reliability assessment test

i have a school project to perform a reliability assessment test on a simple webcam that makes use of a plastic len. Am currently having a problem in designing the circuit diagram of the webcam in question. i am hoping if anyone can help me the circuit diagram or a simple tip on how best to design it and if anyone can tell me the output voltage from a USB port..,. i was thinking 5volts but not sure

You're not going to find much for home build web cams, store bought ones are too cheap to warrant it. If this is just for a reliability study, buy the cheapest one you can find at a local electronics store.