Using "Insert from file"

[jaysinn]

Hi,
I'm a newbie to Alibre but quite fluent with Excel, etc. (In a previous life at work, I used a much more expensive CAD product).

I'd like to create a specific curve shape based on points that I calculate in Excel. This curve would become one "side" of a figure in a 2D sketch. I know how to export these points into a CSV file.

The tool for creating a curve using "Insert from file" is in the 3D sketching domain, and although I can see the curve on my screen, it is inert. I can't connect to it and I can't even "make a drawing" of the part because Alibre considers the curve not closed.

This seems to me to be a missing feature in the program. What good is an inert curve on screen that you can't work with?

I saw another thread on this topic that suggested creating a small box in another plane, and making the box extrude along the curve.. and then somehow extracting the edge of that solid to finally arrive at the desired 2D curve. Besides the fact that that method is a diabolically convoluted workaround for an obvious gap in the program capability, there is also the problem that as a newbie I have no idea how to extract that edge and make a 2D curve out of it.

And somehow I can't even find that thread again. I think there was maybe an add-on answer from "Alex" that was helpful, but when I clicked on the link, I got a "404" error and could not return to the same page.

 

[Jim C]

Almost inert but it does have some use. First of all I’ve found that it is easiest if all points lie on a plane, not necessarily the standard orthogonal ones but a plane you can work with. As an example let the 3D curve lie on the XY plane. The suggestion you recalled is the way that I use. At one end of the curve draw a rectangular sketch on a plane normal to the one with the data and let one edge of the rectangle touch the 3D curve. This is easier if you can make one point reside at the origin or other known reference point. I’ve found that making the rectangle as elongated as possible makes cleanup easier later.

Perform a sweep operation and then open a 2D sketch on a parallel plane to the sweep, in this case the YZ plane. Do a project to sketch using the create sketch figure to get a “shadow” of your curve. Here is where a rectangle comes in handy since a circular sweep doesn’t seem to properly project. You should be able to select the face of the surface produced by the sweep or if your data was imported as line segments you can select each segment and if it was a spline then a single selection will do. You can now remove the unwanted portions of the projected sketch and the remaining sketch should be what you want. Complete the sketch as desired and there you are.

At this point you can delete the sweep operation without affecting the sketch, I hope I wasn’t too long winded or unclear. Best bet is to play with a simple starting sketch and go from there. Sketch 2 in the attachment is the final sketch and needs to be closed or processed as desired. The sweep may be suppressed or deleted.

Hopefully someone has an easier way.

Jim C

 

[jaysinn]

Actually, I guess I was hoping for is what used to be called a "wedge" program. This is a small program that temporarily redirects the "input" to another program from the keyboard to a text file. In other words, if I use Direct Coordinate Entry to specify points on the curve, I can use the keyboard to manually copy the points from my Excel file into Alibre. But why not let Alibre just read a text file instead? It would be faster and more error-proof.

My very old TurboCAD program (back in Windows 98 days) had this capability.

I've tried creating splines using the keyboard in 2-D mode and it seems that the splines created this way do obey the descriptions given in the Help file. They are usable and not "inert."

However, I also note that before you Save a Part, if you evidently must have a 3D part or at least a 2D Sketch with only closed areas. Saving a sketch with floating lines that are not part of the definition of a closed area will result in a Sketch that does not act properly. The splines (even though created in 2D space) cannot be selected or used for anything.

As an alternative, do you think it is possible to "Drive the Design" by using the Excel Alibre add-in? In other words, if I created a spline on-screen just using my mouse to define the points, could I then edit those points to the precise values using the Excel - Alibre linkage? (Unfortunately, I have Excel 2010, not 2007.)

 

[Jim C]

You can read a file directly into Alibre as long as you are in the 3D sketch mode. In the 3D sketch dropdown select Figures and then Insert From File. It doesn’t appear to make any difference as to the extension of the file as long as the file is a comma separated file (CSV). The file can be a two dimensional data set such as the following:

0,1,0
2,2,0
3,1,0
4,4,0
5,3,0

As long as there is X,Y,Z data it seems that this method works well but it has to be just the data. Also it seems that the data can be relatively free form as long as there is the comma separator. That makes it easy to type in your own data or format it using Excel or a data acquisition program.

After you insert the data exit the 3D sketch and here is where the neat feature comes in. Just click on Insert Plane and if need be select the 3D sketch, Alibre will insert a plane that is normal to one end or the other of the sketch. That really makes it easy to make a 2D sketch that defines the cross section of a sweep.

As far as open sketches go I find them useful as guides for subsequent sketches as long as the View Sketches option is enabled. Also 2D open sketches are handy when in a 3D sketch by using the 2D endpoints as nodes for the 3D sketch. If you want to save the file as a part just make a simple sketch, say a circle, extrude a boss and then it will save as a part.

Hope this method is of some use to you, I’ve found it much better than typing in my own data.

Jim C

 

[jaysinn]

Here's something interesting. It doesn't solve the Import From File limitation, but it does allow you to create and save 2-d figures that are not closed, and use them to create Parts. You can create a new, blank Drawing and sketch anything on there that you wish. This Drawing can be saved without any need for there to be a closed surface. In the Drawing, select the entity you have created, Edit-Copy, and then go to a Part sketch where you can Edit-Paste the entity (spline curve or whatever) onto whatever plane you choose. The pasted entity behaves just as if you had sketched it within the Part window.

 

[jaysinn]

In Alibre 24, you can insert points from a comma-separated file into a 2D sketch. There's a little "keyboard" icon in the "Sketch Figures" part of the ribbon.

 

[Oldbelt]

In 2D sketch mode points can be inserted :<Sketch tap> <figures> <insert from file> browse to your file .dat or .txt
x y
1.0 x
2.0 x
3.0 x
no use of excel or comma separation