I need to sense vibration of an object, but I can't use accelerometers or piezo sensor because those requires touching the object, which is impractical in my application.
I hope to use an optic based approach, or any other method that can sense the degree of vibration without contact. I need to be able to feed the data into an Arduino or a PC.
I don't want to have to buy a big/expensive industrial type device. Size and price matters. However, I can place the sensor very close (millimeters) to the object. Any ideas?
thanks