Material Identification using Electronic Sensors
Steven Robertson
Note: Click on image to access poster
Summary
In a previous project I developed a circuit that I used to sort objects into two categories, metallic and nonmetallic. This was accomplished using an infrared phototransistor circuit to detect the presence of an object, and an inductive proximity sensor to identify which objects are metallic. A process like this could be useful in an industrial automation system such as material handling or sorting of recyclable materials. I found that the proximity sensor could detect ferrous metals from a greater distance than nonferrous metals, and that the phototransistor had different results depending on how translucent the material is. Using this information, I developed a system that can correctly identify a variety of metals and plastics. The metals are identified based on the sensing distance of the proximity
sensor, and the plastics are identified by using a microcontroller to determine the amount of light received by the phototransistor.
