Vector expression in runtime function?

I am trying to simplify some messy equations by using runtime functions. I have a function for projecting the velocity vector of a marker into the plane of a reference unit vector that I calculate and save at some previous point in the simulation.

runtime_function create &

runtime_function_name = FUN_projvelocity &

text_of_expression = "(UV(VXYZ(M1) - ([UVNX, UVNY, UVNZ] * VXYZ(M1) * [UVNX, UVNY, UVNZ])))" &

argument_names = "M1", "UVNX", "UVNY", "UVNZ"

Unfortunately when I try to import this command I get the following error:

ERROR: The function expression indicated contains at least one error.

ERROR: A value of type vector cannot be used in this context.

ERROR:

ERROR: Function text : "(UV(VXYZ(M1) - ([UVNX[[,]] UVNY, UVNZ] * VXYZ(M1) * [UVNX, UVNY, UVNZ])))"

ERROR: (The element at or immediately after the error is

ERROR: enclosed in double brackets '[[' and ']]'.)

Is there any way to make a runtime function support vectors? I've also tried passing [UVNX, UVNY, UVNZ] as a single argument and it still gets mad at me.

0 Martin Kieltsch over 2 years ago

ADAMS is a bit picky on brackets , be it () or () or {} .

According to the help [] was the right choice for a vector of single components.

I admit being too lazy to understand what you're trying to accomplish, but the other possible issue may be the operators and supported in/output types.

* is for scalar product, % for cross product.

+/- can be applied to both scalars and vectors, but trying a (scalar - vector) will eventually fail.

What I see is a vector*vector*vector which seems a bit odd as ADAMS would have to guess which vector to multiply first into a scalar and then multiply that number with the remaining vector. Maybe some additional () around parts of your equation will help ?
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