cool projects are rare here I found one
I want to show to you an undercover
Personal Communicator it includes a lot
of new technologies ESP 32 smartphones
Laura ple GPS mesh and as you see 3d
printing and it solves a problem which
could be seen as a human right
personal SMS style communication
everywhere in the world without the need
of any infrastructure and without mass
surveillance everything open source of
course how cool is that
create see youtubers here is the guy
with a Swiss accent with a new episode
and fresh ideas around sensors and
microcontrollers remember if you
subscribe you will always sit in the
first row
Laura technology already offers a big
range which can be extended by using
meshes when I was searching for such a
mesh network I found two projects
disaster radio and mesh tastic both
projects are founded in the bay area
around Silicon Valley and both want to
create independent communication meshes
that do not depend on infrastructure
disaster radio is more focused on the
rare event of a disaster mesh tastic can
be used whenever smart phones have no
connection or are dangerous to use so it
is much more attractive in this video I
will introduce the mesh tastic project
offer a glimpse into mesh technology
upload the project to TP e SP 32 boards
and build a small demo Network but what
is mesh tastic it is the virtue of the
two words mesh and fantastic and it
connects a bunch of TT Co tip imports
via an underground network each group
member has to have such a mesh tastic
device I use these t beams with Laura
and GPS and added and elate but other
devices are also supported
these boxes offer SMS style
communication you type a message on your
smartphone and it appears on all OLED
displays as well as smartphones of your
group because the tea beams have GPS
your location is shared with the group
so you can organize yourself the
position is also shared without GPS
because then mesh tastic takes the
position from the smartphone isn't this
fantastic how does it work the unreached
smartphone runs a mesh tastic app and
the communication between the smartphone
and the ESP device is done via ble the
communication between the mesh tastic
devices is done by a laura mesh network
all devices are part of this network and
can relay messages to others therefore
the reach of the network can be
significant it does not use any 2 3 4 or
5 G towers therefore it works everywhere
in the world and it is hard to trace
because the network providers do not see
your communication and position of
course only if you switch your mobile
comes off kevin Hester the creator of
this project is a mastermind he masters
all these technologies and brought them
together in a working and easy-to-use
project and now he has the help of
others to move the project forward so
let's dig into the details we all know
Laura ban the network with lots of nodes
and gateways here there is no
communication from node to node all
communication has to go via gateways and
the central infrastructure public 405-g
networks are also organized this way
this is why it is also easy to track all
of us meshes are very different much
more guerilla all participating nodes
are the same and are connected of course
not all nodes can connect to all others
because of reach limitations because
this fact meshes can become quite big
you could say why do I need Laura I can
create
ple mesh with my smartphone this is true
but its range would be minimal
maybe your voice has a bigger reach
because such a laura mesh can have such
a long range kevin built another feature
into his software you can create groups
that are separated from each other notes
from one group share the same channel
such a channel has a name and from this
name mesh tastic calculates a unique
combination of a transmission frequency
and a password in channel options you
should be able to select if you want
high volume at short range or low volume
but longer range the first is for large
groups with lots of interconnections the
latter for smaller groups with fewer
interconnections because of the password
more than one group can share one
frequency in the same location let's
have a closer look at meshes
particularly at radio meshes they are
much harder than wired meshes
because in addition to be ad hoc and
dynamically changing the topology the
medium is unreliable radio connections
sometimes work and if you move a few
meters stop to work quite a few PhDs
were awarded to finding the best mesh
strategy I decided to use a particular
one to understand how such strategies
work the name of this particular
strategy is Batman I thought that this
must be a good if not the best strategy
available with such a name but how does
it work if a node joins a network it
does not know a lot in our case only the
frequency the spreading factor and the
password this is why it sends a hello
message also called a GM or originator
message to find the best nodes around
its location all notes receiving the
message retransmit the OGM received from
the best neighbor they transmit it only
once to avoid network congestions by oh
GM's they also keep this best node
information
the right note to use for a message
towards the originator of the OGM like
that each note only has to store one
best note for each other network note
there is no database about the overall
network structure as seen before the
topology can change and therefore oh
GM's have to be sent out from time to
time to maintain the best routes
fortunately this algorithm is already
implemented and we do not have to care
if we do not want the next problem Kevin
had to solve was to save energy the TPM
has an 8650 battery onboard we all know
that the ESP 32 has to sleep most of its
time if we want to get long battery life
fortunately the lower receiver can't
stay on listen to incoming messages and
wake the ESP if it got a message by the
way for people interested in learning
how to program this project is an
excellent example it uses platform i/o
and Kevin has a professional programming
style it is for sure worthwhile to look
into the code also if you are interested
in how to use Laura modules and ble you
can learn a lot now I would like to show
you how it works we find a ready-made
pin file on the project page select one
for your region and also download ESP
home flasher select the comm port and
the bin file hit flash ESP and radius
the device
of course you can also download and
print this cool 3d case from thinners
each mesh tastic no it has to be paired
with a smartphone this is best done if
it has a small wallet if as I did you
buy t beams without all it it is easy to
mount one yourself if you choose the one
with VCC and ground in this place it's a
no-brainer otherwise you have to
improvise during pairing the display
shows a number and if you heat this
number into the app they are paired i
used the default group and everything
was ready to go one smartphone belongs
to me the other to joe i can see the
position of us on a map and if i send
him a message
i see it on both screens and he sees it
also on his smartphone and of course he
can answer me i only have two t beams so
i cannot show you how all others would
get the same message very important if
you use the right lower frequency for
your country everything is legal because
it uses the same ASM frequencies and the
same modulation as TTN for example now
the interesting question what is the
range no it will most probably not work
across the 200 kilometers from video
number 120 but it will work on a line of
sight for a few kilometers and if you
have a mesh of several nodes the range
will be extended if one or two nodes are
elevated and can be reached by many
other nodes your network can become
quite big without any infrastructure
needed and as said before it is hard to
track because first this is a new way
and most organizations interested in
spying on you probably do not watch this
channel and second the transmission is
password-protected so somebody has to
put some effort into it if he wants to
read your messages now a few words to
the performance the transmission speed
of Laura is quite low so do not expect
wonders and because the device sleeps
between transmissions you
have to wait for the next timeslot for
communication this time can be adjusted
and Kevin has already put a feature
request to change the sleep time
from the smartphone like that if you
plan a short events of only a few hours
you can decrease sleep time to get more
speed and also less latency of course
you have to charge the device earlier or
change the battery but even when the
device always-on it should run for 24
hours on one battery and a word about
quality the project is complex and many
things can go wrong
I had issues during my tests and would
not recommend its usage in a productive
environment but maybe you sign up as an
independent test person for the project
this would be extremely valuable for the
project team because having independent
testers always increase the quality of
products and a word about future plans a
few people are interested in building
specialized hardware for this project
interestingly they will not use the ESP
32 they will use the NRF 52:xx chips
from nordic semiconductors these chips
are perfect for low-power ble projects
for me this is particularly interesting
as you might know that I want to use
these chips for my future projects this
is all for today
I wish this project good luck on its way
summarized mesh tastic provides a
underground communication possibility
for groups it is based on a Laura mesh
network it uses Android smartphones for
message entry you can see the messages
either on the smartphone or on a small
omelette on the device the positions of
the group members are also displayed on
a map on the smartphone radio meshes
need specific strategies to adopt to
ever-changing topologies we looked at
how the Batman protocol works it is
effortless to build a mesh tastic device
because you only have to flash ATP with
a ready-made pin file the project still
is in development so expect you have to
do some
sting and not everything works
flawlessly Kevin started a port to the
NRF 52 processors very promising even
the famous youtuber sexy cyborg seems to
be interested in the project as always
you find all the relevant links in the
description I hope this video was useful
or at least interesting for you if true
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bye