Does anyone have any ideas on a system of sensors which could be able to determine if an object is plastic, glass, aluminum, or tin-coated steel? I have been reading that capacitive sensors could work for and some of the other materials but they seem difficult to use and are probably very pricey… Any ideas would be greatly appreciated!!
You will need to be more specific as to the bounds of the types of objects that are to be analyized, then determine the unique propertys of the materials to be detected. A simple start may be something like plastic and glass are generally non electrically conductive, and aluminum and tin-coated steel are. Lots of ways to do things, but few will be cheap/easy. Perhaps you can more fully describe your project.