Libelium Waspmote Smart Parking v2, Technical Manual

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Smart Parking node
3.7.2. Understanding I nfo and Keep-alive frames
In the regular working mode (day-mode), "Sleep" and "Keep-alive" parameters are used. So the node normally
sleeps for a speci fi c "Sleep" time then wakes-up, measures and applies the algorithm detection in order to detect
changes in the parking slot.
I f a change is detected from ’ free ’ to ’ occupied ’ or viceversa, then an " I nfo" frame is sent. I f no change occurred
during the last "Keep-alive" time, then a Keep-alive frame is sent. Besides, if a sensor error is detected, a Keep-alive
frame sending is forced in order to inform about this issue.
Example parameters used:
‚
Sleep: 7 minutes
‚
Keep-alive: 1 hour
Figure : Example I nfo and Keep-alive frames
3.7.3. Understanding night-mode
As shown in the parameters table, there are some parameters that allow the user to con fi gure the node to use 2
working modes depending on time settings: day-mode and night-mode.
The night-mode is a secondary and optional working mode that allows the user to con fi gure a di ff erent time basis
parameters in order to reduce the battery impact. So, it was developed to use it when the parking slot is expected
to have fewer changes (i.e. at night). Therefore, a di
ff erent night-mode "Sleep" setting is used.
I t is not mandatory to use the night-mode during night. This mode is thought to be used when less vehicle
movement is expected in the parking slots. Which could be during day time.
Example:
‚
Day-mode:
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Sleep: 1 minute
‚
Night-mode:
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Night-mode start hour: 21 hours (9 PM)
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