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Cornell University Ithaca, New York 14650 JOSE - JUPITER ORBITING SPACECRAFT

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Cornell University Ithaca, New York 14650 JOSE - JUPITER ORBITING SPACECRAFT N T Z 33854 C *?** IS81 1? JOSE - JUPITER ORBITING SPACECRAFT: A SYSTEMS STUDY Volume I '>•*,' T COLLEGE OF ENGINEERING Cornell University Ithaca, New York 14650 JOSE - JUPITER ORBITING SPACECRAFT: A SYSTEMS STUDY Volume I Prepared Under Contract No. NGR 33-010-071 NATIONAL AERONAUTICS AND SPACE ADMINISTRATION by NASA-Cornell Doctoral Design Trainee Group (196T-TO) October 1971 College of Engineering Cornell University Ithaca, New York Table of Contents Volume I Preface Chapter I: The Planet Jupiter: A Brief Summary B 1-2 r. Mechanical Properties of the Planet Jupiter. P . T-fi r> 1-10 F T-lfi F T-lfi 0 1-29 H, 1-32 T 1-39 References ... p. I-k2 Chapter II: The Spacecraft Design and Mission Definition A. Introduction p. II-l B. Organizational Structure and the JOSE Mission p. II-l C. JOSE Components p. II-1* D. Proposed Configuration p. II-5 Bibliography and References p. 11-10 Chapter III: Mission Trajectories A. Interplanetary Trajectory Analysis .... p. III-l B. Jupiter Orbital Considerations p. III-6 Bibliography and References. p. 111-38 Chapter IV: Attitude Control A. Introduction and Summary . p. IV-1 B. Expected Disturbance Moments M in Interplanetary Space . p. IV-3 C. Radiation-Produced Impulse Results p. IV-12 D. Meteoroid-Produced Impulse Results p. IV-13 E. Inertia Wheel Analysis p. IV-15 F. Attitude System Tradeoff Analysis p. IV-19 G. Conclusion P. IV-21 References and Bibliography p. TV-26 Chapter V: Propulsion Subsystem A. Mission Requirements p. V-l B. Orbit Insertion Analysis p. V-5 C. Candidate Propulsion Systems p. V-7 D. Solid Propellant Motors Investigation. p. V-8 E. Fluid Propulsion Systems Investigation p. V-ll F. Conclusions and Recommendations p. V-15 Bibliography and References p. V-l6 Table of Contents, cont. Chapter V.I: Science Experiments A. Introduction p. VI-1 B. The Science Payload p. VI-1 References p. VI-33 Chapter VII Telecommunications and Data Processing Systems A. Design Philosophy p. VII-1 B. System Description.. p. VII-3 Bibliography and References ....... p. VII-22 Chapter VIII: On-Board Power Supply A. Introduction. ., p. VIII-1 B. Space Power Subsystems p. VIII-2 C. RTG Design Considerations p. VIII-T D. Power Supply Reliability p. VIII-13 E. Power and Voltage Levels p. VIII-1? References p. VIII-25 Chapter IX: Spacecraft Structure and Environmental Design Considerations A. Factors Affecting General Configurations p. IX-1 B. Preliminary Design Decisions p. IX.-h C. Major Subsystem Design p. IX-9 References ..;... p. IX-57 Volume II Appendices Appendix A 1975-1985 Interplanetary Trajectory Parameters Appendix B JOSE Subprograms Descriptions Appendix Cl Selected Typical Trajectory Characteristics for the Attitude Control Study Appendix C2 Interplanetary Impulse Requirements - Gas Jet System Design Appendix C3 Inertia Wheel Formation Appendix CU Z-Axis Angular Velocity Tradeoff Analysis Appendix D Trajectory Analysis Appendix E Motor Investigation Appendix F Orbiter Zeodesy Table of Contents, cont. Volume II Appendices Appendix Fl General Orbital Secular Rates of Motion Due to the Central Gravity Term and the Second and Fourth Degree Zonal Harmonics Note (i = 0°) Appendix F2 Derivation of the Lagrange Equations of Orbital Motion for the Equatorial Case Appendix F3 Equatorial Secular Orbital Rates of Motion Due to the Central Gravity Term and the Second and Fourth Degree Zonal Harmonics (i = 0°) Appendix Fl| Elements of the Coefficient Matrix G for the Short Term Periodic Perturbations of an Equatorial Orbit Appendix F5 The Integral Functions h of the Periodic Orbital Rates of Motion Appendix G Determination of Dovnlink Power-Gain Product Authors Charles K. Paul Chapters I, II, III, IV, VI. Appendices A, B, Cl, C2, C3, CU, F, Fl, F2, F3, Fl*, F5. Thomas R. McDonough Chapters I, II, VI. Appendices F, Fl, F2, F3, FU, F5, Alan W. Schorr Chapters II, VIII, IX. John L. Matilaine Chapters II, VII. Appendix G Phillipe L. Lamy Chapters II, V. Appendices D, E. Michael H. Redlin Chapters II, IX. Preface The following report is the result of an educational experiment con- ducted at Cornell with the support of the NASA Office of University Affairs. The intent of the experiment was to determine whether meaningful doctoral design work in a systems engineering context could "be conducted in the university environment. In addition to Cornell, Purdue, Georgia Tech, Kansas State, and Stanford were involved in similar programs. The schools named are scattered both regionally and philosophically. The modes of approach devised by the several schools have differed. At Cornell the mode has involved a central project with the individual students assuming responsibility .for a major subsystem. In the majority of cases students have been able to satisfy the thesis requirement for the doctorate by an in-depth study of an aspect of their project responsibility. Student interest has been high from the outset of the program and in the majority of cases faculty have willingly become involved. Although the number of students in this and following groups is small, sufficient have presented theses to their special committees successfully so that there is little doubt that design oriented or mission directed thesis work is judged acceptable from an academic point of view. The personnel and faculty have varied with time. As in industry a certain turnover occurs as life goals change. A listing of personnel engaged in the project and areas of concern follow: Personnel NASA Supported Charles K. Paul - Civil Engineering Faculty Advisor: Professor A. McNair Thesis: "Attitude Control, Trajectory Analysis, and Science Objectives of a Jupiter Orbiting Spacecraft" Doctoral Degree Received: June 1970 Presently on Faculty'of Division of Basic Studies, Cornell University. Thomas R. McDonough - Astronomy Faculty Advisor: Professor N. Brice Thesis: "The Interaction of the Solar Wind with the Interstellar Medium". Doctoral Degree Expected: February 1972 'Presently a Graduate Student at Cornell University. Alan W. Schorr - Mechanical Engineering Faculty Advisor: H. N. McManus, Jr. Thesis: "The Design, Modeling*, and Optimization of a Space-Oriented , •'•;• Radioisotope Thermoelectric Pover Supply" Doctoral Degree Received: September 1971 Robert L. Ryan. - Electrical Engineering Left the program after one year to attend Harvard Business School. John L. Matilaine - Electrical Engineering Faculty Advisor: Professor N. Brice Does not intend to complete doctoral work — changed objective. Presently employed by radio station WBR, Ithaca, N. Y. Affiliated (Non-NASA Supported) Charles H. Acton, Jr. - Electrical Engineering Faculty Advisor: Professor N. Vrana Project work on Galilean moons of Jupiter. M.Eng. (Electrical) Degree: February 1970 Presently at NASA-JPL, Pasadena, California Phillipe L. Lamy - Aeronautical Engineering Thesis Advisor: Professor H. N. McManus, Jr. Thesis: "Design Criteria, Investigation and Selection of a Jupiter Orbiter Propulsion System" M.S. Degree: September 1971 Presently pursuing doctoral work in the Department of Theoretical and Applied Mechanics, Cornell University. • Michael H. Redlin - Mechanical Engineering Faculty Advisor: Professor R. M. Phelan Presently on active duty with the United States Navy. Will complete doctoral studies after service. From the writer's point of view the experiment has been interesting and instructive. The program at Cornell has answered affirmatively the pedagogical question originally posed. H. N. McManus, Jr. Professor of Mechanical Engineering Program Director iii Chapter I: The Planet Jupiter: A Brief Summary A. Introduction Jupiter, the largest planet of this solar system, with a mass more than twice the combined masses of all the other planets, is the fifth planet in distance from the sun. Jupiter is the first of the major planets encountered after passing through the asteroid belt from the sun. The remaining major planets are Saturn, Uranus, and Neptune. These major planets are generally classified as such because of their relatively large diameters o (50,000 to 1^0,000 km.); low densities (0.7 to 1.7 gm/cm ); and extensive, optically thick atmospheres containing hydrogen, helium, methane, and ammonia as well as other gases in lower abundance. In contrast to these major planets are the four terrestrial planets, i.e., Mercury, Venus, Earth, and Mars, having small diameters (5,000 to 13,000 km.); high densities (U.2 to 5-5 gm/cm ); relatively thin atmospheres with a known planetary solid surface. Thus, the understanding of the origin of the solar system and eventually the universe necessitates the understanding of the differences between major and terrestrial planets; and Jupiter, the major planet closest to Earth, is first in line to be investigated by an interplanetary spacecraft. Other features unique to Jupiter are of course its famous Red Spot, the South Tropical Disturbance, and other atmospheric phenomena, and twelve associated satellites, four of which possess retrograde orbits. Also, there is a likelihood that there exist zones within Jupiter's atmosphere having physical and chemical properties conducive to the creation and harboring of life forms. It can be argued that, accepting present theories of atmospheric constituents and energy exchanges necessary for the creation of simple life forms, Jupiter's atmosphere may very well be the most ideal location for the creation of life forms in this solar system, including Earth with its present gas abundances. It should be remarked that much of the information contained in this chapter, i'.e., the present Jupiter state-of-knowledge
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