Confused about FENCE_ACTION

Hi everyone. I’m inching towards the first flight of my first ArduCopter build. It’s a basic flamewheel 450 clone with a 3DR Pixhawk running ArudCopter 3.4.5. I’ve been looking through the parameters to make sure I understand the configured behavior of each one.

For FENCE_ACTION there’s “Report Only” or “RTL or Land”. If I pick “RTL or Land” (the default), which is it, RTL or Land? Seems like there’s a big difference there - I breach the fence and either the craft comes down at that location, or it does a RTL. How can I pick which it is? Or am I misunderstanding what this does?

Thank you.

If GPS position fixed, then Fence action execute RTL, if not GPS position -Land.

The fence doesn’t work without GPS.

http://ardupilot.org/copter/docs/ac2_simple_geofence.html

@Anthony_Short read the Wiki article provided by Matt, it should clear your doubts. I should add that in 3.4 we added a new feature that will try to avoid breaking the fence (AVOID_ENABLE, enabled by default) - it can still happen that you break it if you go fast enough and, in that case, the fence action will be activated.

Got it - thank you. I wasn’t aware of AVOID_ENABLE.