This creation will use a fake wall to create a room under my stairs. The door to this room will be hidden, and open/close by way of a motor when the IR signal is received.

This is still in the planning stages. An arduino will reciever the IR signal and trigger a brushless motor to drive using the servo library to control the esc. A four bar mechanism will drive the door back and forth through 90 degrees of rotation for each full rotation of the drive gear. The drive gear will be 3d printed with bumps on one side, offset 90 degrees from the connection point for the drive rod. When one of these bumps triggers a limit switch, the motor will be stopped and the door will be in the fully opened or fully closed state. 

The motor will be geared down heavily since the motor I have are all designed for high speeds and low torque. Gearing will be accomplished with lego gears that I have hanging around already.