期刊名称：Faculty of Computer Science and Information Technology
出版年度：2008
卷号：0
期号：0
语种：English
出版社：Faculty of Computer Science and Information Technology
摘要：ABSTRACT :Generally, people do counting goods or items manually. Now with technology,it is no longer done manually. We can count goods or items with machine calledgoods counter. Goods counter machine is using ultrasonic sensors. It can notonly count number of incoming goods, but also distinguish the goods height.This series of works using the principle of ultrasonic sensors reflection.Ultrasonic sensor works by firing signal continuously from the transmitter witha frequency of 40 KHz each 200μ.
