I would like to request help for a possibly trivial, but I think somewhat important, issue.
I have a quite standard setup I think, a radiomaster boxer, radiomaster rp3 running expresslrs 3.5.1 on both sides. I setup mavlink as instructed on the expresslrs / arducopter site, and it works with mission planner which is excellent.
However, before I go fly, I wanted to test radio failsafe, and that does not work. It works when I use a channel to activate rtl with a switch, but not when I turn off the radio to simulate loss of signal. I am pretty sure this is an option I missed somewhere, but I cant find it.
I would like to ask if someone can point me to a possible solution.
Link setup details:
RCTX
Radiomaster Boxer
Packet rate: F1000
Telem ratio: 1:2
Switch mode: Hybrid
Link mode: MAVLink
Model Match: Off (ID:0)
3.5.1
RCRX
Radiomaster RP3
Protocol MAVLink
SBUS failsafe No Pulses
Target sysid 1
Source sysid 255
Ant mode Diversity
TLM mode MatchTX
Model Id Off
3.5.1 e24800
Arducopter
fc: holybro kakute v1.3
fw: rev 4.5.5
SerialX_Protocol: 2 ( mavlink 2)
RSSI_type 5
RC_Options: 8704 ( suppress crsf mode/rate messages for elrs systems, use 420kbaud for elrs support )
Hope someone can give advice on this, I’m not all that keen on flying without tested radio failsafe… and mavlink over elrs is very convenient I think.
while making the log file ( props off, system outdoor, arm & spin up, transmitter off ), I think RTL did work… the drone increased throttle, then decreased throttle, then stopped motors. That looks good to me
So RTL may work, but my testing by using mission planner and looking at the messages in the hud display may be the issue…
The flight mode field switches to ''RTL" while using a channel to switch to flightmode rtl, but I do not see a flightmode change when I switch off the transmitter… So perhaps that got me confused.
If the copter is disarmed, no failsafe will take place.
If the copter is armed but has landed, the copter will immediately disarm.
If the copter is armed in Stabilize or Acro modes, and the throttle input is at minimum, the copter will immediately disarm.
Otherwise, the copter will take the actions as configured in the parameters described below.
I was following that exact page for my setup, and was using it to test failsafe. At the end of the page there is a test paragraph for the low-throttle method, but no explicit test for the no-signal method.
I was attempting to do the same test structure using mission planners hud-screen, and that did not work, good to know the cause of this was on that exact page, but still had me puzzled for quite a while.
The post by Lupus above may be a good way to check if the no-signal method works, or perhaps an addition to the docs to detail the testing of the no-signal method?
