Real world testing
We tested the TMC with the latest TomTom Go 930T. For a week, we braved the hectic, attack-dog frenzy of Sydney traffic to test the system. We chose the main peak hour commuting hours (morning and evening), when traffic is often at its worst, finger's crossed that the TMC would magically tell us where the traffic problems were, and advise us a sneaky exit strategy to avoid those areas.
|The traffic service as it appears on a TomTom GPS (TomTom XL)|
For this to all work, it depends on SUNA’s data being accurate, up-to-date and better than the helicopter reporter who watches down on us with glee. All great in theory, but as we discovered - this might be expecting too much.
There's still a fair bit of leeway to be expected as this technology. Even though it was launched in Melbourne 12 months ago, its still early days in the rollout. Sydney and Brisbane have only been online for the last few months and its only natural that users may experience testing difficulties as we did.
Trial by TMC - our driving test
|Hopefully, you get to avoid this by using a traffic-ready GPS|
Our main drive took us from Sydney’s upper northern beaches, through the narrow corridors of the lower North shore and into North Sydney, where our offices are located. In between our peak hour journeys, we also glided around the one way streets of the inner city, zoomed across the gridlock provided by the Harbour Bridge, took a few detours out West and generally went looking for traffic.
The notion of being told where the traffic is in advance seems like a sci-fi dream, but after a few rounds of using the device, it became a little frustrating.
In one case, we were warned at the start of our journey that there was a 28 minute delay to be expected on our trip - and the GPS offered us a choice to reroute our journey. To see how the TMC worked, we decided not to take the change of route, but to live dangerously and drive right on into the traffic snarl.
On the TomTom 930T (and all TomTom Traffic devices for that matter), traffic areas appear as a small driving icon to the right of the screen, on a vertical axis. The traffic icon is supposed to tell you how many kms you are from the traffic hotspot, except, the closer we got to the hotspot, the less the delay became until finally the delay had disappeared off screen entirely.No traffic warnings at traffic hotspot?
Worse, once you are in the traffic hotspot - you're stuck. There are no travel warnings for the driver when you find yourself in a long bottleneck. Unfortunately, unless you were paying attention earlier while driving - you won't know how long the delay is or what type of delay it is, because the warnings came before; the traffic warnings are snapshot projections of a traffic site - they are not real-time traffic warnings inside the traffic area. It would be nice to be able to go back and read the warnings, but there is no review button or rewind to find prior warnings. Rerouting
Surprisingly, during the many times we tested it, the TMC data warned us to reroute away from lengthy delays, even though the delays failed to materialise when we arrived shortly after. Although the traffic area may have looked busy, it was hardly the massive traffic snarl that we were led to fear. The data was simply showing a 'traffic snapshot'. Either way, it didn't match up to the real driving conditions.
In fact, only a few of the traffic bottlenecks that the TMC had warned us about were actually traffic problems in real life. What might have been a 28 minute delay only moments before, had suddenly morphed into a 2 minute nuisance – how could the data change so rapidly? Another traffic example
In another case, the TMC warned us that traffic was supposed to be banked up for 3.8km in 3km distance awaiting us on our route (a 10 minute drive on the north shore). When we arrived, the extent of this delay was hardly longer than a couple hundred metres at best. If it had only happened once, we would of put it down to coincidence. But when it happened more than a few times, we grew skeptical.
Perhaps it’s a little unfair and unrealistic to expect the device to project accurate conditions at every moment. Traffic changes so quickly that by the time you get to the location, conditions may have changed.
Even so, these false positives dampened our expectations using the service. SUNA’s traffic predictions felt slightly unpredictable, though the anarchy of Sydney peak hour traffic made it feel like it was still worth having on board. Any warning is better than no warning, we decided. Delays the system missed
Perhaps more troublingly, the delays that we did experience along our route near the surrounding suburbs of North Sydney were not being picked up by the service. This may have something to do with the faulty detectors on the road that we were driving on, or a little known traffic term known as data smoothing (see next page).
As we drove the same route everyday, familiar bottlenecks that spanned long distances refused to register on screen – one of the most frustrating features we found. On a couple of occasions we decided to reroute, only to push into more traffic.
Out of curiosity, we also tried taking our Tomtom GO 930T on the bus, but without power from the car battery (via the cigarette lighter), the TMC won’t work – which is a shame, because it would be nifty to get live traffic updates on your public transport route. Just think how popular you could become with the other passengers, knowing with annoying precision why the bus was taking an hour longer than usual.(- continued on next page -)