To Define a User-Defined Motor Function
When you define a motor, use this procedure to specify a User Defined Function Type in the Profile Details tab.
1. Select User defined from the Function Type list.
2. Click to add a row.
3. To edit the expression, select it and click . The Expression Definition dialog box opens.
4. On the Expression Definition dialog box, enter an expression in the text box, or use the following options to create an expression:
Click to open the Operators dialog box and select an arithmetic operator for your expression.
Click to open the Constants dialog box and select a constant or parameter for your expression.
Click to open the Functions dialog box and select a mathematical function for your expression.
Click to open the Variables dialog box and select a previously defined measure or variable for your expression.
Click to validate your expression and open the Expression Graph dialog box.
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When you select one of the items from the Operators, Constants, Functions, or Variables dialog boxes, it appears as part of your definition in the expression entry area.
5. To specify the range for the primary variable in your expression, specify an Expression Domain. Select from the list and enter a number for an exclusive bound, or select from the list and enter a number for an inclusive bound.
a. Click to select the Specify domain check box.
b. Type a value in the box or select from the list of previous values, to set exclusive or inclusive upper and lower domain bounds.
c. Select the expression operators < or <=.
d. To make the function open-ended, specify only the lower limit of the domain for the last expression segment.
When the function consists of only one expression segment, domain is optional. The time you specify for the domain for force/torques and force motors is relative to the beginning of your analysis.
6. Click OK. The expression and domain values appear in the Expression and Domain columns in the User Defined Profile Specification area of the Profile Details tab.
7. To change an Expression or Domain value, click the value and edit it.
8. To remove one or more rows from the table, highlight the rows and click .