# Creating constraint expression using automator

**URL:** <https://forum.sensmetry.com/t/creating-constraint-expression-using-automator/250>\
**Category:** How-to Guides\
**Tags:** automator\
**Created:** [October 10, 2025, 3:47pm UTC](https://forum.sensmetry.com/t/creating-constraint-expression-using-automator/250 "2025-10-10T15:47:51Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![Rypke](https://avatars.discourse-cdn.com/v4/letter/r/b38774/32.png) [@Rypke](https://forum.sensmetry.com/u/Rypke)\
**Post date:** [October 10, 2025, 3:47pm UTC](https://forum.sensmetry.com/t/creating-constraint-expression-using-automator/250/1 "2025-10-10T15:47:51Z")

</div>

Hey,

I can’t figure out how to add assumed and required constraint to a requirement definition using automator like the screenshot below from the spec. Is there a solution available for this?

 ![image](https://canada1.discourse-cdn.com/flex008/uploads/syside/original/1X/77f215cab600a6609edff1757963b1a4cef4b40e.png)

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<div class="post-metadata">

**Author:** ![Daumantas](https://yyz2.discourse-cdn.com/flex008/user_avatar/forum.sensmetry.com/daumantas/32/19_2.png) [@Daumantas](https://forum.sensmetry.com/u/Daumantas)\
**Post date:** [October 13, 2025, 6:19am UTC](https://forum.sensmetry.com/t/creating-constraint-expression-using-automator/250/2 "2025-10-13T06:19:40Z")

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Hi @Rypke,

You will want to add `ConstraintUsages` with `RequirementConstraintMemberships`

```py
mem, assume = maximum_mass.children.append(
    syside.RequirementConstraintMembership,
    syside.ConstraintUsage
)
mem.kind = syside.RequirementConstraintMembership.Assumption

```

and `syside.RequirementConstraintMembership.Requirement` for `require constraint`.

 ![image](https://canada1.discourse-cdn.com/flex008/uploads/syside/original/1X/75d99ea3e270ca5594f4c23f144da30e37046452.png)

---

<div class="post-metadata">

**Author:** ![Rypke](https://avatars.discourse-cdn.com/v4/letter/r/b38774/32.png) [@Rypke](https://forum.sensmetry.com/u/Rypke)\
**Post date:** [October 15, 2025, 7:26am UTC](https://forum.sensmetry.com/t/creating-constraint-expression-using-automator/250/3 "2025-10-15T07:26:22Z")

</div>

Thank you. I also cannot find how to make the ConstraintUsage expression itself (so massRequired \> 0 or massActual \<= massRequired) in the documentation.

---

<div class="post-metadata">

**Author:** ![Daumantas](https://yyz2.discourse-cdn.com/flex008/user_avatar/forum.sensmetry.com/daumantas/32/19_2.png) [@Daumantas](https://forum.sensmetry.com/u/Daumantas)\
**Post date:** [October 15, 2025, 7:48am UTC](https://forum.sensmetry.com/t/creating-constraint-expression-using-automator/250/4 "2025-10-15T07:48:26Z")

</div>

Results are created through `result_expression_member` property, something like

```python
_, result = constraint.result_expression_member.set_member_element(
	syside.OperatorExpression
)
result.operator = syside.ExplicitOperator.Less
result.arguments.append(syside.FeatureReferenceExpression)[
	1
].referent_member.set_member_element(mass_required)
result.arguments.append(syside.LiteralInteger)[1].value = 0

```

 ![image](https://canada1.discourse-cdn.com/flex008/uploads/syside/original/1X/613fcdfd0fb313098d718c31ff1a6d5df16e9bf5.png)