For Richard Hopkins and Jen Harmel's complete instructions on how to build your own penny slot machine, microcontroller code, and a video of the slot machine in action, click here. To view the parts list, click here.
Gamblers who play engineering students Richard and Jen's handy desktop slot machine simply insert a coin and press a button or pull a handle. Three stepper motor microcontrollers generate a random number between 0 and 7, using this number to spin the three reels to new positions. For a cool visual effect, the reels are spun through multiple rotations. If the reels arrive at a winning combination, "winner" is displayed on an LCD, chimes ring, and a central microcontroller sends pulses to a relay that runs a set of solenoids that push out the winning coins. Viva Las Vegas!
Desktop Slot Machine Parts List
Allied Part #
Parallel 16×2 LCD Display
Bipolar stepper motor driver
1 kV resistor
10 kV resistor
4.7 kV resistor
22 pF capacitor
0.1 µF capacitor
22 kV ceramic photocell
5V dc relay
4 MHz crystal oscillator
NPN power transistor
Additional parts required: 5 PIC 16F84A microcontrollers; 1 bright white LED; 3 bipolar stepper motors; 3 H-bridge with flyback diodes; 1 computer power supply; 1 slot machine N.O. spin button; 1 digital sound module; 1 amplified computer speakers; 1 car emergency brake handle; 1 doorbell
At the Design News webinar on June 27, learn all about aluminum extrusion: designing the right shape so it costs the least, is simplest to manufacture, and best fits the application's structural requirements.
For industrial control applications, or even a simple assembly line, that machine can go almost 24/7 without a break. But what happens when the task is a little more complex? That’s where the “smart” machine would come in. The smart machine is one that has some simple (or complex in some cases) processing capability to be able to adapt to changing conditions. Such machines are suited for a host of applications, including automotive, aerospace, defense, medical, computers and electronics, telecommunications, consumer goods, and so on. This radio show will show what’s possible with smart machines, and what tradeoffs need to be made to implement such a solution.