2017, in case you don’t remember, was a terrible year for the Caribbean and Gulf coast. Hurricane Maria tore Puerto Rico apart, Harvey flooded Houston, Irma destroyed the Florida Keys, and we still haven’t heard anything from Saint Martin. There is, obviously, a problem to be solved here, and that problem is communications. Amateur radio only gets you so far, but for their Hackaday Prize entry, [Inventive Prototypes] is building an emergency communication system that anyone can use. It only needs a clear view of the sky, and you can use it to send SMS messages. It’s the PR-Holonet, and it’s something that’s already desperately needed.
The basis for the PR-Holonet is built around an Iridium satellite modem. To date, satellite communication is the best way to get a message out to the world without any infrastructure. It’ll work in the middle of the Sahara, the depths of the Amazon, and conveniently anywhere that was just hit by a category five hurricane.
Along with the Iridium modem, [Inventive Prototypes] is using standard, off-the-shelf equipment to turn that connection to a satellite network into something any smartphone can use. That means pulling out a Raspberry Pi, of course. But building a project for areas that were recently ravaged by hurricanes is no easy task. The enclosure it the key here, and [Inventive Prototypes] is using some great water-resistant, dust-proof junction boxes, solar panels, and a whole bunch of batteries to keep everything humming along. It’s a great project and something that was desperately needed a year ago.
Solar panels + Hurricane/Cyclone/Typhoon = light flying stuff that kills.
A safer solution would be an underground diesel generator and fuel tank(s). Although with long term storage microbial growth in the diesel fuel will cause clogs in the pipes to be a major issue. Maybe there is some fix for that now, the orange microbial sludge used to be an issue years ago. My guess with be that biodiesel has created an even better growth medium.
I think this is intended for after the event, not during. Something that can be kept in the basement in a suitcase, or flown in by the emergency response teams.
diesel bactericide has been available for long time now. To what degree biodiesel would have a simiar problem I wouldsn’t know
“To date, satellite communication is the best way to get a message out to the world without any infrastructure.”
Shortwave.
Oh, old fashioned but still workable.
Depends on the data rate, bandwidth, and modulation. If it is near real time high resolution satellite images of the disaster zone, to help rescue workers, HF may not be the be the optimal. But it it is just a couple of images, with 20kHz of bandwidth and modulation similar to that used in Digital Radio Mondiale (DRM – Coded Orthogonal Frequency Division Multiplexing) you could transmit 30.6–72 kbit/s of binary data.
Shortwave can fall victim to poor propagation. The limited bandwidth of that range of spectrum means data rates less than many would expect to be able use during an emergency. The SW TRANSCVR in my station and the network I use it communicate with are infrastructure.
It would be useful to incorporate gotenna mesh devices to work with this system.
I’m a bit confused, the airport on St. Martin reopened two days after the hurricane and many hotels and restaurants reopened in February.
This is not going to work when you need a cloud account to make this work.
This is not going to work when you need access to a satellite communications transceiver in a disaster zone.
The cost of dedicating a satellite communications receiver for this project will be more than the cost of a house.
The Iridium business model requires you pay for 1 year of service up front.
The Iridium satellite can only handle slow narrowband text or single voice communications. It will not handle high speed or multiple users at the same time.
“This is not going to work when you need access to a satellite communications transceiver in a disaster zone.”
This device -is- the satellite communications transceiver. That’s like saying food is not going to work when you need access to food in a disaster zone. And there are people that go into disaster zones to help undisaster them, who will bring food water and (if this device is realized) some of these devices.
“The Iridium satellite can only handle slow narrowband text or single voice communications. It will not handle high speed or multiple users at the same time.”
An SMS is about 140 bytes of data, even in a cell phones tower-handshake ‘ping’ real SMS travel through, it’s closer to 400 bytes. That’s an ideal use of Iridiums low data speeds.
Also from the birds perspective, only this device is seen as “a user”, all the actual people are talking through it. Kinda like a NAT router to the Internet. The far end only sees one thing, although you likely have many devices behind it.
“The cost of dedicating a satellite communications receiver for this project will be more than the cost of a house.”
Actually the transceiver modem is only like $400 USD. Not cheap I agree, but not quite as bad as you say.
Also, although the device offers up a web app it runs while acting like an access point for those phones and laptops to connect to, it does have to send that data over iridium to a server running elsewhere to convert that into actual SMS messages. That server will cost money to maintain, yes.
But in this case I think the cloud is a good use case. Think about it, as a customer I would get an AWS image and some number of these devices. While the devices are in my possession and unneeded, no servers are up.
When needed, I can spin up as many of those AWS servers as needed, and then deploy the devices. As they become unneeded again, the devices are picked up and once some number are retrieved, you can shutdown an AWS instance.
That would be far cheaper to pay as you need, instead of keeping a colo server running year round even when not needed.
The 1 year of satellite service up front is a big downside though.
SoD (Service on demand).
This to a T!!! Thanks for the awesome explainer. This is *exactly* the use case scenario.
To your point on a one year satellite subscription though, not for this system. It is pay as you go. You have to buy all the “credits” you think you’ll need up front. But you pay an “activation” fee monthly only for the months you need the system active. And the credits don’t expire.
:)
Thank you!
– inventive.prototypes
The well thought of Garmon Inreach 2 way texting handheld surely already covers this disaster requirement. Access to the LEO Iridium sats. is not free, but charging plans allow for “free parking” until the service is needed. ZL2APS
Not exactly revolutionary. The huge downside I see is that a) satellite data is slow and spreading it to everyone in a 1 mile radius is going to make it useless, and b) satellite data / minutes on the Iridium network is absurdly expensive.
As a ham operator, I look to the many digital modes hams enjoy. If all you need is a picture of something, slow scan
television (SSTV) will work quite well. Laptops or notebooks can run the MMSSTV software with no problem.
For text descriptions, the various modes already available work well. One of the older protocols, RTTY (radio teletype)
is good although somewhat slow. There are a multitude of modes available today, JT65, FT8, PSK31…..
An antenna can be as simple as a long piece of wire. Then of course. there’s the good old standby that can be done
with even a flashlight. Morse code. With solar power, a truly portable station can be set up just about anywhere.
Serval Mesh Project anyone?
Where the facts are dated this must be a file Brian had is reserve for a slow for him day, forgetting to see if it needed updating. I have to feel St. Martin has been heard from by now. Also PR-Holonet has feature somewhat recently presented here. This depends on cellular network. Even if those networks survive or restored quickly access to them could be limited to official local government, law enforcement, and first responders. With everyone else getting short time slot of access, stating the oblivious what is or in’t the plan is going to vary according to location
Iridium has one essential flaw.
It will cost you at least 50$ each month you don’t use it. You can not have a device waiting for disaster comms without a subscription, because without communications you cannot activate a subscription.
Thuraya has a more workable plan of 10$ per 24 Months. But on the downside it is not available in the americas region
You can yell all you want into whatever device you want, it is all for naught if the people on the other end don’t care or respond…
Irma survivor. The helpful response was deafening. No one gave a shat.
What’s the USA response like in Hawaii?
Why are you asking me?
Disaster Area? I thought that Hotblack Desiato was taking a year off to be dead for tax reasons…
In any reasonable country the authorities have all the equipment for comms they really need and all the other countries are to poor to afford this. Solution without a problem.