It looks like an ordinary toolbox, but when you open up the Arduino Launch Control System, you’ll find a safe method for triggering model rocket launches. The system uses two separate power supplies. Both must be on for a successful launch and one requires a key. To trigger a 10-second countdown, the operator must hold down two buttons. Releasing either button will stop the countdown.
Besides safety, the controller tracks mission elapsed time and can read weather information from a few sensors. A good-looking build and we like the idea of building inside a toolbox for this sort of thing.
Towards the end of the post, there are some ideas for improving the build, like using a consolidated weather sensor, using a larger screen, and a bigger, more capable controller. It seems like more I/O would be useful,
Model rocketry isn’t as rigorous as launching a crew, but there were a few things that could improve the overall system safety. For example, the launch buttons could provide both normally open and normally closed contacts to guard against switch failure. In other words, if you see both inputs from one switch on or off for more than a tiny moment during switching, you can assume the switch has failed and put the system in a fail-safe mode. Of course, a switch failure in the off position isn’t a hazard, just an inconvenience. But a switch failure in the active position could allow an inadvertent launch. Granted, it would require something jamming the remaining switch for the entire 10-second countdown, but still. Arduinos are pretty reliable, but for a real rocket system, you’d probably have redundancy, and the software would do periodic checks to guard against things like memory corruption. For example, NASA has a relatively succinct list of requirements. But some of this is overkill for a model rocket launcher.