Generic Presence Detection

If I understand your question, that is exactly what the DP does.

As written you can have N sensors. Each sensor is a member of Presence_Sensors. If any one of those sensors a ON then Presence_Sensors becomes ON and the Rule sets Presence to ON.

Only if all the sensors are OFF will Presence_Sensors become OFF and a timer will be set. When the timer expires Presence will be set to OFF. If any one sensor returns to ON before the timer expires, the timer is cancelled and Presence remains ON.

So Presence will only go to OFF five minutes after ALL the presence sensors go to OFF.

So if you have two sensors of mixed reliability, as long as one of them is reporting ON then Presence will remain ON.

Is this the behavior you are asking about or am I misunderstanding the question?

If you want to know who is actually on site, not just that someone is on site, then you can create a Group for each person and put the Items representing each person into that Group. Define the Group the same as Presence_Sensors and put the person’s Group in the Presence_Sensors Group.

The Rule will continue to work as is or you can expand it by using Design Pattern: Associated Items, giving each person their own proxy Item (e.g. Branden_Presence), and implementing a flapping timer for each person.