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Hello! My name is Linus Larsson from Sweden and the developer of the Sleipnir Velocity system.

Back in 2015 speed contests of helicopters was a big thing on sites like Helifreak. Everybody discussed how to measure speed, all companies had special “speed fuselages” to their helicopters. The best a regular person could hope for was some sort of GPS for measuring the speed, however they are quite bad at it. They differ a lot run to run, and at best you need to analyse your run at the end of the flight. I thought I can do better. I had quite a few weird ideas in my head but settled on a camera system using raspberry pies.

Work on Sleipnir Velocity started back in 2016 and a prototype of a working system took about one month to complete, there where some fixes after that but nothing major and the system was very much a prototype. In 2017 the system was put on hold, other things in life got priority. Some people around the world did build a V1 Sleipnir Velocity and actually held competitions with it, being pleased with the results. This tells me the base of the System is sound.

In 2021 one day in mid spring I saw the sad looking box of Sleipnir hardware in the basement, I decided to see if was still in order and being able to run. And it was to some extent. Some parts of it was very outdated and since it was all a prototype it wasn’t really easy to work on. I decided to fix some stuff and the project grew into what I would now say is a V2 Sleipnir Velocity system!

What are the changes from a V1 system

  • Windows 10 is now the number 1 supported platform, it was Linux in V1
  • Python upgraded to version 3 from 2.7 which is end of life
  • Base station have easier installation routines based on Python virtual environments
  • Better logging with a real logging system, no more prints
  • Simplified setup that uses a third Rasberry Pie for things such as DHCP, NTP and DNS
  • Cameras run dynamic IP so no more hardcoded, this simplifies development
  • Virtual Camera, being able to play back a flight at home just as it was at the field makes tracking development easier
  • Better Motion Tracking. The tracking is better than ever, more insects are kept out of the system.
  • Code cleanups, a lot of them Both the Python code on the base station and the C code on the camera pods.
  • SQL-Lite database instead of files, the old system saved 180 files per second on the filesystem, now everything is saved in one big database. Much easier.
  • Raspberry Pie v2.1 camera support. The 1.3 camera is getting pretty hard to get a hold on since it have been out of production for years. The v2.1 version works now and shoots at HD resolution internaly, even if scaled down it gives much better image quality that the v1.3 camera. v2.1 Needs a Raspberry Pie 4 to work due to image processing.
  • Command line arguments on the pods that actually makes sence and works as intended.
  • Average speed across both distances are calculated automatically
  • Much better installation instructions!