The Blackjack Dealer
Students: Thomas Eigner, Renjini Narendranath, Tobias Schild
This robot is a Blackjack dealer that plays against the user. It deals cards for itself and for the user according to the Blackjack rules, and counts the points for each player. It recognises when somebody has won, and adds or deducts money from the human player's assets.
The robot deals cards from a stack, which is partially hidden by the palm tree in the picture above, and shown in more detail below.
The small rubber wheels resting on the top card draw the card out a little. It is then captured and drawn out fully by a large rotating rubber wheel, and then moved towards the right-hand side of the earlier picture by a pair of conveyor belts. When it exits the far end of the conveyor belt, it falls down a ramp, face down. The lower end of the ramp has a mechanism for uncovering the card (some cards in a Blackjack game remain face-down until the end of the game).
As the card travels down the conveyor belt and disappears under the skull-and-crossbones cover, it is filmed by a Lego webcam fixed below the conveyor belt. An image recognition program on the PC analyses the pictures and determines which card it was. To simplify the image recognition problem, the students had their own cards printed, which have a unique barcode in the middle, in addition to the ordinary markings for the playing cards in the corners. The image recognition works surprisingly well; the main problem was to provide reliable lighting. After experiments with a 60W light bulb, which was so hot it almost melted the Lego bricks, they ended up with two arrays of white LEDs.
The dialogue revolves around the Blackjack game. The dealer can explain the rules, keeps track of the money and the bets, offers the player to double their bet, etc.
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