Just this week, SM Mall of Asia started installing parking monitors on its multi-level parking section. The 3rd floor parking level is still closed for the renovation and i took pictures of the finished job on the 4th floor.
The IR monitors hangs on the ceiling supported by PVC pipes that crawls all over the entire parking section. See photos I took earlier:
There are two nodes — one for the IR beam that fires right in the middle of each parking slot and another one at the rear end where a bulb lights green if the slot is empty and red if taken.
The red and green signal lights helps a driver easily identify which parking slots are available. My guess is that the monitors also report to a central system to map the parking floor and manage parking spaces. It might send reports to the security office as well as the toll gates below on the running capacity of each level.
Just an update regarding the Parking Guidance System installed at SM Malls. You may get in touch with me at 0922******* or email fm****@gmail.com. Thank you very much.