
We're making an open-source $30 GPS/mesh radio, would like advice - punkgeek
https://www.meshtastic.org/
======
gardners
Howdy, as the founder of the Serval Mesh adhoc networking protocols and
hardware, what I would look for in a new radio is: 1\. True packet radio mode,
that doesn't hide the radioness of the link etc, but lets the programmer use
it's strengths. 2\. UART link, ideally using 3DR/RFD900 compatible connector
(then we can include it directly in our existing systems, and so can others).
3\. Field-flashable, but with robust protections on the boot loader, as it is
not uncommon for a radio to be on the boot serial interface, on hardware that
has only one serial port. 4\. Support 434, 868 and 905-935MHz ISM bands. 5\.
Use advanced interference tolerant wave-forms, like Chirped Spread Spectrum or
even something better. 6\. Fully open chipset/firmware design, so that it can
be truted. Anyway, poke me at paul@servalproject.org if you would like to talk
further about it. Paul.

~~~
drumttocs8
Upvoted for the deep knowledge shared here- but as a consumer, I don't know
enough to care anything about any of that. I think a mesh radio that keeps us
all together on a hike, festival, or emergency situation sounds pretty cool,
and being open and extensible makes it even better.

~~~
bloopernova
As a fellow consumer who doesn't have the knowledge to contribute to this
space, I really wish I could offer something to help out with these efforts.

The idea of a secondary low bandwidth Internet being robust to interference
from goverment and disasters? That stuff is true cyberpunk to me.

------
punkgeek
Hi ya'll, so we've spent a few weeks making device software and an android app
to convert a $30 chinese gps/radio into a long range mesh radio for hikers. It
is working fairly well now (though still an alpha) and we'd love more people
to try it and/or have fun coding on it.

We got about 30 users (and some devs from this hackaday article) but we'd love
more users and devs to join this happy-happy project:

[https://hackaday.com/2020/02/26/lora-mesh-network-with-
off-t...](https://hackaday.com/2020/02/26/lora-mesh-network-with-off-the-
shelf-hardware/)

I'm happy to respond to any questions or comments...

~~~
jkoberg
What frequency band are you using? ISM is the only one that permits store-and-
forward / automatic operation, as the gotenna people found.

You say a few miles per node - I am having trouble seeing how that's possible
without elevating all the nodes

~~~
superkuh
He's gotta be assuming the nodes have clear line of sight and fresnel zone.
The maximum distance for the link budget in a perfect situation. In practice
it probably cuts off at the nearest rise in the ground or depression.

But they're still cool and I still want some for non-hiking applications. With
the very low power idle and low cost they could be set up with solar panels in
the tops of trees or in similar high height above terrain positions.

~~~
generatorguy
915 MHz goes a lot farther than 2.4 GHz.

At very low bit rates you need very little SNR.

There is probably very low noise out in hiking environments.

Yes, attenuation due to terrain is going to be a killer, but my experience
with non line of sight 900 MHz links blasting through trees leads me to
believe it would be workable for low bit rate data between a series of hikers
along the same trail.

It is sending only location and text messages so intermittent link status or
re-tries due to temporarily terrain/foliage obstructions will not cause
degradation in service that you would experience trying to watch netflix over
this mesh.

~~~
superkuh
You're wrong. It's a mistake to treat terrain and foliage as the same thing. I
have extensive experience with 3 completely different, narrowband and
wideband, 902-928 MHz radio data systems as well as just playing around in the
range with my software defined radios (hackrf, rtlsdr, etc).

902-928 has almost no advantage over 2.4 GHz when it comes to line of sight
issues with terrain. In fact, it's more problematic due to the increased size
of the fresnel zone. Sure, it does better through trees but a slight rise of
ground is just as much of a problem for 915 and 2400. The freq here isn't
helping much. It's the chirp and LORA modulation helping the link budget. But
no line of sight is no line of sight.

~~~
bigiain
This stack overflow question has some nice pictures of the LoRa "chirps". They
use rising/falling frequency modulation to allow operation at startlingly low
signal to noise ratios.

(Also, the hardware they're using is fairly generic, and pretty much all the
vendors selling them offer them in 915/920MHz and also 868MHz and 433MHz
variants. I've seen claims of over 10km range with 433MHz LoRa gear without
special antennas or clear line-of-sight...)

~~~
dfox
LoRa has very peculiar modulation scheme that in the end is not CDMA-ish
spread spectrum but an interesting way how to extend straight FSK into spread
spectrum modulation with respectable processing gain and interference
rejection.

~~~
bigiain
I recall reading that part of the design was so that not only was it good at
rejecting interference, but that it also caused little interference to other
users of the spectrum.

If someone else's ISM radio is using a specific frequency (perhaps with CDMA
or TDMA), a "chirp" that's spears over about a hundred kHz and -20db or so
down in the noise is unlikely to bother them, but is quite useable/reliable
for the LORA gear to detect.

------
atourgates
Really cool.

Seems like an open-source mashup of something like Lynq
[https://lynqme.com/](https://lynqme.com/) \- and Gotenna
[https://gotennamesh.com/](https://gotennamesh.com/)

I've never liked Gotenna's requirement to be paired with a cellphone for
tracking, so I've been watching Lynq's development for a while. But, I'd much
rather have an open-source solution than one that depends on the fortunes and
whims of a single compnay. Particularly if there was easy-to-use commercial
hardware available with the open source software.

The other downside of Lynq is that it doesn't use mesh networking, e.g., every
Lynq unit can only communicate with other units it can connect to directly.
That means if you have a group of 3 people all in a line, separated by
3-miles, only the person in the middle will be able to find the location of
the entire group, and the people at the ends of the line would be invisible to
each other.

Anyway - all that to say - I'm super-excited for your project and wish you all
the best.

~~~
punkgeek
yes, that's what we thought also. Also, the phone is optional for our case
(though you need it for sending texts - if you don't have one the display
still shows rxed texts and headings/distance to members of the channel)

~~~
myself248
In my case, only the Heltec boards were easily available, and they lack the
GPS that's in the TTgo boards. So I hope there's a way for the phone's GPS to
participate!

(Or, since the esp32 has bluetooth, recognize a bluetooth GPS puck? That's
extra work and they're quite rare, so maybe nah.)

Otherwise I'm totally fine soldering another GPS onto some random GPIO pins, I
have a whole bag of those. I'm just not sure what it would take to get it
recognized.

~~~
punkgeek
also, adding support to dynamically probe for a GPS attached to GPIOs would be
very straightforward (almost identical to the tbeam case). If you're
interested in this ping us on the devchat and someone will help talk you
through it.

------
rapjr9
Note that there are limits to how large a mesh network can scale, it's likely
to start running into problems with several hundred users. You can scale
larger by limiting data to short text messages, but you'll probably never be
able to handle more than 10,000 users, unless you can find a way to create
high bandwidth backbone links between clusters of users. There has been a lot
of research on this in the wireless sensor network research community and in
the WiFi mesh network research community also. A concert going crowd could
easily cause a mesh network to become un-useably slow if everyone was trying
to use it at the same time.

~~~
keithwinstein
That's true in practice with current radios, but it was a beautiful discovery
in 2006 that it's not true in theory! In a world where radios are perfect and
nodes cooperate to do decentralized beamforming, the capacity-per-node of a
random mesh network scales as the number of nodes increases. See Ozgur,
Leveque, and Tse, "Hierarchical Cooperation Achieves Optimal Capacity Scaling
in Ad Hoc Networks," IEEE Trans. Info. Theory (2007)
([https://arxiv.org/abs/cs/0611070](https://arxiv.org/abs/cs/0611070)).

(Also worth reading: Tim Shepard's Ph.D. dissertation from 1995
([http://groups.csail.mit.edu/ana/Publications/PubPDFs/Timothy...](http://groups.csail.mit.edu/ana/Publications/PubPDFs/Timothy.Shepard.Thesis.1995.pdf)),
which predates a lot of the "information theory" interest in this subject.)

~~~
rapjr9
Interesting. I wonder how well it would work in practice though. They assume
uniform randomly distributed nodes, whereas people don't tend to distribute
themselves randomly. They don't address practical concerns either, like how
narrow the MIMO beamwidths need to be and how easy that is to achieve. Still a
nice theoretical result.

~~~
foobarian
This seems like it requires point-to-point communication; and with accurate
MIMO configuration my intuition for the endpoints is that it's like they are
communicating with laser-like narrow beams but in RF. But AFAIK multihop
communication is still stuck at sqrt(n) scaling, i.e. not viable.

This is all pretty theoretical though, for a small number of nodes like up to
100 it should work pretty well like in the OP application.

------
PVHSAlex
15 year old High School sophomore noob here. We (crazily) are attempting to
put up a CubeSat (shameless plug www.seakingspace.com). Using the Lora SX1268
433Mhz we tested the Semtech transceiver across the Catalina channel. 25+
Miles SF factors 7,9,11 at 125 BW. Worked great. We did a link budget and
should work over 500KM line of sight no prob. The SX126X is the new improved
version of the Lora chip. Im sure a verion with it will come out shortly.

~~~
airbreather
LoRaWAN® distance world record broken. 766 km (476 miles) using 25mW
transmission power. After almost 2 years, the world record of 702 km (436
miles) has been broken.Aug 14, 2019

25mW, imagine what you could do with 1/2 a watt.

------
alexisread
Not an expert by any means, but I'd suggest looking at the Dash7 protocol/
firmware as a reference for the mesh, security and positioning. It's been
around a while and seems robust.

Open source, royalty free, low power, high range (several km even in urban
areas), medium bandwidth, runs on several lora boards.

[https://dash7-alliance.org/](https://dash7-alliance.org/)

~~~
punkgeek
ooh. That is great advice! We used the RadioHead mesh solution but it is super
non optimal for us and we plan to switch. I'll definitely do some reading on
DASH7.

~~~
alexisread
Firmware available at:
[https://github.com/jpnorair/OpenTag](https://github.com/jpnorair/OpenTag)

------
kpierce
Maybe resubmit this post so the link works. I would love this for music
festivals. They have some solutions but they are hundreds of dollars. If
people in the group could put this on a backpack it would be a game-changer.
Music festivals also have a big problem with internet access. If they could
put host a few powerful repeaters in the middle with electrical and have 5% of
attendees (staff) with these they could probably cover the entire place. Send
out lineup changes or emergency notices.

~~~
Fnoord
Solutions of hundreds of dollars? For what exactly?

Reminds me of the movie Hackers where they used buzzers. And why not? The only
thing you gotta do is use pre-planned keywords/acronyms.

I went to several (music) festivals, big ones between 2002 till 2004 with a
few smaller gigs later until 2009 or so. Back then we just used SMS or phone
call. I didn't even always have a plan during the mentioned years. Especially
outside the country (and NL is small) it was always a surprise to get the next
phone bill (one time I paid something like 30 EUR per megabyte, in Serbia).
Within the EU, these work with your normal plan nowadays.

I don't know how it is nowadays, but back then on large festivals providers
would put up extra (mobile) GSM antennas at the location. I assume they still
do that. I can imagine there's a lot of smartphones up in the air to record
the magical moment (and ruin it for the people behind you). That alone is a
reason why I wouldn't wanna go.

A dumbphone seems still clever if you go outside the country. A rugged one
goes for say 30-50 EUR or so. It won't contain or give access to your whole
life if it gets confiscated, no social media means you can focus on your stay,
and you can still contact authorities or friends if required. Just make sure
you add the personal information of those you need to contact (should be on
your SIM, though possibly that's too much info as well). Oh, and the screen
won't break or get damaged (if it does /care), and who cares if your dumbphone
gets stolen. I suppose people generally take the risk, but I got burned once
(got a digital camera as birthday present worth ~300 EUR in 2004 and it got
stolen after I had it for less than a week). You can always give it away or
sell it afterwards (like a real burner) or reuse it for the next journey.

Now, back when I went to music festivals, you'd sortof stay together cause you
could find each other but it was a bit annoying. If you could automate it,
like you can give your position with WhatsApp, then that'd be great. However,
with WhatsApp you decide who can access your location, while with this
solution its available to all. That might not be what you want.

Other sports like hiking, skiing I can imagine to use this technology. Even
people who live "In The Wild" could meet up with other total strangers, if
that's your thing. I mean imagine using this in some huge forest in Canada, or
on Greenland where you suddenly notice another life form.

~~~
dfox
You have to look at the issue from the organizer PoV and not as the event
goer. You need to have some kind of reliable communication channels for the
staff. The result of 10 years of experience of trying to cause that is for me
that analog UHF radios work, wired VoIP phones work and just using whatever
smartphones the staff works and combination of these three technologies gives
you the SLA level you need. DECT is meaningful solution of the same problem,
but the handsets are expensive and even more so if you want some broadcast/PTT
capability and ideas like “well, we have bunch of Nokia S60 handsets that
should in theory support wifi as LTE/CAE radio layer” is pure nerding-out that
does not solve any kind of real issue and instead creates new ones

~~~
Fnoord
That does make sense. I did not see it from the organizer PoV indeed.

------
whalesalad
Looks like you have already written a lot of low-level code for your device
already ([https://github.com/meshtastic/Meshtastic-
esp32](https://github.com/meshtastic/Meshtastic-esp32)) but have y'all
considered taking a look at the Nerves project ([https://nerves-
project.org](https://nerves-project.org))?

You might uncover some really cool stuff in the Erlang/Elixir ecosystem for
doing mesh communications.

~~~
punkgeek
Thanks! alas, I think that is a bit to big for what we have to work with in
our ESP32s. We started our sw design based on what off the shelf hardware we
could find and worked from that.

------
zumzumzum
How is it offering 'private' communications on the 33cm band? Does this band
even offer good performance in hilly or mountainous terrain? These would be
short range line of sight only type devices, correct? I'm still fairly new to
amateur radio so I could be off. I don't see the advantage of this over
something like APRS on 2M, with the exception that you don't need a license.

~~~
punkgeek
encryption is allowed for low duty cycle digital usage on that band.

I'm also a ham and really into APRS. But not requiring a license is a big
plus, also the way these chirping radios achieve their long range with a super
high noise floor so the battery life is amazing. i.e. a TTGO TBEAM will run
for about eight days on (including the GPS/radio and CPU). And $30 for that
board.

~~~
threeio
I was going to suggest that you look into some of the patents that were the
basis for the old Ricochet Networks stuff as its the basis for most of the
smartgrid meter tech, but apparently many of them are more recent than I
expected and still under the 20 year mark... also might want to post it to
/r/amateurradio for feedback... 73 om!

------
pdoege
I worked on a similar project for Motorola and it had limited commercial
success.

Very dense topologies need to aggressively handle broadcast storms such as ARP
storms. Very fragmented topologies need to handle delay tolerant networking.

In any event, search for "Mobile Ad-hoc Networks" will show work that has been
done previously.

~~~
punkgeek
thanks! yes, we are very delay tolerant and a typical text message (or flooded
location update) takes a few seconds to get across our likely max # of hops
(which is only three, due to our u[https://github.com/meshtastic/Meshtastic-
esp32/blob/master/d...](https://github.com/meshtastic/Meshtastic-
esp32/blob/master/docs/software/mesh-alg.mdsecase))

We initially used the RadioHead mesh router (which seems to be a variant of
DSR), but we are switching to something else soon. Misc notes here:
[https://github.com/meshtastic/Meshtastic-
esp32/blob/master/d...](https://github.com/meshtastic/Meshtastic-
esp32/blob/master/docs/software/mesh-alg.md)

------
exabrial
XBee it's already at an $30 and $15 price point, I think to 'disrupt' you
would need to be profitable at a -10x price point. This is my opinion. I'm
usually wrong. But you asked.

~~~
punkgeek
Thank you. This is a full circuitboard with GPS+battery+lora+CPU+oled screen
for $30. So I'm not trying to compete with a $15 radio devboard that someone
has to solder into their project, but more something that 'just works'. And
open source, for fun, so not selling it at all ;-)

~~~
airbreather
Maybe you could persuade M5Stack to do a version of hardware that suits.

Looks like maybe they do already for $40 if you combine a base and LORA unit -

[https://m5stack.com/collections/m5-core](https://m5stack.com/collections/m5-core)

[https://m5stack.com/collections/m5-module](https://m5stack.com/collections/m5-module)

------
beering
Not sure if this is "good" advice, but this would make for a very appealing
kickstarter: cool gadget with very useful functionality for popular activities
(music festivals, hiking, skiing) that could even help in an emergency. It
hits a lot of the right notes.

Possible that when you're further along you can have a kickstarter for a
commercial version that's officially created by the open-source project. The
more (mutually compatible) devices out there, the better the mesh, right?

~~~
punkgeek
There are already a couple of companies doing similar kickstarters I think.
But we want this to be a non profit open source project for fun.

We are using a GPL license, but if someone wants to eventually sell devices
(as long as they obey the GPL) with our code we think that's great.

~~~
davidzweig
The ESP32 draws quite a lot of current when running BLE (without Wifi), unless
that's been fixed recently. IIRC, the TTGO boards have poor low-power design
that will kill the 18650 battery in a few days, no matter what you do, that
could perhaps be fixed with a small modification though.

I have a hardware design that might be an interesting starting point. It's
based around nrf52 (Cortex M4F with BLE and nice SDK), 400mah battery,
microphone, speaker, 3*4 RGB LED matrix, gyro/accelerometer, NFC. Very small
device, 35mm across. Can extend the top of the PCB, add a small OLED screen
and a LORA radio. Hitting $30 price point shouldn't be a problem. Email in
profile :-)

[https://photos.app.goo.gl/qUyrRYDrtu2SHsHR9](https://photos.app.goo.gl/qUyrRYDrtu2SHsHR9)

------
leggomylibro
Gotta love ESP32s, huh? It's great to see more affordable "commodity-style"
boards with some extra radios built in.

This looks like a very cool project - I might pick up a few of those 'T-beam'
boards and see if some people want to try taking a hike with them. Thanks for
sharing!

~~~
punkgeek
no worries. if (when ;-)) you encounter problems just post on our gitter
channel.

------
komcinity
That’s an awesome project. I was interested in LoRa for the same reason. I’m
an iOS dev and paraglider myself so I can help you with the iOS app. Let’s
chat

~~~
punkgeek
Oh would love to! Would you mind posting on our devchat and we can talk more?
[https://gitter.im/Meshtastic/community](https://gitter.im/Meshtastic/community)

------
Uhrheber
I can see why you're using these boards, but the ESP32 is an incredibly power
hungry device. For battery/solar power it's not the best choice.

For devices in the field I'd use one of the many available low power ARM
controllers.

~~~
punkgeek
we are careful to keep the esp clock-gated almost all the time (esp calls this
light-sleep), in that mode the power draw of the ESP is on 1.5mA. When the
radio (or button press) receives a packet it wakes the main CPU, which then
services everything (turning on bluetooth as needed) and then goes back to
sleep. If you are curious for more details we have a power consumptions
spreadsheet in our docs.

------
ChrisMarshallNY
I’m interested, but we’ll see how it goes. This is a non-trivial endeavor.

I’ve been trying to write an open-source Apple driver for goTenna units, and
have been unable to get them to help me out by providing their BLE spec.

That’s a shame, because I write _really nice_ SDKs. Even if my driver was open
and free, it would provide significant brand reinforcement. Win-win.

I believe that this tech is important, as it can provide service in disasters.
I’m also big on open-source.

But I cut my teeth on RF stuff, and know that it’s a real black art. Software
can get complicated, but is child’s play, compared to RF tech.

You have your work cut out for you.

~~~
punkgeek
The current alpha works pretty well. (I'm sort of retired now, but my old job
included writing software for these sorts of radios).

If you'd like to play with this project we'd love your help (and we have a
documented ble api).

Here's an issue where various iOS types are ideating on possibly making an iOS
app: [https://github.com/meshtastic/Meshtastic-
esp32/issues/14](https://github.com/meshtastic/Meshtastic-esp32/issues/14)

~~~
ChrisMarshallNY
I'll probably look at it in a few days.

I'm actually in the middle of creating a Web-based instruction series on
writing Core Bluetooth SDKs for Apple platforms (not just iOS).

Once I get that done, I may look at adapting this project:

[https://github.com/RiftValleySoftware/RVS_GTDriver](https://github.com/RiftValleySoftware/RVS_GTDriver)

For it. It started as a goTenna project, but they never got around to helping
me out, so I gave up on them, and made it an OBD driver.

The infrastructure is still there for all kinds of stuff, so I could probably
do something.

BTW: If that works out, it would be an SDK that would afford ALL Apple
platforms; including Watch and TV.

------
masukomi
The idea of these radio mesh network things is great. The reality is terrible
because radio waves need line of sight unless you've got a repeater. This is
completely impractical when hiking, or in a city filled with buildings. They
end up with crazy short range between devices and you need an implausibly long
string of them to get from a person off the grid to a mesh point on the grid.
The only exception to this being someone high on a hill with no bumpy bits of
other hills between them and whoever has the other mesh point that happens to
be on-grid.

Gotenna couldn't make this work with all their $$ because of the simple
physics of radio waves. Yes they sell devices that technically do what they
claim, they just fall flat on their faces when they encounter hills, or
buildings... or anything that isn't flat.

I think if you want to make something that actually works, you should drop the
"consumer" and make having a ham radio license a requirement. Then use the GPS
to find the closest public repeater. Their locations are pretty well mapped at
this point.

Use the most appropriate of the many ham radio digital packet systems for
whatever wavelength you're broadcasting on and choose the appropriate part of
the spectrum that is designated for digital packet use.

Also be a good radio citizen and try other frequencies if the current one is
in use.

I understand that the ham license is pretty much a deal breaker for adoption
BUT it's what's required to use the decent frequencies and access to
repeaters. As this seems to be an open source kind of project and not a "hey
lets sell bajillions" kinda thing, that seems like a plausible option.

~~~
sliken
Dunno, I think one of the biggest weakness of various ham related technologies
(and yes I have my general) is the assumption that everyone is online all the
time. Trying to communicate with a few dozen people is very inefficient with
amateur radio in general. It's usually voice, usually assumes everyone is
doing nothing but listening, is listening continuously and has perfect
reception. God forbid someone is driving, hiking aggressive terrain, or a
group of 10 people is online only 60% of the time each.

Most of the cheap ham stuff assumes a perfect repeater already to do the heavy
lifting, which is nice when you have it, but very frustrating when you don't.

I do wish that ham or consumer devices supported digital modes, peer to peer,
store and forward, push, pull, query, etc. Js8call supports this, so you can
do things like ask when someone was last seen, leave messages on 3rd parties,
ask 3rd parties to forward, etc. So even if each radio is online part of the
time, and parties that want to talk can not directly hear each other things
work just fine. It's amazing to even think about, communicating several
magnitudes below the noise floor, power levels so low that hams are proud when
they get less than 1 watt per 1000 miles!

Imagine standing on the west cost of the USA, shining a 5 watt flashlight at
the sky, having it bounce off the sky, to land, and again into the sky, and
again to the last to someone 1000s of miles away... and they can decode your
signal. Amazing stuff.

I do wonder what the smallest package you could fit a 1 watt bluetooth
connected HF radio in to enable any phone to talk js8call.

------
ourlordcaffeine
I guess my only advice is make sure the software keeps to the duty cycle
limits of the license free band. And note that different countries may have
different regulations on what is allowed on the frequency LoRa uses, if using
it is even allowed.

~~~
bigiain
Also which of the ISM bands are valid in which country. (We sold off the
bottom half the 915 band here to telcos, so only the upper half of it is
available in .au)

~~~
punkgeek
ooh. good to know. here's what we are doing now for the regions we know.
Someone is sending in a PR soon for the extra 440ish band in EU soon.

[https://github.com/meshtastic/Meshtastic-
esp32/blob/master/s...](https://github.com/meshtastic/Meshtastic-
esp32/blob/master/src/MeshRadio.h#L12)

~~~
bigiain
If you'd like some reference:

[https://www.acma.gov.au/step-2-show-your-product-
complies](https://www.acma.gov.au/step-2-show-your-product-complies)

Says:

(2) The 900 MHz ISM band within Australia is 915–928 MHz. 900 MHz ISM devices
working outside of this range cannot be operated in Australia (that is, ISM
devices that use the frequencies 902–915 MHz are not authorised for use within
Australia).

(3) Using the frequency range 902–915 MHz would interfere with Australian
mobile telephone networks. Severe criminal penalties, including fines of up to
$255,000, exist under the Radiocommunications Act 1992 for interfering with
radiocommunications services.

------
wildylion
You can try to contact those Russian guys at
[http://stratonautica.ru/](http://stratonautica.ru/). They were making a
project __exactly__ like this, with LoRa (with modifications?) but for
location tracking.

And if anybody is interested, I'm actively trying to cook up a neat solution
with DMR radios - it just works better than the LoRa ones so far :).

Into amateur radio, Digital voice, DMR, SAR, Location tracking and really
looking up to [https://www.sartrack.co.nz/](https://www.sartrack.co.nz/).

~~~
wildylion
Also, am Russian and [https://lizaalert.org](https://lizaalert.org) volunteer.
Would be happy to see you on the bands if you've got a call, come over to TG
250661 GMT+3, daytime. 73s.

------
dlumpkin
This is a great idea, especially for tracking kids. I'd love to leave one of
these in my kids backpack and know where they were without depending on a
cellular-device/service-plan/charging/etc

------
jokoon
It's not a new idea, but it's really a cool project, it just seems difficult
to democratize.

Problem #1: if users need a custom antenna, it's already a barrier. /me dreams
about the IEEE people designing standards that would enable smartphones to use
mesh networking... I guess a tiny antenna that can be attached to a smartphone
could also make it viable. If the antenna is not bigger than the phone, it
would certainly be marketed.

In my view, mesh radio could possibly compete with traditional ISPs, for
certain uses, so this kind of tech might not be funded for obvious reasons.

------
maufl
This is awesome! It looks like it could do several things for which I wanted
to have a device.

Offline GPS tracker with very long run time for hiking. I'd like up to one
month run time. On the other hand I only need low time resolution, one
waypoint each minute. It also does not need to send the location anywhere,
storing it local is fine.

Offline/Online GPS tracker for paragliding. Battery for one day, but also high
resolution tracking, about one waypoint per second.

Long range communication extender for my mobile phone that does not require
infrastructure like base stations. (For the prepper in me)

~~~
OnACoffeeBreak
This Garmin device in Expedition mode might work for you. It seems to have
configurable GPS logging and inReach satellite coms.

[https://forums.garmin.com/outdoor-
recreation/inreach/f/gpsma...](https://forums.garmin.com/outdoor-
recreation/inreach/f/gpsmap-66i/214719/gpsmap-66i-battery-life-i-m-on-the-
fence)

------
wwn_se
This looks promising.

Some form of Repeater/Server or similar feature would be great. A small
webserver that the phone can use as a backbone would be really useful. I might
even try to help with developing one.

------
reisr3
This is awesome, thanks for sharing! I'm considering using this for a project
where I need to measure distance between two nodes. Couple questions:

1\. You mention "location and distance" between member nodes. I assume this is
based on the LORA RSSI? How precise is the reading?

2\. Do you support the "TTGO LORA32"? Your Github Readme mentions it, but
Pages does not.

3\. Will the TTGO LORA32 and Heltec LoRa 32 measure distance without being
connected to a phone?

~~~
alfla
If the nodes have GPS it's fairly straightforward to calculate distance and
bearing.

~~~
reisr3
Right, and accuracy of ~9m makes sense for this application. The smaller
supported ESP32's, however, don't have onboard GPS. Does it use RSSI or need
to be paired with a phone?

Not that it's really relevant here, but I'm wondering if the LORA RSSI can be
used to determine distance inside 9m.

------
fh973
This is very similar to FLARM devices
([https://en.wikipedia.org/wiki/FLARM](https://en.wikipedia.org/wiki/FLARM))
for ultralights, gliders, etc. This is already broadly deployed (at least in
Europe).

You could check for any lessons learned there. I think you can discount any
flight users, because they would like to be seen too by other airplanes.

~~~
efesak
FLARM is very bad example especialy for DIY community. They have proprietary
chips, firmware and are running non opensourced protocol. Also they are
actively trying to prevent reverse engineering with cryptography and killing
old/diy devices with protocol timebombs...

~~~
fh973
Yes, I am also not enthusiastic about the crypto part, but then if it prevents
people from spoofing signals, it is probably a good decision.

The wikipedia suggests they use standard hardware components?

------
vkaku
Make the mesh affordable, keep making the drivers and interfaces clean and
reasonably easy to maintain.

In mass adoption, you want to keep the price right - so have a bulk pricing
upfront. Also, keep one access protocol you can access from a phone / PC /
most popular devices.

You're doing everything right. Try to get one great customer who can benefit
from this today.

------
deedubaya
Very cool.

There is a general fear in the backcountry Skiing community that any RF
devices might impede or negatively impact the use of search and recovery
beacons to locate buried partners in the event of an avalanche. Any
documentation/speculation on any potential interference?

~~~
bradstewart
I dabble in both backcountry and skiing and wireless devices, but I'm not an
expert on either.

My take on this: these devices should be safe to carry provided the hardware
is verified to not produce spurious harmonics (via FCC certification or other
means). The 900Mhz band used (in the US) by these radios will not interfere
with 457KHz signals used by beacons.

I wouldn't carry it in the same pocket as my beacon, but I would use this
device--definitely excited to watch the project's progress.

------
uitwear2
Would be great to have LoraWan redundancy, say with the things network, if in
range. From my experience, 8 days battery life with TTGO-beam is unrealistic,
unless sleeping for most of the time, or with some hardware modifications.
Great project, I will test it out!

------
mikehollinger
Go have a look at [https://www.project-owl.com/](https://www.project-owl.com/)
when you have a moment. They’re tackling similar problems but from a different
angle. Doesn’t mean there isn’t room for both!

------
wingworks
Sounds promising, but as someone who tramps a decent amount, I love as much
range as possible without needing a sat phone. I've got 2 gotenna, and they're
not so great, very short range. Maybe 1km in hilly areas.

------
notlukesky
It seems the website is down. I somehow wonder if it is from the Hacker News
crowd.

~~~
punkgeek
yeah - I was a dumbass when I typed the URL. the correct url is
www.meshtastic.org.

~~~
lultimouomo
Which means the post made it to the front page without a single person
clicking on the link. Classic.

------
anilakar
How will you make sure your customers will be in compliance when operating the
device? GoTenna used to have a nice photo gallery of people breaking the law,
i.e. using their earlier MURS-band mesh devices abroad.

------
SamPatt
This looks neat.

How does this differ from disaster.radio? More portable?

I ask because I really think these are important projects and I'm not sure
which to contribute my time towards.

~~~
punkgeek
We're working with those guys and might share the same protocol stack.
Discussions underway.

The difference is: disaster.radio is targeted as a "just in case emergency
radio build on custom hardware, that joins a mesh with other folks who bought
the same emergency radio."

This is a $30 radio (with built in GPS+radio+CPU+battery+OLED screen) already
available from a chinese mfg. Then you put our app on it and have a group
navigator you can use with your friends while skiing or hiking, instead of
buying a $100 closed source kickstarter (and it will run eight days on a
charge)"

------
EGreg
We have (local ad hoc social networking) software that would be very useful to
run on your mesh networks. What’s the best way to contact you?

~~~
punkgeek
sure! either chat on our gitter chat (link at www.meshtastic.org) or send me
an email at kevinh@geeksville.com.

------
aftbit
Nice, I just picked up two of the TTGO T-Beam boards.

~~~
bigiain
I have four on the way from China. I'm not holding my breath waiting for them
though...

~~~
punkgeek
tell me about it. I have a box of 5 I ordered before CNY. Still sitting in
china.

------
numlock86
What's the reasoning behind the $30? Seems pretty high considering the
hardware platform.

~~~
Acinyx
He didn't make the hardware, the higher end board with GPS, the TTGO TBEAM is
about this expensive if you also add a oled screen.

------
keiraarts
Please get a newsletter up - would purchase this in a heartbeat.

~~~
punkgeek
you can buy it now if you wanna guy a radio from aliexpress (not from us). see
our website for info.

------
timini
Has anyone here discussed the avalanche rescue as a use case?

------
dkdk8283
Anything like this out there for ethernet networks?

~~~
dicknuckle
you want 1kbps?

------
punkgeek
and I'm a dumbass and put a typo in the url. correct is www.meshtastic.org

~~~
lgats
[https://www.meshtastic.org/](https://www.meshtastic.org/)

~~~
dang
Fixed. Thanks!

------
ruslan
I'm just curious why my comment regarding patent was deleted ? Yes we
developed a device that implements this same idea of sharing GPS data over
mesh (868 ISM) network and patented it in 2014. The patent is still valid and
supported. If someone is interested in further development of this idea,
please contact me, we would be happy to sell this patent along with schematics
and source codes for fair price.

~~~
luma
Your post said nothing about the patent itself, and simply stated that this
open source project should be paying you. It's not exactly the best approach
on a site like this.

How about outlining the specific patent claims you feel are being violated
here, along with links to the patents in question? That approach would feel a
lot more helpful and a lot less like a shakedown.

If you've somehow managed to get a patent on sending GPS coords over LoRa I
think a lot of people in this space are going to be interested in that. Nearly
every LoRa application in the field is going to find themselves in violation.

~~~
ruslan
Don't get me wrong, I'm not a patent troll, neither I want to sue anyone -
that is against my attutude (I consider myself an old time hacker rooting from
late 80s :)). I'm just a co-developer and co-holder of the patent for a device
that does, among other things, exactly what topic starter described. We began
developing it back in 2011 and proceeded for several years, we had been
spending our free time and "pocket" money on it. In case you are interested it
took us to route and assemble 22 versions of PCB prototype of the main board
and 5 prototypes of a radio. We even exhibited it at one of the electronics
show in Moscow. As we failed to find sufficient investment to push it to the
market, we decided to freeze the project in 2015. In my initial comment that
was silently and shamefully deleted, I proposed to aquire our patent, that's
what might have any value today, as schematics and hardware are all outdated.
As mentioned above, discussing patent details on public is not any good idea,
that is why I simply pointed that I can be contacted on these matters.

I understand that hackers are strictly opposed to any sort of patents or
copyright. But it is not avoidable topic once you are into business of
settling or growing your own company (or a startup). And this is a startup
place, isn't it ?

~~~
luma
You sound like a reasonable person and I have every reason to believe you’re
acting in good faith. Your website suggests a patent pending in Russia. I am
completely unfamiliar with Russian IP law which might be the source of my
misunderstanding. Having said that, is there a reason you won’t provide the
specific patent(s) in question? I would presume they are a matter of public
record when they were issued.

~~~
ruslan
The site had not been updated when the patent issued, sorry about that. Patent
# RU 2559714. Exchanging GPS data is just a part of the device, btw.

