
Bluetooth beacons with time-of-flight map rooms automatically - jimiasty
http://blog.estimote.com/post/154460651570/estimote-beacons-with-uwb-can-now-automatically
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jimiasty
Hi HN, this is Jakub, founder of Estimote (YC S13). We just presented during
CES Bluetooth Discover Blue event our new product: Location Beacons with
ultra-wideband (UWB) radio built-in.

Thanks to time-of-flight technology beacons know the distance between each
other and using Bluetooth mesh pass these data to cloud creating a floor plan
automatically.

On top of that indoor location apps can be created. Happy to answer any
questions here.

~~~
pizza
Time-of-flight is like knowing (dt_[1, 1] = 0,) dt_[1, 2], dt_[1, 3,], ..
dt_[2, 3], .. dt_[n, n] for all inter-beacon times, and I'm assuming bluetooth
signal travels through air in essentially constant time (doing any muxing of
bluetooth "channels", if such a thing need exist, to prevent "overlap" of
bandwidth?).

So do you have some kind of convex hull program that finds a shape of (dx = v
* dt), where any predicted dx_[1,3] >> dx_[2,3] + dx_[1,2] implies some line-
of-sight obstruction between beacon 1 and beacon 3? Especially when combined
with dB of signal strength versus mere "dx" quantity alone?

I guess I'm wondering what the typical resolution is of a floor plan, how many
beacons are necessary, and what kind of algorithm can crunch all those numbers
into a neat path-planning-type solution.

edit: I'm quite the fool this morning, having not read the post before
commenting! Nicely done. Looks like a sweet product. Hope you're able to grow
the company!

~~~
jimiasty
The time-of-flight is actually possible because of UWB radio. It's an
additional chip to Bluetooth that can estimate distance between nodes with
inch precision. Then using Bluetooth mesh these data are passed to other
beacons and to phone where automapping is performed. Once we know location of
nodes standard indoor positioning with Bluetooth beacons is performed.

Bluetooth range is aprox 100m and UWB range 70m, so that's the maximum
distance between nodes. The more nodes you have the more accurate the shape
is.

For a 1000 sqf office you would neeed probably 12-20 beacons. For a retail
store more than a 100.

