3.3Trash Bag Seal DesignIn the design of automatic sealing of the garbage bag, use an ultrasonic sensor to detect whether the garbage bag is full. This method has the characteristics of simple principle and low cost. The bag sealing technology uses heating and melting technology. The melting and adhesion method is a very effective and convenient method of bag sealing. In order to improve the efficiency, nickel-chromium resistance wire was selected, which can rise to higher temperature in a short time [7]. When the bag sealing device is energized, a stepper motor installed on the device drives a synchronous belt pulley to drive the belt to move the horizontal plate equipped with the electric heating wire forward and clamp the garbage bag with a fixed end. Then the heater heats the heating wire, melts the plastic bag and sticks it to seal the bag. In addition, a heat insulation strip is fixed at the other end, which prevents the heating wire from sticking to the clamping plate at the other end after repeated use. The specific process is shown in Figure 5 below.