Wednesday, 20 January 2021

Explaining tetrapter flight (Tetrapters/tetropters X)

Just a short post this time. 

The Book will not only contain paintings of animals, plants, mixotrophs and people, but will also contain explanatory diagrams. These are usually much more boring to produce than texts or paintings, but they still have to be done... I had postponed writing and illustrating the flight of tetrapters for quite some time, and have now decided to get to work and not to look up until it is done. 

The challenge here was how I could capture the complexity of tetrapter flight in static diagrams, although I already had videos dynamically showing how tetrapters move their wings. The two diagrams above form part of a set of eight. Together they depict one complete movement cycle. I decided that I would show the path of the tip of the wing in the diagram, and that a portion of the path would be shown with a bold line, to indicate the movement since the preceding diagram. I hope that works.

Click to enlarge; copyright Gert van Dijk

Click to enlarge; copyright Gert van Dijk

The two diagrams show the point in time where the wings are moving apart after the 'clap' phase, when they touch or nearly touch. When they then 'fling' away, they create the 'clap and fling' mechanism that provides part of the lift. For more on that, you may read some older posts indicated by their year of publication: 2009a, 2009b, 2011 and 2018


Click to enlarge; copyright Gert van Dijk

 By the way, I have started to update the main Furaha website. I will gradually add some new material, but do not want to give away too much of the content of The Book. Still, some newer paintings will creep in here and there. I changed the image on the welcome screen, and do not think I ever published that particular rusp image before. So there you are.