Demonstration of Autonomous Rendezvous Technology (DART) Inter-Agency AR&C Working Group May 22-23, 2002 Chris Calfee DART Project Manager 256-544-5788 Chris.Calfee@msfc.nasa.gov DART_NRL.ppt 5/23/02 DART_NRL.ppt

Agenda Introduction to DART Overview & Objectives Organization & Schedule DART Mission Description “Chaser” Vehicle - DART “Target” Vehicle - MUBLCOM Launch Vehicle - Pegasus Mission Operations - Flight & Ground System Test Summary Technology Readiness Levels Advanced Video Guidance Sensor (AVGS) 5/23/02 DART_NRL.ppt

Introduction to DART 5/23/02 DART_NRL.ppt

Project Overview DART Stands for: Demonstration of Autonomous Rendezvous Technology. DART Is a Flight Demonstration of the Hardware and Software Required to Autonomously Rendezvous with a Satellite (MUBLCOM) Currently in Orbit. Hardware: Advanced Video Guidance Sensor (AVGS) Heritage: VGS Developed by MSFC for Automated Rendezvous & Capture (AR&C) Project. Flown Twice on Board the Shuttle in an Open-Loop Mode AVGS is next generation system with advanced optics and electronics. Design goals: Longer Range, Lower Power and Weight Software: Based on Autonomous Rendezvous and Proximity Operations (ARPO) Algorithms Also Developed by NASA/MSFC. Both the AVGS and the ARPO Algorithms Will Become Embedded Technology on Board a Pegasus ELV, Making the DART Vehicle an Extension of the ELV Rather Than an Independent and Isolated Payload 5/23/02 DART_NRL.ppt

DART Objectives Primary Objective: Demonstrate in space Autonomous Rendezvous and Closed Loop Proximity Control Between a Chase Vehicle, DART, and a Passive, Cooperative Target Vehicle, MUBLCOM Raise AVGS/ARPO Technology Readiness Levels (TRL) from a 3/4 to a 7/8 Validate Ground Test Results of the AVGS and ARPO Algorithms Mission Objectives Transfer from parking orbit to MUBLCOM orbit Demonstrate Autonomous Proximity Operations While In the Vicinity of the Target Vehicle Using The AVGS V-Bar Approach and Stand-Off to 15 meters Collision Avoidance Maneuver (CAM) Docking Axis Approach and Stand-Off to 5 meters R-Bar Approach and Stand-Off to 50 Meters Autonomous Departure at End Of Mission 5/23/02 DART_NRL.ppt

Second Generation RLV Relevance The United States Has Successfully Performed Numerous Rendezvous and Docking Missions in the Past. The Common Element of All US Rendezvous and Docking is That the Spacecraft Have Always Been Piloted by Astronauts. Only the Russian Space Program Has Developed and Demonstrated a Routine Autonomous Capability. The European Space Agency and Japanese Are Developing Similar Technology. The DART Mission Provides a Key Step in Establishing an Autonomous Rendezvous Capability for the United States. All 2nd Generation Architectures and AAS Can Benefit From ARPO Technology. Even Manned/Piloted Vehicles Can Benefit Through Robust System Performance and Reduction of Potential Piloting Errors. 5/23/02 DART_NRL.ppt

DART Project Overview Schedule 5/23/02 DART_NRL.ppt

Project Team OSC - Overall Project Integration, Launch Vehicle Buildup & Test, AVGS Development, Test, Manufacture, & Integration, DART Buildup & Test, LV/DART Integration & Test, Launch & Mission Operations MSFC - Overall Project Management, AR&C Algorithms, AVGS S/W Development, Test Facilities & Support, Mission ops Support Draper – GNC System, Flight Vehicle S/W Advanced Optical Systems (AOS) - AVGS Design & Engineering Support KSC - Launch Services Support GSFC - IV&V 5/23/02 DART_NRL.ppt

2nd Generation RLV Organization Ext. Rqmts. Assessment Team Program Office Consultants E.G. F. Wojtalik, G. Oliver, B. Lindstrom Ext. Rqmts. Assessment Team Manager Deputy Quality Assurance Man. Chief Engineer Tech. Asst. ESA MSA Dennis Smith Dan Dumbacher C. Chesser Robert Hughes B. Morris Jill Holland Judy Dunn Procurement Procurement Legal Legal M. Stiles J. Seemann Program Planning and Control Sys. Engineering, & Integration Architecture Definition Program Integration & Risk Management Rose Allen, Manager Jerry Cook, Deputy Dale Thomas, Manager Chuck Smith, Deputy Steve Creech, Manager Danny Davis, Manager Bart Graham, Deputy Arch. Mgr. Arch. Mgr CTV AAS Bob Armstrong Charlie Dill Pete Rodriguez Steve Davis Chris Crumbly Airframe (LaRC) Operations (KSC) Flight Mechanics (MSFC) NASA Unique (JSC) Subsystems (GRC) IVHM (ARC) Manager LSE D. Bowles Julie Fowler Manager LSE Scott Huzar Manager LSE Scott Jackson Jack Mulqueen Manager LSE Dave Leestma Manager LSE Mike Skor Tom Hill Manager Asst. Mgr./LSE Bill Kahle Kevin Flynn Propulsion (MSFC) Flt. Demos & Exp. Integ. (MSFC) Manager Dep. Mgr. Lead Sys. Engr. Garry Lyles Steve Richards George Young Manager, acting Deputy Susan Turner 5/23/02 DART_NRL.ppt

Flight Demos & Experiment Integration Organization Flt. Demos & Exp. Integ. Susan Turner X-37 Jeff Sexton DART Chris Calfee Kistler K-1 Jimmy Lee 5/23/02 DART_NRL.ppt

Lead Software Engineer 2nd Generation RLV Program DART Organization DART Chris Calfee, Manager Lead Software Engineer Meg Stroud AVGS/Pegasus Lead Engineer Keith Higginbotham Asst. DART Manager Dexter Waldrep Lead Systems Engineer Mark Krome Contracts Earl Pendley Penny Battles Carol Greenwood S&MA Van Strickland Marcie Kennedy Business Jimmy Black Rich Leonard Louise Hamaker Pegasus Procurement Wanda Harding - KSC Flt. Demos & Exp. Integ. Susan Turner, Manager 2nd Generation RLV Program Dennis Smith, Manager 5/23/02 DART_NRL.ppt

OSC DART Organization Chart 5/23/02 DART_NRL.ppt

DART Mission Description 5/23/02 DART_NRL.ppt

Mission Overview Description of DART Vehicle Hydrazine Auxiliary Propulsion System (HAPS) 3 thrusters with 56.9 Kg (125 lbm) supply Delta-velocity, pitch and yaw attitude Pegasus Reaction Control System 6 nitrogen thrusters with dedicated 5.8 Kg (13 lbm) supply 3-axis attitude control during rendezvous and retirement Proximity Operations Reaction Control System 16 N2 thrusters with dedicated 29 kg (64 lbm) Tank 6-axis attitude and translational control during proximity operations Lithium Ion Battery Powered Avionics and Transient Power Busses UHF Antenna & Receiver System SIGI INS and Standalone GPS Navigation Solution Advance Video Guidance Sensor Maximum wet mass: 362.3 Kg (798 lbm) Assuming Pegasus XL launch to 500 km orbit at 97.7° inclination 5/23/02 DART_NRL.ppt

DART Mechanical Configuration Within Pegasus Stage 4 Avionics Structure is Top of HAPS Tank, Two RCS Tanks, SIGI Mostly Heritage Components and Layout for Stage 4 Within AVGS Bus Structure is Top of Proximity Ops RCS Tank Most New Components Mounted to Exterior of Cylindrical Structure, Forward AVGS Panel Pegasus Stage 4 AVGS Bus DART Expanded View Forward Looking Aft 5/23/02 DART_NRL.ppt

DART Mechanical Configuration, Cont MACH Batteries Proximity Ops RCS Tank, Tubing, Other Components HAPS Tank, Tubing, and Other Components DART Expanded View Aft Looking Forward 5/23/02 DART_NRL.ppt

Description of MUBLCOM Target Vehicle Launched in 1999 aboard a Pegasus Rocket Currently in a nearly circular orbit at 765 km Near-polar orbit with 97.7 inclination (nearly sun-synchronous) Gravity-gradient stabilized with momentum wheels for yaw control Long and short-range retroreflectors mounted ~parallel to velocity vector Far-range retroreflectors mounted along vehicle z-axis (nadir pointing) 5/23/02 DART_NRL.ppt

MUBLCOM 5/23/02 DART_NRL.ppt

Expanded View of Pegasus w/DART 5/23/02 DART_NRL.ppt

Mission Overview DART Launch Operations Overview Pegasus launch from Vandenburg AFB, CA on 4/15/04 Launch will deliver DART to a circular orbit at 500 Km altitude Ascending node and inclination matching those of the MUBLCOM satellite Hydrazine budgeted to allow Pegasus use of HAPS to correct launch dispersions ±30 second drop window assumed Minimizes ascending node errors Drop position accuracy relaxed to allow better drop time accuracy Launch opportunity every 3-5 days Phasing with MUBLCOM at launch constrained to less than 100° 5/23/02 DART_NRL.ppt

Mission Overview DART Rendezvous Operations Overview Early orbit checkout DART “catches up” to target vehicle at ~13 deg/hour Up to 7.5 hours spent in Phasing orbit 1 Hohmann transfer from 500 Km to ~755 Km altitude Rendezvous ends with DART 40 Km behind and 7.5 Km beneath MUBLCOM Rendezvous algorithms employ Pegasus PEG guidance PEG functionality extended with rendezvous phasing calculations Ascending node and inclination errors corrected during transfer using HAPS 5/23/02 DART_NRL.ppt

Mission Overview DART DRM Timeline Worst-case phasing at launch assumed 7+ hours in phasing orbit 1 Proximity operations begin 8 hours into the mission 8 hours in proximity operations Includes 3.5 hours of station keeping at various positions Retirement burn 16.5 hours into mission 7.5 hour time margin remaining 5/23/02 DART_NRL.ppt

DART Mission Profile Altitude(km) Far Range Mid Range Near Range GPS State Vector Differencing (Propagated Target State) GPS State Vector Differencing (Space-to-Space Target State) Proximity Sensor (AVGS) Communications Range (~100 km) Visible Range (~500 m) -3km 770 Target Vehicle Altitude(km) 755 Free Drift Start of Proximity Operations Orbit Transfer DART Retirement Burn Phasing 500 Launch Ascent Far Range Mid Range Near Range MET From L1011 Drop 00:09:00 08:00:00 11:00:00 16:30:00 Note: Altitude and Ranges are not to scale 5/23/02 DART_NRL.ppt

DART Proximity Operations Flight Profile Velocity Vector Orbital Motion 5 m MUBLCOM 300 m 1 Km 3 Km +VBar 50 m 15 m 100 m CAM 500 m 150 m Last HAPS Burn 40 Km behind 7.5 Km below End of Rendezvous Start of Prox Ops 300 m +RBar Baseline Profile Extended Profile Free Drift Retirement Burn Orbit Transfer 5/23/02 DART_NRL.ppt

DART-MUBLCOM Rendezvous Visual 5/23/02 DART_NRL.ppt

Mission Overview DART DRM Ground Station Coverage Three ground stations selected for telemetry coverage (VAFB for launch only) Poker Flats, Alaska McMurdo, Antarctica Svalbard, Norway Polar stations provide at least two telemetry downlink opportunities per orbit 5/23/02 DART_NRL.ppt

Psuedo Flight Code (CMDH, GN&C,Telemetry) DART Testing Desktop Simulation Performed at OSC Psuedo Flight Code (CMDH, GN&C,Telemetry) Hardware in the Loop – Static Flight Computer, GPS, INS, UHF, AVGS Hardware in the Loop – Dynamic Performed at MSFC Flight Robotics Lab Flight Computer, GPS, INS, AVGS 5/23/02 DART_NRL.ppt

Addressing SLI Program Goals: Increasing Technology Readiness Level Start: AVGS and ARPO at TRL 4 Finish: AVGS and ARPO at TRL 7/8

Addressing SLI Program Goals: ARPO Technology Readiness Levels 5/23/02 DART_NRL.ppt

Advanced Video Guidance Sensor (AVGS) 5/23/02 DART_NRL.ppt

(HEAD AND ELECTRONIC MODULE) OLD VGS SENSOR (HEAD AND ELECTRONIC MODULE) 5/23/02 DART_NRL.ppt

Proximity Sensor Comparison to Flight proven Unit +/-0.12 mm position, accuracy +/-0.10 mm/s velocity, accuracy +/-0.10 deg attitude, accuracy +/-0.30 cm position, accuracy +/-0.30 cm/s velocity, accuracy +/-0.25 deg attitude, accuracy 1-5 km range (spot mode) 300-500 m (full 6DOF) 150 m range Performance (Range & Target Specific) 8 watts power 60 watts power Single DSP board in sensor box Signal processing in separate VME Single box (20 lbs) (10” X 12” X 8”) 2 boxes (50 lbs total) Electronics 50 Hz update 5 Hz update Digital CMOS Camera (resolution 1000 X 1000) Analog Camera (resolution 640 X 480) Camera Lasers in optical path (Increased laser return) Laser not in optical path 4 lasers (reduced complexity and power) 8 lasers Optics AVGS VGS 5/23/02 DART_NRL.ppt

AVGS Functional Flow From “On-Orbit Testing of the Video Guidance Sensor” by Richard T. Howard, Thomas C Bryan, Michael L. Book, NASA/MSFC 5/23/02 DART_NRL.ppt

AVGS Design, Analysis and Test Brassboard Development Phase (6/1/01 - 1/28/02) Parts and Material Review EEE Parts Availability Outgasssing Radiation Environment Analysis Begin AVGS Software Development Evaluate Optics Performance Initial Prototype (IP) Development Phase (6/1/01 - 3/29/02) Power Supply Design Electronics Packaging Concepts Initial Structural Analysis Initial Electrical Analysis Initial Thermal Analysis Radiation Hardening Continue AVGS Software Development 5/23/02 DART_NRL.ppt

AVGS Design, Analysis and Test (Cont) Final Prototype (FP) Development Phase (4/1/02 - 10/18/02) 2 Prototype Units (Form, Fit & Function) FMEA Update Thermal Analysis Finalize Electronic Packaging Concepts Final Design for Radiation Environment Finalize Structural Analysis Finalize Electrical Analysis Begin AVGS Software functional Verification and Validation Qualification Unit Development Phase (9/23/02 - 5/29/03) Acceptance Testing (random vibe and thermal vac) Qualification Testing (EMI/EMC, Vibe, Shock, Thermal) AVGS Flight Load Software Delivery Flight Unit Development Phase (5/1/03 - 11/17/03) 3 Units Final AVGS Software Load Delivery (Jan04) 5/23/02 DART_NRL.ppt

New AVGS Initial Proto-Type Unit 5/23/02 DART_NRL.ppt

AVGS Development Breadboard Sensor Optics 5/23/02 DART_NRL.ppt

Addressing SLI Program Goals: DART-AVGS Technology Readiness Levels 5/23/02 DART_NRL.ppt

DART POP02 Summary by Center NOA $K 5/23/02 DART_NRL.ppt

Automated Rendezvous and Capture Documentation Technical Publications http://alternate.msfc.nasa.gov/AR&C/ a. Application of Neural Networks to Autonomous Rendezvous and Docking of Space Vehicles, Richard W. Dabney, AIAA Paper 92-1516, AIAA Space Programs and Technologies Conference, March 24-27, 1992, Huntsville, AL. b. United States Patent Number 5,109,345, CLOSED-LOOP AUTONOMOUS DOCKING SYSTEM, Richard W. Dabney and Richard T. Howard, April 28, 1992. c. A Plan for Spacecraft Automated Rendezvous, A. W. Deaton, J. J. Lomas, and L. D. Mullins, NASA TM-108385, October 1992. d. Guidance and Targeting Simulation for Automated Rendezvous, James J. Lomas, John M. Hanson, and M. Wade Shrader, AAS Paper 94-162, AAS/AIAA Spaceflight Mechanics Meeting, February 14 - 16, 1994, Cocoa Beach, FL. e. Guidance Schemes for Automated Terminal Rendezvous, John M. Hanson and Alva W. Deaton, AAS Paper 94-163, AAS/AIAA Spaceflight Mechanics Meeting, February 14 - 16, 1994, Cocoa Beach, FL. f. A Solution to the 3 Point Inverse Perspective Problem for Automated Rendezvous and Capture, Richard Dabney and Philip Calhoun, MSFC Memorandum ED13-94-21, September 30, 1994. g. Cargo Transfer Vehicle (CTV) Reference Design for Autonomous Rendezvous and Capture Simulations, Richard Dabney, MSFC Memorandum ED13-94-22 , October 26, 1994. h. MSFC-RQMT-2371 B, Automated Rendezvous and Capture (AR&C) System Requirements Document (SRD), Craig A. Cruzen, July 1, 1996. i. MSFC Flight Robotics Laboratory (FRL) Description, A World Class Simulation and Test Facility, Linda L. Brewster, Team Lead, Orbital Systems & Robotics Team, MSFC, November 1997. j. AR&C Ground Program System Test Plan, D. L. Kelley, Hernandez Engineering, December 19, 1997. k. MSFC Automated Rendezvous and Capture Simulation (MARCSIM) Description, Linda L. Brewster, Team Lead, Orbital Systems & Robotics Team, and Dave W. Allen, Team Lead, Simulation Software Team, MSFC, April 1998. l. Active Sensor System for Automatic Rendezvous and Docking, Richard T. Howard, Thomas C. Bryan, Michael L. Book, and John L. Jackson, Working Paper. m. Video Guidance Sensor Flight Experiment Results, Richard T. Howard, Thomas C. Bryan, and Michael L. Book, Working Paper. n. Automatic Docking System Sensor Analysis & Mission Performance, John L. Jackson, Richard T. Howard, Helen J. Cole, and Ronald A. Belz, Working Paper. 5/23/02 DART_NRL.ppt