[FlyGuy]

First, I would like to thank the members of the LibrePilot project for picking up the OpenPilot ball and running with it. I’m sure I can speak for others when I say I was extremely disappointed with the support of OpenPilot GCS especially when the wiki and support site was suddenly shut down without notice. Even the forums were closed to new members so we could not ask questions on setup and equipment issues. I searched the internet for months trying to find solutions to my issues and was on the verge of chucking the OP flight controller and starting over when I finally found the LibrePilot project. So thank you again for taking over and providing this much needed user support.

This brings me to my post. I have been struggling since October after purchasing a OpenPilot revolution flight controller and u-blox NEO-M8N GPS to get my Tarot TL-250A to perform Altitude Hold, Altitude Vario and Position Hold. My setup has been tuned for manual flight and flies well in manual mode. I have searched the internet for solutions and have gotten the Altitude Hold and Altitude Vario to work but it could use some fine tuning recommendations. The main issue I am having is with the GPS. I’ve configured the GPS, it has recognized up to 12 satellites and I have green alarms across the board (with the exception of the alarms associated with autonomous flight). I have configured the arming feature and the Revo will arm (the PFD display indicates armed and AUTOPILOT. The computer audibly says “armed” and the motors will spin on throttle up). When I disconnect the Revo from the GCS and try to arm the FC, I don’t get any armed LED indication on the FC and the motors will NOT spin on throttle up. Can someone PLEASE HELP!  I’ve been stuck on this for over a month and am unable to figure it out. Also if someone could recommend settings to enable a more stable flight during Altitude Hold and Altitude Vario I would appreciate any info on both topics.

Thank you for any help you can provide!

[f5soh]

Hi, welcome.

You need to find witch alarm locks the arming.
How did you set the arming setting ? Witch setting ?

[TheOtherCliff]

I would add that it helps to have telemetry for this and it is nice to watch the GPS trail when doing waypoint flight.

Also, I assume you are running LibrePilot v15.09

Mag is a hard thing to get right via USB and changes when the USB plug is close or not.  One guess has it that your mag is no longer green with USB unplugged.  I would suggest that you recalibrate your mag:
- keep it away from all metal and computers and house wiring as much as possible while calibrating.  No washing machines, no water heaters, no cars, computers as far away as possible.
- I've done it with a 3m/10ft USB cable and a remote mouse, but it's not optimal and shhhh don't tell anyone
- be aware that the calibration is recording all the time, so do not think that you can set it down on a metal cabinet between saves.
- before starting calibration, hold it up, away from stuff, click, rotate, click, rotate, etc. keep it about in the same place in space.

Minis and high powered quads are notorious for GPS mode problems when using the onboard mag.  A high powered mini may not be possible with onboard mag.  But you haven't got that far yet.  Those problems only happen when the motors are under high current flight loading and the too close wiring of a mini messes up the on board mag.  Do you have all your high current (battery to PDB, PDB to ESC, ESC to motor) cables twisted properly?  That won't keep you from arming, but it will cause bad problems if you try to fly it in any GPS mode.

[FlyGuy]

I use the pitch down setting to arm the revo. I will check the flashing LEDs on the revo and get back with the findings.

Thanks for your response and help!

[FlyGuy]

Still no luck determining why the revo will arm when connected to GCS but once you remove power (USB and flight battery) and then power up (reboot) the revo will not arm. Checking all alarms (green) and led status lights (before removing power). When not configured for GPS, I can determine the status of the board by the led flashes. When revo configured for GPS the leds are always the same (alternating red and blue). BTW, what do the flashing bars in the Data window mean? Does it mean the associated item is receiving data?

Been working on this for a month! About ready to look into buying a different flight controller!

Thanks again for any help you can provide.

[TheOtherCliff]

I'm confused.  Your issue

Can you arm with the sticks if you disable GPS, and use just Attitude mode on all positions of your flight switch?

I'm not recommending that you try it, but if you have, what does it do if you arm with GCS connected, and then disconnect GCS and fly?

To arm with GPS flight modes, you must use INS13 in Configuration -> Attitude -> Settings -> AttitudeEstimation
You must also set HomeLocation.  Easy way is to right click on the map and do Set Home Position (use 0 for the WGS84 popup if you don't know it).
You should arm and take off in Attitude mode and switch to some GPS mode when in the air.

Is your telemetry set up in some non standard way like OSD maybe (remove it and disable it for a test)?  Your hardware page should be stock, except for the GPS setup and RC receiver setup.

What RC receiver input type are you using? PWM?  SBus, ??

And you shouldn't be using Custom mixer.  That requires extra stuff that I am not familiar with.

[agileheliuk]

Sorry guys new here. I get a similar problem. When I enable GPS INS13 it knocks out all my gyro? and wont arm. I have managed to get it to get the gyro back up after a while sitting outside and it can see satellites ok. but then the gyro seems all over the place. and it will not arm.
I have tried different software, different PC, reflashed it... no joy. if I disable the GPS INS13 it works fine, I get GPS sat data ok. so a bit puzzeled there.  I have tryied different arm settings all the same.
 I Did try Tua Labs at first after following a link that said to use that as Open Pilot was dead, then I found out about Librapilot.. started using that. but had issues trying to get the firmware back.  I used the Resurrection firmware and it seems ok. (I did not do the SM pin short though!) but now instead of the nice red stamp in the firmware page I get a yellow triangle, I went back to OP GCS and flashed it in there and I get the nice red good stamp. but as soon as I go back to Librapilot, it wants me to upgrade the fw. and I get the yellow triangle again..... also in the settings page. under data - GPSExtendedStatus - Firmwaretag = lots of little box's?  no numbers or letters. is this correct?

[FlyGuy]

I am having difficulty getting my Tarot TL250A w/revo to take off level when it is configured for GPS (INS13). When the revo is configure for non-GPS flight (Basic Complimentary) it takes off level and flies fine in manual, altitude hold and altitude vario. When configured for GPS (I finally got the mag and accelerometer calibrated and I have a green alarm board), I try to take off in manual mode, motors 3 and 4 lift the back of quad so I cannot achieve level take off. I attempt to adjust the trim but still cannot get a level take off. I’ve attempted to manually compensate but still cannot reach level flight. I’ve recalibrated the neutral for the motors in GCS several times but still have the same issue.

I’ve attached 2 .uav files one is configured for GPS and the other is not.

Could someone please take a look at these and let me know if they see anything that would cause this flight problem?

The following is the equipment used for this build:
Frame: Tarot TL250A
FC: OpenPilot Revolution
Motors: Emax 1806 motors
ESC: Emax Simonk 12A
GPS: Ublox M8N
Transmitter/Receiver: Turnigy 9X

Thank you and I would appreciate any help anyone can provide.

[FlyGuy]

I can’t get my OpenPilot Revo to work in GPS mode with Ublox M8N to achieve Position Hold or Velocity Roam. The Revo works fine in Basic (Complimentary) but not configured for GPS. GPS functionality is why I bought the Revo in the first place. I have been working on different settings/configurations and calibrations for over a month and cannot get it to even fly as well as the Basic configuration. I have come to the conclusion that either the Revo is defective (not willing to risk purchasing another clone) or some functionality just did not work to begin with. I have submitted multiple questions and files for review to the forum for help but no one has been able to help me solved my issues. With that said, I think it is time to move on and find a flight controller that will give me the GPS functionality I looking for. Does anyone have experience with a good reliable GPS flight controller they could recommend?
I commend the LibrePilot group for resurrecting the support of OpenPilot products after the original OpenPilot support was abruptly shut off.
Thank you for any information or recommendations you can pass along.

[f5soh]

Some remarks:
- Why remove the default deadband that applies to sticks ?
- Motors should have the same neutral because calibrated same time.
- Do some tuning, i doubt the default PI value fit exactly your setup. (you only modified the "D" term value) = try Easytune
- Never change the trims in your radio.

I think the main issue is the Mag that can't work in a small setup like a 250 sized quad.
How is the Mag alarm while you start motors ?

If you don't have Oplink, connect by USB.
Maintain firmly your quad, put some throttle and look how is the Mag alarm.

[FlyGuy]

I finally was able to get the Revo to arm when not connected to the computer. First, you have to set the home location and then calibrate the accelerometer, magnetometer, board level and gryo. I did not perform the thermal calibration. I am able to arm the quad but am having difficulty getting my Tarot TL250A w/revo to take off level when it is configured for GPS (INS13). When the revo is configure for non-GPS flight (Basic Complimentary) it takes off level and flies fine in manual, altitude hold and altitude vario. When configured for GPS, I try to take off in manual mode, motors 3 and 4 lift the back of quad so much I cannot achieve level take off. I attempted to adjust the trim setting but still cannot get a level take off. I’ve attempted to manually compensate but still cannot reach level flight. I’ve recalibrated the neutral for the motors in GCS several times but still have the same issue.

I’ve attached 2 .uav files one is configured for GPS and the other is not.

Could someone please take a look at these and let me know if they see anything that would cause this flight problem? I starting to think the Revo is defective and will start looking for a different flight controller.

The following is the equipment used for this build:
Frame: Tarot TL250A
FC: OpenPilot Revolution
Motors: Emax 1806 motors
ESC: Emax Simonk 12A
GPS: Ublox M8N
Transmitter/Receiver: Turnigy 9X

Thank you and I would appreciate any help anyone can provide.

[FlyGuy]

Thank you for responding.

- I did not intentionally remove the default deadband for the sticks. Used Vehicle setup wizard. How do I restore defaults?
- Motor start and spin consistently at different values. That is why the neutral numbers are different.
- Not familiar with Easytune. Where can I find this? Is it part of the LibrePilot GCS software?
- Changing the radio trims was the last ditch effort to level out flight.

The Mag alarm flashes between orange and green when applying throttle to the motors.

Thanks again for your response. Was about to give up and start looking for a different model flight controller.

[f5soh]

The Mag alarm flashes between orange and green when applying throttle to the motors.

With props mounted ?

EasyTune is part of LibrePilot.
https://librepilot.atlassian.net/wiki/display/LPDOC/TxPID

[FlyGuy]

Mag alarm flashes between orange and green with props unmounted. Will monitor with props mounted and let you know.

Thanks for the EasyTune link. I just knew it as TxPID. I will enable it and check it out.

[f5soh]

No props, no current.
No current, no magnetic fields.

The bad thing is you may need props attached for better flight