Tohoku University

Tohoku University Research News of Engineering (Tune) is a biannual publication of School of Engineering (SoE), Tohoku University, Sendai, Japan. Each Tune volume provides the scientific community with the latest research results of SoE on a selected topic.

Research Highlight

RISING-2 Seen Meeting Future Challenges

Text by S". Tex" POMEROY / Photographs by Masayoshi HARABUCHI

As our readers may know, artificial satellites are being developed by many universities around the world today after the first 1kg satellite "cubesat" was launched in 2003. With this background, we are the world's leading research & development laboratory within the academic micro- and nano-satellites community. Our laboratory has much experience in satellite development and operation, now totaling at 5 satellites. The first micro-satellite SPRITE-SAT (RISING), launched in 2009, is currently in space, and our first 2.6-kg cubesat RAIKO was released into space from International Space Station in 2012.

RISING-2 Seen Meeting Future Challenges

Recently our second micro-satellite RISING-2 entered into orbit at 628km altitude by the Japanese H-IIA rocket, on May 24, 2014. A month later, color images of the Earth surface were observed at about 5m spatial resolution by utilizing the High Precision Telescope (HPT). This spatial resolution holds the world record in the under-50kg category for micro-satellites. HPT can observe multi-spectrum images selected from 400-band wavelength using a liquid crystal tunable filter (LCTF), this being a world-first trial in space. To help deal with climate phenomena, such as cumulonimbus clouds and isolated heavy rains, a wide-field bolometer array with a mid-infrared imaging sensor is also installed. The success of these experiments will offer a new Earth observation method that equals those of traditional large or mid-sized satellites. This is a gigantic first step for micro-satellites to become part of a socially beneficial infrastructure in the near future. Now, we are developing the upcoming next-generation micro-satellite RISESAT with five international science missions.

Upon development of RISING-2 commencing from 2009, I controlled the budget of about US$3.8 million, the schedule and the team including seven graduate students, as project manager.

The detailed designs handled mainly by students followed, such as structure design as well as the electrical hardware and software design related to attitude control and determination. The efficient processes of design, fabrication and testing were made possible; thus, the flight model was completed in just 18 months.

Keen interest from around the world is being focused upon our frontline technology and seasoned proficiency regarding the development of artificial satellites. In tandem with our development work, we are implementing the concept of high-frequency Earth observations at multi-points based on the use of 48 cluster satellites with multi-spectrum HPTs. For the students and researchers who want  to join the research team, their time with us will offer an invaluable experience.

N. Sugimura, K. Fukuda, Y. Tomioka, M. Fukuyama, Y. Sakamoto, T. Kuwahara, T. Fukuhara, K. Yoshida, Y. Takahashi, "Ground Test of Attitude Control System for Micro Satellite RISING-2," IEEE/SICE International Symposium on System Integration (SII 2012), pp.301-306.