Transcript Automated Electromagnetic Crane

Automated
Electromagnetic
Crane
Greg DeKing
Fran Simmonds
Principles of Design
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Functionality
Mechanical Design
Sensor Design
Embedded Design
Cost
Problems
Questions
Functionality
The Automated Electromagnetic
Crane locates, acquires, and
removes steel blocks from a target
area to a designated container in
an uninterrupted sequence.
Specifications
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Runs in fully automated mode.
User may pause operation and
move blocks.
All blocks are relocated after every
“grab” operation.
Closest-to-bucket order of pickup.
Limitations
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All blocks must be fully inside
target area.
If a block is dropped the “drop”
operation will still proceed.
Blocks must be of a conductive
material with a strong magnetic
field.
Designer imposed
constraints
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High success rate.
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Sensors.
Low cost.
Stationary.
Battery power.
Components
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HC12
Duramag ER1-071 Electromagnet
3 12V Stepper Motors
8 74151 8-1 Mux
OPB 745 Optoisolator
Duramag ER1-071
Electromagnet
Part Number
Diameter
Length
Thread
12
VD
C
24
VDC
110
VDC
A
B
T
ER1
-071
ER2071
-
3/4
1-1/4
10-32
Tap
Dept
h
Lead
Location
Lead
Length
Watt
s
G
3/8
3/16
*Holding
Value
Net
Weight
Lbs.
24"
1.5
6
1.7 oz.
Motors
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12V Airpax stepper motor
2 12V NMB stepper motors
Stepper interface boards
Optoisolator
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Inductive spike caused from
switching magnet off.
25.5 Volt magnitude.
Separate 12V source.
Magnet on/off controlled by
optoisolator circuit.
Mechanical Design
Mastercam – side view
Mechanical Design
Tower Support
Mastercam -- top view
Sensor Placement
Sensor Design
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Conductive rings separated by
non-conductive material
Inside rings of row in series
Outside rings of column in series
Sensor Function
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Input signal applied to inner ring
Block completes circuit
Corresponding mux control
HC12 reads voltage “hit”
Interfacing
MULTIPLEXER SYSTEM
Sensor Map
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37 bytes.
Each byte 1 Column.
Each bit represents row number.
Sensor sweep will fill sensor map
one row at a time.
 When all 37 columns for each row
complete next row will begin.
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Embedded Design
begin
Loop
next
read AD
store AD in TEMP
change MUX controls
ITERATION += 1
bit test bit 0
branch {bit not set} to next
set bit MAP_POINTER + BIT_POINTER
MAP_POINTER += 1
Shift TEMP
Test ITERATION
branch {less than 8 } to loop
ITERATION = 0
Test MAP_POINTER
Branch { less than 37 } to begin
BIT_POINTER += 1
Test BIT_POINTER
Branch {less than 8} to begin
BIT_POINTER = 0
Foreseeable Problems
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Multiplexing of I/O.
Blocks contacting multiple sensors.
Two Blocks on same sensor.
Cost
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Electromagnet $40.00
Motors
$15.00
Circuit Boards $30.00
Muxs
$15.00
Aluminum
$60.00
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Total
$180.00
Questions
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Any Questions ?