Edit: Success - http://diydrones.com/profiles/blogs/it-works-fully-automated-parach...

I want to try this with my quad and see if and how it works.

Here's my waypoint list:

Basically takeoff to 6m (will actually take off the ground myself as AC v2.7.1 doesn't seem do the takeoff).

Then fly to a close waypoint at 10m alt, then to a further waypoint at 60m alt, loiter for 5 secs, release the chute, loiter for 5 secs, descend to an interim waypoint at 30m, descend further to a closer waypoint at 15m and RTL from there. This is in a fairly open area and the drop will be about 60-70m from the takeoff. May change the waypoint positions if there's a bit of wind.

Does that order & logic look about right?

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Doesn't work at all in the ArduCopter HIL simulation, which is where I actually want it.

The outputs for channels 5-8 are all zero and I can't get anything different.


I spend 45 min reading on how to trigger a servo to drop a chute and come to find out it was not working... same frustration. Hopefully a fix in in the works.... currently I am achieving this directly from the receiver

Has anybody got anywhere with this?

Started today, Constructed a simple parachute deployment system, using a servo as a release mechanism.
Working ok directly from Rx. So can now look into the code, see what is happening, but will need some help!

do_set_servo() is the appropriate command

mavcmd.xml. valid inputs:=
servo number (presumably referring to channel number)
pulse length. valid values for me is 935 to 2055 uS, so using 1000 to 2000uS. 2000uS= release position.

mission programming, writes to eeprom, and reads back so it is being recorded


static void do_set_servo()


    APM_RC.OutputCh(command_cond_queue.p1 - 1, command_cond_queue.alt);


That Suggests: The o/p channel is the standard APM RC out channel 5.

Connected and flown in a simple mission, servo remains at extreme end position (935uS)

Can any programmer shine some light?
Do we need to enable something?
How can we set servo prior to flight? (presumably auto will overide channel switch)

Graham, Did you get any movement at all?
Did you try using APM rc out channels?


Peter, I only get servo movement in Arduplane and then only when the point DO_SET_SERVO is reached in the mission, there is nothing to indicate before that point that the servo will work and the servo will be at (but not getting a PWM signal), it's last commanded position.

In ArduCopter nothing works.

I'll continue to delve into it, although the code is not clear at all!
It suggests that the output channels are the APM rc outs on the end of the board.
Looking at the standard config screen in mp, it appears that channels 5 to 8 are disabled by default,
but the enabling options are a defined list, no mention of servo's (or relays for that matter)
Think I'll repost this message on the MP forum see if John can explain the enabling options!

edit: Oh dear, we are already in the MP forum...

Perhaps John will read this and explain!

It might be worth having a look into the ArduPlane code as it seems that those channels are enabled there.

Perhaps Micheal Oborne can assist in setting a servo in mission planner!

Currently trying to exhaust all existing avenues...

Here is my attempt so far


hopefully part 2 will achieve a working flight, still would like to know if we are doing it wrong, or whether the code is non functional...

Peter, have you tried the HIL simulation at all? Saves masses of time for testing, I've clarified the wiki so it should make it a lot easier to setup and use.

ok I think your right Graham, I can spare an apm2 to HIL, have done it before for Arduplane, so should be able to get it set up quickly without problems.

Graham, what soft are you using?

I used xPlane, oh couple of years ago! I see that Flightgear is the only one recommended now, other than Jason's.

Downloading FlightGear atm...

Great work guys.

Watching the development of this function with interest.

Am interested in your thoughts about use of parachute to 'land' the machine. I guess I'm thinking in the eventuality of the machine getting out of shape (wrong way up) or heading off on its own mission .... could the operator manually trigger the parachute, power down the motors and hope for a gently landing..?


I need this feature.  What about a glider?  Do you guys think that a glider could be lifted off the ground and the glider could release itself once it hit the required altitude, regardless of speed or location? 

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