[Archive] Satellite real length

Message by Kouichirou Ikeda:
***I can not reply to “3D mesh model problem” thread.
***”Reply to this thread” button does not work.
***So, I have made this thread, Sorry.

Dear Julien,
Thank you for your good advice (at “3D mesh model problem” thread).
I cleared that error by changing computational area size.
And, I uploaded WINDS_simple.geo file to Common Exchange Area.
(WINDS is JAXA’s geostationary satellite)
Now, I have a next question.
WINDS has 25 meter width (from the left panel to the right panel).
I could not find the way to input the real length in SPIS yet.
So, I could not input the real width of 25 meter in SPIS.
Is there any way to input that?
Or, does 1 point of coordinate in Gmsh model correspond to 1 meter?
I’m looking forward to your reply.
Best regards, Kouichirou Ikeda

Message by julien:
Dear Ikeda,
Sorry to answer so late, quite busy these last times. First of all, and for the name of the community, thank you for your CAD file. This is a great contribution.
Now, to anwser to your question: The real size of your S/C is directly defined by the coordinates of the points used in the CAD. For example, you can find below an example of sphere of radius 1.0 (this can be changed in another value). To have a larger sphere, you can just change these coordinates. The same idea can be used to set the object not centered on the origin.
The resolution (here 0.5) is only given to define the local characteristic scale of the mesh. it must be lower than the size of the object… of course.
In SPIS-NUM, for the numerical kenel the unit is the meter. The S/C must be defined in meter.
Last point, you can also used the translate/rotate/scale capacities of Gmsh. However, in this case you must then saved your S/C as unrolled geo file. Ths problem has been solved in the last version of SPIS, which must be released soon.

// coordinate of the nodes
Point(1) = {1,0,0,0.5}
         // the format is Point(node Id) = {x, y, z, resolution}

Point(2) = {-1,0,0,0.5}

Point(3) = {0,1,0,0.5}

Point(4) = {0,-1,0,0.5}

Point(5) = {0,0,1,0.5}

Point(6) = {0,0,-1,0.5}

Point(8) = {0,0,0,0.5}

// curves to define theCircle(1) = {4,8,1}

Circle(2) = {4,8,5}

Circle(3) = {1,8,5}

Circle(4) = {4,8,2}

Circle(5) = {2,8,5}

Circle(6) = {2,8,3}

Circle(7) = {3,8,1}

Circle(8) = {6,8,3}

Circle(9) = {6,8,2}

Circle(10) = {6,8,4}

Circle(11) = {6,8,1}

Circle(12) = {3,8,5}

//line loops to define the surface of the object.
Line Loop(13) = {4,-9,10}

Ruled Surface(14) = {13}

Line Loop(15) = {-2,4,5}

Ruled Surface(16) = {15}

Line Loop(17) = {-5,6,12}

Ruled Surface(18) = {17}

Line Loop(19) = {-6,-9,8}

Ruled Surface(20) = {19}

Line Loop(21) = {-3,-1,2}

Ruled Surface(22) = {21}

Line Loop(23) = {-3,-7,12}

Ruled Surface(24) = {23}

Line Loop(25) = {-7,-8,11}

Ruled Surface(26) = {25}

Line Loop(27) = {1,-11,10}

Ruled Surface(28) = {27}