This principle is equivalent to triggering an infrared alarm, commonly seen in movies, except that the sound is music. To create a ladder that matched the piano keys, the stones used on the steps on site were custom made. Furthermore, the music of Piano Ladder is not static. The integrated control box is similar to a computer host and can be implanted with various music.
It is understood that the piano staircase is located in the connecting passage between Exit A of Moziqiao Station on Chengdu Metro Line 3 and the City Concert Hall. Its steps are made into the keyboard of a giant piano. When passengers pass by, the "musical stairs" will not only light up, but also emit different tones, just like playing a piano. The setting of the piano pedal injects vitality into the silent passage and brings joy to the passing citizens. The song will be performed as you step up/down. Each step has a corresponding circular hole, and the step closer to the wall has a built-in infrared device that emits rays. When the feet block infrared rays, the lights of the corresponding steps will light up and the corresponding music will sound. According to Liu Bin, the person in charge of the urban concert hall channel project of China Railway Fourth Bureau Group Company, the piano ladder mainly consists of three parts: infrared equipment, integrated control box and audio. In addition to built-in infrared equipment on both sides of the ladder, the walls also feature built-in audio and integrated control boxes. When people go up and down stairs, when the light emitted by the infrared device is blocked, the integrated control box will issue instructions to play the corresponding music, and the stereo will play different music according to the different infrared rays that are blocked. The opening of the passage has attracted many people to travel and check in. Some citizens took the subway three times instead to take their children to play. This setting is wonderful and can add a touch of fun to our ordinary and boring lives. But there are also risks. After all, the subway is a public facility with people coming and going every day. This setting will increase the flow of people. If the subway is turned into a tourist destination, such safety hazards need to be paid more attention to.