EGR 450
Manufacturing Control Systems
Project
Skeeball Machine
Colleen Koperski
Michael Powell
Nicholle Schutter


Description:

A skeeball machine was constructed with a two foot by four foot alley and a digital display run by a PLC.  The game is played by individually throwing five three-inch balls down the alley where they will hit a ramp and fall into one of three point valued holes.  The holes are valued at 10, 20 and 50 points.  When the game is turned on the high score will be shown on the display.  Once the start button is pushed the score and ball counter will turn to zero and the game is ready to be played.  Every time a ball falls through one of the three holes the corresponding point value will be added to the score and the ball counter will advance.  If the current score becomes higher than the high score then a light will go off.  Ten seconds after the fifth ball has been thrown the high score will reappear which hopefully is your score.  The high score is able to be reset by pushing the red button in case the highest score possible is reached or one wishes for it to be reset.

STATE DIAGRAM
Materials
Quantity & Length
Item
1
PLC 5/11
4
Digital LEDs
numerous
 Wires
2
Push Buttons
3
Buttons (Sensors)
 4
LED Lights
1
DC Power Supply
(Cadet Trainer)
3
BCD to 7 Segment Display
1
Bread Board
32
1.8k Resistors
1 @ 4'X4'
3/8" Plywood 
4 @ 8'
 2X2
2 @ 8'
 Furring Strip 
3
3" PVC Connectors
1 @ 5'
4" PVC 
2 @ 2'X4'
1/8" Black Sheet of Plastic
1 @ 4'
2"X4"
5
3" Croquet Balls

WIRING DIAGRAM

INPUTS
OUTPUTS
START BUTTON
BCD OUTPUT A (CHIP 1)
RESET BUTTON
BCD OUTPUT B (CHIP 1)
10 PT SENSOR (BUTTON)
BCD OUTPUT C (CHIP 1)
20 PT SENSOR (BUTTON)
BCD OUTPUT D (CHIP 1)
50 PT SENSOR (BUTTON)
BCD OUTPUT A (CHIP 2)
 
BCD OUTPUT B (CHIP 2)
 
BCD OUTPUT C (CHIP 2)
 
BCD OUTPUT D (CHIP 2)
 
BCD OUTPUT A (CHIP 2)
 
BCD OUTPUT B (CHIP 3)
 
BCD OUTPUT C (CHIP 3)
 
BCD OUTPUT D (CHIP 3)

 

LADDER LOGIC


Different Views of the Skeeball Machine:

Angled Side View
Point Rings
Ball Return
Digital LED Wiring
PLC Wiring
Digital LEDs
Side View
Start Button
Close-up of Digital LEDS

 


Design Considerations:
One thing to consider when building the skeeball machine are the button/sensors that are pushed when the balls fall through the holes. The buttons that were used needed to be fully pressed for the points and ball throw to be counted. This was somewhat of a problem due to the ball fallings through the hole which is slightly too large of a diameter and that the hole had a lip half-way through which caused the ball to rise over the button. This was solved by adding a piece of cardboard to the inside lip which caused the ball to fully press the button.



Cost and Building Suggestions:
The cost of building the machine was roughly $50 excluding labor and the PLC.  The PLC would greatly increase the cost and is not recommended for that reason  in running the machine.  A chip with the downloaded program on it would be suggested.

Special Thanks to: Ron,  Jonathon & Jay.
 
 
 
 


Nikkie, Mike & Colleen