How to import Catia5 hull shape into UliTank

[heikki]

The UliTank thread is expired so I ask here.

I have a hull shape in CatiaV5 format. How to easiest import it to UliTank?
Also how should origin be placed? UliLines 3.3 manual says it places origin to forward end of water line at the level of water. Tested to create hull shape with same parameters in UliLines 3.3 and the origin on output file seems to be at rear end of water line below water level. The result out of 3.3 differs a bit from the model. Have understood more recent version has more controls to fit the shape.

 

[Remmlinger]

There are different input formats that can be used in UliTank
Did you create an offset table from your Catia-model?
Can you post the input-file that you created for UliTank?
Uli

 

[heikki]

Hello,

I haven't created an offset table from the model as I do not know how to create it automaticly. Ulilines 3.3 seem to be making about 3000 points and manually measuring and infeeding that amount of data to a file is a big job for a hobby. The points given by Ulilines I can feed to Catia with a macro. Hullshape defined by Ulilines 3.3 differs a bit from Catia shape as it has more rocker at the front. I could manually move the points of cross sections of bow vertically so I would be close to original shape. What puzzles me now is where and how origin and axes should be located for Ulitank.

Br: heikki

Attached file generated by Ulilines 3.3 from parameters calculated of Catia-model.

 

[Remmlinger]

Thanks heikki, I am always glad when getting feedback.
If you use UliLines to "recreate" the hull that you have designed in Catia you will never get the same shape, only an approximation with the same overall hull coefficients.
Instead I would recommend, that you create the offset-points directly in your Catia-model. It was 25 years ago when I worked with Catia, so I do not know what Catia offers today to create the points. In the manual I have described the procedure for Rhino, Catia should offer similar tools. May be you can adapt this procedure - create 40 vertical planes - create 40 intersections with the hull - create 40 points on these curves - export the points. In Rhino you can do this in less than 10 minutes.
The origin of the coordinate system can be chosen freely, it must only be on the symmetry-plane. The positive directions are specified in the file UT##in.txt
Good luck, Uli

 

[Alexanov]

The UliTank thread is expired so I ask here.

I have a hull shape in CatiaV5 format. How to easiest import it to UliTank?
Also how should origin be placed? UliLines 3.3 manual says it places origin to forward end of water line at the level of water. Tested to create hull shape with same parameters in UliLines 3.3 and the origin on output file seems to be at rear end of water line below water level. The result out of 3.3 differs a bit from the model. Have understood more recent version has more controls to fit the shape.

Is it possible to import IGES file to UliTank? I am sure you can make IGES from Catia. What kind of files you can import? Most simple way - convert IGES by Rhino to any file type of file sutable for UliTank. Rhino is a great converter for everithing.

 

[heikki]

Iges comes out of Catia easily. Just have to learn Rhino then. On UliTank is Z-axis always normal to waterplane?

BR: heikki

 

[Alexanov]

there is nothing to learn in Rhino - import Iges and save in required file format. I think about 50% of Rhino users just use it for converting files)) Perfect tool for converting.

 

[Remmlinger]

Iges comes out of Catia easily. Just have to learn Rhino then. On UliTank is Z-axis always normal to waterplane?

BR: heikki

Yes, the z-axis is normal to the waterplane.
I do not think that you have to use Rhino to create the offset-file.
There must be a way in Catia to create planes, intersections and points. Compared to Rhino, Catia is is a high-end CAD-system with many more options and tools.
Uli

 

[Alexanov]

Is it only offset table can be import to UliTank?

 

[Remmlinger]

Is it only offset table can be import to UliTank?

Please read the users-manual
Similar to Michlet, UliTank uses a table of offsets to define the hull shape. The offsets must be provided at fixed stations. It makes no difference whether you use Delftship or Rhino or any CAD-System, you have always to define the position of the stations.

 

[Alexanov]

Please read the users-manual
Similar to Michlet, UliTank uses a table of offsets to define the hull shape. The offsets must be provided at fixed stations. It makes no difference whether you use Delftship or Rhino or any CAD-System, you have always to define the position of the stations.

Yes, if it just Offset table we have no choice.