Current Trends in Spaceflight Research: From Galileo to Cassini and Beyond Mrinal Kumar Assistant Professor, MAE 306 MAE-A mrinalkumar@ufl.edu http://www.mae.ufl.edu/~mrinalkumar Presentation Outline o PAST o PRESENT (including my research interests) o FUTURE Presentation Outline o PAST • • Centuries ago Decades ago o PRESENT (including my research interests) o FUTURE Many names, but not for the same thing… • Celestial Mechanics: motion of celestial bodies • Astrodynamics: astron + dynamics • Orbital Mechanics: mechanics in orbit • Space Dynamics: motion in space Old school; only natural bodies like stars, planets, asteroids More contemporary; study motion under gravity in general, including natural objects and especially, spacecraft • Astronautics: astron + nauticus: navigation through the stars www.nasa.gov • Astronomy: astron + nomos: related field, observation of stars etc. www.fascinatingly.com IAU www.gpsmagazine.com The Cradle of Mathematics • Geometrical Analysis: Tycho Brahe, Johannes Kepler • Calculus: Isaac Newton, Gottfried Leibniz • Calculus of Variations: Leonhard Euler, Joseph Lagrange, PierreSimon Laplace, William Rowan Hamilton • Vector analysis: Josiah Gibbs • Linear Algebra: Arthur Cayley • Numerical methods: Carl Friedrich Gauss, numerous others Long Long Ago: A History of Celestial Mechanics 1700’s Pre- 1700’s Newton Euler Galileo Copernicus Brahe Kepler Gauss Galileo Copernicus Brahe Kepler calculus (simultaneously /w Leibniz) law of universal gravitation laws of motion Principia Mathematica calculus of variations, PDE theory rigid body dynamics fluid mechanics author of numerous papers probability theory system of equations boundary value problems Disquisitiones Aritmeticae Theoria Motus “pauca sed matura” A While Ago: A History of Celestial Mechanics 1800’s Jacobi Laplace calculus of variations rigid body dynamics special functions and PDEs special functions and PDEs linear equations potential theory Hamilton Lagrange calculus of variations analytical mechanics Mecanique Analytique calculus of variations canonical equations of mechanics quaternions, rotational dynamics Problems of Interest: Two examples The Lambert’s Problem Kepler’s Time Equation Not So Long Ago: Celestial Mechanics Late 1800’s – Early 1900’s Gibbs Cayley vector analysis matrix theory thermodynamics matrix analysis differential equations linear algebra Since 1900’s No giants in particular, but numerous smaller contributions leading to development of the field Numerical methods Estimation theory: Kalman Filter Optimization theory and control Einstein quantum mechanics general and special relativity modern physics Trajectory design and Navigation Sensor technology Contemporary Celestial Mechanics (USA) UCLA: Sam Herrick (1911 – 1974) MIT: Richard Battin; Jonathan How Boulder: George Born, Robert Culp; Dan Scheeres, Hanspeter Schaub Purdue: James Longuski Kathleen Howell Texas A&M: John Junkins (Sam Herrick’s student at UCLA) Daniele Mortari, Kyle Alfriend Malcolm Shuster: Last academic appointment at UF Some Current Problems of Interest o Deep Space Exploration/Advanced Mission Design o Aerocapture and Aerobraking Technologies o Formation Flying: Spacecraft Constellations o Novel Methods of Control o Space Debris Management o Uncertainty Handling in Space Some Current Problems of Interest Deep Space Exploration/ Advanced Mission Design: www.nasa.gov Explore: Gravity assists, Patched conics Some Current Problems of Interest Deep Space Exploration/ Advanced Mission Design: www.nasa.gov Objectives: • Minimize fuel weight • Maximize Solar system exploration Explore: Lagrange points, Halo orbits, Lissajous Orbits An Interplanetary Superhighway People: Dan Scheeres, Boulder Martin Lo, JPL Shane Ross, VTech Some Current Problems of Interest Aerocapture/Aerobraking Technologies: Some Current Problems of Interest Aerocapture/Aerobraking Technologies: Explore: Mars Global Surveyor, Mars Odyssey Entry corridor Atmospheric modeling Ablatives People: James Longuski (Purdue) Some Current Problems of Interest Formation Flying: Spacecraft Constellations Simple formation: Docking Complex formation: Maintaining cluster shape for max coverage Some Current Problems of Interest Formation Flying: Spacecraft Constellations 3-1-50 4-1-4 Flower constellations Explore: Clohessy-Wiltshire Eqns. Discrete number theory GPS constellations Flower constellations People: Daniele Mortari (TAMU) John Junkins (TAMU) Hanspeter Schaub (Boulder) Jonathan How (MIT) Some Current Problems of Interest Novel Control Methods: Coulomb Spacecraft Formation Control People: Hanspeter Schaub (Boulder) •High Earth Orbits •Control Neighboring S/C within 10-1000 m •Nearly “propellant-less control” Some Current Problems of Interest Novel Control Methods: Navigation with Solar Sails People: Dan Scheeres (Boulder) NASA/MFSC (Alabama) •Fragile spacecraft •Operates on radiation pressure Some Current Problems of Interest Space Debris Management: • Defunct spacecraft • Broken up spacecraft • New collisions www.nasa.gov View of debris in LEO • Threat to active spacecraft • Threat to astronauts www.nasa.gov Expanded view of debris to include HEO Some Current Problems of Interest Space Debris Management: www.nasa.gov Space shuttle window damage Explore: Cloud propagation Tethered Spacecraft Collision between Iridium 33 and Cosmos 2251 on Feb 10, 2009, 490 miles over Siberia People: Mrinal Kumar(UF) David Spencer (Penn State) Dan Scheeres (Boulder) NASA Orbital Debris Program Some Current Problems of Interest Uncertainty in Space: Space collisions: Space object tracking: Asteroid + Planet Debris + Spacecraft www.nature-talk.com Nonlinear Filtering Theory • Near Earth Asteroid (NEA) Program • Potentially Hazardous Asteroids (PHA’s) Asteroid 4581-Asclepius (1989-FC) Project LINEAR Project Spacewatch Project Neat Some Current Problems of Interest Uncertainty in Space: Space collisions: Asteroid + Planet Case in point: 99942 Apophis Some Current Problems of Interest Uncertainty in Space: Explore: Stochastic Systems Probability Flow Fokker-Planck equation Nonlinear Bayes’ Filtering People: Mrinal Kumar (UF) Don Yeomans, JPL Suman Chakravorty (TAMU) Dan Scheeres (Boulder) Summary • Spaceflight research has a LONG history • It has continuously spurred development in mathematics • Spaceflight research is extremely rich in mathematics • Current space research is inherently multi-disciplinary • Please see me if you want to work on one/more of the described problems!!