NGEN Traffic Signal Controller Personality Configuration Software
The traffic industry in Australia has had a long history of developing systems that have over time become more complex and feature rich.
The first traffic signal controllers were all based on relays and timers and cam driven mechanisms to control which traffic signals (lights) turned on at a given time.
Add to that, detection systems came into being, and the number of vehicles provided some statistical information that could be used to “detect” the presence of a vehicle and also a count of how many vehicle passed over a given detector.
Suddenly, the time a controller spent in a given phase could be altered based on all of those inputs (not forgetting the poor old pedestrian of course) and provide a more responsive system.
A typical situation would be a vehicle waiting on a side street waiting to get onto a major arterial road at night. Depending on when the vehicle got to the intersection they could wait a long time before the controller would allow the side street vehicle to move.
With vehicle detectors, the controller is now aware of the waiting vehicle on the side street and if the major arterial road has light amount of traffic or none (because it is late at night) then it can shorten the phases on the major arterial road and give a green light to the side street vehicle.
These sorts of features have slowly been added to the configuration of a traffic signal controller.
When traffic signal controllers moved to the microprocessor age, such information was stored in a DIP packaged EPROM of several KB.
The latest version of the “PROM” as it is commonly referred to by traffic engineers and technicians has evolved to a PCMCIA or “Cardbus” card that is commonly found in laptops.
If you write personalities or wish to you will need some Cardbus Drivers to install on the windows platform before you can do so.
A program called NGEN and various predecessors of it are used to “create” or “generate” a file in an “sft” format – a motorola format. This file is loaded onto a PCMCIA card (Type I – single slot) and then inserted into the Traffic Signal Controller’s Cardbus slot.
Prior to “running” the personality, the creator of the personality can use a test Controller to see if it runs as designed or use an ATC “Workstation” which simulates the Signal loads (traffic lights), pedestrian inputs and vehicle detections and wait state outputs.
In either case, a traffic engineer will ALWAYS test the personality to ensure its phasing operation is in accordance with the intersection design it was intended for.
To accompany the actual configuration, the traffic engineer will always create a written file commonly called the “Operational Sheet” or more commonly known as the “OP-Sheet”.
This document contains text and phasing diagrams that show the expected movements of each phase as well as mapping all vehicle detector channels and pedestrian input channels.
These channels mapping need to be in accordance with how the site wiring for that equipment was installed.
The Traffic Signal Controller installer will use this OpSheet to connect all the field wiring present at the bottom of the pit to connect to the various items in a Traffic Signal Controller – Signals (lights), vehicle detectors, pedestrian push button inputs, wait outputs and communications link back to SCATS if this controller is part of adaptive coordination.
Each traffic authority generate their own OpSheet based on the information each needs to record to implement a Traffic Signal Controller.
For information on how to generate a “Personality” for a Traffic Signal Controller click on the Personality Generation Training Course for details.
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