I’ve noticed a cool (and slightly concerning) trend in the maker community lately: DIY computerized model rocket launch controllers. Here are two examples:
- Phone Launch Controller – http://makezine.com/2014/07/17/smartphone-rocket-launcher/
- Arduino Launch Controller – http://arduinohandbook.wordpress.com/projects-16-30/28-rocket-launcher/
The cool part about this trend is the sudden interest and popularity of model rocketry (and hopefully by extension spaceflight) in the maker community (just listen to the excitement in the Phone Launch Controller maker’s video to see what I mean). I would love to be able to capitalize on this momentum (time and plan permitting).
The somewhat concerning aspect of this trend is the lack of adequate (or sometimes any) safety features. The primary safety feature I am referring to is the safety pin in a commercial launch controller like you would find in a controller from Estes. The safety pin is an integral part of the launch controller circuit, without the pin engaged, the controller cannot ignite the rocket motor.
From the video, it appears the Phone Launch Controller lacks anything like the safety pin (though I may have missed something and I would be happy to be wrong about this). And the Arduino Launch Controller does require two buttons to be pressed to confirm the launch command, but it does not appear to have any physical safety apparatus to prevent a software bug from triggering a launch.
I still have a few things I need to clear off my plate, but I might use some of my own time to look into what it would take to modify the Arduino Launch Controller to include a physical safety interlock (maybe a key switch in place of the safety pin). Thoughts? Anyone have an appropriate schematic for the launch controller circuitry including the safety pin?