Autonomous Metal Detector Vehicle (AMDV) Jared Speer Lamar Williams Jr. Nathan Stephan University of Central Oklahoma Department of Engineering and Physics

Autonomous Metal Detector Vehicle (AMDV)

Jared SpeerLamar Williams Jr.

Nathan StephanUniversity of Central

OklahomaDepartment of

Engineering and Physics

Fall 2011

Design Outline

• 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• We performed research on an myraid of different aspects of the AMDV

• Aspects of the AMDV included– Hall Effect sensor– Parallax PING Ultrasonic Sensor– Vehicle Body

• Chassis • Body• Suspension

– Microcontroller• Basic Stamp 2sx

– Sensor• Parallax Ultrasonic Ping Sensor• Metal Detector

– Design of the Sensor– Understanding of Sensor

– Programming• 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)




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

• Output Display – Parallax Serial LCD

• Audio Output Device– Speaker with 5ohm 4watt specs

• Manual Data Input – On/ Off Switch– Timer to shutdown once metal is detected, automatically switches off

• Automatic Sensor Input – Parallax PING Ultrasonic sensor– Metal detecting sensor

• Actuators, Mechanisms, and Hardware– DC motor– Stepper motor– Suspension System – RC servo motor

• Logic, Processing, and Control– 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)




• Our team actually burned the motor driver L293D due to insufficient knowledge of how much voltage was needed to go in.


• 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/


• Our team was obtaining inconsistent readings from our metal detector.

• We realized that our speaker was very close to the circuitry and metal detector.


• 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


• 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


• 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


• 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.


• 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• Output Display

– Parallax Serial LCD = $ 40• Audio Output Device

– Speaker with 5ohm 4watt specs = $25• Manual Data Input

– On/ Off Switch = $2 • Automatic Sensor Input

– Parallax PING Ultrasonic sensor = $20– Metal detecting sensor = $20

• Actuators, Mechanisms, and Hardware– DC motor = $20– Suspension System = Donation– RC servo motor = $40

• Logic, Processing, and Control– Basic Stamp 2SX = $60

• • Total Cost = $ 227.00

Documents

Autonomous Metal Detector Vehicle (AMDV) Jared Speer Lamar Williams Jr. Nathan Stephan University of Central Oklahoma Department of Engineering and Physics