We are working on the electronics for a hands-on museum exhibit that tests reaction time and shows how you can improve their reaction time through practice. The main components of the control unit are a BeagleBone Black, an 8-Channel Relay Board (to control a set of race track staging lights), and a custom-made protoboard with resistors and screw terminals (that take input from the start buttons and gas pedals). The exhibit consists of three race cars. Each car has a start button and a gas pedal. When someone presses a start button, then a set of large staging lights count down Ready, 3, 2, 1, Go! The staging lights are similar to what you would see at a drag racing track. The system then measures the time it takes each driver to press his/her gas pedal. The results are displayed on a large monitor (connected to the BBB’s HDMI port) that everyone can see. If anyone presses his/her pedal too early, then the “Too Early!” light goes on and the screen indicates that it was a false start. The system also includes appropriately-timed drag racing sound effects output through the BBB’s HDMI port to an amplifier and set of speakers. Here is a picture of the control board we made. It will go inside a clear acrylic box to protect it. This is a Rev C BeagleBone Black running Debian Linux. The custom software is written in Python.
If these are real bulbs and not LED bulbs that will be cycled many thousands of times, do you guys know about keeping a trickle charge through the filament to keep it warmed up? Heating and cooling the filament in one of the items that leads to premature bulb failure. Often, when these configurations are driven with PWM, the duty cycle is just turned down to a level that not much light is produced but the filament is still being excited at the same frequency to keep it warm. If using an on / off control then a parallel circuit to bleed a small current through them can be used. Just something learned the hard way with a light show project 30 years ago in high school that I thought to pass along… If the bulbs are LED bulbs, then this is not an issue. -Hope it helps…