While their popularity seems to be waning as LCD and OLED TVs grow in size and shrink in price, projectors can still be a good choice for home theaters. They can give you a screen bigger than any TV on the consumer market and at a lower price than large TVs. But if you get a projector for your home theater, you’re going to need a way to mount it. To keep his home theater projector out of the way when it isn’t in use, Sam Baker built this scissor lift mounting system.
A scissor lift was a good choice for this application, because it can be made very compact and still quite rigid. A winch-style cable mechanism would have been a bit more compact and simpler, but wouldn’t have kept the projector from swaying — something that would surely ruin the cinema experience. A scissor lift like this one uses the power of parallel linkages to translate short, high-torque movement into long actuation. It keeps the projector up close to the ceiling most of the time, but then allows it to drop down to the proper height when it is time to watch a movie.
The mechanical parts for the scissor lift (including the lead screw) and the enclosure were all 3D-printed. A stepper motor turns the scissor lift’s lead screw and an Arduino Nano Every board controls that motor through a small driver board. A limit switch at each end keeps the motor from turning the lead screw too far. An infrared receiver connects to the Arduino, which lets it look for a specific code coming from an infrared remote. When it sees that code, the Arduino drops the projector down into place so Baker can start a movie.
Read more about this on: Arduino Blog