The Binar Space Program\u27s (BSP) second mission consists of three 1U CubeSats scheduled for launch in August of 2024. Following the partial success of the BSP\u27s first mission, Binar-1, many technological improvements have been made to the Binar 1U platform. These improvements enable Binar 2, 3, and 4 to carry 0.5U of payload, which is being used by the Australian Commonwealth Scientific and Industry Research Organization (CSIRO) to test two new radiation shielding materials developed in Australia. In addition to the primary payload, each CubeSat will fly three different communication systems, new deployable solar arrays and carry operating software that will allow the amateur radio community to play capture the satellite with any of the three CubeSats.
The use of three almost identical satellites allows for comparing the performance of the two radiation shielding materials against a control. One CubeSat will be flying the payload with regular aluminium shielding, and the remaining two will have different aluminium metal matrix composites made using a friction-stir additive manufacturing method. The materials are intended to be used as a lightweight alternative to standard space-grade aluminium with a higher resistance to the space radiation environment. The mission is the first test of the materials in orbit, demonstrating the suitability of the manufacturing method for space flight.
The three communication systems on board include an industry-led S-band transmitter designed and built in Western Australia, a new UHF transceiver developed in-house, and an Iridium 9603 modem for reduced latency communications and higher platform reliability. The novel deployable solar arrays being flown on Binar-2, 3, and 4 were designed using a rigid-flex PCB as the structure and Shape Memory Alloy (SMA) strips as deployment actuators. The panels greatly increase the power available from the Binar CubeSat platform, enabling the increased payload space to be used more effectively for space research and technology development. Part of this additional available power is being used for the capture the satellite game that will be hosted on the three Binar CubeSats. More frequent transmissions will allow radio amateurs to locate the CubeSats more easily and program their callsign into the CubeSat beacon, capturing the satellite.
Additionally, this mission aims to demonstrate several capabilities crucial to the success of future missions. Attitude determination and control using the onboard magnetometers and megnetorquers has been developed to aid directional communication and is required for sensing, imaging, and propulsion on larger missions. Due to the suspected thermal management issues on Binar-1, thermal modelling is considered a key capability for the success of future missions. Predictions derived from a simplified thermal model will be verified on orbit.
The complete development of Binar-2, 3, and 4 was scheduled to take two years following the launch of Binar-1. However, due to chip shortages and knowledge loss due to the departure of engineers and graduating students, the launch was moved to 2024. This additional time was used to perform more robust testing and develop better documentation, enabling better management of the challenges experienced on future launches. Many more lessons have been learnt through the mission lifecycle which the Binar Space Program now plans to take forward into the development of a 12U CubeSat platform
