How to control a remote launcher?

@Duds Hej! I hear from @tridge that you have been working on a remote launcher.

We’re building a remote launcher prototype. It will look something like this:

I would like to ask for your (or anyone’s) advice on how to control the launcher. This thing will be fully remote so RC is not an option. I see three principal ways:

  1. Give the launcher it’s own connection, possibly over MAVLink, a little bit like an Antenna Tracker. It would then have to be connected separately to a GCS, with all the GCS integration issues that that would entail.

  2. Make the launcher a slave to the plane, by dedicating one or more servo channels on the plane to make the launcher prepare, cancel or launch the plane, and possibly to control it in additional ways. You would still need to be able to control the servos from the GCS. Like so:

  3. Control the launcher in a fully separate way, which would be a little bit impractical since the user would then have to interact with another app besides the GCS.

I would appreciate any suggestions, ideas or helpful links!

Sorry I didn’t see your message until now.

The way I do it is with a servo operated bungee release mechanism. The mechanism is connected to an auxiliary channel on the flight controller with an extension cable hot glued through the aircraft body. I set up the bungee then plug in the aircraft. @tridge has set up automation on the flight controller that sets the bungee release servo to 1200 own (the release pulse width) the bungee release and the aircraft launches pulling the servo lead loose from the extension hot glued to the aircraft. It’s really simple and it works. The idea came from the West Coast UAV guys they have the same setup. Here’s a link to my bungee release thing

Just a PS @tridge has also used a GCS waypoint to set the aux channel to 1200pwm. The very first waypoint is launch. For convenience @tridge wrote a “release” command into mavproxy. He just types release when I’m ready to test and a Mavlink command sets aux channel to 1200pwm.

Hej, and thanks a lot!

Please extend my greetings to your barbecue guests. I’m so grateful for all the good work. Hope you have blast!

Fredrik Falkman


Swedish Sea Rescue Society
Talattagatan 24; 426 76 Västra Frölunda
ssrs.se first-rescue.org surtsey.org

Twitter @fredrikfalkman
Skype fredrikfalkman
Cell +46-705-280058

Se om du passar för världens viktigaste extrajobb – frivillig sjöräddare! Läs mer och ansök på vår hemsida. Och dela gärna filmen så att fler får chansen. Se filmen här!

Hej, thanks I do a pretty mean lo and slow American style bbq! Smoked lamb sliders tomorrow night.

I just watched the video for some reason it doesn’t play for me in the discuss. I really think your concept is a good candidate for electromagnetic launch. Probably the concept is still the same an umbilical from the aircraft to the launcher keeps the aircraft batteries topped off ready for emergency and flight controller triggers launcher. Then electromagnetic rail accelerates aircraft to flight speed. At flight speed and n seconds flight controller switches motor on.