SPHERES ISS Flight Preparation & Hardware Status 08 July 2002 Steve Sell Stephanie Chen

SPHERES 2 Agenda Payload Systems activities Mission description and logistics Integration activities Hardware build status

SPHERES 3 Payload Systems Activities

SPHERES 4 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

SPHERES 5 Mission Description and Logistics

SPHERES 6 Major Components SPHERES Satellites Laptop Assembly Ultrasound Beacon (5 Total)

SPHERES 7 Hardware Components SPHERES consists of three “satellites”, eight inches in diameter –Each satellite is self-contained with power (AA batteries), propulsion (CO 2 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) PADS beacon Satellite

SPHERES 8 SPHERES Satellite + Z - Y - X Ultrasonic receivers CO 2 tank Adjustable regulator Pressure gauge Thruster Satellite body axes Diameter8 in (0.2 m) Mass7.85 lb (3.56 kg) Thrust (single thruster) <1 oz (0.2 N) CO 2 Capacity6 oz (170g)

SPHERES 9 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

SPHERES 10 Satellites perform formation flying maneuver Uplink protocols to OPS LAN prior to SPHERES ops Each satellite calculates position from PADS beacons Appropriate thrusters fire Transfer protocol/commands via wireless link to satellites Data continuously downloaded to laptop Downlink experiment data to ground after SPHERES ops Control loop ISS Laptop Typical Test Session

SPHERES 11 Typical Crew Operations Load tanks & battery packs into satellites Upload protocols from laptop to satellites Run protocols from laptop Unstow equipment Satellites out of gas / power? Setup test area (position US beacons) NO YES Test session over? YES NO Take down and stow equipment

SPHERES 12 SPHERES GUI (Sample)

SPHERES 13 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

SPHERES 14 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

SPHERES 15 Consumables Two approaches were taken to determine consumable estimates: top-down (fixed stowage constraint) and bottom-up (fixed operation hours) CO 2 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 CO 2 tanks and battery packs

SPHERES 16 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 Laptop Restraint Belly Bag

SPHERES 17 ISS Laptop Handrail clamp 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

SPHERES 18 Operational Scenarios Envisioned operations in ISS Node 1 Envisioned operations in US Lab 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

SPHERES 19 Integration Activities

SPHERES 20 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

SPHERES 21 Hardware Build Status

SPHERES 22 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

SPHERES 23 Structural Frame Aluminum structure –Six laser cut rings –Six sheet metal brackets –Twelve cross members –Provides stiffness and mounting points for satellite components Laser cut rings Cross members Metal bracket

SPHERES 24 Structure

SPHERES 25 Electronics Board Locations Electronics are divided into two assemblies –PADS and computing Signal processing Computing –Propulsion and power Thruster valve control Power distribution PADS and computation boards Propulsion and power boards

SPHERES 26 Assembly - Avionics

SPHERES 27 Structural Assembly Stage One Electronics assemblies –Electronics are assembled inside a partial structure and wired –Avionics can be tested on the bench top

SPHERES 28 Structural Assembly Stage One

SPHERES 29 Structural Assembly Stage Two Remaining sheet metal brackets are attached –Battery packs and regulator/tank assembly can then be installed Mounting brackets

SPHERES 30 Structural Assembly Stage Two

SPHERES 31 Structural Assembly Stage Three Propulsion system tubing is routed –Tubing is assembled prior to final structural element placing –Manifolds distribute gas from CO 2 tank to twelve thruster nozzles Tubing manifolds Thrusters

SPHERES 32 Structural Assembly Stage Three

SPHERES 33 Full Assembly Satellite is fully functional without shell Aluminum frame CO 2 tank Thruster Pressure gauge Battery pack Ultrasonic receiver

SPHERES 34 Full Assembly

SPHERES 35 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 Attachment screw Polycarbonate half shell

SPHERES 36 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