Any Transport Engineer here?

Hello Folks

Well I have a small question regarding some transport related issue and was wondering if we have any transport engineer on board.

I have been reading about SCATS (Sydney Coordinated Adaptive Traffic System) and its use across the world. SCATS is a traffic managment tool that works by sensing traffic data and using the data to alter signal timing at a traffic light intersection. Though SCATS was developed in Sydeny , but today more than 22000 intersections across the world are controlled by this traffic managment tool.

You may have notices that "sensing traffic data" is in bold in above paragraph. This is because my question is regarding the format of this data. I know what SCATS senses - gap between vehicles. I know how SCATS's sensors ( inductive loop detector) works. What I dont know is the format of this data. Inductive loop is an analog sensor which outputs 1 and 0. 1 represent vehicle over the loop and 0 represents no vehicle over the loop. The inductive loop outputs this information to a local controller present at an interection.

The local controller transfers "data" to the SCATS region computer. Now my question is regarding the format of this data. Is it a set of 0s and 1s directly from the loop or calculated gap for SCATS to process.

Thanks in advance

Have a look at this brochure:
https://www.traffic-tech.com/pdf/scatsbrochure.pdf

Range of communications options including leased line, fibre, broadband IP, GPRS and GSM.
Each SCATS regional computer can collect data for 4,000 system detectors.
The format of this data is most definitely digital. The local controller meassures the gaps between the vehicles and sends the data to the regional computer +/- every 30 seconds.

Thanks for the reply

So you saying a set of 1s and 0s are sent by the local controller to the SCATS regional computer? This would look like --> 000001110000011110000111.

If this is true, SCATS must first extract vehicle flow rate and lane occupancy from this digital data from the local controller and then use it for traffic control purpose.

The local controller will meassure the gaps, flow rate, idle times etc. Then it will package this data (in digital format) into communication packets that will be send through to the regional computer in intervals that is most likely decided on by the regional computer. The regional computer will analyse this data along with the other data for the area and will then update / adjust the timing rules for each local controller. It will then send this updated timing rules for each local controller through as digital communication packets to each of the respective local controllers.

The format of the communication packets will differ depending on whether it is transmitted over leased line, fibre, broadband IP, GPRS and GSM, etc.
The communication protocols used for the SCATS system are proprietary. I think the latest version is called VC5, it was designed with reliability as a primary objective. No - I don't have it.

Please take a look at this presentation for a better understanding of the SCATS system architecture:
**broken link removed**

Why cant I see "Helpful " option ?

Anyway seems like you have worked with SCATS before. I have only been reading about SCATS and never really got a chance to play around with the software.