Geiger Counter

[FotoFieber]

As I live near a nuclear power plant, I thought it would be a good idea to have a radioactivity sensor:

Components used:

Geiger Counter Kit:
http://www.ebay.com/itm/321499888801?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

An SBM-20 tube:
http://www.ebay.com/itm/280865770387?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

And MySensors with this sketch:

#include <SPI.h>
#include <MySensor.h>

#define DIGITAL_INPUT_SENSOR 3   // The digital input you attached your motion sensor.  (Only 2 and 3 generates interrupt!)
#define INTERRUPT DIGITAL_INPUT_SENSOR-2 // Usually the interrupt = pin -2 (on uno/nano anyway)
#define CHILD_ID 1   // Id of the sensor child

#define LOG_PERIOD 60000     //Logging period in milliseconds, recommended value 15000-60000.

#define MAX_PERIOD 60000    //Maximum logging period

unsigned long counts;             //variable for GM Tube events

unsigned long cpm;                 //variable for CPM

unsigned int multiplier;             //variable for calculation CPM in this sketch

unsigned long previousMillis;      //variable for time measurement

unsigned long timeReceived = 0;
unsigned long timeRequested = 0;

MySensor gw;
// Initialize motion message
MyMessage msg(CHILD_ID, V_VAR1);

void setup()
{
  wdt_enable(WDTO_8S);
  gw.begin();

  // Send the sketch version information to the gateway and Controller
  gw.sendSketchInfo("Geiger Sensor", "1.1");

  wdt_reset();
  // Register all sensors to gw (they will be created as child devices)
  gw.present(CHILD_ID, S_ARDUINO_NODE);
  
  // Geiger initialise
  counts = 0;

  cpm = 0;

  multiplier = MAX_PERIOD / LOG_PERIOD;      //calculating multiplier, depend on your log period

  pinMode(DIGITAL_INPUT_SENSOR, INPUT);      // sets the geiger sensor digital pin as input

  digitalWrite(DIGITAL_INPUT_SENSOR, HIGH);                                 // turn on internal pullup resistors, solder C-INT on the PCB

  attachInterrupt(1, tube_impulse, FALLING);  //define external interrupts

}

void loop()
{ 
  wdt_reset();
  unsigned long currentMillis = millis();

  if (currentMillis - previousMillis >= LOG_PERIOD) {

    cpm = counts * multiplier;

    gw.send(msg.set(cpm));

    counts = 0;
    previousMillis = currentMillis;

  }
}


void tube_impulse() {              //procedure for capturing events from Geiger Kit

  counts++;

}

I get cpm and in Node-Red I calculate microsievert/per hour:

[{"id":"ba386057.845d3","type":"mqtt-broker","broker":"192.168.92.4","port":"1883","clientid":"NodeRed"},{"id":"75acf1fb.8a531","type":"mqtt in","name":"Geiger CPM","topic":"MyMQTT/48/1/V_VAR1","broker":"ba386057.845d3","x":146,"y":52,"z":"d1478aa9.2eb878","wires":[["d17bbe2a.2e844"]]},{"id":"d17bbe2a.2e844","type":"function","name":"Nach uSievert umrechnen","func":"cpm = msg.payload;\n\n// für SBM 20 Röhre\n// http://cs.stanford.edu/people/nick/geiger/\nusv = cpm * 0.0057;\n\nmsg.topic = 'NodeRed/Geiger/usv';\nmsg.payload = usv;\n\nreturn msg;","outputs":1,"valid":true,"x":377,"y":52,"z":"d1478aa9.2eb878","wires":[["c53927ba.3ac6d8"]]},{"id":"c53927ba.3ac6d8","type":"mqtt out","name":"","topic":"","qos":"","retain":"","broker":"ba386057.845d3","x":647,"y":52,"z":"d1478aa9.2eb878","wires":[]}]```

[hek]

Cool! I also live near a plant but it has been closed for 10+ years unfortunately (?).

[Sparkman]

@FotoFieber Thanks for posting. I have this Geiger counter kit on its way to me: https://sites.google.com/site/diygeigercounter/software-features along with an sbm-20. I plan to build the outside sending unit like this: https://sites.google.com/site/diygeigercounter/wireless-monitoring along with a custom shield that'll hold the NRF24 with PA/LNA and a few other components to control the power to the geiger counter and the NRF24. I won't need the indoor display station that's described on the site as I'm using the MySensors gateway and HomeSeer instead.

Cheers
Al

[FotoFieber]

Here is the update for mysensors 2.0

//
#define SKETCH_NAME "Geiger Sensor"
#define SKETCH_MAJOR_VER "2"
#define SKETCH_MINOR_VER "0"

// Enable and select radio type attached
#define MY_RADIO_NRF24

#define MY_RF24_CHANNEL  13
#define MY_RF24_BASE_RADIO_ID ((uint64_t)0xF8A813FC09CL)


//
#define DIGITAL_INPUT_SENSOR 3   // The digital input you attached your motion sensor.  (Only 2 and 3 generates interrupt!)
#define INTERRUPT DIGITAL_INPUT_SENSOR-2 // Usually the interrupt = pin -2 (on uno/nano anyway)
#define CHILD_ID 1   // Id of the sensor child

#define LOG_PERIOD 60000     //Logging period in milliseconds, recommended value 15000-60000.

#define MAX_PERIOD 60000    //Maximum logging period

unsigned long counts;             //variable for GM Tube events

unsigned long cpm;                 //variable for CPM

unsigned int multiplier;             //variable for calculation CPM in this sketch

unsigned long previousMillis;      //variable for time measurement

unsigned long timeReceived = 0;
unsigned long timeRequested = 0;

// Enable debug prints to serial monitor
#define MY_DEBUG


#include <SPI.h>
#include <MySensors.h>

MyMessage msg(CHILD_ID, V_VAR1);

void setup()
{
  wdt_enable(WDTO_8S);
  
  // Geiger initialise
  counts = 0;

  cpm = 0;

  multiplier = MAX_PERIOD / LOG_PERIOD;      //calculating multiplier, depend on your log period

  pinMode(DIGITAL_INPUT_SENSOR, INPUT);      // sets the geiger sensor digital pin as input

  digitalWrite(DIGITAL_INPUT_SENSOR, HIGH);                                 // turn on internal pullup resistors, solder C-INT on the PCB

  attachInterrupt(1, tube_impulse, FALLING);  //define external interrupts

  wdt_reset();
}

void presentation() {
  // Send the sketch version information to the gateway and Controller
  sendSketchInfo(SKETCH_NAME, SKETCH_MAJOR_VER "." SKETCH_MINOR_VER);

  wdt_reset();
  wait(500);
  present(CHILD_ID, S_ARDUINO_NODE);
  
  wdt_reset();
  wait(500);
 }

void loop()
{ 
  wdt_reset();
  unsigned long currentMillis = millis();

  if (currentMillis - previousMillis >= LOG_PERIOD) {

    cpm = counts * multiplier;

    send(msg.set(cpm));

    counts = 0;
    previousMillis = currentMillis;

  }
}


void tube_impulse() {              //procedure for capturing events from Geiger Kit

  counts++;

}

@Hek
What do you think about a sensor type geiger counter with cpm and microsievert? V_VAR1 for cpm ist not cool

[hek]

Haha, not cool. What? Radioactivity is always cool!

Well, we still use VAR_1 for pulses in EnergyMeterPulseSensor, which probably is a bit more commonly used. A generic V_PULSECOUNT perhaps..On the EnergyMeterPulseSensor is it only used for saving a state in case of power failure. Is it the same use-case here?

[FotoFieber]

@hek
counts per minute:
https://en.wikipedia.org/wiki/Counts_per_minute

A generic V_PULSECOUNT would be fine.

The microsievert is the interesting physical unit you can derive from the cpm. The calculation is depending from the tube you use.

http://cs.stanford.edu/people/nick/geiger/

In my case:
usv = cpm * 0.0057;

What about a type S_RADIOACTIVITY?

Here the natural radioactivity in my garage:

The sum of the doses you get over time is the interesting number:
https://en.wikipedia.org/wiki/Sievert

[hek]

S_RADIOACTIVITY sounds like useful new device type.

When reading up a bit more. Wouldn't it be better to send in radiation level (uSv/hr) as V_LEVEL. We try to re-use V_LEVEL between device-types for SI-levels of any kind.

I have started this a new issue here to discuss it further:
https://github.com/mysensors/MySensors/issues/567

[alexsh1]

Excellent - thank you guys. I have been looking for an addition to my weather station.
I think I'll place an order for this one: http://www.ebay.co.uk/itm/182166337823?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT
This is 100% Japanese built Arduino based Geiger counter.

[alexsh1]

@hek Henrik, where do you stand with S_RADIOACTIVITY please?
Unfortunately, I cannot use S_CUSTOM or any other with Domoticz so has to wait for a S_RADIOACTIVITY being implemented with (1) MySensors (2) Domoticz.

Thanks
Alex

[hek]

It's just a matter on agreeing on what types/data to send. Please post your input in the issue.

[alexsh1]

@hek The logging software is reporting is as follows every minute:

CPS, 2, CPM, 15, uSv/hr, 0.08, SLOW
(Please see http://mightyohm.com/blog/2012/02/tutorial-geiger-counter-data-logging/)

Therefore, there are four parameters here and I propose to use the following:

1. CPS --> ???
2. CPM --> ???
3. uSv/hr --> S_RADIOACTIVITY (V_LEVEL)
4. SLOW/FAST -> S_INFO (V_TEXT)

[alexsh1]

We can keep it simple - CPM and uSv/hr are the two typically reported.
Even more simple - knowing CPM we can figure out uSv/hr

[FotoFieber]

@alexsh1
Calculation of uSv/hr based on CPM is dependent of the tube. If we do not implement the calculation in the sketch, it must be done in the controller.

[alexsh1]

@FotoFieber my understanding is that all meters are calibrated to either Cs137 or Co60, which is more likely down to the tube. However, I do not understand why we care about the conversion. My geiger meter reports both uSv/hr and CPM and a number of other meters reports exactly the same. If there is any conversion required, it has to be done in the sketch IMHO.

[alexsh1]

@hek Any news on this please? I am missing definition for CPS/CPM.

[alexsh1]

@FotoFieber Cannot use MyMessage msg(CHILD_ID, V_VAR1); as this is not supported by Domoticz.