James Dougherty, co-founder and owner of Real Flight Systems, was looking at how to increase the performance of his high-altitude rockets…
James’s goal was to build a ‘plug and run’ video system within a rocket, allowing high-definition video to be captured throughout the entirety of the flight. He also required a fully functioning Linux system that would allow for the recording of in-flight telemetry.
You can totally see the direction he’s headed in, right?
This requirement called for long battery life, high storage to accommodate up to 1080p video, and a lightweight processor, allowing the rocket to be robust and reliable while in flight.
Unsurprisingly, James decided to use the Raspberry Pi for his build, settling for the model B.
Before starting the build, James removed the HDMI port, composite video output, USB post, audio jack, and Microchip LAN9512. Not only did this lessen the weight of the Pi, but these modifications also lowered the power needed to run the setup, thus decreasing the size of battery needed. This shrunken unit, completed with the addition of a Pi camera, meant the Pi could run for 8-10 hours with the recording quality lowered to 720p60 and no audio captured.
Sadly, the first launch had its issues: the rocket suffered a system failure that resulted in the destruction of the micro SD during the Pegasus flight at BALLS 23, an experimental rocket launch event in the Blackrock desert, USA.
Rockets Magazine managed to record the launch which shows the highlights mid-flight.
James Dougherty Pegasus flight at Balls 23
However, the next launch was far more successful, with close friend Jimmy Franco launching Rocket-Pi within a Dominator 4 to record the following footage.
(This clip comes with a motion sickness warning!)
Jimmy Franco flies Dominator-4 at TCC’s February Launch (02/21/15 on an L1355.
So what was next?
Aside from a few issues with Windows when trying to upload the footage post-flight, the main gripe was the lack of audio.
Investing in a new Raspberry Pi, making sure to keep more of the original components intact, James also updated the board with a USB microphone, added a USB flash drive to eliminate the Windows issues, and replaced the SD card with a lower storage option, as the footage was now stored in the flash drive.
Launch and recovery of 1/3 Scale Nike Smoke at Tripoli Central Californias June 20th Launch. The vehicle flight-ready weighed 30 lbs, L3150 produces 800lbs initial thrust so we had about 26.6 G’s (burnt time 1.1440 seconds). Max speed: Mach 1.2; Max Altitude, 8,837′ AGL (GPS).
In the meantime, as James has continued to work on the Rocket-Pi, updating the hardware and code, he’s managed to put the Pi through some vigorous testing. During the most recent flight in Blackrock, the Pi reached 48K MSL (48000 feet above sea level… wow), at a speed of up to Mach 1.8 (1381 miles per hour… double wow).
Moving on from the build, James aims to upgrade various features. One of the most exciting upgrades looks to be the migration of Rocket-Pi to the Pi Zero, the smaller size allowing for multiple units in one rocket… creating 360-degree coverage of the flight (yes please!).
More of the build information, coding, and flight documentation can be found at the RFS website.