# Help with tangential bicycle wheel

Hello,

We are a group of civilengineering students creating a sports arena with a tangential bicycle wheel for the structure under the roof.

So far, we have created it as such, where the pipes were created with Grasshopper, but every line were drawn in hand. Is there an easier way to create a script that creates a circle with a set radius and an x-amounts of lines going from one part of the outer ring to the other part of the outer ring. After it had created the whole scenario it should look like my picture, but i would be able to edit it?

Every line from outer to outer ring i split, so i can have one line going in the top of the â€ścylinderâ€ť in the middle and on in the bottom. Where every line intersects i have drawn a line/strut as it would support the structure

Best
Mathias

Post. Your. Code

Hi Ftzuk,

Thatâ€™s the problem, i do not have code. I drew it all by hand. I only made the thickness in Grasshopper

We have not gotten an introduction to Grasshopper yet, so i am quite new to the tool

Hope that helps

Maybe post your Rhino file then so itâ€™s easier to see exactly what youâ€™re after. It looks like most of that design can be patterned.

Hi

Tangential bicycle.3dm (4.7 MB)

5 Likes

You sir, are magnificent

Thank you, so much

Have a good day!

Hi Mathias,

Just for fun, hereâ€™s a different approach - not necessarily better - which works by connecting across from one point on the rim to another as you specified, rather than defining an inner circle, so mirrors what you did.

You can specify radius, number of points on the rim, hub height and lace pattern (the number of intervals around the rim between the ends of an aligned pair of spokes). You can specify separate radii for the pipes for the spokes, struts and rim.

And thinking about the practicalities of fabrication, I have included options to spread out the four spoke ends, that come together at a point on the rim, horizontally, vertically and radially. This will allow you to avoid long overlaps. The spread maintains the linearity between ends in plan.

I will leave you and you colleagues to consider how to add connector definitions to the script (and indeed how to split the spokes and incorporate connectors at all the other intersections) once you have learnt more about Grasshopper. That should prove an excellent exercise for honing your skills.

symmetric wheel.gh (37.4 KB)

Regards
Jeremy

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Slightly off topic maybe, but I saw this recently and thought it was neat. It does go into spoke arrangements a bit (around 3/4 of the way down the page)

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Dear Jeremy,

This is really good, thank you. It allows for more possibilities and i will for sure show this to the rest of the group.

I really appreciate you, for taking the time to further come up with solutions. Thank you!

Best
Mathias and the group

Super interesting page!

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Dear Daniel,

This was not off-topic at all. A very interesting read (and quite entertaining with the illustrations)

This helped a lot, as i didnâ€™t actually know that much about bicycle wheels before doing this task and if i had seen this page before all the other pages trying to enlighten me, I would have saved a lot of time

Thank you for this!

Best
Mathias and the group

1 Like

Be careful of over-pressing the analogy: the forces on your structure will be quite different. For example you will have the weight of a roof structure and, perhaps, an associated snow load acting across your spokes.