anybody working on a trajectory plugin?
mhaberler | Premium last edited by mhaberler
I just found an interesting feature - incidentally very useful:
do a trajectory for some future point in time and just let the window sit (do not clear)
hit 'Start' again once a new model run becomes available
since the old trajectory is not erased, both (or all) are shown together on one screen - i.e. you can immediately judge how the wind forecast changes over successive model runs
That is super useful for Alps crossings - we need something between 340 deg NW and 10 deg NE to make it across quickly enough and still hit the Po valley
since usually such a crossing is planned days in advance (like 5) the trend in forecast changes is essential even if things looked good initially
nice animations made possible with the traj plugin:
mhaberler | Premium last edited by mhaberler
@rittels is doing a superb job on the traj plugin (currently at 0.2.8) - it is progressing very fast
I'm just Joe User here, so let me give you an example where things stand and others can reproduce -
- a balloon ride starting July 11local at my home in Stiwoll, Austria
- simulate all flight levels up to FL180
- simulate with all three available models: ECMWF, ICON-EU and GFS
- do this without simulated ascent/descent
- do this with 3m/s ascent and descent
- save the resulting GPX files (2 sets of 3 files)
- convert those to KML with https://www.gpsvisualizer.com/map_input?form=googleearth
- load the kmz's into Google Earth and screenshot those
all artefacts can be found here: http://static.mah.priv.at/traj/0.2.8/
Google Earth screenshots without ascent/descent simulation:
with 3m/s ascent and descent:
gpsvisualizer parameter settings:
(the spam checker flagged the second image as spam - see directly at http://static.mah.priv.at/traj/0.2.8/)
Now allows backward trajectory. still a bit buggy
0.4.4 latest: Fixed error in time interpolation.
I have a lot more confidence in the lowlevel trajectories with 0.4.5:
very good fit with particle animation now!
semi-related: I wrote up a tutorial on Alps crossings with a hot air balloon as there is next to zero material available on the issue
it gives an idea of the meteorological prerequisites: http://static.mah.priv.at/public/alpcrossing/assets/player/KeynoteDHTMLPlayer.html#0
(suggestions for improvement and bug reports welcome)
Here is a comparison of forecast versus actual GPS track - the flight was mostly at 600-700m altitude, meaning the red and orange forecast trajectories apply
The match is simply amazing!
Here's a short tutorial on creating trajectories with windy and the traj plugin:
The Gordon Bennet Cup is coming up in early September - it's the most prestigious competition for gas balloon pilots. Balloons stay up for 3-4 days and the team which flew the longest distance wins.
Meteo forecasting is important - so there's support on the ground helping the pilots decide.
This year, several teams will be supported by a "weatherman" who uses the windy traj plugin for forecasting!
If everything goes well, after the event we should have the forecast and actual tracks flown, giving an idea how well this works for loooong flights.
Here is a case study on forecast with the traj plugin, versus track actually flown with a hot air balloon
This might help with weather briefings at aviation events: https://blog.mah.priv.at/index.php/2019/08/12/displaying-trajectories-for-the-masses/
I'm attending another ballooning event in Austria: http://www.airfield-krems.eu/index.php/ballonfahren/ballon-news
The organizer asked me to provide trajectories for the event, I'm posting those here: https://blog.mah.priv.at/index.php/langenloiser-ballontage-2019/
Here's something neat: visualize an expected balloon flight in 3D based on a windy trajectory:
The GPX file was created with windy.com and the traj plugin. It includes an ascent and descent phase of 2m/s and level flight at 1500m. The GPX file was then uploaded to ayvri.com (free account required).
The ayvri visualization is based on cesium.js - for the curious, play here: https://cesiumjs.org/Cesium/Apps/Sandcastle/index.html?src=CZML Path.html
I wrote a blog post on the latest version of @rittels traj plugin - a huge improvement in functions and usability!
The most prestigious gas balloon race in the world is the annual Gordon Bennet Cup
Pilots stay aloft for several days and might cross the continent
To get an idea, here's a video of the tracks flown this year:
The teams have (and need!) a ground crew which advises pilots on weather and tactics
This year, windy and traj were part of the games - in the ground support for the Belgian, Spanish and US teams - Kolja Packard wrote up a field report (he was part of the support team and worked the weather forecasts):
(this is still german-only, I will post an english translation shortly and notify here):
In particular, have a look at the very first image in the blog post - this was the track forecast 20 hours (!) before takeoff
compare that to the youtube video above - the match is amazing!
Many thanks to Kolja in writing this up!
@mhaberler Really, really very cool. Thanks Michael and Kolja.
Here is the field report in english: https://blog.mah.priv.at/index.php/2019/10/02/field-report-using-windy-at-the-gordon-bennet-cup/
the match of forecast vs tracks flown is pretty phenomenal - remember, the forecast was done 22hrs before takeoff and 80hrs lookahead:
I wrote up some notes on @rittels recently updated traj plugin: