Hi,

I wanted to try out MoI but I'm having problems. I can do this in Rhino, so I know it can work in general. I have a file with airfoil points and another file with rail points. They are xyz files. I import both files and do a two rail sweep to make the blade. At least that's what I do in Rhino. I can't get past the first part in MoI. I installed the import point file script but it gives me an error. I was wondering if someone can look things over and let me know what's wrong. I don't know if it doesn't like the number format. Also for the rail file there are three different lines. Rhino imports all the points but I don't know if MoI would need to have each set of points in its own file.

I added the shortcut Ctrl+I ImportPointFile as described in the instructions on Peter's website.

Please see attachments for more info.

Thanks for your help,

Anthony

Edit; Attachments have been removed.

Hi Anthony,
I think the error may be because your file is "starting with spaces"??? Or doesnt have a wellformed delimter (Like it's just a fixed width or something)

Here's your file back where I just opened it in excel and resaved it (Using comma's but this doesnt matter)

In excel, I can say it is a "space delimited" file, but I can also say "Treat consecutive delimiters as one" which packs all those spaces down to just one for a column.

Do you know how this file is deliminated??

Hi Anthony - it looks like the problem is that the import script is expecting for the x y z coordinates to only be separated by a single space instead of multiple space characters.

If you open up your .xyz file in a text editor like notepad or something, you can see that the numbers have been formatted with multiple spaces in between the individual coordinates, I guess to make them look more human readable.

I should be able to tweak the script to allow for that though, I'll take a look.

- Michael

Hi Burr,

> Do you know how this file is deliminated??

It's space delimited, but with a variable number of spaces instead of just one space - it's that variable number of spaces that is throwing the import script off. The current import script wants just one delimiter character in between each coordinate.

- Michael

Top of the morning to you Gibson!

And to you Burr! :)

Hi Anthony, I've attached here an updated version of the script which should now import these files ok - this version handles multiple spaces between each coordinate.

You'll need to set the Delimiters: option in the command to "Spaces" here:



and then the only other thing is that these points are at a pretty small scale - they fit in a box something like 0.03 units across, so you'll need to zoom in to see them well. You can zoom to see them by doing a right-click on the "Reset" button in the toolbar that's at the bottom of any viewport.

You'll probably want to scale them up before working with them.

- Michael

Wow,

Thanks for the fast response and all the help. I'm really glad I asked. I was stumped. I never would have figured that out. Also, thanks for updating the script. I will try it out asap. The file is default formatting from gfortran. I don't specify anything about it. The program I wrote just generates it like that. I didn't know there were extra spaces.

Anthony

The updated script works great. I'm having a few issues though. It seems like MoI won't sweep an arc or radii. I have the airfoil and most of the surfaces but there is no trailing edge or leading edge radius. I tried a few different things but can't figure it out.

Hi Anthony, I'm sorry but I'm not sure what you mean by "MoI won't sweep an arc or radii" - could you please post a 3DM model file that has the arc in it that you're trying to sweep so I can see what you're trying to do?

- Michael

I'll have to install the 30day trial. I had installed the no save version. It is hard to explain. I have an airfoil. I import the points and then make curves from the points. The leading and trailing edges are made with arcs. When I try to do a two rail sweep it won't sweep the arcs. Its ok with the splines. Give me awhile to install the other version and make a file that may help to clear it up some.

On a side note I'm having trouble with the trim. It doesn't seem to work for me. I found a work around, but just wondering why I can't get it to work.

Hi Anthony,

> It doesn't seem to work for me. I found a work around, but
> just wondering why I can't get it to work.

Well, there are a number of possible reasons - like for example if the cutting object does not intersect the thing you're trying to trim it won't produce any result. Or if you have a curve that intersects a surface it must cut the surface into 2 complete pieces you can't trim with a cutting curve that looks like this for example:



It's pretty much impossible for me to know what particular problem you might be running into without actually seeing the model file that you're working with.

- Michael

Thanks,

I have a circle I'm trying to trim with two points. Here is the file you requested regarding the other issue. This works in rhino. If you select one side of the airfoil curve and do a two rail sweep MoI won't sweep the arcs, just the spline. I have tried a few different things but I can't get it to sweep the leading and trailing edges of the airfoil. You have to zoom in a lot to see the trailing edge, its very small. I have it set up exactly like rhino has to have it. I had to fight a lot with rhino to figure out what it needed. I'm fine with having to do it a different way, but I made the file to make it as easy as possible for you to see what I mean.

Anthony

Edit; Attachments have been removed.

Is this the shape you wanted??

Join these 2 edges then sweep the 2 rails:

If you select one arsc the sweep 2 rails works
If you select the other arc the sweep 2 rails works

If you join the 2 arcs the sweep 2 Rail works

If you select the 2 arcs (not joined) the Sweep 2 rails don't works
(posted in the same time :)

hi,

yes that is the shape. when you zoom in does yours actually have leading and trailing edge surfaces. from a distance it looks like they are there but when you zoom in there is a blank. at least for me. let me try this again as it seems you guys are having some success.

thanks again

Oooops prop, looks like my example missed one of the little arcs at the bottom for the join.. I'll review it and repost.

Hi Prop,
Yes I saww the problem you just described...Here is a file with the sweep as i think you wanted it..

I'm not exactly sure about one of the issues, and will wait for Michael to chime in.

First, the scale of the model may have been presenting issues for the tolerances in the file.. FOr instance, that little arc on top is something like .0067 in diameter..

I scaled your model up by 100 times, then tried the sweep. I still had an issue in that little top arc area with a malformed surface creation.. So I ran seperate on the 2 original profiles and seperated out that little arc on both ends (Perhaps they were joined with the small values and didnt get a good join in???) Then I used the 3 point arc command and recreated those 2 end arcs and deleted the old ones. Then I joined the whole lot and did the sweep as described before...

Then I scaled it by .01 and will attach it here.

hi, thanks now I know I'm not crazy. what you found makes sense based on my experience with rhino. I had to fight with it a long time before I got it to work. and it all boiled down to tolerance settings and mesh options mostly.

I see moi is way better in a lot of ways and can really save some time if I can figure it all out. you came up with a really smart solution I wouldn't have thought of, scaling up and then back down. I should mention all points are in meters.

Hi Anthony re: Trim -

> I have a circle I'm trying to trim with two points.

Could you post the particular circle and the 2 points in a 3DM file so I can take a look at your specific case?

Trim does work in general with a circle and 2 points - for example here I've created a circle and 2 points on it, and used the Trim command to cut away a part of it:







If it doesn't work from you possibly the points are not on the circle or something like that? It's hard for me to know what the issue might be without seeing the model file though.

- Michael