SAND SAMPLING APPARATUS
Eglin Air Force Base
Gina Teofilak
Richard Klimas
Dan Mortensen
Ruben De Sousa
Overview

Introduction

Current Design

Maintenance and Safety

Design Specifications

Motion Control

Motion Control Components

Obstacles

Cost Analysis

Future Plans
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INTRODUCTION
Introduction
Projectile
Target shot line
Fractured sand
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EGLIN VISIT 10/31/2008
Experimental Changes
Newly added forklift straddles
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CURRENT DESIGN
Current Design
 Uses 2 linear motion actuators for
Y and Z motion
 ¾ inch ACME threaded rod
 Designed to be a lead
screw
 Each will have an aluminum
extrusion frame
 Y and Z are different
sizes
 ¼ inch aluminum rod
stabilizers for support
y
X
z
 motion to be attained from 2
DC motors
 Z- actuator is mounted directly to
the Y- actuator
 Legs of Y- actuator mount to
wheels to produce X motion
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CURRENT DESIGN
Motion in the X-direction
 Chain and sprocket motion
 Wheels fit inside aluminum extrusion
grooves
 DC motor attached to sprocket
 Chain is clamped to actuator
Clamp has teeth of same pitch as the chain
 Chain mount is adjustable for chain
tension
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Future Considerations for X Axis
 Instead of wheels, an eight foot long steel rod is considered with linear
bearings
Steel rod will make it safer for installation than wheel base
Prevents tipping when installing onto experiment
Wheels might tip
Steel rod is cheaper
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Maintenance and Safety
Material are corrosive resistant
Threaded rod is hardened stainless steel
Will not corrode based on interaction with other materials used
Experiment is only ran one time a month
When not used it will be stored in indoor atmosphere
To keep sand out of moving parts:
Bearings with brush guards will used
Plastic accordion style rod boots will cover the lead screws
Plastic guards will be mounted to keep sand out of x- actuator tracks
Lubrication is not required
Bearings are shielded
ACME lead screw does not require lubrication
Safety:
Chain guard
Safety stickers
By all moving parts and electrical components
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Design Specifications
 Size:
Length
96”
Width
27”
Height
24”
 Weight:
Mechanism
70 lbs.
Vacuum
20 lbs.
Electronics5 lbs.
 Vacuum
Power:
6.5 Hp peak
Volume:
20 gallons
(supplied by Eglin)
 Mechanism Speed:
2 in/sec
Motion Control
 Motion control
 3 DC motors/ controllers
 microprocessor
 encoders/ switches
y
 Y axis motion
 threaded rod
aluminum rods for support
X
z
 Z axis motion
threaded rod
vacuum tube rigidly attached
 Control Sequence
 z axis ½”-1”
 y axis 24”
 x axis 4”
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Motion Control Schematic
X Direction Movement
Motor Controller
Encoder
Motor
Z Direction Movement
Wall Socket
Power Supply
Motor Controller
Microprocessor
Encoder
Motor
Switches
Motor
Y Direction Movement
Motor Controller
Control System Schematic
DC Power supply
Microprocessor stores code
Motor Controllers
Distances components
Motors
Geared motors
Required Torque
Required Torque Needed (oz*in)
X movement
20
Y movement
40
Z movement
20
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Motion Control Components
Why use different distance components?
 Encoders
Convert rotations of shaft to code Encoder
Precise measurement of distance
Can be used to input exact position
 Switches
Simple short circuit switches
Easier to program
Cheaper
Encoders
Switches
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Motion Control Obstacles
 Make Screens
 They are a problem
 Break and Deform
 Slightly unequally spaced
 Removed for simplicity
 Suggested from the sponsor
 Projectile Entry Tube
 Adds safety to the experiment
 Cannot be removed
 Mechanism is designed
to avoid
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Cost Analysis
Option
Total (USD)
Machine Shop
Wheels and corrosion
res.chain
1387.53
Wheels and noncorrosion res.chain
1347.33
Rods and corrosion
res.chain
1281.94
Rods and non-corrosion
res.chain
1241.74
Current design is more
expensive than using the rod
Material Cost
Shipping
Testing Facilities
Possible testing table
Cost Comparison for X-axis Options
Cost(USD)
550.00
500.00
450.00
400.00
Rod Option
350.00
300.00
250.00
200.00
150.00
100.00
50.00
0.00
Rod Option
Raw Materials
Donations
Wheels Option
Wheels Option
Parts
Purchased
Control System
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Future Plans
Purchase Parts
Machine and Assemble
December 2 – January 6
Write the program
Test
Write Procedures
Make modifications
Conduct the Experiment
Meet the Class Deliverables
January 6 – April 24
REFERENCES
1.
Cooper, William “Bill”, MSgt Wes Schuler, AFRL/RW
Munitions Directorate
Air Force Research Laboratory
2.
Mortensen, Charles, Owner, Dynatech Associates
3.
Dr. Chiang Shih, FAMU-FSU College of Engineering, Mechanical
4.
Dr. Daudi Waryoba, FAMU-FSU College of Engineering, Mechanical
COST REFERENCES
Carbon Stick tape
http://www.2spi.com/catalog/spec_prep/cond_adhes-discs.shtml
Aluminum Extrusion
Dynatech Associates
McMASTER-CARR
http://www.mcmaster.com/
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Questions?