"Prearm: Fence requires position"

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.

Everything looks good except the GeoFence, If “Type” is selected the “Arm: Fence requires position” is displayed when trying to arm.
If “Type” in GeoFence is disabled then i can arm the drone easily with no issues .
all arming Checks are active and looks OK.
what the "pos_horiz_abs off " in Red when the EKF Status is selected ?
LEDs on the GPS are flashing blue with GPS sat count =7 and Ready to arm is displayed
Thanks all for your inputs helping me finding a solution to this problem.

Are you doing this outside with clear view of the sky? 7 is low for a sat count.

What solution?

No I’m inside “basement”, sorry when “GeoFence Type” is selected I get Not Ready to Arm". If GeoFence is not selected everything looks good
“Solution” What i meant is the GeoFence issue.

Is this sarcasm or reason for a facepalm?

I’m answering to a question if I’m inside or outside ? Do I look like I’m joking?
When GeoFence is selected


and the EKF Status like this

I tried to Arm outside on a clear field with GeoFence selected it arm once, I can’t say on what condition since I don’t have crossfire telemetry yet, should be in in a week.

Well there’s your problem…

There is no other reason, I should be getting the Telemetry Module by next week, once installed I’ll do the test on a sunny calm day and will let you know the results. Thanks