Road Speeds

 

Hi All,

I'm the proud owner of a nuvi 680 (my first GPS) and the thing is awesome! I have a question about functionality:

Is there a way to download the speed limits on the road that I'm on? It would be interesting to be alerted if I'm driving about a set threshold for the speed on that road.

If this isn't possible no worries... just curious!

Stevo

Possible but impractical

It's possible, but I think it would take a huge amount of work - so much that it would be impractical. I don't think speed limit data is included in the maps delivered with the unit (anyone else here disagree?). I think the only way to do this would be to set up a POI database with "speed cameras" on every road that you drive indicating the speed limit and have POIs (points of interest) about every 1500 feet. This would be a ridiculously huge file and would require tons of memory. My guess is eventually the map makers will include this data and Garmin can get another $500 to $1000 out of you for a new unit with this improved feature wink

Anyway, welcome to the world of GPS - it's amazing technology and they seem to think of something new every year.

Thanks for the feedback. I

Thanks for the feedback. I haven't installed any POIs just yet, but will check out what's available here and get installing!

Well, actually...

I believe that Navteq does actually include the speed limits for the roads in its database. When my C550 calculates the arrival time, it's fairly accurate when I pretty much drive at the speed limit and make no stops. The GPS does of course continually recalculate the ETA, but I'm basing my assertion on the initial calculated ETA compared to actual.

That being said, I suppose the software gurus could take a average speed of say 45 MPH as a starting point.

As my high school math teacher used to say, "You can calcu now or you can calculator." smile

It's all in the formula of the routing engine

Each road is given a classification in the routing engine that I understand includes the type of road (interstate vs US highway vs state road vs county road...) and speed limits, and average speeds one could expect to do over a route in the magic they use to calculate a route.

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*Keith* MacBook Pro *wifi iPad(2012) w/BadElf GPS & iPhone6 + Navigon*