CENTER OF GRAVITY

[Anonymous]

Hi All,

I have a concrete wall with some penetrations on it. I am trying to calculate the center of gravity by using "ComputeCentroid()". 

The description of "computeCentroid" says that to calculate the center of gravity correctly, the solid should be a "homogeneous solid". I was wondering if a simple wall with some voids on it can be considered as a homogeneious solid?

Thanks,

Dave

[jeremytammik · Accepted solution]

Dear Dave,

Thank you for your query.

I believe it can.

I believe that 'homogeneous' in this case means that your concrete walls use the same density concrete throughout, no local variations in density or material or whatever.

In addition, here are some related discussions by The Building Coder:

• http://thebuildingcoder.typepad.com/blog/2012/12/solid-centroid-and-volume-calculation.html
• https://thebuildingcoder.typepad.com/blog/2015/06/dynamo-centroid-volume-calculation-migration-blitz...

But, as a true-blue programmer, you are certainly not going to trust any documentation, or another human being, are you?

Try it out for yourself in various test cases, both simple and complex, verify the statement, let us know what you found out, and check out whether we are going to trust you.

Thank you!

Best regards,

Jeremy

[Anonymous]

Hi Jeremy,

I truly appreciate your help. 

I did as you suggested and tested the code for several panels with voids, I also calculated the center of gravity for those panels manually and the result was accurate enough. In some cases, there was just 10mm discrepancy in X or Y of the COG between the 2 results. Considering that the manual calculation was more accurate, we can claim that the  ComputeCentroid method is not exactly that accurate but for engineering purposes, it provides adequate accuracy.)

Regards,

Dave

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@jeremytammik wrote:

Dear Dave,

Thank you for your query.

I believe it can.

I believe that 'homogeneous' in this case means that your concrete walls use the same density concrete throughout, no local variations in density or material or whatever.

In addition, here are some related discussions by The Building Coder:

• http://thebuildingcoder.typepad.com/blog/2012/12/solid-centroid-and-volume-calculation.html
• https://thebuildingcoder.typepad.com/blog/2015/06/dynamo-centroid-volume-calculation-migration-blitz...

But, as a true-blue programmer, you are certainly not going to trust any documentation, or another human being, are you?

Try it out for yourself in various test cases, both simple and complex, verify the statement, let us know what you found out, and check out whether we are going to trust you.

Thank you!

Best regards,

Jeremy

---

[jeremytammik]

Dear Dave,

Thank you for your confirmation and appreciation!

Very glad to hear it helped.

Best regards,

Jeremy