Units/mass issue

Dear Peregrine experts,

First of all, I wanted to thank LimitState for providing such an early technology demonstrator and for their interest in providing free academic versions.

I´m obtaining a very high optimised mass and too thick members for some simple load case. Briefly, I´m trying to optimise a 1 m long truss that is axially loaded with 24 kN compression force (about 2450 kg) and pinned at both ends. However, using standard steel material properties (Stiffness: 210 GPa, Strength: 355 (both compression and tension), Poisson: 0.3, and Density: 7850 kg/m^3) I obtain an abnormally high volume of 7.11211·10^7 mm^3, i.e. around mass around 558 kg, and really thick members. This is simply senseless… Would you check what´s wrong? TrussTest.gh (33.4 KB)

I´ve checked that Rhino units are “meters” and ProbSpec´s Unit output says “m”, so both seem to be the same. I´m running Rhino version 6 SR11 (6.11.18275.16081, 10/02/2018), Grasshopper version Tuesday 02 October 2018 16:04 Build 1.0.007, and Peregrine 3.50.0.8043.

Would it be some kind of issue in units management between Rhino and Peregrine? Or, more likely, am I doing something wrong?

By the way, the text in dialog boxes (those that appear upon double-click in e.g. “ProbSpec” object) appears partially hides the input field box. For example, the Effective Euler buckling length is hidden in my display, and I can just barely see the Euler Buckling checkbox. I´ve observed that something similar happens for “Mat” object.

Hi Vigardo,

Thanks for the feedback.

Regarding the issue with the volume. The load magnitude should be defined in kN, rather than N as has been done in the file. It could possibly be clearer that this is the case though, so I’ll pass a note on to the developers to see if there is any way this can be highlighted.

Regarding the dialog boxes, I’ll mention this to the developers also (it would be good to know what screen resolution your monitor is set at). In the interim, you should be able to resize the dialogs to expose the obscured fields by using the handle at the bottom right of the box.

Regards,

Tom

2 Likes

Thank you very much Tom for the rapid response!

Now, by considering kN in the forces results look nice.

I already tried to resize the dialog boxes, but despite the window itself resizes the text and form fields do not. My screen resolution is 1920x1080.

Hi Vigardo,

Are you able to let us know a little more about your OS and settings? Specifically, it would be useful to know which version of Windows you’re running and what font scaling settings (if any) are applied. The latter can be seen in the Windows Display Settings dialog. If you could email us a screenshot of what you’re experiencing too, that would be helpful.

Regards,

Tom

1 Like

Hi Tom, sorry for the delay.

I´ve checked the “Scale and Layout” Windows settings and for some reason I had 150%… When I reduce it to 125% the problem solves. Thanks!

This was the issue:

Hi Vigardo,

Thanks for letting us know!