The Results of Small Satellite Technology Transfer from JAXA

The satellite named MAIDO-1 finished its 9-month life, on October 15, 2009. The MAIDO-1 was developed by Space Oriented Higashiosaka Leading Association (SOHLA). Japan Aerospace Exploration Agency(JAXA) transferred their space technology to small and medium-sized enterprises (SMEs) and local universities in the Kansai area. The purpose of this activity is to contribute to socio-economic development by returning JAXA research and development results to society. The MAIDO-1 is one of its program achievements. This paper shall explain the matter of the technology transfer, the SOHLA-1 satellite system, on-orbit experimental results, and the results of technology transfers

Small Demonstration Satellite-4 (SDS-4): Development, Flight Results, and Lessons Learned in JAXA’s Microsatellite Project

The Small Demonstration Satellite 4 (SDS-4) is the first zero momentum three-axis controlled 50kg class satellite from JAXA. It was launched on May 17, 2012 on H-IIA Launch Vehicle, and is now operating successfully. SDS-4 has four main demonstration missions: (1) Space-based automatic identification system experiment for tracking ships, (2) Flat-plate heat pipe on-orbit experiment, (3) Quartz crystal Microbalance for contamination environment monitoring, and (4) In-flight experiment of space materials using THERME, which is developed in the JAXA-CNES joint research program. The satellite has two deployable solar panels to the left and to the right, and two deployable AIS antennas in the front and in the back. In addition to the technology demonstration missions, SDS-4 has another important goal, namely to establish a 50 kg-class highly functional and precise three-axis controlled standard bus for future advanced missions. After a year of on-orbit experiments and evaluations, all missions are now deemed successful and excellent flight data has been obtained. We encountered several serious problems during operations. We investigated the reasons for those misbehaviors in a multi-step process using a methodical FTA approach, and managed finally to resolve all of the problems. This paper concludes with the lessons learned all of which contributed to the overall success of the SDS-4 project

Additive Electron Pathway and Nonadditive Molecular Conductance by Using a Multipodal Bridging Compound

We designed and synthesized a new quadrivial anchoring unit <b>4-TEB</b>, to construct a stable single-molecule junction with gold electrodes, which should have equivalent conducting electron pathways between two electrodes. The conductances of single-molecule junctions comprising <b>4-TEB</b> and its bidirectional counterpart <b>2-TEB</b> were determined to be 2.7 × 10^–4<i>G</i>₀ (2<i>e</i>²/<i>h</i>) and 5.0 × 10^–5<i>G</i>₀, respectively, by using scanning tunneling microscope break junction (STM-BJ) techniques. The single <b>4-TEB</b> molecule junction had higher stability and conductivity compared to those of the single <b>2-TEB</b> molecule junction. Although the number of electron pathways from/to the electrode to/from the molecule was additive using the equivalent multianchoring, the conductance of the single-molecule junction was not additive. From first-principles electronic transport calculations, the mechanism for the new quadrivial <b>4-TEB</b> single-molecule junction involved an overlap resonance effect to the HOMO conducting orbital, giving rise to tunneling. Using fixed nanogap electrodes, we constructed stable molecular junctions of <b>4-TEB</b> and observed symmetric peaks in the derivative of the conductance–voltage (<i>G–V</i>) curves, which were assigned to electron transport through the HOMO on the basis of theoretical calculations