ResQ Search and Rescue Tools

So this took me MANY days to assemble and edit :)  It covers from the first testing up to to the aircraft GPS telemetry tests and I'm SUPER happy with how it came it.  This should help explain the history and all the instructions/info in GIT. much better to anyone wanting to build one. 

Net video will pick up after this one with the custom PCBs, more testing/tuning and more project building as I navigate all the hurdles a project like this presents.  I'm learning a TONNE and that's exactly what I shoot for in these.  Hope you enjoy. 

Eric

Well the PCBs have arrived in fine form from PCBWay.  Full disclosure- They support my YouTube videos by sponsoring orders like this (which is totally awesome). I placed the order like anyone else though and it was nothing special- just the $5 deal with black boards selected.  I have purchased boards from them several times and always found them to be excellent.

Since I will have plenty of spare boards I can definitely try to give a bunch of these away to anyone who wants one to build this project themselves. I put them up on my store at a price just to cover postage:

http://store.mkme.org/product/resq-printed-circuit-board-v1-1/

From Canada postage is expensive but I'll try to help people out..  You can always just have them made for 5 bucks at any board house but if you want one of mine go ahead. 

Thanks to Brian Lough's awesome panelising YouTube video these came out great!  I got right to work assembling the first air unit prototype

I am a bit short on SD modules and GPS units so I was a bit worried but turns out- I seem to have routed them correctly.  Yay for luck. 

Since I have now decided to put the OLED in to the air unit as well as the ground I need to make a new enclosure design.  No problem that Fusion 360 and my 3D printer cant fix. 

I am putting the GPS module inside the enclosure as well just to keep things clean. It can be routed outside if needed but I think in most cases it should be just fine.  These BN220s get a GPS fix even in my basement at times so it should be fine in most orientations on any aircraft. 

I finally made time to do the schematic layout and custom PCB.  It is pretty basic but that did not stop me from doing an absolutely horrible job in Fritzing

No matter- it allowed me to lay out the board and do a quick PCB layout which should hopefully work :)

I panelized them using an open source panelizing tool I found from a Brian Lough video:

And 

I sent them off to PCBWay for fabrication and fingers crossed- I should have about 60 boards YAY!  If they work (might take a miracle knowing my luck lately) I will try to give a bunch away to anyone who wishes to make this project.  They could actually be used for ANY ESP project where you want to have an SD card, OLED, GPS or combination thereof.

All files, layouts, Gerbers etc are in the GitHub Repo. 

Winning...maybe

This week my new VNA arrived which goes up to ~3 GHz enabling me to finally start testing/optimizing antennas.  Although initial testing seemed to working with my existing antennas I suspect with fully optimized/tuned antennas the results will be even better. 

Yagi's and Rubber-duck dipoles all ready:

This Nano VNA seems to work great. I will do some tests on lower freq antennas to compare it to my existing VNA which only goes up to ~1 GHz. Since I dont have crazy expensive lab equipment I've learned to make do by cross referencing multiple lower end tools.  Everything I read online points to these VNAs working just GREAT for this purpose though.  Here is a quick measure across a large portion of the spectrum- you can see the SWR isnt perfect but totally acceptable at 2.4:

Zooming in at our target and calibrating gives a better indication (picture missing)

Testing against some larger (somewhat higher gain) router antennas

I'm pretty happy now that I can work with the antennas properly and I'm finally learning a lot more about RF which is why I do these projects in the first place.  Fun

Last night was a big win for me. I was able to integrate the GPS code in to the existing logging code and it works :) All is pushed to GIT and I even released it as an Alpha so others can use it right away. 

I will be using the same codebase and schematic files for BOTH the air and ground based units.  The only difference will be that I will likely omit the OLED display on the air unit to save weight.  I may add battery and voltage regulators later but for now I will keep them external as it is much easier and the planes already have Vref supply on board. 

Right now it:

• Detects all Beacons and their mac addresses within range
• Detects All AP's in range
• Gets GPS Lat/Long positioning
• Gets GPS UTC Time
• Logs all the above to the SD card .csv file every time any device detected changes
• Displays the number of clients detected, APs detected, time and Lat/Long on the OLED screen live. 

YAY!

I actually didnt think I would get this far.  It works great and although not as good as sniffing the cellular data packets- this indeed works for a budget price of just a few bucks.  Next I think I will try testing out the UAV/Drone autonomous flight modes this weekend if the weather is good. Then more work on the schematic files and a custom PCB I think. 

Cheers

I needed to get the air unit sorted for the airborne hardware (the ground unit is a lot easier/simpler) so I decided to sort out the enclosure and test fit it this weekend. 

Here is the first test version inside the payload bay of the Nano Talon:

The CAD file originated from Thingiverse and the links are in my GitHub repo.  The Thingiverse customizer seems to be broken so I downloaded OpenScad and tried my own dimensions:

I was pretty amazed at how easy OpenScad was to work with (small files too). Opened up CURA and sliced/printed on my i3 Mega with no issues

All this will be included in the overview video coming soon.  I may need to resize the enclosure once I test the GPS unit (I really want try try to keep the GPS inside the case but probably need to run it to the top of the aircraft).  

Progress. 

Since I will be doing the ground YAGI and an air-unit version I spent some time testing the UAV to carry the payload. 

The Nano Talon is still my aircraft of choice here and I've finally made some time to properly finish setting up the autopilot and antonymous modes.  Last night I took a quick tuning flight with the air unit in the belly storage (no ground communication from the ESP-82666 though).

Setup video: https://photos.app.goo.gl/ZQPJnyyMeQhym54D9

The aircraft is broadcasting two telemetry downlinks in this test. One is my ~900MHZ control link which has full telemetry of all aircraft signals back to my radio and a second which allows monitoring and control via 433MHZ.  Both worked perfectly.  You can see the thunder storms building around me as I performed an auto trim cycle which centers the control surfaces for my new payload in flight. 

https://photos.app.goo.gl/KsjNefCDpH9coqWx6

Full DVR video: https://photos.app.goo.gl/KsjNefCDpH9coqWx6

Ultimately my video downlink failed and I have ordered a new diversity receiver module for my goggles as well as dropped the power output down on the VTX as it has been overheating in this >34C heat lately.  The new video receiver will be here next week and should work better in all conditions since it will now "stitch" together the two video feeds from my patch and my omin-directional antennas in to one much cleaner video.  Happy days. 

I have been working on the handheld unit as well so update on that soon. I was able to get the logging working properly and GPS also tested.  So far- it seems like I should be able to finish it up soon. 

Just need to make a case for the air unit and decide if I want to do live telemetry via LORA radio or just store the data on the SD card on the aircraft.  Lots of options here where I can even link multiple receivers or do more crazy stuff.  

Fist step is to finish the code...

I added the CAD files and links for a 3D printable enclosure to the GitHub repo. This is a larger project box for use with the breadboard testing variant. The final version for proper PCB will come later but some may wish to have theirs on a breadboard so this will probably be handy in the future 

The files are customized from another Thingiverse design you can find in the links/attribution. You can use the website customizer to change the design to suit your design for any changes needed.

What I thought would be an easy GPS re-integration was anything but. I had this working fine in the past when I originally tested this code as the ResQ-Air version inside my plane but there have now  been changes in the ESP board libraries/software serial (seemingly to support ESP32) which broke all the functionality for me so that serial was impossible. 

Updating the GPS libraries and board defs )added to my repo as well for future ref) finally got it compiling but the pins 3 and 4 dont work directly for the D1 mini and need to be swapped for their true numbering of 0 and 2. Apparently I had forgotten this since last year...

The BN220 is working at 9600 baud (default it ships with) on the pins discussed. I put 2 example sketches in my GitHub repo so anyone else can test theirs too if they need to troubleshoot without the OLED and SD card. 

Now to integrate all the code together which I have never done before (with OLED).  If push comes to shove I can omit the OLED entirely and just log to SD only or slap on a bluetooth module and just connect that to serial to use your phone or tablet as the interface.  Handy. 

Winning :)

All current code is now moved to GIT. It's open source now :)  

On the weekend I went out and did some range tests with the YAGI- there were so many people even in my remote area that it just spammed me with MAC addresses.  I good problem to have I suppose :) 

I ran in to some issues with the OLED and found I could NOT make the I2C display work at the same time as writing to the SD card via SPI.  No matter what I tried it seemed to not work. Eventually I guessed that it was a RAM issue and not a strange hardware glitch so I moved over to the lightest display library I could find (instead of the Adafruit one) and it now works!

I also got some neat comments pointing out that this may work quite well on game preserves to catch/track poachers. I see no reason it wouldn't as long as they are carrying a phone without wifi turned off. I suppose most do. 

Neat idea anyhow.