The goal of this project was to create a karaoke system with a Rubens' tube fire visualizer. Rubens' tubes have been around since 1905, so they are nothing new, but we wanted to see how we could bring it into the 21st century.
To make a Rubens' tube, you need to drill regularly spaced holes in a metal pipe. Propane feeds into the tube through a valve at one end and slowly leaks out of holes along the top of the pipe. This gas is then ignited, forming a line of standing flames. A speaker sealed to the other end of the tube emits sound waves into the pipe. When sound is played through the pipe, it vibrates the horizontal column of air. When you play a sound wave with a wavelength that's a multiple of the length of the tube, then you create a standing wave, creating a sine pattern in the fire. For our system, we connected the speaker to the audio output of a NI myDAQ device so we could play any sound we wanted from the computer.
Our karaoke program utilizes three NI myDAQ devices, connected as seen in the diagram to the right. Two myDAQ devices serve as audio in/out for each player, connecting to a microphone and set of headphones. The third myDAQ device takes in the song to be played and outputs the music to the speaker attached to the Rubens' tube. The myDAQ’s then connect to the computer via USB.
Check out the Software Overview.