Summary
Pyxida is the custom avionics system designed for use in Project Therion, and applied in future projects. The specifications for the original system were picked during the fall 2015 semester and have been refined several times since then.
Revisions
Revision 1:
Pyxida Rev. 1 was the first iteration of the design to have a PCB. The board was designed and assembled during February 2016. It included the same sensors and microcontroller configuration of later Pyxida revisions, but was unique in that it was a BeagleBone cape that depended on the BeagleBone for power.
Revision 2:
Pyxida Rev. 2 was a minor upgrade from the original version, completed during . It retained the BeagleBone cape form factor of the original revision, but had its own 3.3v power so it could run the XBee more reliably and could be operated independently from the BeagleBone. It also featured standard headers for connections to other devices instead of the JST connectors used on Rev. 1. This version added continuity checking as well as battery voltage checking, though this feature required the use of the BeagleBone. As IREC 2016 drew closer, it became clear that the BeagleBone added too many complications to justify its place in the system, so it was removed and its software was ported to C++ and added to the firmware of Pyxida itself. This was the configuration used for the IREC 2016 competition flight.
Revision 3:
Pyxida Rev. 3 was the next major revision of the device, which was designed during the Fall 2016 semester. It dropped the cape form factor in favor of a simple rectangular PCB with mounting holes in the corners. It retains the ability to communicate with devices like the BeagleBone through an expansion port, but it will be fully functional on its own. The most commonly used connectors were changed from headers to screw terminals, while the less used features were moved to SATA connectors that can be connected to expansions boards to break them out to larger connectors. It features a new GPS from uBlox that handles flight better than old GPS, and also adds an accelerometer with higher-g ratings so it can be used to estimate motor performance. The last major in this revision was the addition of an onboard flash memory chip that configurations are loaded from and flight logs are saved to.
Revision 4:
Pyxida Rev. 4 was a minor revision completed during the 2017 Spring Semester. It includes an upgraded GPS module and support for active GPS antennas.
Firing:
4
5
6
7
Continuity:
3
2
1
0