[HH] cheap navigation unit

[Tom Metro]

Kurt L Keville wrote:
> ...how the Prius seemed to know where you were going after we entered
> the Ted Williams tunnel. I assume it had a pretty good INU built-in...

Inertial Navigation Unit?

So you are saying it kept you on the virtual road despite having lost
the GPS signal?


> ...and had access to the speedometer...

Any evidence to suggest it didn't just average the speed observed in the
moments before entering the tunnel and extrapolate from that?

The interesting test would be to drive into the tunnel and stop and see
if your virtual position keeps moving.

In all probability the GPS system is completely isolated from the car's
main computer that has access to the speedometer data, but that's just
speculation.


> is there a free Skyhook-like system model?

Yes, supposedly Google has one. It may only be free for Android apps.


> ... I was looking at projects like
> http://rvsn.csail.mit.edu/location/

That talks about using Wi-Fi triangulation for indoor navigation.

This is the same stuff they're doing the the latest Google Maps app,
right? Where you can navigate inside malls and stores.

 -Tom