ISS Flight Preparation

1
ISS Flight Preparation Hardware Status

• 08 July 2002
• Steve Sell (sell_at_payload.com)
• Stephanie Chen (chen_at_payload.com)

2
Agenda

• Payload Systems activities
• Mission description and logistics
• Integration activities
• Hardware build status

3
Payload Systems Activities
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Payload Systems Activities

• Design and construct SPHERES flight hardware
• Spheres
• Beacons
• Laptop hardware
• Conduct NASA International Space Station
  integration activities
• Safety review process
• Develop experiment procedures
• Conduct crew training
• Create Graphical User Interface (GUI)
• Conduct training of ISS crews
• Conduct hardware analyses and testing
• Safety verification analysis
• Flight certification testing
• Vibration
• EMI acoustic

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Mission Description and Logistics
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Major Components
Laptop Assembly
SPHERES Satellites
Ultrasound Beacon (5 Total)
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Hardware Components

• SPHERES consists of three satellites, eight
  inches in diameter
• Each satellite is self-contained with power (AA
  batteries), propulsion (CO2 gas), computers, and
  navigation equipment
• The satellites communicate with each other and an
  ISS laptop through a low-power wireless (RF) link
• Five ultrasound beacons located in the SPHERES
  work envelope act as a navigation system
• Each beacon is self-contained and uses two AA
  batteries
• A single beacon is approximately the size of a
  pager
• Operational volume is 6 x 6 x 6 (up to 10 x
  10 x 10 is possible)

Satellite
PADS beacon
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SPHERES Satellite
- X
Thruster
Ultrasonic receivers
CO2 tank
Adjustable regulator
Pressure gauge
Diameter 8 in (0.2 m)
Mass 7.85 lb (3.56 kg)
Thrust(single thruster) lt1 oz (0.2 N)
CO2 Capacity 6 oz (170g)
Z
Satellite body axes
- Y
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Operational Configurations

• Mode 1 Single satellite operations
• Long term station-keeping
• Minimum propellant maneuvers through
  pre-determined profiles
• Isolated multidimensional rotation,
  multidimensional translation
• Combined rotation translation
• Modes 2 and 3 Multiple satellite operations
  (two or three satellites)
• Docking
• Topological orientations
• Independent control
• Collision avoidance
• Hierarchical control (leader-follower)
• Distributed control (consensus)

Example configurations on the KC-135
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Typical Test Session
Each satellite calculates position from PADS
beacons
Transfer protocol/commandsvia wireless link to
satellites
ISS Laptop
Satellites perform formation flying maneuver
Control loop
Uplink protocols to OPS LAN prior to SPHERES ops
Appropriate thrusters fire
Data continuously downloaded to laptop
ISS Laptop
Downlink experiment data to ground after SPHERES
ops
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Typical Crew Operations
Take down and stow equipment
Unstow equipment
Setup test area (position US beacons)
Load tanks battery packs into satellites
Upload protocols from laptop to satellites
Run protocols from laptop
YES
NO
Test session over?
Satellites out of gas / power?
YES
NO
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SPHERES GUI (Sample)
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Mission Logistics

• SPHERES manifested on ISS for two increments
• Ascent flight ISS-12A.1 (STS-116, June 2003),
• Resupply flight ISS-13A (STS-117, September 2003)
  for replacement of consumables
• Descent flight ISS-15A (STS-119, January 2004)
• Operation Time
• Allocated 20 hours operation time (nominally
  spread over twelve sessions)
• Initial stowage requirements
• Three SPHERES satellites
• Five US beacons
• Laptop transmitter
• Consumables (CO2 tanks and battery packs)
• Spares TBD

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Stowage Allocation

• SPHERES is allotted 1.83 Middeck Locker
  Equivalents (MLEs) over ascent and resupply
  flights
• 1.5 MLE total on ascent flight
• 0.33 MLE total on one resupply flight
• Stowage allocated in Cargo Transfer Bags in the
  SpaceHab Module
• Possible to be stowed in any locker location

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Consumables

• Two approaches were taken to determine consumable
  estimates top-down (fixed stowage constraint)
  and bottom-up (fixed operation hours)
• CO2 tanks
• Part of the SPHERES mission investigates ways to
  minimize propellant usage
• This means that no exact number of tanks can be
  determined for total operations
• Initial estimate is 94 tanks
• Batteries
• Current estimate is 88 battery packs

Replacement CO2 tanks and battery packs
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ISS Equipment

• Workstation
• SPHERES will use Payload Equipment Restraint
  System (PERS) as a temporary workstation
• H-Strap interfaces with seat track provide two
  sides of velcro
• Attach laptop restraint for configurable laptop
  station
• Belly bag can be used to contain extra hardware
  (satellites) during test session

H-Strap
Belly Bag
Laptop Restraint
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ISS Equipment

• Laptop
• SPHERES GUI runs protocols from laptop
• Protocols uplinked to OPS LAN but no connection
  is required during testing
• Data stored on laptop until downlinked to ground
  following test session
• US beacons will attach to seat-track interfaces
  and/or handrail clamps
• Locations will be entered into laptop prior to
  operations

ISS Laptop
Handrail clamp
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Operational Scenarios

• SPHERES will operate in United States Operational
  Segments (USOS) only
• Ideal test area is 6 x 6 x 6
• Most likely will operate in 5 x 5 x 10, given
  ISS Node configuration

Envisioned operations in US Lab
Envisioned operations in ISS Node 1
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Integration Activities
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Integration Status Milestones

• Status
• Completed Phase II Safety Review Feb 2002
• Payload Integration Agreement baselined June 2002
• Preliminary draft of crew procedures submitted
  June 2002
• First test of positioning system in ISS node
  mockup conducted June 2002
• Upcoming milestones
• KC test of engineering Sphere scheduled July 2002
• October 2002 EMI and Vibe testing
• November 2002 Payload Training Dry Run
• November 14, 2002 Phase III Safety Review
• December 2002 Training Session 1
• January 31, 2003 Flight hardware delivery to
  JSC
• June 5, 2003 Launch on STS-116, 12A.1 to ISS

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Hardware Build Status
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Flight Hardware Status

• First unit build is 95 complete all components
  are in-house
• All structural components completed and assembled
• All avionics components completed and assembled
• All pressurized components installed
• Not all tubing and wiring has been routed
• Shell is prototype
• Anticipated 100 complete build in 1-2 weeks

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Structural Frame

• Aluminum structure
• Six laser cut rings
• Six sheet metal brackets
• Twelve cross members
• Provides stiffness and mounting points for
  satellite components

Metal bracket
Laser cut rings
Cross members
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Structure
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Electronics Board Locations

• Electronics are divided into two assemblies
• PADS and computing
• Signal processing
• Computing
• Propulsion and power
• Thruster valve control
• Power distribution

Propulsion and power boards
PADS and computation boards
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Assembly - Avionics
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Structural Assembly Stage One

• Electronics assemblies
• Electronics are assembled inside a partial
  structure and wired
• Avionics can be tested on the bench top

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Structural Assembly Stage One
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Structural Assembly Stage Two

• Remaining sheet metal brackets are attached
• Battery packs and regulator/tank assembly can
  then be installed

Mounting brackets
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Structural Assembly Stage Two
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Structural Assembly Stage Three

• Propulsion system tubing is routed
• Tubing is assembled prior to final structural
  element placing
• Manifolds distribute gas from CO2 tank to twelve
  thruster nozzles

Tubing manifolds
Thrusters
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Structural Assembly Stage Three
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Full Assembly

• Satellite is fully functional without shell

Ultrasonic receiver
Thruster
Aluminum frame
Pressure gauge
CO2 tank
Battery pack
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Full Assembly
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External Shell Structure

• Two part shell assembly
• Constructed of polycarbonate
• Secured with four fasteners per side
• Hinged door for battery access
• Cut-outs for thrusters and sensors

Polycarbonate half shell
Attachment screw
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Schedule Milestones

• July 29 - August 3, 2002 KC-135 Flights
• October 2002 EMI and Vibe testing
• November 2002 Payload Training Dry Run
• November 14, 2002 Phase III Safety Review
• December 2002 Training Session 1
• January 31, 2003 Flight hardware delivery to
  JSC
• June 5, 2003 Launch on STS-116, 12A.1 to ISS