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Is it possible

ok im a beginner at this havent even made one yet. but is it poosible to make a robot that picks up a coin identifies if its a penny nickel dime or quarter and places it in a buckket or conatiner… the robot would also keep trck of the money counted so far and at the end display it somehow. if this is possible to do could you tell me costs for it and possible tell me how it works. im not sure where to buy parts a parts list would be nice to… and how do i program stuff into the chip. thanks

Coin sorting is an interesting first project in robotics. It seems like it would require either some fancy sensors or a slick way to sort coins mechanically by size. Vending machines go by size and/or weight, but there are also inductive sensors that can tell the difference between coins that are very similar in those two respects, like American and Canadain quarters. Mechanical size sorting is probably the simplest way to go, but if you want a real robot to do this (and not just a digital coin sorter or a coin counting jar) you’re going to need to build something with a lot of moving parts, a few sensors, and a microcontroller to coordinate everything and keep and display the tally.

Searching around a little it looks like Lego Mindstorms NXT sets are popular for coin sorter robot projects, like this one, and this one. The first one is, I think, a little nicer, and there’s a more detailed description of how it works here.

Personally I’m not a big fan of using NXT kits in, say, robotics classes/clubs/camps, since they use a Lego version of LabView (yes, National Instruments LabView) to write programs. Basically in LabView, instead of writing lines of code, you drag and drop icons that represent operations, then draw virtual wires in between them to direct the flow of the program. I guess it does fit with the building blocks style of Legos, but you miss out on the experience of writing in a real programming language. On the other hand (much as I hate to admit it) full LabView is used in a lot of, you guessed it, professional research laboratories. If you’re just getting started with robots and have no programming background, this is one way you might want to go. A Mindstorms NXT starter kit will cost you a couple hundred dollars, and you may need to pick up extra sensors that aren’t part of the starter kit.

Keep in mind that this is just one possible way to go. Where did you get the idea to build a coin sorter as your first robot?


Go to your local bookstore. Odds are really good that you will find a book on how to program the NXT using another computer language.