Autonomous Metal Detector Vehicle
(AMDV)
Jared Speer
Lamar Williams Jr.
Nathan Stephan
University of Central
Oklahoma
Department of
Engineering and Physics
Fall 2011
Design Outline
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Brainstorm
Research
Feasibility assessment
Conceptualization
Establishing the design requirements
Preliminary design
Detailed design
Production planning and tool design
Production
Brainstorm
• As an team deciding the actual project was an
project of itself
• Other ideas included:
– War Robot
– Remote controlled car
– Underwater boat (Submarine)
– LCD display
– Autonomous Metal Detector
Brainstorm
• As a team we decided that the AMDV sounded
the most interesting and rewarding project,
but it also sounded the most intimidating
project
• To verify the project was feasible, we had to
conduct research
Research
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We performed research on an myraid of different aspects of the AMDV
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Aspects of the AMDV included
– Hall Effect sensor
– Parallax PING Ultrasonic Sensor
– Vehicle Body
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Chassis
Body
Suspension
– Microcontroller
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Basic Stamp 2sx
– Sensor
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Parallax Ultrasonic Ping Sensor
Metal Detector
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Design of the Sensor
Understanding of Sensor
– Programming
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Synching all of the different aspects of the AMDV to work coherently
Feasibility assessment
• After research, we deduced that this will be a
challenging but achievable project
• Since the AMDV idea was seemed so
interesting, we decided that pursuing this
project would be the best route to take.
Conceptualization
(Preliminary Design)
Conceptualization
(Preliminary Design)
Conceptualization
(Preliminary Design)
Conceptualization
(Preliminary Design)
Schematic of the *final* preliminary design
If we proceed in
this design, it
would not be
autonomous
Conceptualization
• That design was our final design that was in
line with our feasibility requirement.
• We needed to make sure that it met the
design requirements of the professor outlined
in his project requirement list.
Establishing the design requirements
• Dr. Baha and Mr. Richard gave us specific
requirements for us to abide by
• We covered all of the requirements given in
the Term Project Guidelines as shown in a list
in the following slide
Establishing the design requirements
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Output Display
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Audio Output Device
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Parallax PING Ultrasonic sensor
Metal detecting sensor
Actuators, Mechanisms, and Hardware
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On/ Off Switch
Timer to shutdown once metal is detected, automatically switches off
Automatic Sensor Input
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Speaker with 5ohm 4watt specs
Manual Data Input
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Parallax Serial LCD
DC motor
Stepper motor
Suspension System
RC servo motor
Logic, Processing, and Control
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Basic Stamp 2SX
Programmed Logic
Preliminary design
If we proceed
in this design,
it would not be
autonomous
Preliminary design
• Due to time constraints, we realized that
building a chassis, suspension system for
various terrain, and space for the circuits we
had to outsource the body
• We reversed engineered a RC car from New
Bright.
Preliminary design
By using this car, we
already had the
suspension, chassis and
space for all of our
circuits.
Preliminary Design
(Metal Detector)
• The original design that we used was going to
be the use of the hall effect sensors
• Even though we thought that it would be an
feasible venture, it would not be feasible with
the time constraint
Preliminary Design
(Metal Detector)
• The design that we
decided to use was the
much simpler BFO (beat
frequency operation)
• This design had to be
modified to fit our
specific parts.
http://thomasscarborough.blogspot.com/2011/10/bfo-metal-detector.html
Preliminary Design
(Testing and Debugging)
Preliminary Design
(Testing and Debugging)
Preliminary Design
(Testing and Debugging)
Preliminary Design
(Testing and Debugging)
• Our team actually
burned the motor
driver L293D due to
insufficient knowledge
of how much voltage
was needed to go in.
Preliminary Design
(Testing and Debugging)
• So we built an voltage
regulator. This was
the schematic of the
voltage regulator. It
regulates the voltage
that goes into the
motor driver (L293D).
http://freedatasheets.com/datasheetblog/tag/voltage-regulator/
Preliminary Design
(Testing and Debugging)
• Our team was obtaining
inconsistent readings
from our metal
detector.
• We realized that our
speaker was very close
to the circuitry and
metal detector.
Preliminary Design
(Testing and Debugging)
• Since the magnet within
the speaker produces
an magnetic field, it was
causing interference in
the reading we
obtained.
• We rectified this
problem by moving the
speaker away from the
circuitry.
Preliminary Design
(Components)
• We used the Parallax
Servo Motor to steer
the AMDV either left or
right
• The Parallax sensor
worked great in this
project
Preliminary Design
(Components)
• We used the Parallax
Ultrasonic Distance sensor
for the AMDV to avoid
collisions
• It used short ultrasonic
burst to and provides an
output pulse that
corresponds to the time
required for the burst echo
to return to the sensor
• By measuring the echo
pulse width, the distance to
target can easily be
calculated
Preliminary Design
(Components)
• This is the DC motor
that provides the rear
wheel drive
acceleration to the
motor
• We switched motors
due to the first motor
we used was
malfunctioning
Preliminary Design
(Components)
• We went through the
trouble of trying to
figure out exactly the
best coil possible.
• 24 gauge copper wire
and wrapped it 70 times
with an inner diameter
with an inductance 1.25
mH.
Preliminary Design
(Components)
• The LCD is integrated
into the AMDV to
communicate to the
user what it sees.
• It tells you the intensity
of the magnetic field
and to reset it to find
metal.
Final Design
(Pictures)
Final Design
(Schematic)
Final Design
(Flowchart)
Final Design
(Pictures)
Estimated Cost
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Output Display
– Parallax Serial LCD = $ 40
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Audio Output Device
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Speaker with 5ohm 4watt specs = $25
Manual Data Input
– On/ Off Switch = $2
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Automatic Sensor Input
– Parallax PING Ultrasonic sensor = $20
– Metal detecting sensor = $20
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Actuators, Mechanisms, and Hardware
– DC motor = $20
– Suspension System = Donation
– RC servo motor = $40
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Logic, Processing, and Control
– Basic Stamp 2SX = $60
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Total Cost = $ 227.00