Martlet IV Avionics
CUSF’s Most Advanced Avionics Yet.
Project Strix is a culmination of over a decade of iteration on flight computer design for our Martlet series of launch vehicles. Powered by an Arm Cortex-M4, Strix is able to simultaneously provide accurate altimetry and control of flight systems, resiliently store flight logs, and support telemetry and telecommanding from a ground station over an ISM band radio link.
Bespoke. Compact. Powerful.
By designing around Martlet IV’s airframe, we have been able to tune Strix’s performance to the max. Our custom single-board flight computer is designed around the rocket’s specific capabilities.
With antennas conformed to the contours of the airframe, dual firing channels designed for the Falcon recovery system, and 6 sensor channels designed to log PULSAR engine data at a high rate, Strix is able to control flight systems to a minute level, with minimal overhead.
Many Happy Returns.
Two separate firing channels power the Falcon recovery system, which will bring Martlet IV back to the surface in one piece. Each firing channel can provide either 1A or 3A of current to a metron actuator, which control the drogue and main parachutes.
Firing safety is built in to Strix on a hardware level. The firing channels can only be fired upon activating both a hardware firing key and a software-controlled control voltage. Should the actuators fail to fire at apogee, they can be remotely commanded via Strix’s telecommand system to ensure chute deployment during descent.
Home, Safe and Sound.
Strix’s entirely custom-built ‘black box’ is designed to withstand impact with the ground in the event of a recovery system failure. Containing both onboard flash storage and a microSD card for redundancy, the system is able to withstand the equivalent impact of ten grenades.
To make the system as compact and as possible while maintaining reliability, the box contains only storage peripherals, which are accessed through SPI over a standard RJ45 cable. Once retrieved from the rocket, the SD card can be removed and connected directly to a computer, or the flash can be addressed directly by plugging into the ground station.
Radio, Without the Amateur.
Strix’s radio system provides two-way communication with our ground station throughout fuelling, launch, and landing. Powered by a secure ISM-band link with low-density parity checking to ensure data integrity, our radio link transmits flight data back to base and allows us to send commands to each subsystem.
An onboard GPS receiver, when paired with our telemetry system, will aid in recovery efforts by broadcasting the rocket’s location once landed. Powerful system integration ensures this low-power, entirely custom goelocation system can run unaided for long durations for seamless recovery.