Non Advocate Review October 3 2002 Space System Product Development Class Department of Aeronautics Astronautics MIT Electro Magnetic Formation Flight Of Rotating Clustered Entities GG Welcome to the Non Advocate Review for project EMFFORCE Electro Magnetic Formation Flight of Rotating Clustered Entities 1 Introduction Amilio Aviles GG NAME will be giving an introduction for the presentation She will address the mission statement as well as background and motivation for the project provide a brief requirements summary and then give an overview for the rest of the presentation 2 EMFFORCE Space System Product Development Class Actuation Jesus Bolivar William Fournier Lindsey Wolf Melanie Woo Formation Flight Amilio Aviles Andr Bosch Oscar Murillo Leah Soffer Electronics Stephanie Slowik Erik Stockham Maggie Sullivan Jennifer Underwood Structure Power Geeta Gupta Amy Schonsheck Timothy Sutherland CDIO3 Class Project Systems Oscar Murillo Stephanie Slowik Melanie Woo 3 GG After the Trade Analysis and Requirements Review in March 2002 the Space System Product Development Class split itself into four groups before embarking on the design process These groups as listed above were further split into smaller teams responsible for the following actuation electromagnet reaction wheel formation flight metrology control electronics avionics communications structure power structure and power design The three member systems group is comprised of one member from three of the four groups at any given time The members of this group are on a seven and a half week rotation The governing team therefore always has two experienced members All groups also have a liaison to the rest of the class and sub system groups This sub system systems group structure will remain for the rest of the EMFFORCE project 3 EMFFORCE NAR Purpose Introduction Background Requirements Summary Mission Approach Subsystems Integration Budgets Conclusion Review progress to date To review the methodology for completing the design and operation of the EMFFORCE test bed To gain insightful feedback from those more experienced CDIO3 Class Project 4 GG The purpose of the NAR presentation is 4 EMFFORCE Advantages of Formation Flight Introduction Background Requirements Summary Mission Approach Subsystems Integration Budgets Conclusion Large baselines to improve angular resolution Smaller vehicles z Ease of packaging launch and deployment Redundancy z Mission does not fail if one satellite fails Reconfigurable z z z Replace individual space craft Can integrate new technology during mission Staged deployment CDIO3 Class Project 5 GG Advantages of formation flight include higher resolution with smaller vehicles To achieve similar resolution would be much more costly with one large vehicle rather than with more than one formation flight vehicles The smaller vehicles also prove easier to pack launch and deploy Not only do formation flight satellites allow for failure continuing the mission with few satellites when one breaks down these systems also allow for new technologies to be integrated in to occurring missions 5 EMFFORCE Challenges of Formation Flight Introduction Background Requirements Summary Mission Approach Command and Control Subsystems Integration Budgets Conclusion Propellant Drawbacks z z z z z Control multiple vehicles position Control position relative to other vehicles Fuel limits lifetime Exhaust particulates contaminate imaging instruments Exhaust creates haze which limits imaging CDIO3 Class Project 6 GG In current formation flight done with thrusters the propulsion system actuates each vehicle with inertial degrees of freedom however for formation flying satellites in order to remain in formation the satellites should also be able to actuate their relative position motion to other satellites There are also many drawbacks to the use of propellants Not only does the amount of fuel limit the lifetime of the mission but exhaust particles can contaminate and damage imaging equipment contact contamination as well as create a haze of pollution that the telescope must look through radiative contamination 6 EMFFORCE Definition of Electromagnetic Control Introduction Background Requirements Summary Mission Approach Subsystems Integration Budgets Conclusion Implement electromagnetic dipoles to create forces and torques between the vehicles Dipoles can be controlled by varying the amount of current through the electromagnet coil z z Can provide steady forces and torques for maneuverability Can provide disturbance rejection for more precise control CDIO3 Class Project 7 GG Electromagnets will create dipoles that will provide the thrusting forces and torques between vehicles The strength of dipoles can be controlled by varying the amount of current through the electromagnet coil Control of the dipole strength as well as direction rotation of magnet can provide large forces for maneuvering as well as small disturbance rejection for more precise control 7 EMFFORCE Advantages of EMFF Introduction Background Requirements Summary Mission Approach Subsystems Integration Budgets Conclusion No thrusters Fewer consumables Longer life z Zero pollution No contact contamination to imaging equipment z No pollution haze No radiative contamination to imaging equipment z Control of relative position CDIO3 Class Project 8 GG In order to overcome the challenges of formation flight as described before the MIT Space Systems Laboratory SSL has begun the investigation of elector magnetic formation flight Thrusters and their propellants impose many of the undesirable aspects of current formation flight EMFF because it does not use propellants will not have a lifetime limited by the amount of fuel on board nor will contact contamination or radiative contamination be a problem Since formation flight requires precise relative control EMFF leads to better control because EMFF controls the relative position instead of the absolute position 8 EMFFORCE Challenges of EMFF Introduction Background Requirements Summary Mission Approach Subsystems Integration Budgets Conclusion Control Problem z z Unstable not unique to EMFF Coupled control z Each vehicles motion affects all other vehicles Electromagnet Drawbacks z z Ferromagnetic material is heavy Electromagnetic force is weak z Force in the far field drops of as the 4th power of separation distance Electromagnetic interference with other electronic subsystems CDIO3 Class Project 9 GG One of the current challenges