The smartphone continues to play an increasingly important role in search and rescue with all manner of apps available to assist SAR members in the field. More than anything else, I use my phone for land navigation. In fact, unless the weather is really bad, I rarely pull my dedicated GPS out of my bag. With my phone I can easily enter waypoints, scroll around on a map, and even use a decent compass. Earlier, I've mentioned specific apps that are handy, as well as ways to keep your phone powered throughout multiple operational periods, but there still remains the problem of moving data on and off the phone outside of cellular networks, and with minimal client-side requirements. Sure, it is relatively easy to provide FTP access to some command post files, but that would require that end users understand how to FTP and have the proper software loaded. This is not easily accomplished when there is no cell coverage. Enter Piratebox.
Piratebox, and its fork LibraryBox, allow file sharing outside of any internet connection. LibraryBox is a fork of the Piratebox project, and has similar functionality. The differences primarily lie in the ability to upload. Piratebox has a provision for file uploading by others, while LibraryBox is a, primarily, one-way operation; there is no provision for upload. Since it would be nice to be able to easily collect things like GPS tracks from phones, I figured that the ability to upload files would be helpful.
There are a handful of routers that are known to work with the Piratebox software, and I chose the TP-Link MR3040 because it comes with an integrated battery, and charges via a micro USB cable. To build your Piratebox, you flash the router with new firmware (OpenWRT) that has been modified to work with Piratebox, then install the Piratebox software. I won't replicate the directions here, but I followed them on the Piratebox site, and they worked fine.
When you are finished, you are able to share any files on an attached thumb drive. People access the files by connecting to the wireless router (Connect just like you would any WiFi hotspot. This one won't have internet access, though.). Once they are connected, they will be redirected to a browser window that shows a place to view files, and a box to upload files.
The whole install and configuration took about 30 minutes. I did make a few modifications, however. I modified the landing page text to reflect the use in SAR, and I changed the header image. I used the instructions from this thread to accomplish this. I changed the default SSID to "SAR-Files SBSAR" and configured file uploads to go to a different directory using the instructions on this page. Since I didn't want just anybody accessing the files on the Piratebox, I also put a password on the WiFi access using these instructions.
My goal with this project is to make .GPX/.KML files for all search assignments available for download to searcher's phones. Also to be included are PDF maps and other documentation such as photos, track prints, etc. So, rather than getting an assignment, and spending time entering in waypoints and such, the searcher can quickly download his/her area to include on the mapping program on their phone (Backcountry Navigator, Locus, Gaia, etc). The command post would load up the flash drive with the files, plug it into the Piratebox, and set it on the check-in table for SAR members to access at their leisure.
When the team returns, and has tracks and/or photos on their phones, they can connect to the Piratebox again, and upload their files. Later, the command post can pull the thumb drive and download all the files uploaded by the teams. Since everything is done with a web browser, no special software needs to be installed on the end-user's phone. This is key. Any solution that is designed to work outside of internet access, can't require a special app download since there will be no way to download the app without prior planning.
I have yet to try my Piratebox on an actual search, but it won't be long before the call arrives, and I will be able to give it a whirl. I will continue to update the links that I have found useful with this project at https://pinboard.in/u:jlehman/t:Piratebox. All of the links mentioned in this article are there. Drop me a line if you have any questions.
You can register at the event on Friday, September 30th at our Base Camp or you can pre-register online at www.desertrun.org and get a $5 discount. We have a schedule of events and a Menu for the weekend in a flyer that's available at our website (www.desertrun.org). You can also visit us on Facebook: desert run - morongo basin search and rescue. Also, the flyer will provide you with any other information that you may want to know about the event. Or you can call Renee @ 951-203-6816 or Josh Lewis @ 760-275-8514. Thanks for your support of the Morongo Basin Search and Rescue Team. All profits go toward support and training of the Unit!
The formula for determining the lecture date for the Basic Mountaineering Course has changed. In the past it was held on the weekend before Thanksgiving. The new formula is to hold it on the weekend directly following the second Friday of November. Hence this year it will be held November 12 and 13. Please spread the word and mark your calendars. More details concerning signups will be distributed via email and online out as we get closer.
SAR members representing West Valley SAR, Cave and Technical Rescue Team, San Gorgonio SAR, SB Mountain SAR, Morongo Basin SAR, and Wrightwood SAR completed the 2016 Rope Rescue Operators Course. Congratulations to the 14 rescuers as they continue to expand their responsibilities and continue to serve the citizens of San Bernardino County and the state.
After many months of waiting, I was finally able to get my hands on a pair of GoTenna devices to field test. These devices are VHF radio transceivers that pair via Bluetooth that enable two phones to pass text messages without requiring any cell service. The required phone app allows for text messages, pinging connectivity between devices, and the swapping of location using the phone's onboard GPS to fix position. There are also downloadable base maps to display position data.
The pairing process was quick and easy with the Android phones used in the test, and the software and hardware performed without any difficulty. The interface is similar to most of the available messaging apps. Although, only text can be sent, so there is no photo sharing or other file sending available.
While testing one person attached the device to his pack according to the suggestion of the manufacturer, and the other person placed it in his pocket and started off on his mountain bike. We communicated via 5 W VHF radios with rubber duck antennas to compare the coverage. Obviously, as long as the GoTenna was in the bike rider's pocket, the connection was severly compromised. Periodically the rider would stop, remove the device, and attempt to communicate. This was done until we could no longer maintain a reliable connection. As expected, the most reliable communication came with optimized antenna location. If both ends of the communication held their devices high, and vertically polarized, the likelihood of a reliable connection increased.
In the environment tested (shown on the map to the right) the furthest that we could maintain a connection was approximately 0.6 mi. This was challenging RF terrain, however. The blue shading on the map is a line of site layer, so we were able to maintain some modicum of communication outside of this region. By comparison, the 5W VHF radio allowed reliable communication greater than 1 mile in this same terrain.
We were operating in the MURS band with the voice radios. A bit of testing shows that the GoTenna may be operating on MURS channel 1 (151.82 MHz), so we avoided this channel, and used MURS channel 5 (154.60). We noticed that if you were transmitting with the 5W radio on channel 5, it would interfere with the GoTenna messages. This may be something to consider since much of our SAR work is in the neighborhood of this portion of the spectrum.
Given the additional overhead of having to pair a smartphone to the device, and the limited range, the GoTenna doesn't seem to provide any significant communications advantage over, or in addition to, the typical portable radio. Still, this is the first generation of such a device, and for those of us who are attracted to all things RF, it is most intriguing.