Transcript Contractor five - Texas A&M University

CHRIS CEDERBERG
DANIEL CHARLES
JOSEPH DUGGAN
JOSHUA KINSEY
HAYLIE PETERSON
HOPE RUSSELL
PATRICK WHALEN
TAYLOR YEARY
Overview
Design Evolution
 Chosen design
 Formation
 Power
 Guidance, Navigation and Control
 Image Processing
 Telecommunications
 Advantages

Light Optics Designs
EXTENSION ARM
JACK-IN-THE-BOX
EXTENDOR
SLEEVE
Optics Design
FLOWER PATCH
UMBRELLA
PHOTON SIEVE
Selected Optical Design
VEGETABLE PATCH
Selected Optical Design
Telescope Deployment
Proposed Design
Formation
Design Considerations:
- CIRCLE
- CONCENTRIC CIRCLE
- Y-SHAPE
- PEACE SIGN
- CLOUD
Discarded Ideas
SMILEY FACE
STAR
LINE
SQUARE
POUND SIGN
MONEY SIGN
BLOCK ‘T’ (A&M)
FORMATION
NIKE swoosh
ARROW
ASTERISK
V-SHAPE
TRIANGLE
PLUS SIGN
Formation
Final Choice: Cloud
Benefits
-
Does not require strict shape
-
GPS will give position of each satellite
-
Allows for more error in deployment
-
Is variable size to accommodate different
shadow sizes
-
Requires enough satellites to obtain sufficient
resolution in any axis
Requirements
-
Wmin
Wmax
Algorithm to maintain relative cubesat
positions
-
Center Communication Satellite serves
as origin of cloud
-
Maintain certain min/max radius around
each satellite
-
Bound max radius within shadow size
-
Higher distribution in center circle
Optical Satellite
Communication Satellite
Power
POWER
Photovoltaic
Pros:
Nuclear Reactor
Cons:
-High specific power
-Affected by
-Unlimited power
orientation
-Relatively
-Low maneuverability
inexpensive
Static
Thermionic
Thermoelectric
Pros:
Cons:
-Low degradation
-Low specific power
-Unaffected by sun’s
-Low fuel availability
position
-High power range
-Very high nuclear
threat
Guidance, Navigation and Control

Design Tree
 List of common satellite sensors and actuators
 Green color denotes hardware we have selected
Sensors
GPS
Sun
Sensors
Horizon
Sensors
Magnetometer
Gyroscope
Actuators
Magnetorquers
CMGs
Reaction
Wheels
Thrusters
Star
Tracker
Guidance, Navigation and Control

Orbit Position
 GPS receiver

Sun Sensor
Attitude Determination
 Requires 2 known vectors for attitude estimation
 Sun Sensors and Magnetometer
Magnetometer
○ Sun and magnetic field vectors in body frame
 Gyroscope to measure angular rates

Attitude Control
Gyroscope
 Orient cubesat and dampen disturbances
 Reaction Wheels
○ Primary attitude control
 Magnetorquers
Magnetorquer
○ Secondary attitude control
○ Momentum dumping for reaction wheels
Reaction Wheel
Guidance, Navigation and Control



Maintaining ‘Cloud’ formation

Algorithm to detect when thrust is required

Small bursts of thrust for corrections
VACCO Micro-Propulsion System (MiPS)

Contains 5 thrusters and propellant

Isobutane propellant
Attitude control system will need to counteract
unwanted torques produced by MiPS
VACCO MiPS
Image Processing/Computing
Data Handling

Central onboard processing
 Image processing
 Calculate asteroid trajectory
Send all raw data to ground for
computation
 Relay raw data through central satellite
 Algorithm to identify useful information

Telecommunications
Ground Stations and Data Dissemination Architecture

Primary ground station
 College Station, TX

Secondary ground station in order to
maintain extended time of L.O.S. with
array.
 Saudi Arabia

Data dissemination architecture
 Broadcast via Relay Satellites (RS)
○ RS must communicate with approximately 1/3 of
local cubeSats in array and relay data to ground
stations
Operating Frequency Decision Tree
Operating
Frequencies
Option 1
Uplink
VHF
- Lower
bandwidth for
easier
transmission of
smaller data
Option 2
Downlink
S-Band
- Joint
configuration
with UHF not
available
UHF
- Higher
bandwidth for
faster
transmission of
large data
- less chance of
interference
Uplink/Downlink
UHF
VHF
Deployable Antenna Systems

First Design Consideration
 “Inflatable” Antenna Systems
○ More than what we need and not fully proven methods.
High Gain S-Band Boeing System
MIT Sublimating Powder
Inflatable Antenna
Deployable Antenna Systems

Second Design Consideration
 Deployable Tape Spring Antennas
○ Up to four monopole antennas with various
configurations (VHF/UHF)
Telecommunication System Overview

Frequencies
 UHF Downlink
 VHF Uplink

RS Antennas
 4 UHF Monopoles*
 2 VHF Monopoles*

Optical Sat Antennas
 1 UHF Monopole*
 1 VHF Monopole*

Transceiver
 ISIS UHF Downlink/VHF Uplink Full
Duplex Transceiver
*Number of monopole antennas on each sat might
vary depending on requirements and further
investigation.
Telecommunication System Overview
Ground Station

Requirements






UHF and VHF Antennas
Elevation and Azimuth Rotators
Satellite Tracking Software
Ability to control remotely
Compact/Affordable
Existing Ground Station “Kit”
 Innovative Solutions in Space (ISIS) “Full
Ground Station Kit for VHF/UHF” meets
above requirements.
Summary
External Cassegrain “Vegetable Patch”
Telescope
 Cloud Formation
 Solar Panels for Power
 GPS, Sun Sensors, Gyroscope and
Magnetometer for Navigation
 Image Processing at Ground Station
 VHF Uplink, UHF Downlink with
deployable Tape spring antennas

Questions?