Ingenious unpowered sensor detects motion by generating ultrasound

Researchers at the Georgia Institute of Technology have created a passive motion/contact sensor that detects motion using only sound. Without electricity, electronics, or batteries. The sensors are small, uniquely shaped metal tags that each emit very specific ultrasonic sounds upon contact. They are smaller than a penny and cost only a few cents each.Continue ReadingCategory: Good Thinking, TechnologyTags: Georgia Tech, Georgia Institute of Technology, Motion sensor, Ultrasound