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Naval Postgraduate School NAVAL POSTGRADUATESCHOOL Thesis/Research Opportunities

The Spacecraft Research and Design Center at the Naval The mission of the Naval Analytical and experimental investigation are performed to develop Postgraduate School consists of six state-of-the art laboratories: technologies for acquisition, tracking and pointing of flexible Postgraduate School is to Fltsatcom Laboratory, Spacecraft Attitude Dynamics and Control spacecraft with optical payloads; active vibration control, Isolation, enhance the security of the Laboratory, Smart Structures laboratory, Spacecraft Design and suppression using smart structures; robotics, United States of America Center, NPS-AFRL Optical Relay Mirror Spacecraft Laboratory, servicing, space design, and aided design tools. through graduate and and Satellite Servicing Laboratory. These laboratories are used for professional education programs Three-Axis Simulator 1 Three-Axis Simulator 2 instruction and research in space system and space • Slew maneuver torque profile to minimize settling time. focusing on the unique needs of operations curricula. The emphasis has been on providing • Active vibration isolation/suppression using smart sensors students with hands-on experience in the design, analysis, and and actuators the military officers. These programs are sustained by testing of space and systems and to provide students research and advanced studies directed towards the needs • Fast steering mirror pointing/jitter control facilities for experimental research. The emphasis in the research • Improved multi-body flexible dynamics and control models of the Navy and DoD. Our goals are to increase the combat h areas is on acquisition, tracking and pointing of flexible • Adaptive Optics Control effectiveness of the armed forces of the U.S. and its allies spacecraft with optical payloads; active vibration control, Isolation, • On- system identification of spacecraft inertia and and to contribute to fundamental scientific, engineering, and suppression using smart structures; space robotics, satellite structural natural frequencies policy, and operational advances that support the Navy, servicing, space system design, and computer aided design tools. • Ground test beds to validate spacecraft pointing DoD, and other national security establishments. Adaptive Optics Laser Jitter Control These laboratories have been used in joint projects with Naval Test-bed Test-bed Satellite Operational Center, NRL, AFRL, Columbia University, and performance. • Satellite servicing dynamics and control Boeing. (591) Space Matrix, ASTRO • Computer-aided spacecraft • Fltsatcom ground telemetry and command systems. Distinguished Professor Brij N. Agrawal Engineering Science Refresher Quarter – 460 Spacecraft Research Publications NW3230 (4-0) MA1043 (2-0) MA1118 (5-2) PH1001 (4-2)& Dr. Brij Agrawal is currently Strategy & Policy Matrix Algebra Multi Variable PH1002 (4-2) and Design Center 0 Calc Physics I & II Su Distinguished Professor in the • Watkins, R. and Agrawal, B. "The use of an LMS Filter in

(All) (Su) (All) (Su) Department of Mechanical and the Control of Optical Beam Jitter", AIAA Journal of Astronautical Engineering and Guidance, Control, and Dynamics. Vol. 30, Number 4, July- Core Curriculum Director of Spacecraft Research August 2007. AA2440 (3-2) AA2820 (3-2) MA2121 (4-0) EC2820 (3-2) and Design Center at the Naval Introduction to Structures Differential Digital Logic • Sugathevan, S. and Agrawal, B. "Optical Laser Pointing and 1 Digital Equations Circuits F Postgraduate School (NPS). He Jitter Suppression using Adaptive and Feedback Control Computation (Sp/F) (F) (All) (Sp/F) has developed research Methods," Proceedings of Beam Control Conference, SS2500 (4-0) PH2514 (4-0) MA3046 (4-1) EC2300 (3-2) Orbital Mechanics Space Matrix Analysis Controls programs in acquisition, tracking Directed Energy Professional Society, Monterey, CA, March 2 (or MA 4362) Environment W and pointing of flexible 21-24, 2006. (W) (W) (W/Su) (W/Su) spacecraft with optical payloads; • Kim, J. and Agrawal, B. "Experiments on Jerk-Limited Slew AA3815 (3-2) EO2525 (4-1) SS3525 (3-2) AA 3830 (3-2)* Spacecraft Analysis of Remote Sensing Guidance & active vibration control, Maneuvers of a Flexible Spacecraft", AIAA Guidance, 3 Dynamics Signals Control Sp for Comms AA 3811(2-2)* HEL Beam Control Isolation, and suppression using Navigation, and Control Conference and Exhibit, August 21- Space Lab Fltsatcom Laboratory smart structures; space robotics, satellite servicing, space system (Sp) (Sp) (W/Sp) (Sp) Testbed 24, 2006. AA3851 (3-2) EO3525 (4-1) AA3804 (3-0) ME 3521 (3-2)* design, and computer aided design tools. Prior to joining NPS in • Kim, J. and Agrawal, B., "Acquisition, Tracking, and Pointing Spacecraft Communications Thermal Control Mechanical 4 Propulsion Engineering of Spacecraft Vibrations 1989, he worked for twenty years for of Bifocal Relay Mirror Spacecraft," Proceedings of Beam Su Corporation (COMSAT) and International Telecommunications Control Conference, Directed Energy Professional Society, (Su) (Su) (Sp) (Su) Satellite Organization (INTELSAT) where he conducted research Monterey, CA, March 21-24, 2006. AA3818 (3-2) PH3360 (4-1) SS3035 (3-2) AA 3820 (3-2)* S/C Attitude EM Waves Microprocessors Space Systems in spacecraft attitude control, spacecraft structures, spacecraft 5 Dynamics & (or PH 2351 & (or EC2840 & Dynamics • Agrawal, B. N., Kim, J.-W., Romano, M., "Attitude Control F Control 3352) 3800) system , and spacecraft testing. He participated in the and Determination of the NPS Bifocal Mirror Testbed," 55th

(F) (F) (F) (F) development of INTELSAT IV, IV-A, V, VI, and VII, COMSTAR, International Astronautical Conference, Vancouver, AA3870 (2-2) EC3230 (3-1) SS3001 (3-2) SS0810 (0-8) and MARISAT . Professor Agrawal has written first text (Acc) Spacecraft (Acc) Space (Acc) Military Appl Thesis Experience Canada, 2004. 6 Design Tools Power of Space Tour W Flexible Spacecraft Spacecraft Design book on spacecraft design “Design of Geosynchronous • Romano, M., Agrawal, B. N., “Attitude Dynamics/Control of (W) (W) (W) (W) Simulator Laboratory Spacecraft”, has over 70 technical paper publication and has a Dual-Body Spacecraft with Variable-Speed Control Moment AA4870 (4-0) EO3535 (3-2) AA 4850 (3-2)* AA 4816 (4-0)* patent for an attitude pointing error correction system for Spacecraft Spacecraft Astrodynamic Dynamics & Gyros”, AIAA Journal of Guidance, Control, and Dynamics, 7 Design I Communications Optimization Control geosynchronous satellites. He received Ph. D. in Mechanical Sp of Structures vol. 27, No. 4, pp. 513-525, July-August 2004. Engineering in 1970 from Syracuse University and MS in (Sp) (Sp) (F) (Sp) Professor Brij N. Agrawal, Director • Agrawal, B. N., and Chen, H., "Algorithms for Active

AA4871 (2-2) Elective* Elective SS0810 (0-8) in 1968 from McMaster University, MS in Spacecraft AA 4XXX Thesis Research Vibration Isolation on Spacecraft," Journal of Smart 8 CODE ME/Ag Design II Mechanical in 1966 from Roorkee University and BS in Mechanical Su Materials and Structures, Vol 13, pp 873-8880, 2004. Department of Mechanical & Astronautical Engineering in 1964 from Banares Hindu University. He has (Su) (All) Engineering • Watkins, R. J., Agrawal, B.N., Shin, Y.S., and Chen, C., MN3331 (5-1) SS0810 (0-8) SS0810 (0-8) Elective * received NPS Outstanding Teacher Award, NPS Outstanding nd or MN3321&3322 Thesis Research Thesis Research AA XXXX “Jitter Control of Space and Airborne Laser Beams”,22 Naval Postgraduate School Researcher Award, an AIAA Space System Design Award, and 9 Systems AIAA International Communications Satellite Systems F Acquisition & Monterey, California 93943 INTELSAT Award for Inventiveness and Technological Program Mgmt Conference, Monterey, CA, 9-12 May, 2004. (All) (All) (All) Contribution. Professor Agrawal is an Associate Fellow of AIAA • Chen H., Hospodar Jr., E., and Agrawal, B. N., * Core courses for MS Astronautical Engineering Phone: (831) 656-3338 and a registered P. E. in the state of Maryland. Fax: (831) 656-2313 “Development of a Hexapod Laser –based Metrology Email: [email protected] Systems for a Finer Optical Beam Control “,AIAA http://www.aa.nps.navy.mil/~agrawal/srdc/ International Communications Satellite Systems Conference, Monterey, CA, 9-12 May, 2004. Laser Jitter Control Test-bed Optical Adaptive Optics Beam Control Spacecraft Attitude Dynamics and Relay Mirror Laboratory Control Laboratory

Laboratory High Energy Laser (HEL) Beam Control Testbed Flexible Spacecraft Simulator (FSS)

Three-Axis Simulator 1 A new joint NPS and AFRL laboratory, NPS-AFRL Optical Relay Spacecraft Laboratory, was dedicated on June 5, 2002. This laboratory is used for both instruction and research on acquisition, tracking, and pointing of flexible military spacecraft. Three-axis simulator 1 can simulate spacecraft three-axis motion as well as the optical system of a space telescope. The spacecraft The purpose of the test-bed is to Investigate control simulator has three reaction wheels and thrusters as methods to reduce optical jitter and mitigate disturbances actuators; rate gyros and sun sensors as sensors; on- to optical beams and structures. Emphases are made on board processor; batteries; and supported on a spherical Adaptive Control methods due to the expected changing air bearing. The optical system consists of laser source, a environment. FSS, as shown in the figure, simulates attitude motion in fast steering mirror, jitter sensor, and a video camera as a High Energy Laser (HEL) Beam Control Testbed is used to the pitch axis of a flexible spacecraft. It consists of a tracking sensor. Adaptive Optics Test Bed test and evaluate beam control techniques such as central rigid body representing the spacecraft central body adaptive optics, jitter control, and structure/optics and a flexible appendage representing a reflector with a Three-Axis Simulator 2 optimization required for directed energy systems. The HEL flexible support structure. This system is floated on air Testbed is housed in a class 10,000 clean room facility pads over a granite table to simulate a micro-gravity environment. The actuators are thrusters with air supplied by a compressed air bottle and a momentum wheel FLTSATCOM Laboratory Spacecraft Design Laboratory

The purpose of this test-bed is to develop improve control The three-axis simulator 2 can be divided into three techniques for adaptive optics. The current application is modules: spherical air bearing, spacecraft bus module and controlling surface of large flexible mirrors in space. The This laboratory, as shown in the figure, consists of a This laboratory houses computer–aided design tools for optical payload module. The spacecraft bus has three test bed has two adaptive optics systems (two deformable qualification model of the Navy communications satellite, spacecraft design and a spacecraft design library. It has variable speed control moment gyros (CMGs), Northrop mirrors and two wave front sensors). One system corrects FLTSATCOM, the associated ground support equipment GENSAT, a general-purpose software application for the Grumman Litton LN-200 IMU consisting of three fiber optics the surface of flexible mirror and the other system correct for testing the satellite, and the FLTSATCOM Attitude satellite design, and Center (CDC) rate gyroscopes, sun sensors, magnetometers, the aberration in imaging object beam. The test bed also Control Simulator, which provides a graphical display of the software from Aerospace. In addition, it has several subsystem inclinometer, fine sensor, batteries, power switching and has fast steering mirror for correcting jitter. The test bed spacecraft’s attitude and rotational motion in response to design software, such as STK, NASTRAN, IDEAS, control electronics, and automatic balancing system. The has two beams: reference beam and object beam. The commands similar to the commands required for flight Matlab/Simulink. Using these unique design tools, students optical payload consists of receive telescope and can do collaborative spacecraft design reference beam is used by the sensors and actuators to model FLTSATCOM spacecraft. associated optical equipment on the upper platform and correct flexible mirror surface and beam jitter introduced in transmit telescope and associated optical equipment on the the spacecraft. lower platform.