The encoder is a motor that controls the automatic opening and closing of the elevator door. We often look at the opening and closing of the elevator, we know that there is a delicate and precise control behind it. The timing of the opening of the elevator doors and the timing of the final closing are very accurate. In the process of opening the elevator door, the operation of the elevator door can be accelerated, and the realization time is shortened. Through the encoder to correctly grasp the motor's movement and control it, the silky smooth movement can be realized.