Geoscan-Edelweiss (Geoscan-Edelveis, RS20S, Space-PI 15, Space π)

Designed for testing the platform and flight testing of the gas propulsion system of OKB Fakel.

16 different satellite missions within the framework of the Space-PI project with the participation of students and schoolchildren.

The first private satellite from St. Petersburg was developed by Geoscan. It is designed for flight testing of the Geoscan 3U satellite platform. The device will study the possibility of transferring nanosatellites to lower orbits using a gas propulsion system (GPU) to reduce the amount of space debris in orbital space. The GDU was manufactured specifically for CubeSat devices at the Fakel experimental design bureau. Nitrogen is used as the working fluid. 

The satellite also has a board with a GNSS receiver developed by the ELVIS Research and Production Center and a silicon wafer with the names of participants in the Send Your Name into Space campaign, which was held by Geoscan in the fall of 2021. The plate was lithographed with 22,772 names. 

This 3U mission is to test CubeSat platform: to get an experience and to educate ourselves in making and operating Cubesats. Our main goal is to create a platform for educational and popularization activities, like engineering, programming and radio amateur communication. Working with universities and middle-school students we want to give them motivation to participate in CubeSat development and operation process.

Also, the goal is to get experience as radio-amateurs and to popularize this knowledge to local amateurs. We would like to see our mission as self- training platform for our operator and local radio-amateurs to operate the satellite and ground station. This mission will serve radio amateurs around the globe in many ways. We already have our own QSL cards to give to amateurs which would like to communicate with our satellite. Firstly, it will translate CW Morse code. Secondly, telemetry information will be shared in AX25 packets to all radio amateurs and networks, and everyone will be able to receive and decode our telemetry data, what we really anticipate. Packet format and decoder for our messages will be freely available on our website: geoscan.space as well as on SatNogs database. Our website will also update with more information for amateurs to communicate with Geoscan-Edelveis during the mission. Our systems have ability to be updated from the Earth if needed. 

For more than 8 months , the Geoscan-Edelweiss spacecraft has been operating in orbit and sending photos of its home planet. However, in addition to the camera, the satellite is equipped with a gas engine from the Fakel Design Bureau , created with the support of the Innovation Promotion Fund, which is still waiting for its finest hour. The Encyclopedia has an article describing it.

The first flight test of an engine is an exciting event that requires a careful approach. The team of Geoscan's small spacecraft development department develops an experimental plan, which is adjusted depending on the results of previous experience. 

The engine consists of high pressure cylinders and a receiver - a small cylinder with low gas pressure. In fact, the receiver is a buffer volume of gas that enters here from the cylinders, and from here it is already fed directly into the engine nozzle. At the cosmodrome, high-pressure cylinders were filled with nitrogen up to 110 atmospheres, and the receiver - up to 2.5 atmospheres. There is a valve between the cylinders and the receiver, and before directing gas from the cylinders to the receiver, it must be “unblocked”. 

1. 26 April. The tests began with checking the operation of the receiver, whether gas enters the engine nozzle through the valve. During the communication session, voltage was applied to the outlet valve and the pressure in it dropped to 2.3 atmospheres. This means that the engine valve is working successfully. 
2. April 27th. To "unblock" the valve between the cylinders and the receiver, you need to turn on the heater for 20 minutes. The temperature deforms the valve and opens the gas supply path from the cylinders to the valve. During one communication session at Geoscan-Edelweiss, the operator uploaded a task to turn on the heater, he chose the time so that 20 minutes would be completed by the time of the next session. And already at the next communication session, the telemetry indicators showed that the heater worked according to plan. 
3. April 28th. We tested the transfer of gas from the cylinder to the receiver. Telemetry data showed a decrease in cylinder pressure and an increase in receiver pressure. Filling the receiver up to 9.6 atmospheres, we made another check of the engine valve opening. And this stage of testing was successful! 

The following experiments will establish what changes occur after one turn on of the receiver. Based on the results obtained, it will become clear how to construct a program for changing the orbit parameters. 

• PLATFORM - Geoscan

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