ORBITAL EXPRESS Space Operations Architecture Program 17 th Annual AIAA/USU Conference on Small Satellites August 12, 2003

Transcription

1 ORBITAL EXPRESS Space Operations Architecture Program 17 th Annual AIAA/USU Conference on Small Satellites August 12, 2003 Major James Shoemaker, USAF, Ph.D. DARPA

2 Orbital Express Space Operations Program Goals Demonstrate the technical feasibility of on-orbit satellite servicing Refueling Pre-Planned Product Improvement (P3I) Electronics Upgrades Operation with micro-satellites Demonstrate (analytically) the utility of on-orbit servicing Establish a non-proprietary satellite-to-satellite interface standard Obtain affordability data supporting transition decisions Two Satellite Demonstration Program Optimization of satellite coverage Counter adversary scheduling (D&D) / increased survivability Rapid deployment of new technology on orbit Supporting infrastructure for military operations in space 2

3 Orbital Express On-Orbit Servicing System Concept Target Satellite Orbit ASTRO Transfer Orbit Consumables Holding Orbit ASTRO Autonomous Space Transfer & Robotic Orbital Servicer On-Orbit Servicing Enables Operational Flexibility / Survivability Injection of New Technology Satellite Lifetime Extension Fuel and Upgraded Avionics MicroSat Launch on Demand Refuelable/ Upgradeable Spacecraft 3

4 Operational CONOPS Overview Mated Operations Prox Ops and Capture 5 6 Release & Separation 7 8 Loiter Orbit NEXTSat Near Field Rendezvous 4 Deploy/ Retrieve Microsat 9 10 Rend & Capture CSC ASTRO Far Field Rendezvous 3 11 Mated Ops at CSC 12 Disposal CSC 2 Launch 1 Pre-launch / Mission Planning CONOPS is Based on a Standard Set of Mission Procedures and Servicing Elements for all Missions Each mission / client has an optimum combination of steps and elements 4 Levels of Supervised Autonomy (1) Require ground approval or data up-link before execution (2) Allow ample time for ground override before the onboard system automatically carries out a command (3) Run autonomously, sending commands to the ground for occasional verification (4) Fully automate operations, with ground analysis only when a problem occurs 4

5 Demonstration Overview The demonstration test plan on the next chart consists of 20 scenarios: Scenario 0: After deployment from the launch vehicle, the vehicles remain in the mated launch configuration and will perform several fluid and ORU transfers Scenario 1: The vehicles will separate and move to a safe position for independent vehicle checkout and initialization Scenarios 2-7: ASTRO will perform proximity operations and capture from 10m, 30 and 60m, and perform several fluid and ORU transfers when mated Scenarios 8-15: ASTRO will perform near field rendezvous from 1 km, 7 km and 200 km, perform elliptical and circular fly-arounds, approach and capture, and perform several fluid and ORU transfers Scenario 16: ASTRO will perform far-field rendezvous from 1000km, approach and capture Scenarios 17-20: Reserved scenarios 5

6 Demonstration Test Plan Test Rendezvous Prox Ops Capture Unmated Mated Scen Direction Max Rng Flyrnd Max Rng Apprch Contin Mnvr Cmd Type Lite Hr Min m/s kg ORUs Fluid Days kg C/O m Sol Inrl - Grd Direct D m Sol Inrl - XL Fr-Flr N m Sol Inrl - XL Fr-Flr N m Sol Inrl Bkout Grd Direct N m Sol Inrl - Grd Direct D m Sol Inrl - XL Direct D Flyrd 1x 120 x 60 m Sol Inrl 30 m Hold Grd Direct D Flyrd 1x 100 x 100 m Sol Inrl - XL Direct D Behind 1 km Direct 120 to 60 m Sol Inrl - Grd Direct D In Front 1 km Flyrd 2x 100 x 100 m Sol Inrl Brkout 8-30 Grd Direct N Behind 7 km Flyrd 1x 120 x 60 m Sol Inrl - XL Fr-Flr N In Front 7 km Flyrd 3x 100 x 100 m +V-Bar - XL Fr-Flr N Behind 200 km Direct 120 to 60 m Sol Inrl 4 km Hold XL Direct D In Front 200 km Direct 120 to 60 m -R-Bar - Grd Direct D Behind 1000 km Direct 120 to 60 m Sol Inrl - XL Fr-Flr N Reserved for Scenario Repeat (Duration and Fuel Based on Scenario 7) Reserved for Scenario Repeat (Duration and Fuel Based on Scenario 8) Reserved for Scenario Repeat (Duration and Fuel Based on Scenario 9) Reserved for Scenario Repeat (Duration and Fuel Based on Scenario 10) Mated Reboost All Engine Canting, Dispersions, Uncertainties (30%) Total Defined: 132 Days 102 kg Fuel Total Undefined: 233 Days 42 kg Fuel Total: 365 Days 144 kg Fuel (FTAPS Usable) Demonstration Test Plan Summary (Revision I) 6

7 Typical Body Approach Profile Solar Inertial Approach 60 ASTRO Relative Altitude (m) Approach Init (AI) Capture Rng=60 m 2 Flyaround Init (FI) Rng=.1 m 20 Rng=120 m 7 Capture SK Init Rng=.1 m +V-Bar 6 4 Final Appr Init (FAI) 30 m Cont. SK Rng=10 m Rng=30 m 20 1 Prox Ops Init (POI) 5 10 m SK Init Rng=120 m 40 Rng=10 m R-Bar ASTRO Downrange Distance (m) 7

8 NEXTSat Space Vehicle Overview Rendezvous/Prox Ops AIDS Passive docking sensor Retro reflectors Grapple fitting for alternate docking Crosslink Antenna Antenna for interface ASTRO Servicing Interfaces Starsys passive latch Triangular wedge design guides and positions active side arms Kinematic mounting points Electrical coupler interfaces Fluid / gas transfer coupling / carrier Sealing design Quick disconnect NEXTSat/CSC Payload Separation Ring Transfers launch loads Debris control envelope Clearance for ASTRO docking RS-300 Bus ORU s and Storage Bays Arm access to bays Lithium - ion battery Flight Computer Kinematic mount Positive latch RS300 Bus Mature bus design supports payload Fluid Transfer Module Modular transfer system 34 kg fuel tank capacity Module contains fluid transfer components, support hardware, plumbing and control electronics module 8

9 Demonstration ASTRO Space Vehicle Overview Spacecraft Processing Open architecture and modular design RAD hard 750 power PC processor 1394 Fire wire plug & play embedded network Sun safe mode Distributed Telemetry Data Acquisition SGLS & TDRSS Command and Control Links Electrical Power DeployableGimbaled Solar Array(s) ~7.1 sq m, 535W Load 1200 W (EOL) Li-Ion Battery, 2x33 A-hr Robotic Arm MDR arm and end effector ORU Transfers using Robotic Arm Maximum reach ~3.3 m Camera on end effector Propulsion & Fluid Transfer Accommodations 72 kg Mono hydrazine based on TRW heritage 37 kg Propellant Xfr Quantity ~186 m/sec delta-v unmated, plus 1400 hrs mated Capture and propellant transfer mechanisms Aft View Top View Attitude Determination, Control & Navigation Star Camera & GPS Receiver Inertial Measurement Unit & Sun Sensors (4X) Structures & Mechanisms Low cost Al honeycomb panel construction w/ central cylinder backbone Load and stiffness for mated ASTRO/NEXTSat launch config. Built-in thermal radiators Communications AFSCN SGLS & TDRSS S-Band Inter-element Crosslink Subsystem (part of PL Transfer Subsystem) Encryption/Decryption Rendezvous/Prox Ops Boeing RPO suites + AVGS sensor (MSFC provided) RPO/mission processor, 750 power PC RPO/cameras, 3 Vis cameras, IR Camera RPO/long range LIDAR 9

10 Operational System ASTRO Spacecraft Bus RPO Sensors Cargo Section Remote Manipulator Arm and Support Assembly Capture System Module 10

11 Summary A comprehensive on-orbit servicing architecture enables: Ready availability of fuel, providing the tactical agility required for a wide range of current and emerging missions Modular replacement function leading to multi-mission capability and life extension Bus functions and orbit transfer service for microsatellite operations Reduced mission risk through proven on-orbit infrastructure We are also exploring NASA applications and civil missions Commercial implications (e.g. lower insurance costs with serviceability) 11