Final Design ReviewAutonomous Hovercraft

Mechanical Engineering 8936Term 8 Design Project

April 3, 2012

INTRODUCING

2SPROCKET

AgendaProject ScopeDevelopmentDesign SpecificationsExecutionFinal PrototypeHardwareCode Logic DiagramRisksProject ManagementProject ChallengesFuture Considerations

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Project Scope

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The objective of the design team is to design and build a hovercraft that is:

Autonomous - Able to navigate a proposed path free of operating input.

Path should be free of:DisturbancesObstacles

Development

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Component TestingSkirts Motors/Fans Sensors

Parameter Study

Governing Equations

Design Specifications

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Parameter Specification Final Parameter

Diameter < 20 inches 15.5 inches

Total Weight < 5 kg 1.5 kg

Nominal operational Speed ≈ 5 km/hr 4.5 km/hr

Turning Radius < 2x Diameter < 15.5 inches

Acceleration > 0.14 m/s^2 0.2 m/s^2

Deceleration > 0.14 m/s^2 0.2 m/s^2

Execution

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Prototype TestingSensors Parameters Gains

Controls Integration

Control Board Sensors Logic

Parameter DeterminationYaw Drag Dart

Effect Inertia Thrust

Prototype Construction

Body Skirt Mounts

Final Prototype

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Range Finding IR

Compass

Control Board

Wall Detection IR’s

Control Board Battery

Drive Battery

Thrust Motors

Top View

Power MOSFET

Final Prototype

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Bottom View

Motor

CentrifugalLift Fan

Baffles

Skirt

HardwareRomeo Control BoardArduino BasedIntegrated Motor DriverAllows for Bluetooth, GPS, Servo Motor Future\ Expansion

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Code LogicTravel Down HallwayIdentify CornersPerform Turns in Sequence & Stop

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Code Logic Diagram

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Code Logic Diagram

Risks

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Type Hazard ControlSafety

Sharp Corners Eliminate Sharp CornersExposed Props Cover Props if Dangerous

Electrical and Batteries Contain Electronics Environment

Batteries Dispose of hazardous waste properly

Material Try to eliminate waste and material used

Cost

Over BudgetHave a contingency and

use old parts already purchased

ScheduleOverruns Weekly Update Schedule

Project Schedule

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Project Timeline (weeks)

January February March April

Consecutive Week 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16

Dates

8 Ja

n - 1

5 Ja

n

16 J

an -

22 J

an

23 J

an -

29 J

an

30 J

an -

05 F

eb

06 F

eb -

12 F

eb

13 F

eb -

19 F

eb

20 F

eb -

26 F

eb

27 F

eb -

04 M

ar

05 M

ar -

11 M

ar

12 M

ar -

18 M

ar

19 M

ar -

25 M

ar

26 M

ar -

01 A

pr

02 A

pr -

08 A

pr

09 A

pr -

15 A

pr

16 A

pr -

22 A

pr

23 A

pr -

29 A

pr

1.1 Project Definition1.2 Scope1.3 Research1.4 Simulation1.5 Procurement1.6 Construction1.7 Testing

2.0 Project Definition2.1 Project Scope2.2 Definfing Project Roles2.3 Defining Hovercraft Path2.4 Defining Existing Material Invetory

3.0 Research3.1 Basic hovercraft theory3.2 Skirt Material

3.2.1 Foam3.2.2 Rubber3.2.3 Cloth

3.3 Hardware & Sensors3.3.1 Motors3.3.2 Arduino Board3.3.3 Compass3.3.4 IR Sensors3.3.5 Sonar3.3.6 Gyro

3.4 Fans3.4.1 Lift Fan3.4.2 Thrust Fans

4.0 Simulation4.1 Understanding Governing Equations4.2 Parameter Study

4.2.1 Root Locus Plots4.2.2 Simulink Simulation

4.3 Determination of Parameters4.4 Determining Various PID Gains

5.0 Procurement5.1 Arduino Board5.2 Sonar Sensor5.3 Compass5.4 Gyro Sensor5.5 Motors

6.0 Construction6.1 Body6.2 Skirt6.3 Motor Mounts6.4 Sensor Mounting6.5 Battery Mounting

7.0 Testing7.1 Parameter Testing

7.1.1 Mass7.1.2 Moment of Inertia7.1.3 Yaw Damping7.1.4 Dart Effect7.1.5 Prop Torque7.1.6 Friction

7.2 Thrust Fan Testing7.3 Sensor Testing

7.3.1 Sonar7.3.2 Compass7.3.3 Gyro7.3.4 IR Sensors

7.4 Integration of all sensors7.5 Path Testing

1.0 Mini Design Report #11.1 Mini Design Presentation #1

2.0 Mini Design Report #22.1 Mini Design Presentation #2

3.0 Final Report3.1 Final Presentation

1.0 Mini Design Report #1 30-Jan1.1 Mini Design Presentation #1 30-Jan

2.0 Mini Design Report #2 28-Feb2.1 Mini Design Presentation #2 28-Feb

3.0 Final Report 4-Apr3.1 FinalPresentation 4-Apr

High Level Design

Detailed Design

Submission Preparation

Objectives / Milestones

1.1 Project Definition1.2 Scope1.3 Research1.4 Simulation1.5 Procurement1.6 Construction1.7 Testing

High Level Design

Project Budget

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Starting Budget

Faculty of Engineering $ 250.00

Group Members $ 200.00

Total Budget: $ 450.00

Costs to Date

Sonar Range Finder $ 26.89

Gyroscope $ 41.19

Digital Compass $ 37.11

DF Robot Microcontroller $ 37.11

Propellers $ 6.00

Motors $ 12.00

HST/S&H $ 31.10

Total Project Cost $ 191.40

Remaining Funds $ 258.60

Project ChallengesUncontrolled Environment

Non-uniform Test SurfacePedestrian TrafficObstaclesMagnetic Interference

Battery Inconsistency

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Future ConsiderationsBluetoothSensorsCoverPrototype SizeVideo Surveillance

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ReferencesBeardmore, Roy. Root Locus Methods. Ed.

Roy Beardmore. N.p., July. Web. 17 Jan. 2012. <http://www.roymech.co.uk/Related/Control/root_locus.html>.

Kalpakjian, Serope, and Steven Schmid. Manufacturing Engineering and Technology.

Fifth ed. Upper Saddle River: Pearson Education, 2006. N. pag. Print.

Rethwisch, David G. Materials Science and Engineering An Introduction. Seventh ed. New York: John Wiley & Sons, 2007. Print. 19

Project Website

www.autonomoushovercraft.yolasite.com

Please Visit!

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Thank You!

Special Thanks to:Professor Michael Hinchey

Tom PikeSteve Steele

Craig Mitchell

Please Feel Free To Ask Any Questions

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Back up

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Design Parametersα = Hovercraft Angle Headingβ = Hovercraft Angle of VelocityE = Drive ForceF = Friction ForceT = Yaw TorqueM = Mass I = Yaw InertiaK = Dart Effect J = Yaw DragX = Prop Coefficient Relating Ramp up SpeedY = Prop Coefficient Relating Maximum TorqueZ = Coefficient of Friction

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Governing Equations

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Equations of Motion Drive Equation

Yaw Control

Translation Control

Simulation

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Variable Effect Design Considerations

Mass: MFaster response more damping for smaller

valuesLightweight

Moment of Inertia: I

Faster response for smaller values, damping

effect negligible

Mass located to reduce moment of inertia

Yaw Damping: J

Response speed decreases with increasing

values. Damping only signification for J = 0.

Low yaw damping desirable

Dart Effect: K

Unstable for negative values, slower response

for increasing values, negligible damping

Balance mass as well as possible, front heavy is unstable, back heavy is

stable but reduces response time

Prop Torque: Y

Poor damping at low values, negligible

response speed until a crit ical value where

response speed decreases

Ensure sufficient torque available for fast

response, control system design to compensate for

poorer damping

Friction: Z Faster response, more damping at higher values High friction desirable

Sprocket in Deep Tank

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