Hi all. I model a staircase, on my sketch on the top view I drew the sketch. The stride line in the center of the staircase is composed of straight lines and curves but could in some cases be splines and straight lines. I'm trying to divide my stride line equally and I can't find the way to do it. Thank you in advance for your help
Hello, I'm not sure I understood correctly but you can section the lines (or curves.. ) via right click > sketch tool >split,
For equal lengths, I think it is feasible via an equation in trajectory length (but I doubt the principle because there will be several degrees of freedom and the sketch will certainly lose its shape),
Hello@Ljp
What is + important is above all to deal with the height of the markets
at least that's what it seems to me
The comfort of a staircase depends on it
@+
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Thank you for the feedback but splitting doesn't work as I hoped. I'm attaching a screenshot to be more explicit. The idea is to divide the stride line into 13 equal parts, composed of three straight lines and two curves
solidworks_copie_ecran.jpg
Hello @Ljp
I just looked at your sketch and I understand why you can't split it since it's not a spline.
So you have to convert your five segments into a continuous line by creating a trajectory.
Once the trajectory is created, you know the length with the measure function divide you by the number of walk minus one. After placing points spaced the desired value apart on the trajectory and you have your bearings.
Since your sketch appears to be 2D, you'll have another problem to solve anyway
Kind regards
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Since it's for a scouting, an idea came to my mind, why not trick with a repetition of bodies (possible body to be deleted at the end),
capture.png
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Hello @Ljp
I propose a 2-step procedure:
-1- Select the entities of the sketch that constitute the projection of the stride line.
Select [Tools], [Spline Tools], [Adjust Spline].
A single spline is constructed fitted "as closely as possible" to the entities of the sketch.
The "Tolerance" parameter defines the maximum allowable distance between the spline and these entities.
-2- Select [Tools], [Sketching Tools] and [Segments]. Select the spline and indicate the number of steps (segments).
Attention: the points are not equidistant, it is the lengths of the spline arcs that are identical.
Kind regards
lignefoulee.png
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Great thanks, I'll test all three options tomorrow morning to compare and learn your different techniques. When Zozo-mp you say "Since your sketch seems to be 2D you'll have another problem to solve anyway" I guess the ideal would have been to make a 3D sketch, but it's a tool that I didn't really understand how it works, but that's on the agenda. For now I have in mind to create a reference plane for each step and on each plan make a sketch to draw the corresponding step. But following our exchanges, I think that my approach is linked to an Autocadian logic and that it would perhaps be more effective to think immediately in 3 dimensions.
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Good evening @m.blt
Something escapes me!
I followed your method which makes it easy to have the number of segments you want. I came up with your result (not without effort because something doesn't make much sense in SW) because what is redefined as a generic spline can no longer be modified like a classic spline. This transforms the initial sketch into a pseudo spline, but it becomes immodifiable (no handles, no ctrl polygon.), the only advantage is to be able to cut it into segments, which I can't do with the technique I proposed above.
Do you have an explanation please!
I'm in V 2019
CDLT
Hello @Zozo_mp,
No real explanation, just a few observations...
Two features are necessary to make the most of the stairway's stride:
- Create a single curve based on a few basic entities: line segments, arcs of circles, parabolas, or other curves.
- divide this curve into segments of equal lengths.
It is also possible to automatically reflect any changes in the shape of the basic entities on the curve and its division into segments.
A quick review of the properties of SolidWorks Adjusted Splines ...
An adjusted spline curve is constructed based on sketch entities, but does not behave the same as a generic b-spline. In particular, as you indicate:
- no selectable waypoints, therefore movable,
- No access to the control polygon or tangency-curvature handles to manage the shape.
The only way to modify the spline is to act on the sketch entities that were used to build it. And again...
When creating an adjusted spline, if the Delete Geometry checkbox is selected, the entities used to define it are deleted. The adjusted spline can then be moved (translation/rotation), but not distorted.
If the Delete geometry checkbox is not selected, 3 options are provided:
- FIXED: the curve created is frozen in its shape and stationary. Subsequent modifications of the basic entities have no effect, the spline remains fixed in its space;
- CONSTRAINT: The curve created is constrained by the base entities. Its shape follows the modifications of these entities (with the deviation tolerance);
- UNCONSTRAINED: the curve is created on the base entities, but without any constraints with them, so without the possibility of following changes. However, it can be moved (translation/rotation).
Unsurprisingly, the option that seems to be the most suitable for the stride line of a staircase is the CONSTRAINT option which allows the curve to follow the changes. However, there is one drawback: the division into segments creates points on the spline by dividing it into arcs of constant lengths. But the points created are not constrained on the curve, and the division is lost if the base features are changed.
I don't see a "perfect" solution to split the stride line using an adjusted spline...
Perhaps the best thing to do is to construct a generic b-spline through the endpoints of the base features, and to add "by hand" constraints to approximate the shape. On a sketch made up of a few segments of lines and arcs of circles, the construction is quite fast and the deviation relatively small.
With such a b-spline, the curve follows the modifications of the basic features (waypoints) quite faithfully , but can lose some properties, especially of curvature. On the other hand, it can be quickly adjusted by acting on the numerical values of the handles (orientation of tangents and curvatures upstream and downstream at the crossing points). An important advantage is that division retains the property of curvilinear equidistance of the points.
Kind regards...
Hello @m.blt
Thank you for the explanation!
In any case, you have to wait until the requester has switched to a 3D spline because the changes in direction in the angles are not trivial for the stride line.
I let the licensed scalers give their advice ;-)
Kind regards
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Hello and a big thank you to you.
So my problem is solved, my stride line is divided into equal parts. I tested your different techniques, especially the two types of splines. I started to test the 3D sketch, but this one seems much more complex to me.