Creating a Vending Machine with Lego Mindstorm :: Robotics

Creating a Vending Machine with Lego Mindstorm Abstract: Vending machines have come a long way, since their introduction to human society thousands of years ago. Although the basic concept of a vending machine has not changed, modern day technology has significantly enhanced them. Our vending machine is no different. Although our vending machine is not top of the line, it is also not such a bad one either. We started out with building the five main components of a vending machine: the dispenser, trough, selection device, and payment reader entirely out of LEGOs. We decided on a door like dispenser and buttons as a selection device. The payment we decided to accept were barcodes. The only component that was actually giving us trouble was the dispenser. Our first dispenser design was severely flawed. After coming up with a door like mechanism, the dispenser was easily fixed. Although we did prove our hypothesis to be correct, there are still many improvements that we could make such as improving the design to make it easier to maintain. Question: Is it possible to create an operational candy machine with only LEGOs? Purpose: To build a candy machine that is capable of:  · Reading a barcode  · Detecting if it is a fake or not  · Sending a signal to the other RCX to allow to user to: 1) Select the candy 2) While making sure that the machine remains stationary Background: The History of Counterfeiting the US Currency The counterfeiting of money is one of the oldest crimes in history. Therefore I needed to find out the ways I could use a LEGO RCX to recognize a correct bill and reject it if it is fake. The History: During the American Revolution, the British counterfeited U.S. currency in such large amounts that the Continental currency soon became worthless. "Not worth a Continental" became a popular expression that is still heard today. During the Civil War, one-third to one-half of the currency in circulation was counterfeit. At that time, approximately 1,600 state banks designed and printed their own bills. Each bill carried a different design, making it difficult to detect counterfeit bills from the 7,000 varieties of real bills. A national currency was adopted in 1862 to resolve the counterfeiting problem. However, the national currency was soon counterfeited and circulated so extensively that it became necessary to take enforcement measures. Therefore, on July 5, 1865, the United States Secret Service was established to suppress the wide-spread counterfeiting of this nation's currency. Although the counterfeiting of money was substantially suppressed after the establishment of the Secret Service, this crime still represents a potential danger to the Nation's economy.