First, there is a SIN function. It's not exactly normal, but it is there. Do a search and you'll find a few threads explaining it's idiosyncrocies.
Second, you're going to have to provide a little more info than that. Are you doing this with the optical sensors? If so, how many and in what configuration? What specifically are you trying to do? Are you just trying to find the box? Your range to the box? The angle from your current position to the box? All these things are valid things to do, but they are fairly different in terms of how you go about doing it.
--Rob
P.S. try to make your posts a little easier to read. There's already one thread here that's dead because nobody could understand the question. Remember: periods and capitalization are your friend!
