Space Science and Engineering Lab

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The Montana Nanosatellite for Science,
Engineering, and Technology for the AFRL/NASA
University Nanosat Program, (Maia)
System Concept Review
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Maia Mission Statement

• The Montana State University Maia University
  Nanosatellite Project will characterize
  magnetospheric energetic charged particle
  variations near earth using new state-of-the-art
  solid state particle detectors. It will
  demonstrate operation of a novel on-orbit
  deployment system and the use of newly-developed
  miniature hybrid magnetoresistive magnetometers
  for attitude control.

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Maia Objectives

• ENGINEERING
• Testbed for technologies
• Science support platform
• Deploy a solar power wing
• Active 3-axis attitude control
• SCIENCE
• Measure variations in the charged particle flux
  near Earth
• Solid state technology
• Effects of solar storms on ionospheric energy
  input
• TECHNOLOGIES
• Elastic memory composite hinge
• Magnetoresistive magnetometer sensor-based ACS
  control system
• Consumer parts and subsystems

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Maia Success Criteria
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Maia Payload

• Multi-element charged particle telescope
• Low energy solid state detector
• Characterize the particle flux during active
  periods
• ISS and shuttle low-earth orbits are susceptible
  to radiation hazards
• How does the particle flux change with
  geomagnetic storms?
• What is the quite time steady state count rate?
• Demonstrate new low energy (1keV) solid state
  detectors

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Maia StructurePhilosophy

• A load-bearing aluminium endo-skeleton
• Isogrid base plate (SIP)
• Stacked electrical cage design
• Non-structural shell
• Approximately 18 across and scalable in height
• Targeted at 10 kg
• Deployable Solar panel

load-bearing
non-structural shell
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Maia DeployableSolar Panel

• Roughly the same size as a shell face
• Solar cells on both sides of deployable and on
  underlying surface
• Elastic memory composite hinge system (TEMBO)
• Rigid launch constraint
• Cup and cones
• Pre-load panel
• Single latch
• Hinge is non-load bearing in stowed position
• Not over constrained

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Maia PowerPhilosophy

• Plan to string solar panels in 16V strings to
  maximize conversion efficiency to both 5V and 12
  V
• Dual junction GaAs cells
• Planning on Li batteries
• Downside is increased safety scrutiny
• Battery box?
• Semi-regulated bus
• Control the charging of the batteries not the
  discharging
• Maximize the use of not only commercial-off-the-sh
  elf parts but also consumer-off-the-shelf parts
• The use of these parts leads to lower cost and
  often easier use
• Downsides are lack of space heritage and not
  radiation hardened

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Maia CommunicationsPhilosophy

• Would like to operate in C band (3.6 7 GHz)
• Commercially produced radio
• Utilize patch antenna
• Design around no attitude control (worst case)
• Requires multiple antennas to achieve full angle
  coverage
• Try and achieve as high a data rate as possible
• Probably 9600 baud
• 3W RF-output
• Standard sliding window packet protocol
• Link error correction
• Hardware Reed-Solomon encoding looks to be a good
  candidate

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Maia CDH

• Virtually autonomous operation
• Main processor with in-house real-time operating
  system
• ADCS microcontroller/power microcontroller
• Again based around COTS parts
• Motorola HC12 and HC08 families
• Plan to implement an on orbit error checking file
  system in the onboard mass data storage to
  protect data integrity
• Base communications around mission goals and
  noisy downlink
• Error correcting codes included in downlink etc
• No on-orbit reprogramming
• Finite command uplink library

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Maia Operations

• We plan to operate a ground station from Bozeman,
  Montana
• 45 40 32 N, 111 03 59 W elev 1356.7m
• Certainly open to secondary ground stations at
  other universities, AFRL, and/or NASA/GSFC
• Commercially available amateur radio equipment
• PC based acquisition and control
• Combination of in-house and commercial software
• Autonomous mission requires only data downlink
  and setting modes through uplink
• Approximately two 10 minute downlinks per day can
  be expected
• Student run (especially at 2am)

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Risk Assessment/Mitigation

• Safety
• We are planning an unpowered bus exception as
  defined in NSTS 1700.7B
• Eases monitoring and safing of inhibits
• No reason that we cant launch dead
• All aluminium structural components
• Composite solar panel hinge is non-structural in
  stowed position
• No pyrotechnics
• No pressure vessels
• No propulsion

• Management
• Well defined requirements
• Scope that can be scaled back due to problems
  with
• Safety
• Engineering
• Personnel
• Schedule
• All teams at least buddy system
• No one person can leave project and take critical
  information with them
• Promote intra-team communication

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Phase A Concept Development Organization(Febru
ary March 2003)

• In this 7-week phase, undergraduate teams were to
  design the entire satellite (impossible task)
• Present their work in a design review
• Proves to be an easy way for new members to gain
  some familiarity with satellite systems
• Encourages teamwork
• Allows PM to evaluate prospective team members

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Phase B, C, D Concept Development
Organization(April 2003 February 2005)
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Maia Test Plan

• On-site
• Subsystem functionality
• Breadboard level
• Prototype level
• EDU
• Flight
• System functionality
• Multiple subsystems
• Thermal
• Thermal vacuum
• Shuttle certification

• Off-Site
• Shake
• Payload calibration
• Launch system interface
• Acoustics?
• EMI/EMC?
• Shuttle certification

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Education/Public Outreach

• Satellites are not common place in Montana
• Public needs to know why this pursuit is
  important for the state and its people
• Newspapers/television
• Team member talks at regional high, middle, and
  grade schools
• Involvement from and outreach to other regional
  colleges
• Web site
• http//www.ssel.montana.edu
• Part of the Montana Space Grant Consortium, Space
  Public Outreach Team (SPOT) program

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THE END!! Please visit us online at
http//www.ssel.montana.edu
For more information, questions, or comments,
contact Brian Larsen at larsen_at_physics.montana.ed
u