NAU RoboSub Mansour Alajemi 1 , Feras Aldawsari 1 , Curtis Green 2 , - - PowerPoint PPT Presentation

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NAU RoboSub Mansour Alajemi 1 , Feras Aldawsari 1 , Curtis Green 2 , - - PowerPoint PPT Presentation

Nov 08, 2023 455 likes •796 views

NAU RoboSub Mansour Alajemi 1 , Feras Aldawsari 1 , Curtis Green 2 , Dan Heaton 1 , Wenkai Ren 1 , William Ritchie 2 , Bethany Sprinkle 1 , Daniel Tkachenko 1 1 Department of Mechanical Engineering 2 Department of Electrical and Computer Engineering

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SLIDE 1

NAU RoboSub

Mansour Alajemi1, Feras Aldawsari1, Curtis Green2, Dan Heaton1, Wenkai Ren1, William Ritchie2, Bethany Sprinkle1, Daniel Tkachenko1

1Department of Mechanical Engineering 2Department of Electrical and Computer Engineering

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SLIDE 2

Overview

  • Introduction
  • Competition tasks
  • Needs/Goals
  • Constraints/ Features
  • Camera Box
  • Endcaps

2

  • Externals
  • Internals
  • Electrical
  • Software
  • Conclusion
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SLIDE 3

Introduction

  • Robosub 2016 competition
  • Client: Dr. Kosaraju
  • NAU’s first time participating

3 [1] AUVSI foundation

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SLIDE 4

AUVSI Robosub Competition

In the competition the sub will gain points for:

  • Bumping two buoys in order (red then green)
  • Pulling a third yellow “buoy” downward, “scuttling” an attached boat floating on surface
  • Passing through a pvc U (8’ by 4’)
  • Dropping markers into 2 plastic bins

○ One bin has a cover with a PVC handle that needs to be removed

  • Firing torpedoes through 12” and 7” squares
  • Surfacing in a 9’ octagon marked with a pinger 16’ below the surface acoustic pinger

○ Extra points for carrying an object up from the floor then descending and placing near an X

4

2016 competition theme: Pirates

[1] AUVSI foundation, [2] Skull and Crossbones

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SLIDE 5

Robosub Needs/Goal

  • Needs: NAU has no robosub for the AUVSI competition
  • Goal: complete a new robosub ready for competition in July 2016

Includes aspects from :

○ Mechanical ○ Electrical ○ Software

5

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SLIDE 6

Constraints

  • Autonomous
  • Fits in 6’ x 3’ x 3’ volume
  • Has waterproof kill switch
  • Must be at least 1% buoyant
  • 15 minute time limit
  • Weighs less than 125 lb

○ Extra points for weight < 84lb, 48.5lb, 22lb

6

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SLIDE 7

Required Features

  • Water tight enclosure

○ Obstacles are max 16’ deep (~22 psi)

  • External frame

○ Mounts sensors and thrusters

  • Electrical circuit
  • Internal frame for electronics

○ Must account for heat

  • Autonomy software

7

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SLIDE 8

8

Camera box Plane thrusters Orientation thrusters Power tube Control tube Ballast tube

Final design of Trident

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SLIDE 9

Camera Box

  • Front and bottom facing cameras

○ 3D print mount

  • Acrylic windows sealed with epoxy &

silicone

  • Epoxy and clamps to fasten to body
  • Rubber gasket between tube
  • Problems…

○ Tube not perfectly circular

9

PVC box Seals Windows Camera mount Clamps

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SLIDE 10

End Caps

  • Through ports for cables
  • Water tight

○ O-rings x3 per end cap

  • Aluminum end caps

○ Machinability ○ Heat release from system

10 [3] Blue Robotics

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SLIDE 11

Manufacturing End Caps

  • Drilled holes for cables
  • Drilled holes through bolts
  • O-rings/epoxy for water tightness

11

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SLIDE 12

External Design

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  • Metal-frame design

○ Three tubes, bottom for ballast ○ Rigid metal construction ○ Difficult to mount external systems

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SLIDE 13

External Frame

  • Changed due to unexpected instabilities

○ Sheet metal strips / angle brackets ■ Angle brackets provide rigidity ■ Strips provide stability ○ Threaded rod holds construction rigidly together

  • Alternatively: 3D print from ABS plastic

■ Mechanically superior to PLA

  • Stronger
  • Low risk of delamination
  • Superior finishing qualities (sanding, drilling)

■ Faster and cheaper to manufacture

13

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SLIDE 14

L Channel connection for Thruster

  • Increases strength on the U and X shape brackets
  • Prevent torsion problem between tube and brackets
  • Can be moved for relocation

14

Nick named, “Frankenstein”

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SLIDE 15

External design: Completed prototype Trident

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Nick named, “Frankenstein II”

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SLIDE 16

Internals Introduction

16

  • Modular design

○ Mix and match sections

  • Repurposed misprinted sections
  • Heat sinks for:

○ Electric Speed Controllers (ESCs) ○ Batteries

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SLIDE 17

17

Internal Frame Assembly

17

Big batteries board ESC Small batteries RPI DB-25 Cat 5 board usb Big batteries terminal terminal buck DB-25 Typical cross section 4-2 connector

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SLIDE 18

Internal design with the hardware

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SLIDE 19

Electrical Subsystems

  • Hardware

○ Power ○ Control

  • Software

○ Visualization ○ Communication ○ Orientation ○ Motor feedback ○ Sonar

19

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SLIDE 20

Electrical Concept Generation

Hardware & software

  • Talk to grad students and professors
  • Look at competing teams
  • Work with what we know
  • Learn what we should know
  • What components and libraries we need
  • What circuits and algorithms to develop

20

Raspberry Pi

[4] Python, [5] Arduino, [6] Raspberry Pi

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SLIDE 21

Final Circuit Design

21

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SLIDE 22

Final Software Design

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SLIDE 23

Image Detection

23

Threshold applied Green circle detected Threshold applied Orange line detected

[10] OpenCV Documentation, [11] OpenCV install Tutorial

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SLIDE 24

Electrical Prototype Fabrication

Basic motor feedback of visual processing Test system set up

24

Assembling the internals

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SLIDE 25

EE Design Modifications

  • Buck converters added
  • Relay for main power On/Off
  • DB communication cable
  • Queued Socket Programming
  • Simplified Software

25 [7] Amazon

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SLIDE 26

Completed Electrical Hardware Prototype

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SLIDE 27

EE Performance

Software

  • Find and kill ghost threads
  • Computation time testing
  • Find programing bugs

○ Threading issues ○ Lock passing issues

  • Image detection:

○ Lighting ○ Threshold parameters ○ Image size ○ Decipher image data

Hardware:

  • Find and fix bad circuit elements
  • Find and fix unwanted behaviour
  • Eliminate motor controller heat
  • EM Noise in the DB cable

27

Finding Board shorts ESC heat to hull (W/ no foil)

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SLIDE 28

Testing and Results

Video

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SLIDE 29

Development for the future

  • Torpedos
  • Clasping
  • Sonar
  • Practice course construction
  • Mechanical updates
  • More programs

29

Sonar data Clasping system Torpedo System

[8] Sonar ping

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SLIDE 30

Conclusions

  • Designed a submarine for 2016 Robosub competition
  • Educational experience
  • Manufactured systems

○ Camera ○ External ○ Internal ○ Electronics ○ Software

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SLIDE 31

Acknowledgements

  • Mr. Steve Hengl, Orbital ATK
  • EE & CS professors for advice

○ Julie Heynssens ○ Philip Mlsna ○ Dieter Otte ○ James Palmer

  • The 98C shop staff:

○ Perry Wood ○ John Tester ○ Ricardo Inzunza ○ Derrick Lemons

  • Dr. Kosaraju for guidance

31 [9] orbital ATK logo

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SLIDE 32

References

1. “Robosub 2016 Preliminary Mission and Scoring” Dec 12, 2015. http://www.auvsifoundation.org/competitions/competition-central/robosub/robosub-team-central 2. Skull and crossbones http://www.playcrossbones.com/Jolly_Roger_Flag.php#sthash.ALQDy6CK.dpbs 3. Blue Robotics https://www.bluerobotics.com/store/ 4. Python Symbol https://realpython.com/learn/python-first-steps/ 5. Arduino Image https://electrosome.com/arduino/ 6. Raspberry Pi Image https://www.raspberrypi.org/ 7. Amazon online item images http://www.amazon.com/ 8. Sonar data picture http://www.bathyswath.com/iho-standards 9. Orbital ATK logo http://www.aerospacemanufacturinganddesign.com/article/orbital-atk-aerospace-merge-050114/ 10. OpenCV documentation http://docs.opencv.org 11. OpenCV install tutorial http://www.pyimagesearch.com/2015/02/23/install-opencv-and-python-on-your-raspberry-pi-2-and-b/ 32

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SLIDE 33

Questions?

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