Mobile GPS logging Geiger Counter Project

Hi all!

I recently bought myself a DP-66M from ebay, then another one, then a NetIO GC-10 and I have another on the way. Maybe a different one soon? It's fair to say I have been bitten by the Geiger counter bug!

I am building a static outdoor monitoring station at home, monitoring 24/7, but currently waiting on parts from China. In the meantime I have been playing with the GC-10 and built a prototype mobile GPS logging unit to take on my travels. I live not too far from Heysham power station and the Westinghouse Springfields nuclear fuel manufacturing site, so I will be having a drive around them soon to see if there are any elevated levels





The unit uses an Arduino Pro-mini at the core, with a GY-GPS6MV2 GPS receiver module and a Catalex SD card module. All are cheap as chips on ebay from China. The Arduino takes the GPS data via RS232, the CPM from the GC-10 RS232, does a little processing and parsing of the data and shoves it on the SD card in a CSV. Each time the logging is started it creates a new filename generated from the date/time so should be easy to get the data and upload it to Google maps or something similar (I haven't gotten round to that part yet). There is a bi-coloured LED that changes from red to green when a good satellite lock is acheived and it will not start to log the data on the card until a valid date/time is received from GPS. This keeps the CSV files nice and tidy with proper logs only.

In testing I have had issues with the batteries (2x AA via a 5v boost converter to the GC-10), but I think that was down to bad batteries, so I am currently testing on fresh batteries. I checked the current and it is pulling just under 4mA at the batteries, so whilst they won't last long, it should be enough for some walky-walky monitoring. I plan to add an external GPS antenna/socket and maybe a couple of 18650 Lipo batteries and charger/protection circuit/module. I think it would be nice to be able to power from either the car 12v or maybe a 5v USB type power input that would charge the batteries when plugged in, but that is for another day.





I tried uploading the zip file containing the source/schematic etc here, but it failed. Probably due to the zip size (12Mb) so I have uploaded it to my server for you to download here: GPS Geiger Counter

Contained in the zip are some photos of my prototype build, the Arduino source and schematic so anyone that wants can go build one also! Some knowledge of electronics/arduino will probably be needed as I have not, nor intend on doing a step-by-step.

I am licensing this under:
Creative Commons Attribution-ShareAlike 3.0 Unported (CC BY-SA 3.0)
You are free to:
Share — copy and redistribute the material in any medium or format
Adapt — remix, transform, and build upon the material
for any purpose, even commercially.

If anyone does make this, or improves on the code or anything then please do let me know! So, have at it!

Cheers,

Simon.

ETA: I forgot to mention that this can be used with any Geiger counter that spits out the CPM over RS232, such as the counters to connect to Radlog.
AETA: I also forgot to mention that some of the code is a little clumsy and probably not very efficient, especially the LED part for changing the colour etc, but that said it does seem to run well on the Pro-mini.

Well done! Looks great, love the homebrew board on the bottom,

Thank you for sharing!

No problem at all, very happy to share, and thanks for your comment.

I should note though that my project is only the homebrew board. It is designed to connect up to any counter that gives CPM via RS232 and gives that counter logging and GPS capability so in theory it should be compatible with any counter that gives CPM via RS232.

I have sorted the battery issue by adding a couple of 18650 Lipo's and a buck converter to regulate the voltage to 5.0V. That seems to be holding up well. The entire unit (logger and counter) consume about 10ma at 20CPM background radiation so roughly working out if my batteries are 2000mAh (they state 2600mAh but I doubt I will get that) and the unit uses 10mA then it should last for around 200 hours! I just need to sort a charging circuit now to charge the batteries when the unit is powered from 12v from the car, or mains adapter.

I went out for a quick test with it and it seems to be OK except for sketchy GPS data. I think I need to improve the GPS antenna, so adding an external antenna should sort that. I have a Peugeot car with heat reflective windscreen and it plays havok with most cheaper GPS receivers. At least I'm hoping that is the issue!

Here is the data for anyone interested and a quick picture of what it looks like so far:
https://www.google.com/maps/d/viewer?mid=zasLAdbQXqtw.kxVyakPPw-s0



Cheers!

After some more testing and investigation I found the issue in sketchy GPS was actually the code. I've fixed it and the results are much, much better. There is just one tiny issue now where the CPM being read from the counter is recorded occasionally with an extra digit or two counts on one record. I reckon once that is sorted I can call it version 1.0

I have updated the download link with the latest code. Here are the results so far:

https://www.google.com/maps/d/edit?mid=zasLAdbQXqtw.kInoUYbBsJO8&usp=sharing

Looks great! Working well.

I have been meaning to add 'journeys' to radmon.org. At the moment the marker is just updated with the last GPS coords if used. I need to add a function to expand the data table with two more columns and log the GPS coords. That shouldn't be difficult.

I've been wondering how to handle 'journeys' when displaying the map. Probably the best way is to have 'journeys' visible on the userpage. That means specifying a start and an end, perhaps the most user friendly way would be to detect start and end points on the server during data submission, i.e. when the coordinates change. And maintain a list of detected journeys.