Parameters and units

[jeffescott]

I wish to calculate the moment of inertia (beam calcs).  The units are mm^4.

Of course in the drop down to add a parameter there are no units for mm^4.

Furthermore the only area units are acre or circular mil.  (not much use especially in a metric set up)

So there must be a work around or something to make this work. do I have to divide by mm^3 or what.

Also since I am working in the sheet metal environment. The width and depth are contained in the sheet metal rules.  As I change the width and depth can I pull the values from the rule.  Maybe I should just get the length from the sheet metal, and pull the width from the solid ???

Oh and while we are at it... I have used a pipe to calculate the length of my spring it comes to 148.767mm

I have also used sheet metal to calculate the length of my spring it comes to 148.178.  This might use some bending rules to calculate the length, I would have though you would need a slightly longer piece to start bending the form no a shorter piece?

[g-andresen]

Hi,

If you scroll through the units in the parameter list, you will see that there is neither “Moment of Inertia” nor any form of mm^xx.

günther

[jeffescott]

Yes true, so you mean to say I can't do it parametrically???

I seemed to have lucked into calculating the moment of inertia correctly. by selecting unitless.  Not sure why but there it is???

See attached file modify>change parameters>MInertia

[jeffescott]

K so I can do what I want but this seems really really stupid for a design program in 2024.

I create a user parameter with no units.

I then enter a formula which uses Model parameters (result would be in mm4); i divide by the correct units(mm4) to make it dimensionless.

I create a user parameter with no units.

I then enter a another formula which uses model parameters (result would in mm3); i divide by the correct units (mm3) to make it dimensionless.

I create a user parameter with the units I want (mm); i enter the unitless parameter; I multiply by the unit I want (mm).

Bingo I have what I want.

Please tell me there is an easier way????