Space structures encounter various special environments in space. One of these environments is severe thermal condition. Difference of temperature of space structures during day-time and night-time is about 200 kelvin. These severe thermal conditions cause thermal deformation of the structures. In fact, we observed the signal level of radio wave from the LDR (Large Deployable Reflector) of the ETS-VIII (Engineering Test Satellite -VIII) changing during the Earth eclipse. This phenomenon may be caused by thermal deformation of the LDR. This thermal deformation is a key issue to maintain the accuracy of communication beams reflected by the space antenna. Analysis of thermal deformation of the LDR is carried out, and a new suppression scheme for thermal deformation is proposed in this paper.

Temperature of the LDR during Earth eclipse 　　　　　　　　　　　　　　Signal level of radio wave from the LDR during Earth eclipse

Movement of communication beam during Earth eclipse 　　　　　Movement of communication beam reflected by the LDR

Related papers (Journals):

D. Isobe and M. Morishita: Debris Impact Analysis of Large-Scale Space Structures by Using ASI-FEM, Transactions of the Japan Society of Mechanical Engineers, Series A, Vol.64, No.627, (1998), pp.2726-2733, in Japanese. abstract

M. Usui, K. Wakita, K. Kondo, L. T. T. Thanh, Y. Matsui and D. Isobe: Suppression of Thermal Deformation of the Large Deployable Reflector, Transactions of the Japan Society of Mechanical Engineers, Series C, Vol. 77, No. 777, (2011), pp.2107-2119, in Japanese. abstract

K. Shoji, M. Usui and D. Isobe: Numerical investigations on thermal deformation of large deployable reflector in space during earth eclipse (1st report, fundamental investigations to suppress thermal deformation and thermal deformation analysis), Transactions of the Japan Society of Mechanical Engineers, Vol. 81, No. 830, (2015), p. 15-00351, , in Japanese, (http://doi.org/10.1299/transjsme.15-00351). abstract

K. Shoji, M. Usui and D. Isobe: Numerical investigations on thermal deformation of large deployable reflector in space during earth eclipse (2nd report, investigations to suppress thermal deformation by internal force control), Transactions of the Japan Society of Mechanical Engineers, Vol. 82, No. 836, (2016), p. 15-00637, in Japanese, (http://doi.org/10.1299/transjsme.15-00637) abstract

K. Shoji, D. Isobe and M. Usui: Numerical Investigations to Suppress Thermal Deformation of the Large Deployable Reflector during Earth Eclipse in Space, The Aeronautical Journal, Vol. 121, No. 1241, (2017), pp. 970-982, (https://doi.org/10.1017/aer.2017.33). abstract

D. Isobe and M. Morishita: Impact Analysis of Space Structure due to Collision with Hypervelocity Space Debris by Using ASI-FEM, Proceedings of the International Conference on Computational Engineering Science (ICCES'98) -Modeling and Simulation Based Engineering-, Vol.2, (1998), pp.1114-1119, Atlanta, USA. abstract

K. Shoji, M. Usui and D. Isobe: Thermal Distortion Analysis of the Large Deployable Reflector Using FEM, USB Proceedings of APCOM & ISCM2013, (2013), Singapore. abstract

K. Shoji, M. Usui and D. Isobe: A Numerical Investigation to Suppress Thermal Distortion of Large Deployable Reflector on ETS-VIII, Extended Abstracts of the 1st International Conference on Computational Engineering and Science for Safety and Environmental Problems (COMPSAFE2014), (2014), pp. 428-430, Sendai, Japan. abstract

K. Shoji , D. Isobe and M. Usui: Thermal Deformation Analysis of Large Deployable Antenna Reflector in Space, CD-ROM Proceedings of the Conference on Computational Engineering and Science, Vol.19, (2014), in Japanese. abstract

K. Shoji, M. Usui and D. Isobe: A Numerical Investigation to Suppress Distortions of Large Deployable Reflector in Space During Earth Eclipse, Proceedings of the 11th World Congress on Computational Mechanics (WCCM XI), (2014), Barcelona, Spain. abstract

K. Shoji , D. Isobe and M. Usui: A Study on Thermal Deformation Compensation of Large Deployable Antenna Reflector in Space, CD-ROM Proceedings of the Conference on Computational Engineering and Science, Vol.20, (2015), in Japanese. abstract

K. Shoji , D. Isobe and M. Usui: Compensation Analysis of Thermal Deformation Occurred in Space-Use Large Deployable Reflector Using FEM, Proceedings of the 28th JSME Computational Mechanics Conference, No.15-19, (2015), in Japanese. abstract

K. Shoji, M. Usui and D. Isobe: Numerical Investigations to Suppress Thermal Deformation of the Large Deployable Reflector during Earth Eclipse in Space, Proceedings of the 7th Asia-Pacific International Symposium on Aerospace Technology (APISAT2015), (2015), Cairns, Australia. abstract

K.Shoji, M. Usui and D. Isobe: Modeling of a Large Space Structure for Thermal Deformation Compensation Analysis, European Congress on Computational Methods in Applied Sciences and Engineering 2016 (ECCOMAS2016), (2016), Crete, Greece. abstract

K.Shoji, M. Usui and D. Isobe: A Study on Thermal Deformation Compensation of Large Space Structure, Proceedings of the 12th World Congress on Computational Mechanics (WCCM XII), (2016), Seoul, Korea. abstract

K. Shoji , D. Isobe and M. Usui: A Study on the Designing of Module-Type Deployable Antenna for Highly EfficientThermal Deformation Compensation, Proceedings of the 29th JSME Computational Mechanics Conference, No.16-4, (2016), in Japanese. abstract

K. Shoji , D. Isobe and M. Usui: A Basic Study on a Design for Space-Use Large Deployable Reflector Focused on Thermal Deformation Compensation, CD-ROM Proceedings of the Conference on Computational Engineering and Science, Vol.22, (2017), in Japanese.abstract

K. Shoji , D. Isobe and M. Usui: Effects on Thermal Deformation Compensation for Large Space Structure by Combining Several Suppression Means, CD-ROM Proceedings of the Conference on Computational Engineering and Science, Vol.23, (2018), in Japanese.abstract

K.Shoji, M. Usui and D. Isobe: High-precision Control Method for Large Space Structure Subject to Thermal Deformation, Proceedings of the 13th World Congress on Computational Mechanics (WCCM XIII), (2018), New York, USA. abstract

Active Control of Deformation and Vibration of Large-Scale Space Structures