Is my babysitter still at home?

[JDogg016]

1) Give a description of the problem
So I am trying to automatically determine whether our babysitter has left the house. I have a very decent way using IFTTT to determine when my babysitter unlocked my August lock but the web piston I designed to determine whether the babysitter left.

2) What is the expected behavior?
I would like the piston to begin tracking for the 10 minute period after everyone leaves the house but the house is still in babysitter mode. From there ANY MOTION or any CONTACT opened would keep the house in babysitter mode until someone returned.

3) What is happening/not happening?
Two things that I do not know how to address:

1. How do I start this 10 minute timer when everyone leaves; and
2. Because I am unsure of how to accomplish #1, the house will detect no motion within this 10 minute time frame and kick on the alarm.
   

4) Post a Green Snapshot of the piston
(UPLOAD YOUR IMAGE HERE)

5) Attach any logs (From ST IDE and by turning logging level to Full)
(PASTE YOUR LOGS HERE BETWEEN THE MARKS)

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If a solution is found for your question then please mark the post as the solution.

[disforw]

I have a similar interest and using the Smart Home Monitor switch I came up with what I think would be something you may want to have a look at…

Smart Child Monitor - disforw

Using the Smart Home Monitor switch I can set the system up as an advanced child monitor. If I am leaving a babysitter to watch the kids, I set it for ARMED/STAY which will send me a notification if the babysitter tries to open a door or lock. If I am leaving the kids home alone once they are sleeping I set it to ARMED/AWAY which will send a notification on any motion in the house. [download]