RTM (Robotic Teller Machine) By Jonathan Daudelin Construction Time : February – June 2006 Parts used : 2 RCX’s, 4 Motors, 4 Sensors, Hundreds of Legos Built for CC:10 ATM Contest

RCX’s: Microcomputers that make up the brain and power of RTM One handles card reading 2 are used One handles keypad and money dispensing Communicate with each other via IR

Reading the Card: When card is inserted, RTM moves it over a light sensor, which scans the color code If correct, RTM matches the card with it’s account and gives access to entering the PIN If wrong, RTM ejects the card and gives no access

Money Dispensers I To separate bills, the bill has to travel through a complex route in order to get out – this friction only lets the top bill come out. A motorized wheel spits out the bills into a container below Wheel is on a beam that can move up or down and still power the wheel. This enables the wheel to continually press on the bills (via rubber band)

Money Dispensers II Three money dispensers that dispense three types of bills : Ones, fives, and tens Stacked vertically above a container, so that bills land in the same spot in the container The bill dispensers were the first thing worked on, as they were the main design challenge

Key Pad Key pad is made up of three buttons : “Switch”, “Select”, and “Enter” “Enter” (only available when withdrawing money) enters the number shown Display shows “0” at the start “Select” selects the current digit When “Switch” is pressed, the display moves up 1 (so if display shows 4, it would change to 5)

Entering PIN PIN is entered via key pad, and can only be entered if a correct card has been inserted PIN consists of five digits, which are selected via the “Switch”, and “Select” keys If PIN is correct, access is given to money withdrawal, otherwise RTM beeps and no access is given Once five digits are selected, RTM determines if the PIN matches the inserted card’s account

Withdrawing Money User selects a desired amount of money using “Switch” and “Select” keys, and then enters that amount with the “Enter” key If it’s greater, RTM clears the screen and you enter a new amount. If less, RTM dispenses the exact amount in tens, fives, and ones (in least number of bills) When an amount is entered, RTM determines whether or not it’s greater than the amount in the user’s account

Depositing Money In back of RTM, a door can be opened, revealing slots Bills can be slid through slots into money dispensing boxes. A “tool” on the door helps push bills in all the way Slots only allow bills to be slid in, but not be taken out

Short History I Money Dispensers were worked on first, as they were the biggest challenge. Card reader and Key pad were made next First card reader worked well, and was used in final version. First key pad didn’t work, so another version was made for the final RTM RTM was made in modules: Money dispensers, Card reader, Key pad, and RCX’s. Then they were put together to form the complete RTM Two prototype dispensers were made before final version.

Short History II Card reader and first key pad – mid March First complete RTM prototype – early April Second complete RTM – mid April First working dispenser module – late February Above models programmed – late March RTM Securified and completed – late April RTM programmed except for firmware bug – early May RTM finalized and bugs fixed – Late May RTM shown and publicized – Early June

Interesting Facts PIN’s and Money Amounts: #1 – $ #2 – $ #3 – $30.00 Lines of code: Program #1 – 232 Program # Cards were designed on computer Programming language used: NQC