traction using math expressions

[yanincha]

Hi, could someone tell me how to define the traction load with a mathematical expression, or point me to some examples?
Currently I am trying to use a SurfaceData,

<SurfaceData name="traction_force" data_type="vec3" generator="math" surface="all_face">
<math>-1000*X</math> <math>-1000*X</math> <math>0</math>
</SurfaceData>

but febio keeps telling me `invalid value for attribute "generator"`. Also I am not sure how to define a vector math expression.

Thanks in advance.

Jianfeng

[yanincha]

I checked the source code, it looks like generator "math" only supports scalar data, right?

[maas]

Hi,

I fixed the issue and the math generator will now also work for vec3 variables. If you reach out to me via email (steve dot maas at utah dot edu) I can give you a new executable.

However, I do want to point out that you don't need a SurfaceData section for prescribing the traction via a math expression. For instance, the following should work to:

		<surface_load type="traction" surface="SurfaceTraction1">
			<scale lc="1">1</scale>
			<traction type="math">X,0,0</traction>
		</surface_load>

Perhaps give that a try first and let me know if that worked for you.

Cheers,

Steve