In our previous post we introduced the heart of our avionics system, the flight computer board, and mentioned that it uses two GPS daughterboards which are also in-house designed. These are crucial for providing us with position and velocity. During flight, they constantly send data to the flight computer, which is then processed and fed into the state estimation algorithm. During the descent phase, this data serves as the basis for our guided recovery system, which steers the parachute such that our rocket NICOLLIER lands in a predefined area.
The board itself houses a ZED-F9P GPS module that has all its communication and control signals routed to a board-to-board connector, through which they become accessible for our flight computer. The antenna line feeds directly to a standard u.FL style antenna connector on the daughterboard, complete with a connector retention mechanism. Power is received over the board-to-board connector or the USB connector with on-board ideal diode based power switchover. This makes the GPS breakout board even more versatile, as it can also be used standalone through USB without a carrier board, but it is still possible to have the USB connected while the carrier is powering the daughterboard. There is a possibility to connect a supercapacitor or backup backup over the board-to-board connector to facilitate warm start, and get a quicker GPS fix.
