Guards for State Transitions

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Guards for State Transitions

Post by pfp.meijers »

Does anyone know of a construct to add guards (expressions on other variables) to state transitions?
Can this be done via the standard defined types or would this require to model subtypes?

E.g. a state transition with a certain cause (HasCause reference) should only be effetuated if a variable of the state machine has a certain value.
I could imagine doing this via a new reference subtype (HasGuard) in combination with a Guard property (Equals) or so. But don't know if this is the intended way to model things. So much flexibility in address space it looks like.

Note that in principle the value range of this variable to be guarded represents a collection of different states. But I do not want to expand/include all of them, in order to keep the state model simple.

Thanks in advance for any feedback.

Grt, Patrick

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Re: Guards for State Transitions

Post by Support Team »

Hi Patrick,

A transition can point to a Variable as cause of the transition (HasCause). But there is no standard way yet to express the condition (e.g. a specific value) that triggers the transition. The behaviour is only well defined for Methods (triggers transition if executed successfully).

Best Regards,
Unified Automation Support Team

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