The document describes the design of an ROV called Jenny to collect data beneath the Ross Ice Shelf in Antarctica. Jenny is a scale model that meets all requirements, including dimensions of less than 58cm x 40cm x 30cm and a mass of less than 15kg. It has a PVC frame, thrusters, buoyancy components, and a camera. Testing showed it has an average speed of 0.595m/s and is neutrally buoyant and stable. Calculations are provided for a full-scale version with dimensions of 1.23m x 0.78m x 0.73m and a top speed of 0.483m/s. Recommendations include additions like a camera housing

1. Jenny
December 1, 2014
In Response to NASA BAA # NNH14ZDA001N
Development of ROV for Ross Ice Shelf Expedition
Sanjana Belani
Caleb Irvin
Ryden Lewis
Emily Thayer
Ryan Wilkie
neptune, inc©

2. Objectives
● Design a Remotely Operated
Vehicle to collect data beneath
the Ross Ice Shelf in Antarctica
● Build a scale model of this ROV
● Provide calculations for a full
scale model of the ROV
● Turn Valve 180° http://www.destination360.com/antarctica/ross-ice-shelf

3. Requirements
The ROV must:
● not exceed a total system mass of 15.0 kg
● not exceed the dimensions : 58cm x 40cm x 30cm
● be able to move in 6 directions of motion
● Incorporate required components and meet design
requirements

4. Design - Jenny

5. Jenny
● Meets size requirements
● Easily maneuverable in any direction
● Average speed of .595 m/s
● Neutrally buoyant
● Capable of being scaled up to full scale

6. Description
● Dimensions: 49 cm x 31 cm x 29 cm
● PVC frame
● Five buoys and two Gatorade bottles for
buoyancy
● Zip ties secure components
● Camera on front, right side

7. Design
31 cm
29cm
49cm

8. Design
(Rear view)
Payload

9. Design
(Top view)
Buoys

10. Design
(Front view)
Bottles
Camera

11. Design
(Rear view)
Thrusters

12. Thruster Placement
● Located in rear corners
● Allows pitch to be easily
changed
● Tight turn radius
● Each controlled
individually by switches
or buttons

13. Circuit Diagram

14. Advantages
● Design allows for easy addition/removal of
components
● Four rear facing thrusters maximize speed
● Inner frame securely protects payload
● Wide surface area to turn the valve

15. Mass Budget
Component Mass (grams)
Payload <10,000.0
Frame 1464.5
Thrusters 944.7
Buoyancy 289.6
Total <13,291.5

16. Calculations
Our ROV is neutrally buoyant so
the force of buoyancy is equal to
the weight of the ROV.
∑F = FB
- FG
0 = FB
- FG
FB
= FG
FB
= 130.38 N
FG
= m×g
FG
= (13291.5g/1000g)(9.81m/s2
)
FG
= 130.38 N

17. Calculations
Drag
D = T
= 25.22 N
Thrust
Forward = 25.22 N
Backwards = 8.19 N

18. Calculations
Top Speed
Forward Vtop speed
=
√(T/(.5AROV
CD
⍴)
= 0.663 m/s
Reverse Vtop speed
=
0.377 m/s
Max Power
Forward Prequired
=VT/ηoverall
= 66.88 W
Reverse Prequired
= 12.35 W

19. Calculations
Center of Gravity
XCG
= 19.1225
YCG
= 16.304
ZCG
= 1.78

20. Testing
● Temperature ≃ 20˚C
● Density: 998 kg/m3
● Achieved average velocity
of 0.595 m/s
● Neutrally Buoyant
● Stable

21. Full Scale Environment
Fluid: Sea water
Density:1028 kg/m3
Water temperature: -2.16˚C
Additional considerations: Sea currents,
Increased pressure and buoyancy, Limited
lighting

22. Full Scale Materials
● Frame: High-Strength Steel
● Propellers: Stainless Steel
● Buoyancy: Syntactic Foam
● Power Source: Lithium-ion battery

23. Full Scale Calculations
Full Scale Dimensions:
λ = 2.5
Ls
= 1.23 m
Ws
= 0.78 m
Hs
= 0.73 m

24. Full Scale Calculations
Full Scale Top Speed:
Vs
= Vm
× λV
= 0.483 m/s
Full Scale Thrust:
TS
= TM
x λT
= 86.12 N
Power:
Ps
= Pm
x λpower
= 166.3 W

25. Recommendations
● Housing for the camera
● More secure protection for thrusters
● More sophisticated controls

26. Conclusion
● Model meets all requirement
● Has a calculated speed of 0.663 m/s and a
recorded speed of 0.595 m/s
● Highly maneuverable
● Compact design

27. Questions?
neptune, inc©
Contact:
neptuneinc@umich.edu
image from: http://www.percyjacksonmovies.com/wp-content/gallery/logos/black.png

28. Center of Gravity
XCG
=((236.175*49)*4+10000*16.3)/(944.7+10000)
XCG
= 19.1225
YCG
=(212.5*7.75)+2(236.175*15.5)/(944.7+212.5+10000)
YCG
= 0.804
(31/2) + YCG
= 16.304
ZCG
= (212.5*29)+(236.175*29*2)/(212.5+944.7+10000)
ZCG
= 1.78