We are a team that is participating in a robotics contest. The name of that contest is First Lego League. After becoming the 8th team on Greece we will be participating in the global tournament of Lebanon on the 16th of June.
We have managed to create a machine witch replicates the concept of noise cancellation. The machine uses 2 speakers. One is connected to the sound hub normally (with the + input going to the + output etc) when the other speaker is connected in the opposite way.
When the 2 opposite sound waves of the speakers collide causing each other to be cancelled and the total noise produced by them to be reduced. This can be used in the international space station to help astronauts with the very annoying noise caused by the machines inside of the station.