From Camp 2011 Public Wiki

System Description

We intend to build 6 CubeSats with a lifespan in space of 6 to 8 months. The complete system will consists of these satellites and a ground station for communicating with these CubeSats. In order to build these CubeSats we need to define and divide the mission into subsystems, and are therefore looking for more teamplayers who would like to take control of the following subsystems:

       Spacecraft (s/c) structure

The requirements for the mini satellites are based on the CubeSat concept. The weight of each CubeSat must not exceed 1 kg, and the dimensions has to be 10 x 10 x 10 cm. To achieve this, light materials are used to develop and build the structure of the s/c (spacecraft). Its design will be based on a frame of aluminum with sides made of carbon fibers. Because of the harsh environment high requirements need to be set regarding the structure of the s/c and its integrity, to withstand a range of temperatures from +80 to -30°C, as well as shocks and vibrations, radiation, the vacuum in space etc. The team in charge for the s/c structure will also be rsponsible of the limited weight and finances of components, which other subsystems are confined to. The s/c structure will be developed by the teams which we will be discussed during the workshop as well as further steps.(TBD)

       Power supply (PSU)

The power supply unit (PSU) relies on four 3.7 V Li-Ion batteries and/or several triple-junction solar cells/panels, which will be mounted on the surface of 5 of the 6 sides of the CubeSat. The PSU is being used to gather electric power and provides other subsystems with a nominal voltage of 5 volt as well as for monitoring the performance of the different subsystems regarding their power consumption. The solar panels will also be used as backup sun sensors for particular subsystems (TBD).

       On-Board Computer (OBC)

The OBC functions as an interface for all other subsystems and is designed as a platform for the Command and Data Handling (CDHS). We are planning to use the OBC of the type C161PI from SIEMENS. It has a 16-bit CPU and 24 Megabytes Total Linear Address Space. The OBC will use two types of memory. A ROM module for stack operations and buffers and a RAM module for system software, housekeeping and payload data. The communication between the subsystems and the on-board computer will run over a bus, which will connect between the Power Supply Unit, the Attitude Determination and Control, The Camera and the Communication Unit. The OBC has been the responsibility of (TBD). For further reading we suggest DESIGNING ON BOARD COMPUTER AND PAYLOAD FOR THE AAU CUBESAT

       Payload camera

       Communication unit

       Attitude determination and control system

       Ground station

       Launch capabilities