qbkit edu emulates the mechanical and electrical interfaces of a nanosatellite mission: power and data interfaces, flexible mechanical interfaces and an Open Source computing platform running Linux OS.
The main components of the qbkit edu are:
- qbkit edu electronics
- Beaglebone Open Source computer.
- qbkit power and data interfaces shield for Beaglebone.
- 3d printed structure
To keep the dimensions of the qbkit board as small as possible our electronics engineers designed the board in a way that the blue part in the red circle is be laid flat during manufacturing and easily accessible for the user. It is not damaged/bent.
qbkit edu electronics
qbkit edu electronics contain:
- Converter 1 and converter 2 step down converters with up to 3A current rating. These converters come with voltage already set and shall not be changed. Factory configuration is the following one:
- Converter 1: 3.3V
- Converter 2: 5V
- Converter 3: step up converter with manually configurable voltage. You can adjust manually the voltage of this converter. Range: from Vin (12V with adaptor supplied) to 28V. Current rating is limited by the qbkit edu power supply (12V at 2A max).
Each power bus contains a current sensor.
qbkit edu electronics contains another step down converter currently not being used.
qbkit edu electronics contain the following data buses:
- 2x GPIO
qbkit edu PL interface pinout
The following table shows the pin out of the payload connector on the qbkit edu electronics.
|Header||Pin number||Pin name||Comment|
|Payload_power_P||2||O3.3||Converter 1 V+ 3V3|
|Payload_power_P||4||O5||Converter 2 V+ 5V|
|Payload_power_P||6||OH||Converter 3 V+ high power|
|Payload_data_P||1||CAN_H||CAN bus high line|
|Payload_data_P||2||CAN_L||CAN bus low line|
|Payload_data_P||3||I2C_SCL||I2C bus clock|
|Payload_data_P||4||I2C_SDA||I2C bus data|
|Payload_data_P||5||SPI_CS0||SPI chip select|
|Payload_data_P||7||SPI_D0||SPI master MISO|
|Payload_data_P||8||SPI_D1||SPI master MOSI|
|Payload_data_P||11||GPIO1_12||General purpose input/output|
|Payload_data_P||12||GPIO1_13||General purpose input/output|
qbkit 3D printed structure
This section explains the 3d printed structure that acts as baseline for your creations. The parts has been designed to be printed in ABS or PLA and takes into account the tolerances of 3d printing non-professional machines. Test prints might be needed and CAD models adjusted depending on your printer, settings and materials. The 3d printed structure is composed of two main parts:
- qbkit edu electronics box
- qbkit edu structure
Most of qbkit edu structure parts join together without fasteners by using a pin to hole approach. The flexibility of the 3d printed material allows the assembly of the structure.
The CAD step files can be visualised and downloaded here.
The .stl files to 3D print the parts together with indicative images can be downloaded here.
Please notice that when 3D printing the files, you may avoid warped prints by adding a raft platform adhesion type.
A video showing the assembly of the parts can be seen here.
qbkit edu electronics box
qbkit electronics are fixed inside a 3D printed box consisting of two parts. This electronics box protects the qbkit edu electronics and allows them to be integrated into the qbkit edu structure.
The lower part of the box contains holes were M2.5 nuts can be inserted. The upper part of the box contains countersunk through holes for M2.5 fasteners with a length of 20mm.
qbkit edu structure
qbkit edu structure is formed of three main elements:
- Vertical elements: act as the main link for the elements inside the structure
- Horizontal elements: link vertical elements. They also contain a feature that allows to insert an M2.5 nut in it to provide a mechanical interface to closure panels or exterior elements.
- Closure panels / exterior elements: They mechanically interface with the horizontal elements with M2.5 fasteners.