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ptstudio
07-06-2015, 09:41 PM
Hello All,

it has been a while since I posted here.

I'm looking for the best method to calculate accurate volume from a 3D model with irregular edges. Think in terms of a machine with various parts and I'd need to calculate the volume of various parts of the machine as well as the whole machine. The machine components are made of cylinders, irregular boxes and other details and irregularities (not simple cubes).

I prefer modeling/working in Lightwave but a friend has used Rhino and finds this task easy, and a few others I know regularly do this in their CAD programs. Is Lightwave CAD capable of breaking down the areas of a lightwave model and calculating the volume of that model? I'd like to a number of these so a fairly easy method would definitely be prefered.

Any thoughts on what the easiest method/programs for this would be?

TIA

Best,

Pat Turner

spherical
07-06-2015, 11:02 PM
Yes, CAD applications deal with this all the time. AutoCAD has a Fill computation that takes a model shape of a depression (a pond) and determines how much infill material it will take to level it with dirt... or water... or concrete. IIRC, LWCAD doesn't have this type of computation, as it doesn't get into that area of land calculations. Might look at FreeCAD and BricsCAD for alternatives.

ptstudio
07-07-2015, 12:31 AM
Thanks Spherical. I'll check that out. I had LWCAD some versions ago but didn't follow the upgrade trail as I didn't use it much. Thanks for the heads up on the other apps.

Pat

Thomas Leitner
07-07-2015, 04:52 AM
Hi,
I donīt know how acurate this is and if itīs works anymore:

http://home.comcast.net/~erniew/getstuff/areavol.html

ciao
Thomas

prometheus
07-07-2015, 05:10 AM
Hi,
I donīt know how acurate this is and if itīs works anymore:

http://home.comcast.net/~erniew/getstuff/areavol.html

ciao



Thomas

Dang...you beat me to it by a few minutes...

just found it in the lightwave plugin base ...and it works with lw 11.6.3 at least in both versions..

I checked freecad and mesh lab, none is having it directly in there as I can see, it might be possible with freecad and use the python command
http://forum.freecadweb.org/viewtopic.php?t=7062...

ridasaleeb2
07-07-2015, 06:36 AM
Get it 3D Printed and immerse in water - difference in volume :D

ianr
07-07-2015, 07:07 AM
Hey ridasaleeb 2,
Soory, some greek gentleman has the Rights to that!

50one
07-07-2015, 08:21 AM
Well, you don't have to get it printed, just upload it to shapeways and use the online tools there before the checkout to check the volume/etc.


S

ptstudio
07-07-2015, 10:58 AM
Wow, thank you all.

Go to bed with a question . . . wake up with several answers!
I discussed the Greek solution with the client but hadn't thought of trial-running shapeways.

I'll check out FreeCad but I'm really interested in the areavol plug (thanks Thomas/Prometheus). The plug-in base hadn't even occurred to me. Many thanks on that.

I used to hang out here a lot back at LW 6.5. But buried my head mostly thereafter. I'd forgotten how helpful the crew here can be. Many thanks to you all.

Best to you!

Pat

ptstudio
07-07-2015, 11:37 AM
I spoke too soon,

it appears the areavol plugin is one of the older variety (pre-intel) plugins. It doesn't work in the Mac version of Lightwave 11.6.3 (on Mac Yosemite). I imagine this functionality is incorporated in the LWCad tools?
I believe I recall similar when I was using LWCAD several versions ago.

Thanks,

Pat

prometheus
07-07-2015, 11:46 AM
Wow, thank you all.

Go to bed with a question . . . wake up with several answers!
I discussed the Greek solution with the client but hadn't thought of trial-running shapeways.

I'll check out FreeCad but I'm really interested in the areavol plug (thanks Thomas/Prometheus). The plug-in base hadn't even occurred to me. Many thanks on that.

I used to hang out here a lot back at LW 6.5. But buried my head mostly thereafter. I'd forgotten how helpful the crew here can be. Many thanks to you all.

Best to you!

Pat


The lightwave database plugin is a must to have as a browsing tab :) I have it on my firefox browser for direct acess.

Freecad is a bit awkward, it is reminding of solidworks, but solidworks is way easier, I donīt like the way you have to ctrl click to get started with drawing or selecting anything, and the way you adjust dimensions..it seems buggy, when clicking on properties the mm function is highlighted, but if you try to directly change it with numeric pads, it will only change viewports since it is connected with those, so you
have to highlight the dimensions manually..even though they already are...weird bug.

the plugin however...seem to work well in lightwave, and it takes in account thickness if you model with inside hollowness.

I think lwcad has a volume calculate tool as well if you invest in that for other modeling tools as well..
Edited...Oh, just noted that you seem to have had to little use of the older lw cad.

prometheus
07-07-2015, 11:50 AM
I spoke too soon,

it appears the areavol plugin is one of the older variety (pre-intel) plugins. It doesn't work in the Mac version of Lightwave 11.6.3 (on Mac Yosemite). I imagine this functionality is incorporated in the LWCad tools?
I believe I recall similar when I was using LWCAD several versions ago.

Thanks,


Pat


if you still have it...just try it, I think it is there.

prometheus
07-07-2015, 12:01 PM
I just noticed, meshlab is available for free and for mac, not sure if there is some issues with the latest versions though...some warnings on the page.

but anyway, you can go to view, show layer dialog..and there it will show the volume..
Tested on a hollow cube, and the volume measurements are the same with the lightwave plugin volume calculate.
Edited..I forgot, You have to go to filters/quality,measurements and computation,/compute geometric measurements..then it will show up in the layer dialog info.

128862

ptstudio
07-07-2015, 12:02 PM
Hi Prometheus,

Thanks for the help. Yes, I had a LWCAD Version that ran on an older pre-intel Mac (somewhere around 10.7.5). I have two Mac-intel chip workstations now and the Older version CAD won't run on them
and that clever areavol plug seems to be for the older versions of Lighwtave on Mac.

Thanks for the help. As usual, I think I have to spend some money! :-(

Pat

prometheus
07-07-2015, 12:10 PM
Hi Prometheus,

Thanks for the help. Yes, I had a LWCAD Version that ran on an older pre-intel Mac (somewhere around 10.7.5). I have two Mac-intel chip workstations now and the Older version CAD won't run on them
and that clever areavol plug seems to be for the older versions of Lighwtave on Mac.

Thanks for the help. As usual, I think I have to spend some money! :-(


Pat


REad my last post above your last post...guess you missed that...use meshlab.

ptstudio
07-07-2015, 12:45 PM
Hi Prometheus,

thanks on the help. I Dl'd Meshlab and tried out a couple of meshes. . . this may be some help.
Any idea what the unit of measure is?

Pat

prometheus
07-07-2015, 01:00 PM
Hi Prometheus,

thanks on the help. I Dl'd Meshlab and tried out a couple of meshes. . . this may be some help.
Any idea what the unit of measure is?

Pat

these kind of measurements seems unit bounded..or should I say unitless, you need to be aware of the size of the object from starters, if you create a box of 1 meter in modeler, and thicken it -10cm

the volume will be 0,30795 cubicmeters...if exported to meshlab, you will only get the unit numbers, which of course is the same...0,30795...so by that it means 0,30795 cubicmeters, you simply only have to add cubicmeters to what ever value you get...I think, since volumes most commonly is described in cubicmeters, I do suck at maths by the way..but hey, so did einstein at one time I think.

ptstudio
07-07-2015, 01:54 PM
Thanks Prometheus,

maths. . . you and me both.

Thanks on this. It should be useful and free is always good. I appreciate all your help.

Many thanks,

Pat