Inserting Parameters into iProperties

A common challenge Inventor's users face is the need to put model dimension values into iProperties.  For example length, width, and thickness values into the description.  Many users resort to manually entering these values.  This usually results in errors because they forgot to update a value when the model changes.  However, manually entering these values is not necessary.  It is possible to link your description or any standard or custom iProperty to a parameter value.

The first step in this process is to understand the meaning behind the Export column in the parameter dialog.

The Export column has two roles.  One is it will allow the parameter value to be derived into another part during a Derive operation.  The other role turns this value into a Custom iProperty.  I use the Export column for this purpose more frequently than for Derive operations.

Simply checking that box isn't all there is though.  Since parameters are typically entered as decimals, it may be necessary to format the value in the custom iProperty.  Also, you need to understand the formula for getting the iProperty value into another iProperty, i. e. the Description.  To illustrate how to do this, I am going to use a wall panel similar to one I would have made back in my days in the RV industry.  I have made the part as a rectangle that I extruded, then added a few cutouts.  To make creating the formula easier, I like to give my parameters meaningful names, so I name them Length, Width, and THK.  I can then check the Export column for those three parameters.

Then I want to make sure that Custom iProperty associated with these parameters are formatted the way I want.  Right-clicking in the Equation Cell for an Exported parameter will show the command to format the iProperty.  

In this dialog, I have options such as decimal or factional, precision, and unit string.  The Apply to existing comparable parameters options will also format other exported parameters the same way.  This can save a lot of time since you won't have to format each parameter individually.

Now, opening the iProperty dialog and jumping to the Custom tab, I will see the three custom iPropertiers that were created by exporting the parameters.

The formula to insert these into another iProperty isn't that difficult.  It is just a matter of starting the value with an equal symbol, to signify that you are going to be creating a formula.  Then anytime you want to insert a parameter, you enclose its name in <   > symbols.  So in my case, my Description will be =<THK> Panel, <Width> x <Length>.

This formula method will work in an iProperty and will allow you to pull from any iProperty.  Once a formula is entered, the iProperty will display the result of the formula.  If you need to edit the formula, clicking the function symbol next to the iProperty will display the formula, so you can edit it if necessary.

Here is a video demonstrating how to accomplish this.