothing overhead and not even located next to something tall.  For best reception, tall things should be far enough away that they are lets say no more than 30 degrees above the horizon.

A small amount of rocking (a few degrees) in flight data tab is normal, but if it is flipping upside down and moving a lot it is a symptom that you are using an aux mag and AuxMagSettings.BoardRotation is not set correctly.
https://librepilot.atlassian.net/wiki/display/LPDOC/Aux+Mag+Setup+and+Calibration

Oscillation in GPS flight modes are an ongoing issue.  Two kinds:
- a quick oscillation (less than 1 second per oscillation, like PIDs too high in Attitude mode that comes and goes depending on which direction the quad is pointed)
- a slow oscillation (about 4 seconds per oscillation with movement in the east-west direction)

This thread discusses both issues
https://forum.librepilot.org/index.php?topic=382.0
« Last Edit: November 09, 2016, 04:09:35 pm by TheOtherCliff »

jtrout19

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Re: GPS only seeing 6 satellites?
« Reply #24 on: November 08, 2016, 08:40:37 pm »
I am going to take a comprehensive video of everything either tonight or tomorrow.  Thanks for all your guys help. I really do appreciate it. I own three revos as of now and absolutely love them. There is another mode that you can set complimetary+mag. Quad flies great and i have no issues in that mode. It is only when i switch to anything with gps. Occasionally i will get 7 satellites but no more. Ive gotten it to maintain 6 at this point. I want to mention that i have everyting ran through an arduino so i can get gps and mag data through on cable other port is taken by sbus. I am suspect of that causing my issue but wont know for sure until my sbus to cppm converter arrives
« Last Edit: November 08, 2016, 09:09:25 pm by jtrout19 »

jtrout19

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Re: GPS only seeing 6 satellites?
« Reply #25 on: November 09, 2016, 03:55:32 am »
OK so I just re did my mag calibration. I took off any metal I was wearing even my wedding ring. I walked a 1/4 mile into the corn field. Had my wife stay back at the house with the laptop. Did the calibration dance and these are the value that I came up with after doing it.

[1.11482167,1.08047616,1.20694065] You would still call these values asymmetrical. I have done everything right at this point. Module is mounted a good 6 inches above anything at all and my high power lines are lower than that. I have twisted all my cables. I am at a loss and getting very frustrated at this point. Only thing I have left is to take the arduino module out and connect mag through I2C and see if that works.

jtrout19

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Re: GPS only seeing 6 satellites?
« Reply #26 on: November 09, 2016, 05:19:40 am »
Ok well I disconnected the ardiuno and hooked everything back up with AUXMAG running through I2C and GPS running through Mainport. I cannot get my FC to read the GPS now.......Not sure what is going on, I am thinking maybe it is going to keep the DJI config until I leave it disconnected for a while. So that is what I am going to do.

I will say the AuXMAG is now reading a whole lot different than it was so we will see tomorrow morning i guess.


So i just did a quick calibration in my house....I know its a no no and I am going to do a proper one but I wanted to see my numbers and here they are

0.92088962,0.89249212,1.02140617

A lot better than the others. I bet it would be perfect if I did it outside.

My thought now is why did the arduino cause issues?
« Last Edit: November 09, 2016, 05:32:23 am by jtrout19 »

Re: GPS only seeing 6 satellites?
« Reply #27 on: November 09, 2016, 04:28:16 pm »
I was about to add more causes of low satellite count and that is any transmitter in the aircraft that might be bleeding through to GPS frequencies or noise on the power supply.

FPV transmitters can cause GPS issues this way.  The main USA GPS frequency is in the 1.5ghz range and a 1.3ghz FPV transmitter might cause some problems if the transmitter/antenna was mounted too closely to the GPS.

I don't know what version you are running.  I'm assuming 16.09RCsomething.  There was an issue with mag calibration at one point and one work around was to set the calibration data to default before doing the mag calibration.  So many things doing on, I don't recall if this is officially fixed in an RC yet.

Go into System -> Settings -> AuxMagSettings and set:
mag_bias to 0 0 0
and
mag_transform to 1 0 0   0 1 0   0 0 1

and do the same in RevoCalibration, then do the mag calibration.

Of course this has nothing to do with the GPS satellite count...

jtrout19

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Re: GPS only seeing 6 satellites?
« Reply #28 on: November 09, 2016, 05:07:52 pm »
I am running 16.09rc2 and fpv runs on 5.8ghz, control 2.4ghz and of course oplink at 433mhz. I cant get the fc to connect to the gps now. I removed the arduino module gps unit powers up and flashes blue light for satellite fix. But fc not reading data. Mag works great though over i2c. I did change protocol back to ublox instead of dji and and swapped rx and tx wires with not luck. Im prolly gonna buy naza clone from banggood for 22 dollars us.

jtrout19

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Re: GPS only seeing 6 satellites?
« Reply #29 on: November 13, 2016, 05:33:48 am »
Alrighty guys, Finally got my Sbus to CPPM converter in. So I started from scratch and reset everything. Got the quad flying really good with autotune. Then setup GPS and I2C AUXMAG. Gps works much better now. Constantly have 7 sat lock.

Went out to calibrate mag tonight. Its getting cold up here so I had my wife help me. She sat inside on the laptop connected to quad through OPlink and I went outside. Did the calibration dance. Saved everything set up VelocityRoam and PositionHold flight modes. First tried Velocity roam Quad had a hard time holding altitude at hover as well as with movement. Position hold was a little better. Quad still had difficult time mainting altitude it would dip down and then over shoot. In both modes the thing barely wobbled. I did have a small bit of yaw drift to the left in position hold.

Here are my numbers

.889801  .859264   .960515

f5soh---I assume you are going to tell me that the calibration is a little off being that the last number is over a tenth of a value higher? I am going to perform other calibrations and then redo the mag calibration. Since it is getting cold I am going to go ahead and do the thermal calibration as well.

I thought I read somewhere about there being PID's for GPS that were separate from the inner and outer loops? If there is how do you go about tuning those values? Is there a wiki page available? Couldn't find one.

One last thing is there anything else I need to look at or do that I have not mentioned here?

Thanks for the help guys!