[TheOtherCliff]

Because i know some things about magnetic fields except the beeper i don't believe the wires from the motors are the problem. Nothing else i close enough. But thanks again and i will try tomorrow to fly and get back with the results.

Standard LiPo alarms use small speakers that have real permanent magnets in them (not piezoelectric).  That is a real problem.  You can test it with a compass or by watching GCS scopes or PFD/HUD as you move one of these alarms close to and around the mag sensor being used.

[Johnnyboy030]

That is very high and is probably exactly this problem.  After ESC calibration you should do ESC neutral setting.  Most people find that about 1070us is a good value.  I recommend using about 20 higher than "good smooth low value" to help when the ESC gets warm and the timing changes.

I am a little confused. The neutral setting is when the motors are starting with the minium throttle apllied correct? No matter what i do the motors don't spin at any lower value. Can you give me specific instructions what to do?

[f5soh]

Esc calibration page

[Johnnyboy030]

Standard LiPo alarms use small speakers that have real permanent magnets in them (not piezoelectric).  That is a real problem.  You can test it with a compass or by watching GCS scopes or PFD/HUD as you move one of these alarms close to and around the mag sensor being used.

Do you believe that the alarm can also have negative effects on the other sensors of the cc3d? I mean the gyro, baro etc. I went again today to fly the quad (without GPS) but when i switched to auttitude hold i had very big differences again from the initial altitude when i activated the mode. Also it is important to say that it was a sunny day but with low temperature (~13C) and it was a little bit windy. The stupid thing is that i forgot to enable the logging so i could send the file to you. Next time i guess.

[f5soh]

Baro can be affected by sun light and propellers burst.
You may put some open-cell foam above the barometer sensor.

Some Revo or Sparky2 has issues with regulator (CC3D do not have baro sensor), introducing very big spikes to the pressure/barometric sensor.
Take a look here: Altitude Hold

Please do not quote all the previous posts and keep the thread easy to read.

[Johnnyboy030]

I bought the cc3d with a case and when i opened it i saw there was already foam applied to it. Also i put it under the first layer of the frame to protect it from the sun. Should i replace the foam with my own? I just can't understand whats going on with the attitude hold. It was working great and now it doesn't. The only thing i can think of is the thermal calibration. When i first started to fly the temperature was between 28~35 C and now is between 10~15. Can this cause the barometer change it's readings?

[TheOtherCliff]

To be clear, CC3D is old FC without baro and can't use GPS flight modes.  Chinese sellers have corrupted the name to mean everything so they can get people to look at ads.  "Revo" is a Revo, not a CC3D. 

If it already has dark foam over it then bright sun probably isn't the issue.  For baro and AltitudeHold/Vario, the next probable reason is prop blast as @f5soh said.

Generally, any amount of thermal calibration helps, not hurts, but there is an issue that you should redo gyro calibration after thermal calibration.  I doubt it causes your issue.

Does it fly well in Attitude mode with Attitude->Settings->AttiEstAlgo set to Basic (must remove GPS flight modes from switch setup to do this)?  If it flies well in Basic, but not INS13, then the problem is very probably a mag (not level) or baro (up and down) issue.  I would research this way to narrow it down.

Work your way up starting with Attitude mode in Basic, then Attitude with AltitudeVario (thrust mode at bottom of page) in Basic (take off in Attitude mode / Manual throttle), then Attitude / Manual throttle in INS13, then VelocityRoam in INS13 (take off in Attitude mode).

For anything mode that uses baro or mag (Altitude Hold/Vario thrust mode or GPS flight mode or basic mode with GPS Assist) it is required (highly highly highly recommended) to take off in Attitude mode with manual thrust.  It won't even arm in a GPS mode.

[f5soh]

There is no issue with gyro because there is no relation between vertical estimation / altitude hold and gyros.
Anyways Gyros are initialized / zeroed every time the board is armed if settings are keep as default.

Uncalibrated Accelerometers can add a little error to altitude estimation but not like you describe.
Thermal calibration helps for long time drift while the board warm.

Double check baro scope like displayed in wiki page linked above.
If stay within one meter, it should be fine.
If big jumps, you may need to fix the regulator like described in same wiki page.
This issue may be fixed/tested fist using Basic fusion algorithm, Attitude stabilization and AltitudeHold/AltitudeVario.

[TheOtherCliff]

I do thermal cal very carefully.  FC packed in a box with towels on top to press it to bottom of box to avoid motion.  Box sitting firmly on a stand and heated with a light bulb.  Temperature allowed to go to 65C+ because that is what it can get to inside quad dome in summer time.

This user seems to be trying to set up GPS flight modes.

Each time, after thermal cal, the gyro is a bit off.  I have to do gyro cal after thermal cal.  Picture (gyro quarter) shows slightly miscalibrated gyro after thermal cal.  The large square error is during the gyro cal.  After that you still see the error until you press Save.  So the beginning of the gyro 'scope' is after thermal cal (about 0.6 deg/sec error) and the end is after gyro cal and Save (more like zero error).

[Johnnyboy030]

First things first. I have bought the Revolution with integrated oplink from hobbyking. After the reset of the board i went today for flying. I only fly in Basic for now but through the setup i have activated the gps to main port and the mag to i2c, but i don't use them on flight. Also i added AltitudeHold and AltitudeVario as flight modes 2 and 3. The first flight mode is on Attitude and Manual Thrust. So when i tried today to fly the quad was good but not perfect. Then after a while i decided to switch to AltitudeHold to see how it behaves and again as the last time i had major differences at the height so i grounded it. The problem is that i am alone and i can't see at the same time both the laptop and the quad as it flies.
The second thing i want to tell you is that from my initial build of the quad i changed it a bit. The first build was with the FC as it is now and the ESC at the top layer of the frame. I believe that i maybe had the problem with the baro before but because of the presence of the ESC on top of the ESC maybe the ESC was absorbing the air currents generated from the props. I will try on some point to fly with smaller props, maybe 10', because those are 12' props and are really big.
About the capacitor on the board. Will i cause problem if i remove the capacitor anyway? Because on the wiki page says better without it that's why i am asking.
Finally can you please tell me how to enable the logging of the sensors because i tap the start logging but then nothing is being recorded.
Thank you in advance for all the tips both of you gave me so far.

[TheOtherCliff]

If your quad is very weak it needs more than 50% throttle stick to hover.  If it is very strong it needs less than 50% throttle stick to hover.  AltitudeVario always hovers at 50% stick.  Switching from manual to AltitudeVario does require changing the throttle stick for this reason.

You need to use correct props.  If 10 inch are correct then 12 inch are too big and that can cause strange problems.  If you just hover for a flight and afterward the motors are too hot to hold, your props are too big.

You must get prop blast off of the baro.  Some have used a piece of paper towel cardboard core to make a chimney for testing at least.

Test the baro altitude noise as discussed in the baro thread.  If you have about 1m or less of noise it is OK and I would leave the capacitor on it.

Tools -> StartLogging (and select a name and place for the log file) is all you need to do for logging.  Generally all the sensors you need will get logged this way.  Stop the logging when done.  Of course you need an OpLink RF connection or USB connection to get telemetry to log.

To play back, select "Logfile Replay" in the "Connections:" at lower right of GCS window.  Then press Connect and it will THEN ask for what file to play back.  At this point, everything in the GCS moves just like when the log file was recording.

During live or playback you can look at the Scopes page to see real time graphs of the data.  Enable Window->EditGadgetsMode and change the window panes to be what you want to see. Tools -> Options -> Scope is where you can add new things to view or change the parameters of the things you watch, things like the line represents 30 seconds or 30 minutes...

[Johnnyboy030]

My quad is powerful, i take off at about 25%-35% depending on the weather. Also i tried again to calibrate the motors using the video you provided but again my neutral speed was around 1190.
I undestand now how to replay the logs. I will attach two replay logs with my indoor tests. It is small flights and i haven't engaged any flight modes. But the curious thing as i was replaying the logs is that the baro keeps at zero. Even indoors shouldn't the baro had read at least some small difference between the ground and the flying altitude inside the house that was more or less 2 meters.

[Johnnyboy030]

theOtherCliff you were right. I removed the battery checker and then i calibrated the mags as shown in the video in librepilot wiki. After that i tried what you have said and i tested the checker by getting it closer and further from the mag and it is clear now that this was the problem. As i move it closer the error percentage was going up to 100% and when i move it to the location that was installed on the frame it was around 35%-45%.
I got so excited that i flew it indoor after activating the INS13 Indoor. It flew very well with little problems but i got injured during the flight. For some reason the drone reacted somewhat unexpected and was going straight to my neck but i put my hand and i have now a very nasty and deep cut to my middle finger. So deep that i lost a decent amount of blood and i did some stitches to stop the bleeding. So please tell everyone once again to stop do stupid things inside their homes.

To sum up i am happy enough about the resolution of the basic problem with the mag, but i need help to resolve the problems with the modes that are using the baro sensor and then i will proceed the gps modes outdoors of curse.

[TheOtherCliff]

Thank @f5soh about the lipo alarm speakers.  He was the one to show me about them when I was assuming they were piezoelectric buzzers.

I have never used INS13 Indoor although it should be fine.  I always use Basic or Outdoor.

Sorry about your finger.  I have been cut badly too and it isn't fun.

Look at baro scope.  You may have to make a baro scope in tools->options->scope.  Important to disable "everything baro" except for baro altitude.  Auto ranging that includes others will make range too large to see altitude changes.