Discipline: Technology and Engineering
Subcategory: Electrical Engineering
Session: 3
Tamunoenefaa Harry - Tuskegee University
Co-Author(s): Austin Harris, Tuskegee University,Tuskegee ; AL, Julian Thompson, Tuskegee University,Tuskegee , AL
CubeSats [1,2] sensors/instruments and actuators, which use the geo-magnetic field, are packaged in a small volume due to the size, weight, and power constraints imposed by the CubeSat Design Specification [3], These magnetic sensors/instruments, which are required to measure ambient fields, are susceptible to magnetic contamination by the CubeSat actuators (permanent magnets, magnet torquer bars) which can adversely impact their performance. The intent of our research is to experimentally determine the magnetic fields generated by the actuators, construct three dimensional (3D) magnetic maps of CubeSat attitude actuator representations, compensate the ambient field measurements and facilitate the development of magnetically clean CubeSats.
A tri-axial Helmholtz Coil Cage (or HCC), with four precision magnetometers, is set up in the Department of Aerospace Science Engineering at Tuskegee University to facilitate the experimental determination of the magnetic field generated by the magnetic actuators of a CubeSat. A series of experiments are planned and executed in the HCC to measure the magnetic fields generated by – (i) two simple bar magnets and (ii) magnet torquer bar (MTB). A DC power supply is used to actuate the MTBs. The systems under test (SUT) are securely placed on the rotating platform of the HCC, which is configured to negate the magnetic field generated by the Earth. After placing the SUTs on the rotating platform, a LabView based control software is used to set the table in motion and extract measurements from the four precision magnetometers. One complete rotation of the actuated SUTs generates 4 rings of magnetic field measurements magnitude and direction of the SUTs. By translating the four magnetometers along the height of the SUTs, multiple sets of 4 rings are generated, which are then extrapolated to form cylinders of magnetic field measurements. The cylinders thus generated form the basis for magnetic maps, which are constructed in MATLAB to determine the magnetic field distribution of the SUTs. The concept when applied to an entire CubeSat results in the generation of the magnetic map of the CubeSat under test. These maps are useful in determining the location for magnetically sensitive systems in a CubeSat. These 3-D vector maps allow an engineer/scientist to strategically design CubeSats to be magnetically clean.
References:
1. Heidt, H., Puig-Suari, J., Moore, A., Nakasuka, S. and Twiggs, R., 2000. CubeSat: A new generation of picosatellite for education and industry low-cost space experimentation.
2. Chin, A., Coelho, R., Nugent, R., Munakata, R. and Puig-Suari, J., 2008, September. CubeSat: The Pico-satellite Standard for Research and Education. In AIAA Space 2008 Conference & Exposition
3. Mehrparvar, A., Pignatelli, D., Carnahan, J., Munakat, R., Lan, W., Toorian, A., Hutputanasin, A. and Lee, S., 2014. Cubesat design specification rev. 13. The CubeSat Program, Cal Poly San Luis Obispo
Funder Acknowledgement(s): Acknowledgements: We would like to express our sincere appreciation of Ms. Karen Yamrick, a former student at Tuskegee University (TU), for setting the standard for undergraduate research at TU. We thank Mr. Bruce Heath, Laboratory Manager for Aerospace Science Engineering at TU for helping us with experiments. We also express our deep gratitude towards U.S. Department of Defense Air Force Office of Scientific Research and National Science Foundation for providing funding for the research.
Faculty Advisor: Sharanabasaweshwara Asundi, sasundi@tuskegee.edu
Role: I collected testing samples of the magnetic field generated by the magnet torquer bars and used that data to construct a three dimensional magnetic vector map using MATLAB.