"Prearm: Fence requires position"

You might be on to something here. I just checked my Yaapu (page 2) page on my Taranis X9D+ and I see “no telemetry!” and all information is not being received. I don’t know what could have changed this, since it has always been working fine, but looks like I should reinstall the latest version of Yaapu (mine is 3 years installed) and see if that solves things. Strange it stopped working.

For some reason, my SERIAL2_PROTOCOL had gotten changed to “2.” I was not discovering any sensors other than FLVSS and RSSI. Changing SERIAL2_PROTOCOL to “10” fixed my Yaapu. Now I get my screen 2 and see the same prearm warnings I see in Mission Planner:

“Prearm: Mount not healthy”
“Prearm: Safety switch”
“Prearm: Fence requires position”
“Prearm Check FS_THR_VALUE”

Nice, now fix it one by one.
To fix the “Fence requires position” all you need to do is wait for GPS lock.

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This was the solution. I had to recalibrate my copter, because I was not getting a gps lock. Thanks for pointing it out.

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And have you also fixed the other 3?

Yes.

-This was due to my earlier experimenting with trying to install a Gremsy gimbal and having set my
type in Gimbal Settings in a previous firmware. Changing the value to “0” as sfacta suggested solved it.

-For some reason, my Taranis X9D+ controller must bounce below 975. Lowering my FS_THR_VALUE to 910 works.

-This is normal and only because I did not depress the safety switch.

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Nice man! Great job! Keep pushing!

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So now I am still getting “Prearm: Fence requires position” even though it seems as though I have a 3d fix. Here’s the Mission Planner warning, note my GPS status. I’m using two blended gps’s. I don’t understand why when I started using the two blended, the first gps always shows as “3d dgps”


instead of “3d fix” What does “3d dgps” mean?

It’s an enhancement enabled by Sbas. So potentially a better positional fix.

How do I get a “position?” I would think that is referring to gps position, which I would think 3D dgps means I have already. I must not be understanding what a position means to Mission Planner, or why I am not getting one.

The map screen on MP will show the number of satellites and the HDOP. The parameter GPS_HDOP_GOOD will tell you what you should have. I think the default is 1.4 (140 in the parameter). Don’t change that. Just have a look so you know what to expect. It’s not just about having a fix, it’s about having a good enough fix. More satellites can be good but isn’t always better.

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Hello,
Have you ever fix the FENCE_TYPE, Because On the GeoFence tab, the Type field still showing blank, while in the Full Parameter list FENCE_TYPE is set to 7 and when trying to arm the drone, I get the “arm: Fence requires position” I using the the Arducopter V4.4.4.
Thanks

wait longer. The EKF has not established enough of a position yet.

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Thanks I’ll try and let you know, Thanks

Don’t he fooled by the “GPS 3D Fix” message in Mission Planner. That does not mean it has sufficient positional information for some Pre Arm situations.

Then how do we know that EKF has established enough info of a position other then the “GPS 3D fix”

Activate all arming checks and activate fence. After that you can only arm if GPS is OK. This is a standard and recommended best practice. Basically you test it by arming the vehicle.

Once again, all that is on the Methodically configure and tune ArduCopter Blog post.

If you have telemetry then wait for these (EKF3) messages:
GPS

If you don’t have telemetry then just wait… It won’t Arm until it’s ready as you have discovered.

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Yes, sorry I forgot about the “EKF3 IMUx is using GPS” status text messages.

LEDs on the GPS will start flashing slowly in green.

MP will say Ready to Arm.

If you have a beeper some configurations will give you a “happy” (ascending) sounding tone.