Modeling Kinematic Cellular Automata Final Report NASA Institute for Advanced Concepts Phase I: CP-02-02 General Dynamics Advanced Information Systems Contract # P03-0984 Principal Investigator: Tihamer Toth-Fejel Consultants: Robert Freitas and Matt Moses April 30, 2004 1 Cover page: A Connector Subsystem of a KCA SRS (Kinematic Cellular Automata Self-Replicating System) preparing a part for assembly. Self-replicating systems could be used as an ultimate form of in situ resource utilization for terraforming planets. 2 Version: 4/30/2004 2:55 PM Table of Contents 1. ABSTRACT ..................................................................................................................................6 2. SUMMARY...................................................................................................................................7 2.1. TERMINOLOGY........................................................................................................................ 8 3. MOTIVATION AND JUSTIFICATION .....................................................................................8 3.1. WHY SELF-REPLICATION?....................................................................................................... 8 3.2. WHY NOT? ............................................................................................................................. 9 3.3. IS MACHINE SELF-REPLICATION POSSIBLE?.......................................................................... 10 3.4. ARE NANOSCALE SELF-REPLICATING MACHINES POSSIBLE?.................................................. 10 3.5. WHY NOT SELF-ASSEMBLY?................................................................................................. 11 3.6. WHY OR WHY NOT UNIVERSAL CONSTRUCTORS?.................................................................. 12 3.7. WHY THE “GENOTYPE + RIBOTYPE = PHENOTYPE” PARADIGM?............................................ 13 3.8. WHY MODULAR ROBOTS? .................................................................................................... 13 3.9. WHY KINEMATIC CELLULAR AUTOMATA MODULES?........................................................... 15 3.10. WHY BOTH MACRO AND NANO SCALE?................................................................................ 16 3.11. WHY NOW? .......................................................................................................................... 16 4. RELATED AND PREVIOUS WORK .......................................................................................16 5. BENEFITS AND APPLICATIONS ...........................................................................................20 5.1. PROGRAMMABLE MATERIALS............................................................................................... 20 5.1.1. Flow Mode...................................................................................................................20 5.1.2. Pixelated Mode.............................................................................................................22 5.1.3. Computation Mode.......................................................................................................22 5.2. SEVEN MAGNITUDES IMPROVEMENT .................................................................................... 23 5.3. INDUSTRIAL EXPANSION....................................................................................................... 24 5.4. SPACE EXPLORATION AND DEVELOPMENT ............................................................................ 24 5.4.1. Spin-offs.......................................................................................................................24 5.4.2. Orbital Operations .......................................................................................................25 5.4.3. Exploration ..................................................................................................................25 5.4.4. Base Establishment.......................................................................................................25 5.4.5. Terraforming................................................................................................................26 6. PROJECT GOALS.....................................................................................................................27 6.1. CHARACTERIZE SELF-REPLICATION...................................................................................... 27 6.2. QUANTIFY THE COMPLEXITY OF KCA SRS ........................................................................... 27 6.3. CONFIRM APPROACH............................................................................................................. 28 6.4. DESIGN A KCA SRS ............................................................................................................. 28 6.5. SIMULATE DESIGNS............................................................................................................... 28 7. PROJECT STRATEGY .............................................................................................................28 7.1. HYBRIDIZE TWO SELF-REPLICATION MODELS ........................................................................ 28 7.2. KEEP IT SIMPLE..................................................................................................................... 28 7.3. MAKE IT COMPLICATED ........................................................................................................ 28 7.4. REFINE APPROACH BY ATTEMPTING TO DESIGN..................................................................... 28 7.5. IMITATE COMPUTERS ............................................................................................................ 29 7.6. IMITATE BIOLOGY ................................................................................................................. 29 8. ACCOMPLISHMENTS .............................................................................................................29 9. CHARACTERIZING THE SELF-ASSEMBLY AND SELF-REPLICATION SPACE..........30 9.1. 137-DIMENSION DESIGN SPACE ............................................................................................ 30 9.1.1. New Dimensions...........................................................................................................32 9.2. LESSONS FROM BIOLOGY...................................................................................................... 33 3 10. QUANTIFYING THE COMPLEXITY OF KCA SRS..............................................................33 11. CONFIRMING OR REFUTING THE APPROACH................................................................34 12. PRELIMINARY DESIGN APPROACH. ..................................................................................35 12.1. LISTENING TO JOHN VON NEUMANN..................................................................................... 35 12.2. DR. FEYNMAN’S ERROR........................................................................................................ 35 12.3. THE ESSENTIAL RESEARCH PROBLEM ................................................................................... 37 13. HIERARCHY .............................................................................................................................37 13.1. COMPARING THE MOSES UCP AND THE KCA SRS................................................................ 39 14. SUBSYSTEMS DESIGN REQUIREMENTS............................................................................40 14.1. TRANSPORTER SUBSYSTEM................................................................................................... 40 14.2. CONNECTOR SUBSYSTEM...................................................................................................... 41 14.3. CONTROLLER SUBSYSTEM .................................................................................................... 43 15. CELL DESIGN REQUIREMENTS...........................................................................................47 15.1. STRUCTURE .......................................................................................................................... 48 15.2. ACTUATORS.......................................................................................................................... 49 15.3. SENSORS............................................................................................................................... 50 15.4. LOGIC UNIT .......................................................................................................................... 53 15.4.1. Instruction Set for Logic Unit .......................................................................................54 15.4.2. Logic Unit Trade-offs ...................................................................................................54 15.5. A ROUGH SPECTRUM OF ASSEMBLY METHODS ..................................................................... 55 15.6. SELF-ASSEMBLY IN MOLECULAR ELECTRONICS ................................................................... 56 16. FACET DESIGN REQUIREMENTS ........................................................................................60 17. SOFTWARE SIMULATION .....................................................................................................60 17.1. FACET ANIMATION ..............................................................................................................