This repo provides the code and installation instructions for creating a Raspberry Pi based simple controller for ROS projects. My use case for this is to provide easy switching between motion planners and an emergency stop for a robot interaction study I am conducting. Although, this could be used in a myriad of other projects. This box simply reads some input from the GPIO (either a button or a rotary switch) and then publishes this onto ROS.
Additionally, I have included the specific products that I have used to create my version of this box. However, you should be fine to use whatever so long as you can plumb it up correctly