[HN Gopher] Meshtastic: Open-source, off-grid, hiking, climbing,...
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Meshtastic: Open-source, off-grid, hiking, climbing, GPS mesh
communicator
Author : GNU_James
Score : 133 points
Date : 2021-01-31 18:43 UTC (4 hours ago)
(HTM) web link (meshtastic.letstalkthis.com)
(TXT) w3m dump (meshtastic.letstalkthis.com)
| morpheuskafka wrote:
| So these are using LoRa (902-928MHz) as the actual frequency for
| text transmissions? This is really an exciting frequency that's
| been around for a while and has a lot of potential for
| disruption.
|
| Fun fact--there is a completed WiFi standard for this frequency
| (802.11ah / WiFi HaLow), but as far as I know, there have never
| been any chipsets made for it.
| bigiain wrote:
| Yes to "LoRa", but not necessarily on the 900MHz band. I have a
| few all using boards with 433MHz LoRa radios, most of the
| hardware supported is available in 433/815/915MHz variants. (In
| fact, I'm fairly sure most of the chipsets are capable of all
| those frequencies, and the only real difference if you buy the
| 433MHz version is the antenna they include.)
| bjconlan wrote:
| Yeah, this has been my experience too. Generally you use the
| frequency that has been legalised for use in the region you
| operate it in. I wonder if this automatically switches to the
| suitable frequency based off coordinates (when using a gps'd
| board) I'm sure it would be trivial to implement. Ah good ole
| opensource. This really is a great solution, riding around
| New Zealand the only solution is a SPOT tracker which charges
| like a wounded bull so I love that this is disrupting this
| space (and using clever tech - heck might throw one of these
| on the moto just to use it for security)
| morpheuskafka wrote:
| Right, it uses that in Europe as they don't have 900MHz. I
| think in the US there's some periodic use only requirements
| for 433.
| slothtrop wrote:
| In theory could range be extended (for this tech and similar
| types) through a string of nodes to cover Metropolitan areas?
| geoah wrote:
| I was hoping for something like this but unfortunately LoRa
| seems pretty meh if you don't have line of sight between the
| devices or maybe open enough areas that don't drown the
| signals. I was hoping that it could go for a couple hundred
| meters in urban areas (was trying this out in the outer London
| zones, UK) but the results were pretty bad. Reception was
| spotty the moment direct LOS was lost and non existent ~10m
| after that. Not even worth mentioning the results if one of the
| nodes was inside a building.
|
| If anyone had any success in dense areas I'd really appreciate
| any links to the hardware/antennas/firmware/software you used
| to get good results.
| bigiain wrote:
| Antennas and height make a huge difference. I've got a hop
| from my place to a friend that's a little over 3km non line
| of sight (terrain/hill between). Can't do that with the stock
| rubber ducky antennas, but with a swr meter tuned home made
| dipole antenna on a 4m pole on my roof it's rock solid (using
| 433MHz, not sure if 815/915 would get that far).
| slothtrop wrote:
| Ah I see. Got too excited.
| bitxbitxbitcoin wrote:
| Yes. Here's a map of existing (albeit self reported) nodes that
| you could theoretically mesh with. [0]
|
| [1] https://canvis.app/meshtastic-map
| [deleted]
| Luker88 wrote:
| The project is really interesting and I think I am going to try
| it.
|
| It looks like it's text only? would it be possible to add a very
| filtered, low-bandwidth audio stream since the phone can do all
| the calculations?
|
| I have no idea on the actual bandwidth of these devices,
| wikipedia says LoRa is 0.3-27 Kb/s and Opus should work decently
| at ~10Kb/s I think. So maybe?
|
| Although audio would probably be half duplex and only point-to-
| point instead of mesh, but it still could be interesting
| s800 wrote:
| The duty cycle requirement preclude this type of use. You
| should be "off the air" ~99% of the time.
| morpheuskafka wrote:
| Another thing to consider would be latency due to
| retransmissions. Something like voice notes would probably be
| better than a live call send it could be re-transmitted as many
| times as necessary and broken into small chunks.
| voltagex_ wrote:
| Have a look at Codec2 [1]
|
| 1: https://en.wikipedia.org/wiki/Codec_2
| vvanders wrote:
| Codec2 is part of it but you need a lot more pieces on
| top(framing, modulation, etc). LoRA doesn't really have the
| bandwidth for Codec2(for a few reasons, mostly power and the
| way LoRA handles channel congestion).
|
| M17[1] has been making really big strides in this space and
| really excited to start seeing a proper open hardware/open
| source digital radio stack.
|
| [1] https://m17project.org/
| wyck wrote:
| I would love this for my dog, she runs in the woods and I like to
| know where she is. I've tried a Lidar collar but the range is too
| low. The only other option is a cell phone in a case (which is
| used by search and rescue) but it's to expensive since you need a
| cell phone plan, and it's and too bulky to attach to a moving
| animal.
|
| There is a market for this, I'll help prototype it , someone
| start a company to track dogs and children (out playing, biking,
| skiing) :)
| semi-extrinsic wrote:
| How about the Garmin T5? It is literally made for this, no?
|
| Edit:
|
| https://www.amazon.com/Garmin-T5-GPS-Dog-Collar/dp/B00L3C5ED...
|
| It's a bit of a pricey solution, and typical range is 4-5 miles
| I believe. Seems to be popular with people who use their dogs
| for hunting moose etc.
| conk wrote:
| There are GPS+LTE pet trackers like Whistle dog collar that
| seem reasonably priced.
| s0rce wrote:
| Having trouble figuring out the subscriptions costs on their
| website.
| maxerickson wrote:
| https://www.whistle.com/pages/gift
|
| That page is pretty clear on mobile, a bit under $100 a
| year for the subscription.
| bitxbitxbitcoin wrote:
| Patiently waiting for my T-Beam to arrive so I can try this out.
|
| This is an open source alternative to the popular GoTenna devices
| and if any HNers can point me to other options in this space I'd
| love to try them all out.
| GNU_James wrote:
| Isn't the radio modem proprietary with a blob?
|
| https://archive.is/lEfpQ
| duckfang wrote:
| I believe so, yes. But in all seriousness a line has to be
| drawn somewhere about open source'ness.
|
| For example, there's a few ways to remediate that. My
| preferred is a reference Gnuradio flow that, with an SDR,
| allows for communication with their device network.
| Secondarily, open firmware would be good... but with open
| firmware still results in closed silicon (and not everyone
| has access to a fab!).
|
| Closed source isn't always enough to run me away. Closed and
| closable interoperability does.
| bigiain wrote:
| Yeah. Things get a little fuzzy this close to the hardware.
|
| The "open source" project is a (platform.io) project that
| runs on the ESP32 (or a few other similar enough)
| microcontroller. It controls the LoRa (totally closed)
| firmware on the LoRa components (and GPS as well).
|
| Even your Gnuradio setup has similar black box firmware
| underneath that it relies on (unless you've got to
| extraordinary lengths to ensure the machine it's running in
| has no propitiatory firmware for things like disk/ssd
| controllers, USB controllers, battery management systems,
| etc. )
| COGlory wrote:
| This is absolutely brilliant. If this works as advertised, it'd
| be trivial to add mesh network capabilities to lots of the
| mountainous areas I'm frequently in while hunting or hiking or
| what not. That would be huge for safety, and substantially
| cheaper than a sat phone.
| bigiain wrote:
| Careful you don't expect too much here. At long range the
| bandwidth is very very low and latencies are very very high.
| Meshtastic will never be a replacement for a sat phone. Think
| of it as more like a two directional pager. Short text messages
| with latencies possibly as high as 40 or 50 seconds.
|
| Lots of people disappear from the forums when they realise they
| won't be able to something like use this to stream YouTube to
| their off grid cabin...
| COGlory wrote:
| Right, I was more thinking a mesh network solar operated to
| let people report their location and status across rough
| terrain. I may try making a few of these over the year for
| next hunting season, and place them in a mile or so radius
| from basecamp for the duration of my trip, anyways. That way
| we could split up but still maintain contact, get help if we
| shoot an elk, etc. We're definitely outside direct walkie-
| talkie range, and I'm in the only one in the group with a
| HAM, so this could be pretty useful.
| vvanders wrote:
| > safety, and substantially cheaper than a sat phone
|
| I agree that it's a really cool project but I personally would
| not use it as a primary safety mechanism.
|
| I've got a ham radio license and I see the same mistake with
| people who think a 5W VHF handheld or 10W HF radio will help
| them in dire straights. HF isn't reliable enough and all it
| takes is a little terrain to block VHF. You're also not
| guaranteed that there's even anyone on the other side of the
| radio if you really need help.
|
| I would recommend a SPOT or inReach as a your primary safety
| device with this as a (neat) backup. All they need is a line of
| sight to the sky which is much easier to do than either LoRA,
| VHF or HF.
|
| [edit]
|
| If you want a good idea of the limits of LoRA Ars did a pretty
| good write-up a few years ago:
| https://arstechnica.com/gadgets/2019/10/lostik-usb-lora-radi...
| . You'll see that even in a few mile radius there's plenty of
| places where even a high-end LoRA device drops out because very
| few radios can go directly through terrain(if you're curious
| https://en.wikipedia.org/wiki/Through-the-earth_mine_communi...
| covers some aspects).
|
| It is a _really_ cool modulation for low power but it 's still
| subject to the physics of radio propagation.
| npsimons wrote:
| I'm in mountain rescue and I'll second all of this. It's why
| we will set up repeaters, or station people as repeaters if
| we have enough people, but more often than not, we are out of
| radio communication for hours on end, despite all parties
| having the necessary equipment. More often than not, we'll
| use inReach texting to maintain comms.
|
| But projects like this excite me for future directions.
| Sometimes when we've been in areas with cell phone coverage
| (some wilderness in SoCal has coverage), we will be able to
| see tracks in SARTopo update live from teams in the field.
| It's really cool when it works!
| vvanders wrote:
| Yes!
|
| I'm totally 100% on board with this as a secondary
| data/telemetry mechanism.
|
| For all the open source software out there it's a tragedy
| that there's less of that culture in ham radio(which is one
| of the primary charters of the spectrum-carve out we have).
| Stuff like this and the M17 project give me hope that we
| might some day have something more than just the dumb AX25
| packet radios(which are stuck in the 80s at 1200bps and
| _zero_ FEC).
| COGlory wrote:
| I think that the mesh aspect of this would be a substantial
| improvement over VHF/HF radios. I'm sure I'm wrong, but I
| don't know of anyone that is running a mesh VHF or HF system
| in the mountains. I always carry my HAM when I'm out, just in
| case anyone else is, but obviously that's truly local
| communication and has the downsides that you mention.
|
| With a strategically placed mesh network and some solar
| panels, you could potentially overcome a lot of the downsides
| of radio because you could target high areas, such as
| mountain peaks, to help bridge those obstructions.
|
| I definitely don't disagree that the #1 safety device is a
| GPS/sat phone, but those are prohibitively expensive and most
| people don't have them. If we could get some solar powered
| radios along ridges, and a decent percentage of people
| carrying them, I think there could be a very comprehensive
| mesh network that would work for most needs. Bearspray is
| already pretty ubiquitous, I don't think it'd be that hard to
| get people to bring a $30 mesh radio with them as a routine
| thing.
| vegardx wrote:
| I would be surprised if it was cheaper than something like
| a Spot or Garmin inReach when you factor in the cost of
| building out and maintaining such a network.
| vvanders wrote:
| Take a look at the Ars article, it's _really_ hard to get
| coverage in moderately flat areas over a reasonable
| distance(1m+). You also quickly start running into the
| Hidden Node[1] problem or the N^2 aspect of channel
| congestion(which is why LoRA has such low throughput).
|
| Cell companies spend billions on this and even then you'll
| still have gaps outside of the metro areas, and they're
| using much more advanced modulations like CDMA and FDM/TDM
| with a central coordinator.
|
| I've talked with a fair number of people who maintain
| commercial repeaters in mountain areas and those can be
| incredibly difficult(combination of hard access in winter,
| large temperature swings and theft of solar
| panels/batteries) so which it might be possible, my guess
| is the level of investment just doesn't pencil out for the
| usage.
|
| [1] https://en.wikipedia.org/wiki/Hidden_node_problem
| COGlory wrote:
| Thanks for the detailed response!
| vvanders wrote:
| No problem, it's a really neat domain and there's a
| fascinating intersection of physics + math(you can
| reconstruct freq mixers/modulation with a basic trig
| foundation) and practical application that makes radio a
| really cool space.
|
| I also think that there's still untapped potential for
| secondary services and the like so it wasn't my intention
| to dissuade anyone form picking one up and giving it a
| try.
| tpmx wrote:
| https://msglab.co/room/lo-ra-msg is a pretty neat
| concept/prototype.
| s0rce wrote:
| Very cool, I just ordered a couple radios to play with. Looks
| like the app is Android only although an iPhone app is under
| development. Any recommendations for a cheap android phone/tablet
| to use mostly for this application?
| bigiain wrote:
| I'm using old Samsung S3 and S4 phones with Android7 Lineage on
| them. I would go any older than that, and the Bluetooth works
| more reliably if you can get Android 8 or newer (none of the
| Lineage images of 8 will boot on my S3s.)
|
| You don't need anything that you probably couldn't find in the
| back of your or a family members junk drawer...
| pqdbr wrote:
| Me and my friends would pay for this. We fly paramotors and
| almost every weekend we fly to places with no cell connection.
|
| Plain old radio is terrible (there's always someone transmitting
| all the time without realizing, blocking communication for
| everyone else) and the ability to check each other's GPS position
| would be awesome to know if the whole party is still flying
| together.
| bigiain wrote:
| That's actually one of the driving force use cases for the
| project founder, so it's reasonably likely to eventually work
| well for that.
| myself248 wrote:
| Meshtastic has been talking about merging with Disaster.Radio for
| eons, because the two seem to have a lot of conceptual overlap. I
| can see uses for both feature sets and would love if they were
| just one thing.
|
| It sounds like that's just not happening?
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(page generated 2021-01-31 23:00 UTC)