@Chris_G,
I had some thoughts in; Re: Sketcher: Bezier curves 162042
Abdullah replied with a suggestion to check your script/macro; Re: Sketcher: Bezier curves 162072
you wrote; Re: Sketcher: Bezier curves 158220
any thoughts around my thoughts?
Acceleration or forces vs Bezier curves
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- Pauvres_honteux
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Re: Acceleration or forces vs Bezier curves
Hi,
I am probably not very qualified to answer to this.
But I have read that roller coasters, train "roads", are designed so that they minimize curvature ( that is, I think, centrifugal acceleration ).
The comb plot included into the Sketcher BSpline curve tool can indeed help visualize the curvature flow.
In that case you'll want to model your curve with lowest possible variations of the comb plot.
But that is "freehand" design, while the projects you are referring, are, I think, solved by accurate calculation.
Chris
I am probably not very qualified to answer to this.
But I have read that roller coasters, train "roads", are designed so that they minimize curvature ( that is, I think, centrifugal acceleration ).
The comb plot included into the Sketcher BSpline curve tool can indeed help visualize the curvature flow.
In that case you'll want to model your curve with lowest possible variations of the comb plot.
But that is "freehand" design, while the projects you are referring, are, I think, solved by accurate calculation.
Chris
- Pauvres_honteux
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- Joined: Sun Feb 16, 2014 12:05 am
- Location: Far side of the moon
Re: Acceleration or forces vs Bezier curves
Okey, I understand what you write.
What do you say about the possibility to show a value per "vally" and "peak"? It really would go a long way, anyway!
As a bonus one would see, by a glance, if two geometric elements have the whished for transition between them.
What do you say about the possibility to show a value per "vally" and "peak"? It really would go a long way, anyway!
As a bonus one would see, by a glance, if two geometric elements have the whished for transition between them.
Re: Acceleration or forces vs Bezier curves
I'm not sure that the numerical values of the curvature are really meaningful in curve design usecase.
I don't even know what is the unit of a curvature value.
In my comb plot tool, the curvature values are scaled according to the edge length.
So, indeed, if you want to compare the comb plots of 2 edges, they need to share the same scale factor.
So you can either select multiple edges to create a unique comb plot object for all of them.
Or you can select several comb plot objects and apply a common scale factor to all of them :
And it is also possible to select an existing comb plot object and additional edges and run the tool again, so that the additional edges are added to this existing comb plot.
I don't even know what is the unit of a curvature value.
In my comb plot tool, the curvature values are scaled according to the edge length.
So, indeed, if you want to compare the comb plots of 2 edges, they need to share the same scale factor.
So you can either select multiple edges to create a unique comb plot object for all of them.
Or you can select several comb plot objects and apply a common scale factor to all of them :
And it is also possible to select an existing comb plot object and additional edges and run the tool again, so that the additional edges are added to this existing comb plot.
- microelly2
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Re: Acceleration or forces vs Bezier curves
The inverse of the curvature is the radius of a circle arc approximation of the small curve segment at a point.Chris_G wrote:I'm not sure that the numerical values of the curvature are really meaningful in curve design usecase.
It makes sense to lower bound this radius if you bend the material and want not to break it.