I suggested that last idea at a previous company I worked for, doing temperature monitoring. The owner loved it, and thought it would make a ton of money for us.<div><br></div><div>And then did nothing with it.</div><div>
<br clear="all"><span style="font-family:arial,sans-serif;font-size:13px"><b><b><div><span style="font-weight:normal"><b><b><span style="font-weight:normal"><span style="font-size:x-small">Drew Van Zandt</span></span></b></b></span></div>
<div><span style="font-weight:normal"><b><b><span style="font-weight:normal"><span style="font-size:x-small"><span style="font-family:arial">Artisan's Asylum Craft Lead, Electronics & Robotics</span><br>Cam # US2010035593 (</span></span></b></b><span style="font-weight:normal"><span style="font-size:x-small">M:</span></span><b><b><span style="font-weight:normal"><span style="font-size:x-small">Liam Hopkins </span></span></b></b><span style="font-weight:normal"><span style="font-size:x-small">R:</span></span><b><b><span style="font-weight:normal"><span style="font-size:x-small"> Bastian Rotgeld)<br>
</span></span></b></b></span><span style="font-family:arial,sans-serif;font-size:13px"><b><b><span style="font-weight:normal"><b><b><span style="font-weight:normal"><span style="font-size:x-small">Domain Coordinator, MA-003-D. Masquerade aVST </span></span></b></b></span></b></b></span><br>
</div></b></b></span><font size="1"><br></font><br>
<br><br><div class="gmail_quote">On Tue, Mar 13, 2012 at 2:32 AM, Tom Metro <span dir="ltr"><<a href="mailto:tmetro%2Bhhacking@gmail.com">tmetro+hhacking@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
Thermal flashlight 'paints' cold rooms with colour<br>
<a href="http://www.newscientist.com/article/mg21328546.200" target="_blank">http://www.newscientist.com/article/mg21328546.200</a><br>
<br>
The device comes from the Public Laboratory for Open Technology and<br>
Science, a non-profit group based in Cambridge, Massachusetts, that<br>
develops open-source tools to allow ordinary people to investigate<br>
environmental issues.<br>
...<br>
Standard thermal cameras are prohibitively expensive for ordinary<br>
people.<br>
<br>
Right, a Fluke Thermal Imager, for example, will set you back $2000 ~ $3000.<br>
<br>
<br>
In contrast, the thermal flashlight prototype costs about $40. What's<br>
more, it can easily be assembled by someone with no electronics<br>
expertise.<br>
...<br>
The thermal flashlight is built around a single infrared thermometer.<br>
This scans an area of wall and picks up varying levels of radiation<br>
emanating from it. This temperature information is fed into a<br>
microprocessor, which controls a multicoloured LED light. Shine the<br>
flashlight against a surface and the colour shows you a real-time<br>
temperature reading. Areas of the wall with a cooler temperature show<br>
up blue, while red light shines on patches that register as warmer.<br>
<br>
Even easier, you can buy one for $24:<br>
<a href="http://www.amazon.com/Black-Decker-TLD100-Thermal-Detector/dp/B001LMTW2S/" target="_blank">http://www.amazon.com/Black-Decker-TLD100-Thermal-Detector/dp/B001LMTW2S/</a><br>
<br>
I bought one of these a couple of years ago when they cost $50. It's<br>
essentially a run-of-the-mill non-contact IR thermometer, with a slight<br>
twist. They stick a multi-color LED on it that lights up the target area<br>
with green, red, or blue light depending on whether the current spot you<br>
are pointing at is warmer or colder than your starting point. (I forget<br>
some of the details, like whether the color change is relative (I think)<br>
or tied to a fixed absolute temperature. And whether it is continuously<br>
variable (intensity) from red to green to blue, or if flips from one<br>
color to the next when a threshold is tripped (product description and<br>
my vague recollection supports the latter).)<br>
<br>
My first thought when getting this device was how one might hack it to<br>
emulate an expensive thermal imager. The initial thought was that you'd<br>
stick it on a tripod, mounted to a computer controlled pan/tilt security<br>
camera mount. Then a computer could make it raster scan a wall. How<br>
you'd capture the color information eluded me.<br>
<br>
<br>
An image of the light-painted room showing exactly where heat is<br>
leaking can then be captured using a webcam with an online app called<br>
Glowdoodle or just standard time-lapse photography.<br>
<br>
Ah! Glowdoodle (<a href="http://scripts.mit.edu/~eric_r/glowdoodle/" target="_blank">http://scripts.mit.edu/~eric_r/glowdoodle/</a>) is the<br>
missing piece. Looks like you need to use it in a fairly darkened room,<br>
which also would work for an old-school solution using a 35mm analog<br>
camera with the shutter held open.<br>
<br>
To really emulate an IR imager the Black and Decker thermometer wouldn't<br>
cut it. The wall would appear in only 3 color, and no varying shades.<br>
This is perhaps where the D-I-Y thermometer is superior.<br>
<br>
I think the B&D thermometer also has a laser pointer to help you aim (as<br>
is common for IR thermometers), and I don't recall if you can turn the<br>
laser off. That bright red dot would mess up your captured heat map.<br>
<br>
One of the sales claims for the B&D was "Helps homeowners track down<br>
power-draining drafts." Before buying I was skeptical how it could do<br>
that. After buying it became apparent that they were stretching the<br>
truth and not directly detecting drafts, but just temperature variations<br>
that are often affiliated with drafts. There are tools that can actually<br>
detect drafts, but this isn't it.<br>
<br>
In any case, after playing around with it for a while, I lost enthusiasm<br>
for the tool and never did really make use of it. (I was really far more<br>
interested in detecting actual drafts than measuring insulation quality;<br>
on a first pass for weatherization, you have a far higher impact by<br>
stopping air leaks than by improving insulation.) I should dust it off<br>
and do something with it.<br>
<br>
The real question is why hasn't some manufacturer created a low-end<br>
thermal imager that employs this technique. There are no recent<br>
developments that have just made it possible. All the tech involved was<br>
pretty much available a decade ago.<br>
<br>
For example, you create a tool a bit larger than an IR thermometer,<br>
stick a cheap CCD camera into it, and a motorized mirror assembly in<br>
front of the IR sensor so it can scan the field of view. Stick in a<br>
micro to drive the scanner and composite the thermal data over the<br>
video. Add on an LCD for aiming and image preview, plus an SD card and<br>
USB port to get the images out of it. Presto, thermal imager for under<br>
$300. It'd be slow. You'd have to stick it on a tripod. Pros wouldn't<br>
want it, but you might sell enough to non-profit energy conservation<br>
groups and early adopters to get the price under $200, at which point<br>
you'd interest homeowners.<br>
<br>
-Tom<br>
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</blockquote></div><br></div>