Sohla-1 and Sohla-2 are two 50kg small demonstration satellites in development by Japan.
The project was initiated by the SOHLA (Space Oriented Higashiosaka Leading Association) organisation in 2003. The aim of this group is to revitalize local economy by developing space technologies. In 2004 SOHLA signed a cooperation agreement with JAXA.
Sohla 1
The mission of Sohla-1 is to observe cloud building.
Sohla 2
SOHLA-2 is a 50 kg microsatellite and will be the first demonstrator of Panel ExTension SATellite (PETSAT) which was first proposed by the Nakasuka Laboratory of University of Tokyo. PETSAT consists of a combination of standardised subsystem panels that are hinged together and deploy/unfold once the spacecraft is in orbit. The PETSAT concept is configured such that mission designers can launch their own PETSAT for a significantly lower cost and shorter development time by providing the ability to select and assemble off-the-shelf panel subsystems as required. The main payload on SOHLA-2 is lightening monitoring experiment and the mission will also demonstrate end-of-life de-orbiting through the use of a low-cost on-board propulsion system. SOHLA are currently investigating launch opportunities for SOHLA-2, targeted for end of 2007 into LEO.
Glasgow based small satellite power specialist, Clyde Space, will supply the complete power system for the SOHLA-2 spacecraft. This SOHLA-2 Clyde Space power system will consist of high efficiency multi-junction solar cell panels, a lithium ion battery and power management electronics. SOHLA-2 is very unique in its design and implementation and the power system is no different. Each of the 8 spacecraft panels is equipped with its own self contained power system consisting of at least 8W of solar array, a 16Whr lithium ion battery and a power management system. The power management system consists of; active solar panel maximum power point tracker, battery charge management, voltage regulators, power distribution and protection, and a digital interface for control and monitoring purposes. Power is shared between the panels and across the spacecraft at battery level to ensure that power is available where it is needed most on the satellite throughout the duration of the mission.
Launch
Sohla-1 wíll be launched as a secondary payload to the GOSAT with the H-2A in 2008.
