How to measure surface area in mm^ generated using triangulaiton of a 3D object model by Matlab

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M.S. Khan 2020-8-24

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https://ww2.mathworks.cn/matlabcentral/answers/583631-how-to-measure-surface-area-in-mm-generated-using-triangulaiton-of-a-3d-object-model-by-matlab

编辑： Bruno Luong 2020-8-26

I have geneated Cone Model. The cone was generated using radius 78 mm and height 188.4 mm. Using trimesh(), i have triangulated it to measured its suface area. Please help me how to measusre caliberation factor to approxite it surface area or volume. i will be very thankfull for your cooperation and guidance.

Attached are coordinates and the figure of the cone. Thanks for the guidance of KSSV and Uday.

Regards,

bx = Boundary(:,1) ; by = Boundary(:,2) ; bz = Boundary(:,3) ; 
T = delaunay(bx, by)
TO = triangulation(T, bx(:),by(:),bz(:)); 
area = 0; 
for i = 1:size(TO.ConnectivityList,1)   %the number of rows gives the number of triangles produced
    a =  TO.Points(TO.ConnectivityList(i,:),:); %this gives the 3 vertices of the ith triangle
    if any(a(:,3) > max(bz))
        continue;  
    end
    %extract the three vertices
    p1 = a(1,:);  
    p2 = a(2,:);
    p3 = a(3,:);
    format compact
    area = area + 0.5 * norm(cross(p2-p1,p3-p1));  %calculate the area of the small triangle and add with previous result
end

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The above code gives me surface area = 47975.3181943477. This represent pixel, right.

How to measure the real surface area by applying caliberation factor. Please help me how to measure caliberation factor because i am new in this field.

The cone is orginally genereated having radius 78 mm and height 188.4 mm.