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Recumbent tadpole trike: Posts on Velomobilforum p.5

Recumbent tadpole trike: Posts on Velomobilforum p.5

Hello Titan Wolf, Hein, and sheng fui,

I think perhaps I will post the American version of this on my blog at https://dichotomyone.blogspot.com/
and post the German one here for ease of use by the mostly German viewers here at the Velomobilforum. It should be better for anyone who prefers German and the American version will only be a click away.

Sheng fui will have to let me know if the translation is better with deepl than it is with google translate since that is what I last used for translation.

Hein I think you had a point about lash. Without self balancing geometry that is exactly what would happen without a control system for the tilt. The comments below are also for you and anyone else that may be interested.


Wolf I have been looking around and thinking about your note and have a couple of more comments. I am not sure I completely understand what you where getting at but I took a couple of things for granted in the presentation of the idea for tilting. The first thing is this trapezoid would still be pinned between two sets of uprights and would not be able to move front to back. The tilting would only happen through the Y-Z plane ( X=left-right, Y=front-back, Z=up-down). The second thing is that there would have to be a way of moving the tilt left and right. I think your comment about adding the tilt to the steering system, as a kind of add on, is exactly the kind of thing needed to control the tilt. I only addressed holding the tilt using a braking system during movement to try to avoid the very issues you noted about progressive instability in the wheels themselves as they wobble. There must be a controlled shift, side to side, tilting unless there is a very unique self balancing geometry imposed on the vehicle. I do not claim that sort of insight into these geometries. The following picture shows a cargo trike with tilting and a braking system for it but it does have a tilt control system. The control is visible in the middle below the brake.  




So my challenge is to think of a way to integrate control of tilting with the XYZ Spaceframe system.

I do have one insight that may have been obvious to others…. If the wheels tilt but the trike does not will the trike be steerable at all? I think the proposed tilt mechanism will not tilt the whole trike but just the wheels. Seems odd... but that is what it looks like. I don’t think this will work at all without allowing the whole vehicle to tilt along with the wheels. LOL… so I learn.

What I also noted on other tilting trikes is some of them used a dynamic spring and shock absorbing system to keep the trike upright and meta-stable in normal use. The trike would tilt but it took the force of a turn or a leaning event to get it to tilt. That seems a useful idea.

I may have another sketch built for another time with a better tilting add on for this trike. I hope this jumble of thoughts makes some sort of sense.
So till latter.
Ceeann 

Reply From sheng-fui
It seems to me that the translation is very meaningful. But since my English is not so good, please let others judge it better...... thx for your ideas
perhaps for more ideas have a look at www.chike.de there are some vids in rough terrain and on a skater parc near by me

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