Custom units on a drawing

[evolDiesel]

We have a situation where we would like to create a drawing in milliradians. Milliradians are a simple calculation of inverse tangent of rise over run where rise is the actual linear dimension, run is a constant we already have, and then multiply the whole thing by 1000 to get the “milli” part.

My question: Is there a way to have a print where all the dimensions are a result of a calculation [or formula] like the one I’m talking about above since 'milliradians' are not a selectable unit in SolidWorks?

Let me know if this clear enough. Maybe for now we could simply the formula to “multiply by 2”, or whatever, and ask the same question; although we will need an inverse tangent function to pull this off.

Thanks for your input guys,
Jack


Jack Lapham, CSWP
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[EEnd]

If you want to apply this to actual angular dimensions, it is possible to set up your drawing to use radians as the unit of angular measurement. However, I do not see a way to automatically get the factor of 1000.

If:
[ol][li]You are actually wanting to display linear dimensions as milliradians.[/li]
[li]Your run is constant over the entire drawing[/li]
[li]Your run is much larger than your rise[/li]
[/ol]
You could use the approximation that for small x, tan(x) is approximately x. If x=80 miliradians, atan(x) * 1000 = 79.8. If x=50 miliradians, atan(x) * 1000 = 49.96. If x=30 miliradians, atan(x) * 1000 = 29.991. If the approximation is close enough over the range of values that you have, then you can add a scale feature to the part being dimensioned (1000 / run) and the linear dimensions would then be mapped to miliradians.

Eric