Any way of Carrara working out the surface area of an object?

HeadwaxHeadwax Posts: 10,013
edited December 2023 in Carrara Discussion

Hi Brain Bank :)

 say I have a flat irregular plane (think a surfboard fin plan or a random shape).

Was wondering if there was any way in Carrara to get an automatic area measurement of it - rather then counting sq cm's by eyeball?

 

thanks in advance ;)

Post edited by Headwax on

Comments

  • WendyLuvsCatzWendyLuvsCatz Posts: 38,309
    edited December 2023

    a 3D printer slicer program should do this

    Meshmixer could do it if you still have that

    Post edited by WendyLuvsCatz on
  • HeadwaxHeadwax Posts: 10,013

    thanks Wendy, will check in those, was hoping carrara had a hidden talent ;)

  • Bunyip02Bunyip02 Posts: 8,711
    edited December 2023

    Do you have a CAD program ?

    Did a screenshot of your pic, saved as jpg.

    Opened CAD, went to Insert an image

    Once image was in drew a reference line and obtained the length

    Worked out the scale ratio assumming a 15cm length

    Applied scale to inserted image

    Drew a Polyline around the fin

    Clicked on Polyline to get the Area, which was 74.084 cm2

    EDIT - LibreCAD is free, was able to get a Polyline area out of it but was not as User-friendly as CorelCAD which I obtained through a Humble Bundle package.

    CAD 1.png
    1903 x 924 - 1M
    Post edited by Bunyip02 on
  • Bunyip02Bunyip02 Posts: 8,711
    edited December 2023

    LibreCad - just tried exporting a cube primitive from Carrara as a dxf file.

    LibreCAD can import a Block which is a dxf file. File - Import - Block

    Then Tools - Info - Polygonal Area - trace around the area you want, and read off the Area value in the Command Line

    If you need more details about this method just yell !!!

    LibreCAD dxf area 1.png
    1918 x 1035 - 99K
    Post edited by Bunyip02 on
  • Bunyip02Bunyip02 Posts: 8,711
    edited December 2023

    Polygon Trial

    Quick Carrara model

    LibreCAD

    NOTE - I have not checked any issues with unit differences in the conversion, will do if you are interested ....

    DXF 1.png
    2263 x 1033 - 474K
    DXF 2.png
    1921 x 1040 - 121K
    Post edited by Bunyip02 on
  • HeadwaxHeadwax Posts: 10,013

    Thanks Bunyip 02 :) Very kind of you to go to all that trouble and making such a clear walk through! . Ah the areas just need to be relative rather than absolute. The idea is to compare fin areas, so to take a planshape and tweak it but still keep the same overall area.

    I have a few free cad programs plus amateur autocad, I'll check those out ! Thanks for the idea and I'll keep an eye out for humble bundle corel cad.

    I see they are doing Christmassy things at the moment.

    Bloody hot today!

  • StezzaStezza Posts: 8,133

    ahh... you need to find the area under a curve and above the x-axis modeled by function f(x) in the domain interval x within [a,b]. This method requires knowledge of integral calculus.

    this little duck has NFI cool

  • HeadwaxHeadwax Posts: 10,013

    Stezza said:

    ahh... you need to find the area under a curve and above the x-axis modeled by function f(x) in the domain interval x within [a,b]. This method requires knowledge of integral calculus.

    this little duck has NFI cool

     

    ha ha you sound like the research gate papers I have been reading on aerodynamics for the last two months - people get grants for anything - like some guys figured out if you put more support under the part where you stand on a hollow surfbaord then it flexes less :)

     

  • HeadwaxHeadwax Posts: 10,013
    edited December 2023

    random pic showing vortex generators (left fin) and passive leading edge slots  (both fins)  - carefully sanded ha ha 

    the little holes at the rear of left  fin are supposed to be for inducing a passive venturi to reattache the laminar boundary layer at high angles of attack - well that wa s my idea anyway ;)

    let you know if it works  (probably work better if I sanded themproperly)

     

    the grooves are supposed to interrupt the spanwise flow and reduce the induced vortex drag coming off the tip where the high and low pressure ares try to mingle - kind of like winglets on air-o-planes

     

    20231206_180942.jpg
    4128 x 3096 - 3M
    Post edited by Headwax on
  • be careful mate heart

    lots of sharks munching on people lately

  • HeadwaxHeadwax Posts: 10,013

    WendyLuvsCatz said:

    be careful mate heart

    lots of sharks munching on people lately

    I have the new invisability cloak the Chinese just invented :) Thanks for the warning. Had a surf tother day surrounded by about  thirty dolphins and their babies . That was interesting. The buggers never look where they are going. Too busy showing off

  • HeadwaxHeadwax Posts: 10,013

    Hi Wendy did you mean Meshlab? found this How to Measure Surface Area of a Mesh | Foundry Community   - you need to divide by two to get the correct answer in sq cm ?

    Couldn't see in in my Cura slicer though

  • Bunyip02Bunyip02 Posts: 8,711
    edited December 2023

    Headwax said:

    Thanks Bunyip 02 :) Very kind of you to go to all that trouble and making such a clear walk through! . Ah the areas just need to be relative rather than absolute. The idea is to compare fin areas, so to take a planshape and tweak it but still keep the same overall area.

    I have a few free cad programs plus amateur autocad, I'll check those out ! Thanks for the idea and I'll keep an eye out for humble bundle corel cad.

    I see they are doing Christmassy things at the moment.

    Bloody hot today!

    Check that you can import a dxf file in your CAD programs, most will have the Polyline/area hidden away some-where. I used AutoCAD all the time when I was working as a Design Drafter many years ago.

    Meshlab sounds interesting as well.

    Definately hot, been on my laptop as my graphics computer does not like the heat apart from a few hours early in the morning or late at night, and I am not a morning person normally !!!

    Post edited by Bunyip02 on
  • WendyLuvsCatzWendyLuvsCatz Posts: 38,309
    edited December 2023

    possibly both do it

    Meshlab does do a lot of things but it was Meshmixer, I recall it having this function and Google confirms it

    https://meshmixer.com/

    Post edited by WendyLuvsCatz on
  • Bunyip02Bunyip02 Posts: 8,711
    edited December 2023

    Did a comparision of Meshlab and MeshMixer both of which I have installed on my Graphics Computer

    Meshlab

    Edit - Select Faces in a Rectangular Region

    Filters - Quality Measure and Computations - Compute Area/Perimeter of Selection

    MeshMixer - could not find anything obvious for Surface Area, mind you I am only using the program for the first time

     

     

    MeshLab Global Hawk 1.png
    1923 x 1043 - 130K
    MeshMixer Global Hawk 1.png
    796 x 766 - 121K
    Post edited by Bunyip02 on
  • DiomedeDiomede Posts: 15,188
    edited December 2023

    Here is a suggestion for volume of oddly shaped objects that has only a small chance of success - but not crazy talk.  Start with a 1unit x1unit x 1unit cube and stack them vertically to build a tall water tank.  Use a shader to demark the vertical side of the cube in 10 steps or 100, or whatever level of accuracy you need.  Fill with a Fluidos amount of water bigger than your object.  Take your object and lower it into the fluidos tank.  Note how high the water level goes on the calibrated tank.  Subtract the initial level.  Calculate volume of odd shaped object from difference.

    - So much can be wrong about this suggestion!  The internal math of Fluidos might not work this way at all.  Or, the way in which Fluidos simulates the flow of water might not take into account volume of water.  Even if the internal math of Fluidos could work this way in an appropriate program, Carrara physics might not.  I haven't tried this, and I have not used Fluidos enough to have a guess if this would work.

    EDIT:  The metric based world should be able to choose a unit that converts easily to a volume.  Meters to liters, or whatever.

    Post edited by Diomede on
  • under Stability 

  • Bunyip02Bunyip02 Posts: 8,711
    edited December 2023

    Thanks Wendy !!! Not an obvious place to hide it !

    MeshMixer Global Hawk 2.png
    798 x 770 - 101K
    Post edited by Bunyip02 on
  • Bunyip02Bunyip02 Posts: 8,711
    edited December 2023

    Diomede said:

    Here is a suggestion for volume of oddly shaped objects that has only a small chance of success - but not crazy talk.  Start with a 1unit x1unit x 1unit cube and stack them vertically to build a tall water tank.  Use a shader to demark the vertical side of the cube in 10 steps or 100, or whatever level of accuracy you need.  Fill with a Fluidos amount of water bigger than your object.  Take your object and lower it into the fluidos tank.  Note how high the water level goes on the calibrated tank.  Subtract the initial level.  Calculate volume of odd shaped object from difference.

    - So much can be wrong about this suggestion!  The internal math of Fluidos might not work this way at all.  Or, the way in which Fluidos simulates the flow of water might not take into account volume of water.  Even if the internal math of Fluidos could work this way in an appropriate program, Carrara physics might not.  I haven't tried this, and I have not used Fluidos enough to have a guess if this would work.

    EDIT:  The metric based world should be able to choose a unit that converts easily to a volume.  Meters to liters, or whatever.

    Looks like Headwax is spoilt for choices now !!!  - 1 Cubic metre = 1000 Litre

    Post edited by Bunyip02 on
  • StezzaStezza Posts: 8,133

    A typical Australian would use the 'ROE' method. wink

  • cdordonicdordoni Posts: 583

    Deskartes 3D Data expert (free) also has some tools for volume and surface area.

  • HeadwaxHeadwax Posts: 10,013

    WendyLuvsCatz said:

    possibly both do it

    Meshlab does do a lot of things but it was Meshmixer, I recall it having this function and Google confirms it

    https://meshmixer.com/

    thank you Wendy

  • HeadwaxHeadwax Posts: 10,013

    Stezza said:

    A typical Australian would use the 'ROE' method. wink

     

    ha ha I had to google it. I hated maths at uni. The last purely maths thing I did I got 49 out of 50 first semester and 1.5 out of 50 the second semester. So I luckily passed...

  • HeadwaxHeadwax Posts: 10,013

    cdordoni said:

    Deskartes 3D Data expert (free) also has some tools for volume and surface area.

     

    thanks that looks very interesting will check it out ! Deskartes 3D Data expert

  • HeadwaxHeadwax Posts: 10,013

    Bunyip02 said:

    Headwax said:

    Thanks Bunyip 02 :) Very kind of you to go to all that trouble and making such a clear walk through! . Ah the areas just need to be relative rather than absolute. The idea is to compare fin areas, so to take a planshape and tweak it but still keep the same overall area.

    I have a few free cad programs plus amateur autocad, I'll check those out ! Thanks for the idea and I'll keep an eye out for humble bundle corel cad.

    I see they are doing Christmassy things at the moment.

    Bloody hot today!

    Check that you can import a dxf file in your CAD programs, most will have the Polyline/area hidden away some-where. I used AutoCAD all the time when I was working as a Design Drafter many years ago.

    Meshlab sounds interesting as well.

    Definately hot, been on my laptop as my graphics computer does not like the heat apart from a few hours early in the morning or late at night, and I am not a morning person normally !!!

     

    thanks will check that DXF , yes I like to sleep in till 7.00 am but that sun blasts in at 5.30 :( :)

  • HeadwaxHeadwax Posts: 10,013

    Bunyip02 said:

    Diomede said:

    Here is a suggestion for volume of oddly shaped objects that has only a small chance of success - but not crazy talk.  Start with a 1unit x1unit x 1unit cube and stack them vertically to build a tall water tank.  Use a shader to demark the vertical side of the cube in 10 steps or 100, or whatever level of accuracy you need.  Fill with a Fluidos amount of water bigger than your object.  Take your object and lower it into the fluidos tank.  Note how high the water level goes on the calibrated tank.  Subtract the initial level.  Calculate volume of odd shaped object from difference.

    - So much can be wrong about this suggestion!  The internal math of Fluidos might not work this way at all.  Or, the way in which Fluidos simulates the flow of water might not take into account volume of water.  Even if the internal math of Fluidos could work this way in an appropriate program, Carrara physics might not.  I haven't tried this, and I have not used Fluidos enough to have a guess if this would work.

    EDIT:  The metric based world should be able to choose a unit that converts easily to a volume.  Meters to liters, or whatever.

    Looks like Headwax is spoilt for choices now !!!  - 1 Cubic metre = 1000 Litre

     

    thanks for those walkthrough and yes, spoilt for choice! Better than the opposite :)

  • HeadwaxHeadwax Posts: 10,013

    Diomede said:

    Here is a suggestion for volume of oddly shaped objects that has only a small chance of success - but not crazy talk.  Start with a 1unit x1unit x 1unit cube and stack them vertically to build a tall water tank.  Use a shader to demark the vertical side of the cube in 10 steps or 100, or whatever level of accuracy you need.  Fill with a Fluidos amount of water bigger than your object.  Take your object and lower it into the fluidos tank.  Note how high the water level goes on the calibrated tank.  Subtract the initial level.  Calculate volume of odd shaped object from difference.

    - So much can be wrong about this suggestion!  The internal math of Fluidos might not work this way at all.  Or, the way in which Fluidos simulates the flow of water might not take into account volume of water.  Even if the internal math of Fluidos could work this way in an appropriate program, Carrara physics might not.  I haven't tried this, and I have not used Fluidos enough to have a guess if this would work.

    EDIT:  The metric based world should be able to choose a unit that converts easily to a volume.  Meters to liters, or whatever.

     

    wow, that's a bit of lateral thinking! When i get my head around Fluiodos again I will try it :)

  • HeadwaxHeadwax Posts: 10,013

    just ran an obj through meshlab and meshmixer and got the same area - so that's a relief :)

  • StezzaStezza Posts: 8,133

    Stezza said:

    A typical Australian would use the 'ROE' method. wink

    laugh

    = Rack Of Eye 

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