Smart TrashBin, Is a robot trash but with sensors! If you already know about robot trashes, This is the basic one. This trashbin use sensors to work, you can just wave your hand in the sensors to open the trashbin. Soo, your hands will stay clean with out touching the trashbin. The  trashbin will close back after you put your trash in there. The sensors uses ultrasonic to know is your hand in there or not, if your hand is waving, the ultrasonic will detected your movement and then it will be open for you!