“Sometimes, we need to add some seasoning to our life, so that you ll feel better and create more fun to prompt life become amazing. My colleagues and me always forget to close the door after our meeting, and there are too many valuables in the meet room. I think keep door closed is a good manner. So how to change this status? I have a idea now, both of us like listen to music, especially light music and classical music. The voice of theremin sounds deep but melodious. It always make me feel comfortable. Although we are engineer, we also enjoy life with massaging our ears. How about to make theremin by Arduino? It seems well if we could play the music with the process of closing the door. When we start to work, some of problems encountered, such as how to make the sound feel more comfortable and set the effective range and so on, these have been solved by modifying the program. Arduino is a easy but powerful tool, we complete finish this project as it cost just several hours.”