Do it yourself traffic?

[GPSBear]

After reading all the broadcast traffic signal problems and also after trying to get to an appointment last night with three local major through routes being dug up for gas/sewers for weeks on end and being either closed or one way...............

Anyway. Does anyone know what the traffic thing actually downloads into a GPS such that it knows to avoid it? Because if it is a special POI then could we not build a road works database like the speed camera one?

OK it won't solve the instant jam problem due to sheer weight or accident, but there are enough long term road works that it might be useful.

[swing]

No, it's not as simple as just a list of POIs, as it contains start and end locations, the type of problem, and the expected delay. Certainly some long term roadworks are included in the data, but mainly on the trunk roads.

[GPSBear]

OK so it is not a straightforward POI - But do we know how to do it?

Would be nice to do. For example every route from here ends up recalculating because I can't drive down the high street for 8 weeks! If I could only tell it that it was closed...........

[swing]

Indeed - that's an often requested additional feature - either the ability to request a reroute based on a road block, or an Avoid feature.

[wilburforce]

Actually i see no reason why a database could not be made similar to speed cameras. The problem lies with the updates.

Major long term road works ...yes
Short hold up probably wont work.

I would use them if they were available but who is going hold the list?

Nice idea. :o

[GPSBear]

We need to know *how* to get such info into the GPS first. If that can be done I doubt hosting will be that much of a problem - I might even do it myself.

[swing]

Personally, I'd prefer our efforts to be put into getting Garmin to fix the problem with the traffic modules, not coming up with a way around their problem.

Also - what will we do with the information - the units have no "avoid" option, so it would take a lot of work to avoid any roadworks, especially with most units only having 1 via point!

[GPSBear]

Well, for one thing it would be useful for folks *without* traffic receivers. Secondly the units *do* have an "avoid" option - It's triggered by whatever it gets from the traffic receiver. Hence the original question in this thread "do we know how to encode that?"

[swing]

A valid point about those without traffic.

As for having an avoid option, I'm not sure it does. The unit has the capability of working out a better route is available (based on road distance / average speed on those roads) - a few people have seen this kick in whilst driving even without the traffic module.

I think all the traffic module does is vary the average speed on particular roads, and then this "I've spotted a better route" algorithm comes into play.

I don't, for example, think it uses an actual file on the disk that we could create and pre-populate, I think it's all done in memory on the fly (although I may be wrong on this point).

[GPSBear]

Daft thought time :-)

Nuvi's have USB. You can plug them into a PC, therefore they must be USB "slave" units. (USB is not peer to peer.)

TMC units plug into the USB port, therefore they must simulate a "controller or PC" type.

Now if we hooked a USB hardware sniffer between the two it ought to be possible to find out just what the TMC sends to the GPS. Once that is figured out then a similar data stream could be generated from a PC. Of course if you are correct about it all being done in memory then we are before we start. We could ask Garmin - But I doubt they would tell us :-)

[swing]

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