Transcript manufacture its solar panel

ODU CubeSat
Cornelius Aaron
Heather Culley
Jonathan DeGroff
MAE 435 Midterm Presentation – June 21, 2016
Malcom-Scott Edwards
Josh Frechem
Owen Parkinson
Project Manager: Tevon Taylor
Purpose
• The purpose of this project is to perform scientific research, for a 1U
CubeSat incorporating an aerobrake, to predict orbital decay, and
build prototype elements that can demonstrate communication and
data transmission capabilities.
What is a CubeSat?
• Described by Cal Poly CubeSat Design Specifications
• 10 cm cube up to 1.33 kg mass
• Relatively low cost and development time
• Makes space more accessible to universities and private interests
Typical “1U” CubeSat
Image source: http://www.nasa.gov/sites/default/files/thumbnails/image/m15-146_lunar_orbiter_cubesat.jpg
Chassis style/size comparison
Image source: http://www.americaspace.com/wp-content/uploads/2014/12/Units_of_Cubesat.jpg
Virginia CubeSat Constellation
• Proposed by Virginia Space Grant Consortium (VSGC).
• Project includes undergraduate teams from ODU, Virginia Tech, the
University of Virginia, and Hampton University.
• Constellation will consist of three CubeSats with common objectives.
• Selected for NASA funding as of April 2016.
Science Investigation
• Measure orbital decay of constellation to develop database of
atmospheric properties.
• Region of interest is “thermosphere” (90 to 600 km altitude).
• Atmospheric density varies appreciably both with solar time of day
and as a result of solar activity.
• Understanding the relationship is necessary to predict orbital
lifetimes.
• Accelerometer data collected by constellation will help model
atmospheric activity with respect to both time and location.
Science Investigation (cont.)
• UVA and VT CubeSats will be similar to each other.
• ODU CubeSat will feature a deployable drag brake and will achieve a
different ballistic coefficient.
Science Investigation (cont.)
• Data will be transmitted directly to ground-based receiving station.
• Data may also be uploaded to the Globalstar telecommunications
constellation. This approach offers improved coverage compared to a
ground link.
Technology Investigation
• Develop a system to determine and communicate satellite position
across constellation.
• Will enable constellations to make multi-point observations of
atmospheric phenomena.
• Can be used to develop collision avoidance systems.
Chassis
Main structure of satellite (a.k.a. frame or bus)
Chassis
Size is constrained by P-POD launcher
Chassis
The ODU team has chosen to design and additively manufacture our
CubeSat chassis for several reasons:
• Lower cost
• Lower weight
• Demonstration of effort/innovation
• Proven by previous NASA CubeSat missions
Chassis
Windform XT
• Polyamide reinforced with carbon
• Manufactured through selective
laser sintering
• Can be machined after fabrication
Chassis
Chassis
NASA 3U Windform CubeSat
Drag Brake
• Design concept from the NASA Echo Satellite Project
• Sublimating benzoic acid as gas generator
• Mylar inflatable to prevent from atomic oxygen
degradation.
• Cross sectional of area 1 m^2
Drag Brake (cont.)
Drag Brake – Vacuum Chamber Testing
• Vacuum Chamber at NASA
Power System
• Clyde Space 3G 1U EPS
• Clyde Space solar panels
• Clyde Space integrated battery
Clyde Space 3G 1U EPS
• The Clyde Space third generation (3G ) electrical power system (EPS)
manages electrical power generation, storage and management and
commonly makes up one-third of total spacecraft mass.
Clyde Space solar panels
• The Clyde Space solar panels utilize the
photoelectric effect to generate electrical
current.
• Solar cells, are made out of thin wafers of
semiconductors that produce electric
current when exposed to light. Their
primary function is to charge the battery
and power the electrical loads through the
EPS.
Clyde Space integrated battery
• The Clyde Space integrated battery is used for energy storage and is
equipped with an internal heater. It Is a lithium-based battery which is
commonly used in portable electronic devices because of their ability
to recharge, their low weight, and their high energy capacity.
• Commonly used in CubeSat missions; Clyde Space integrated batteries
are generally connected to a primary energy provider such as a solar
array, are able to provide power on demand, and recharge on their
own.
CubeSats Constellations Currently in Orbit (3D)
CubeSats Constellations Currently in Orbit (2D)
Orbital Drag Simulations
Direct Simulation Monte Carlo (DSMC)
• Thermospheric variations cause premature deorbit
• Highly rarefied above 150km
• Free molecular, nearly collisionless flow (mean free path ~ 20-40km)
• Navier-Stokes Equations do not provide good solutions
• Monte Carlo Simulations are used to stochastically solve the Boltzmann equation
Orbital Drag Simulations - Issues
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Mean Free Path calculations are not developed
Exponential signs are incorrect for some values
Large simulation times for fully developed solutions
Little to compare to for LEO using DSMC
Future Work
• FEA Analysis
• Build Prototype
• Testing at NASA