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µRadMonitor RRDTool Graphing

I’ve been meaning to sort some local graphs out for a while for the radiation monitor, and I found a couple of scripts created by a couple of people over at the uRadMonitor forums for doing exactly this with RRDTool.

µRadLogger
µRadLogger

Using another Raspberry Pi I had lying around, I’ve implemented these scripts on a minimal Raspbian install, and with a couple of small modifications, the scripts upload the resulting graphs to the blog’s webserver via FTP every minute.

#!/bin/sh

URL=http://192.168.1.4/j
rrdpath="/usr/local/bin"

jsondata=$( curl -s $URL);

v_cpm=$( echo $jsondata | cut -f 4 -d "," | cut -f 2  -d ":" )
v_temp=$( echo $jsondata | cut -f 5 -d "," | cut -f 2  -d ":" )

echo CPM : $v_cpm
echo Temperature : $v_temp

This script just grabs the current readings from the monitor, requiring access to it’s IP address for this.

#!/bin/sh

rrdpath="/usr/bin"
rrddata="/usr/local/urad/data"
rrdgraph="/usr/local/urad/graph"

mkdir $rrddata
mkdir $rrdgraph

   $rrdpath/rrdtool create $rrddata/uRadMonitor.rrd -s 60 \
            DS:cpm:GAUGE:300:0:U   \
            DS:temp:GAUGE:300:-100:100  \
            RRA:AVERAGE:0.5:1:600  \
            RRA:AVERAGE:0.5:6:700  \
            RRA:AVERAGE:0.5:24:775 \
            RRA:AVERAGE:0.5:288:797 \
            RRA:MAX:0.5:1:600 \
            RRA:MAX:0.5:6:700 \
            RRA:MAX:0.5:24:775 \
            RRA:MAX:0.5:288:797
   echo database $rrddata/uRadMonitor.rrd created.

This script sets up the RRDTool data files & directories.

#!/bin/sh

URL=http://192.168.1.4/j
rrdpath="/usr/bin"
rrddata="/usr/local/urad/data"
rrdgraph="/usr/local/urad/graph"
rrdfmt="--font AXIS:6: --font TITLE:9: --font UNIT:7: --font LEGEND:7: --font-render-mode mono --color ARROW#000000 --color GRID#8C8C8C --color MGRID#000000 -v \"cpm\" --alt-y-mrtg --width 600"

jsondata=$( curl -s $URL );

v_cpm=$( echo $jsondata | cut -f 4 -d "," | cut -f 2  -d ":" )
v_temp=$( echo $jsondata | cut -f 5 -d "," | cut -f 2  -d ":" )

echo CPM : $v_cpm
echo Temperature : $v_temp


$rrdpath/rrdtool update $rrddata/uRadMonitor.rrd N:$v_cpm:$v_temp


$rrdpath/rrdtool graph --imgformat PNG $rrdgraph/rad-day.png   --start -86400 --end -600 --title "Radiation daily" $rrdfmt \
        DEF:cpm=$rrddata/uRadMonitor.rrd:cpm:AVERAGE \
                AREA:cpm#00CCCC:"Counts Per Minute\g" \
                        GPRINT:cpm:MAX:"  Max \: %5.1lf " \
                        GPRINT:cpm:AVERAGE:" Avg \: %5.1lf " \
                        GPRINT:cpm:LAST:" Last \: %5.1lf \l"

$rrdpath/rrdtool graph --imgformat PNG $rrdgraph/rad-week.png  --start -604800   -z    --title "Radiation weekly" $rrdfmt \
        DEF:cpm=$rrddata/uRadMonitor.rrd:cpm:AVERAGE \
                AREA:cpm#00CCCC:"Counts Per Minute\g" \
                        GPRINT:cpm:MAX:"  Max \: %5.1lf " \
                        GPRINT:cpm:AVERAGE:" Avg \: %5.1lf " \
                        GPRINT:cpm:LAST:" Last \: %5.1lf \l"

$rrdpath/rrdtool graph --imgformat PNG $rrdgraph/rad-month.png --start -2592000  -z    --title "Radiation monthly" $rrdfmt \
        DEF:cpm=$rrddata/uRadMonitor.rrd:cpm:AVERAGE \
                AREA:cpm#00CCCC:"Counts Per Minute\g" \
                        GPRINT:cpm:MAX:"  Max \: %5.1lf " \
                        GPRINT:cpm:AVERAGE:" Avg \: %5.1lf " \
                        GPRINT:cpm:LAST:" Last \: %5.1lf \l"

$rrdpath/rrdtool graph --imgformat PNG $rrdgraph/rad-year.png  --start -31536000 -z    --title "Radiation yearly" $rrdfmt \
        DEF:cpm=$rrddata/uRadMonitor.rrd:cpm:AVERAGE \
                AREA:cpm#00CCCC:"Counts Per Minute\g" \
                        GPRINT:cpm:MAX:"  Max \: %5.1lf " \
                        GPRINT:cpm:AVERAGE:" Avg \: %5.1lf " \
                        GPRINT:cpm:LAST:" Last \: %5.1lf \l"

$rrdpath/rrdtool graph --imgformat PNG $rrdgraph/rad-decade.png  --start -315360000 -z    --title "Radiation decadely" $rrdfmt \
        DEF:cpm=$rrddata/uRadMonitor.rrd:cpm:AVERAGE \
                AREA:cpm#00CCCC:"Counts Per Minute\g" \
                        GPRINT:cpm:MAX:"  Max \: %5.1lf " \
                        GPRINT:cpm:AVERAGE:" Avg \: %5.1lf " \
                        GPRINT:cpm:LAST:" Last \: %5.1lf \l"
ncftpput -R -v -u "<FTP_USER>" -p "<FTP_PASSWORD>" <FTP_HOST> <FTP_REMOTE_DIR> /usr/local/urad/graph/*

The final script here does all the data collection from the monitor, updates the RRDTool data & runs the graph update. This runs from cron every minute.
I have added the command to automate FTP upload when it finishes with the graph generation.

This is going to be mounted next to the monitor itself, running from the same supply.

The Graphs are available over at this page.

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uRadMonitor Network

I’ve joined the uRadMonitor network! I’m told my unit is on the way & it should be going live here in Manchester, UK within about 10 days.

uRadMonitor Unit
uRadMonitor Unit

This is a crowd project to monitor background radiation levels all over the world, so far there’s a lot of units already online.

More to come once my unit arrives!

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Kidde Smoke Alarm

Top
Top

Old type ionization smoke alarm. Top of the device with the test button & sounder.

Bottom
Bottom

Bottom of the device. Battery compartment in centre.

PCB
PCB

Internals of the smoke alarm. Main component visible is the Ionization chamber.

Sounder
Sounder

Piezo sounder on inside of the top.

Ionization Chamber
Ionization Chamber

Inside the Ionization Chamber. 1µCi Americium-241 alpha particle source in the centre.
The radiation passes through the chamber, between the pair of electrodes, ionizing the air & permitting a small current to pass between the electrodes.
Any smoke that enters the chamber absorbs the alpha particles, which reduces the ionization and interrupts this current, setting off the alarm.

Controller
Controller

Controller IC beneath the chamber.