We've relaunched the newsletter and will be sending it out monthly, in addition to sharing it on...
|Thermal photography||over 1 year ago by Sara||66||94,163||9|
|Posters||over 2 years ago by Sara||31||8,291||7|
|Scanning thermal camera||about 3 years ago by warren||3||27,088||1|
|Thermal Fishing Bob: PLOTS Boston Toolshed Raising||about 3 years ago by Sara||9||3,900||0|
|May 26th AS220 Thermal Flashlight Workshop||over 4 years ago by Sara||5||3,877||0|
Thermal imaging can be used to document heat/AC leaks from insulation gaps on a building's facade, reveal warmer ground water inflows (either fresh or chemical-laden) or "thermal pollution" from industrial processes entering ocean-temperature waterbodies, as well as identify areas on the human body experiencing infection or stress (includes epidemiological applications).
Community applications so far include both a "heat-busters" program in East Harlem and a "forensic" water quality monitoring program in the Gowanus Canal.
There are three prototypes in development:
"FLIR" cameras can produce images such as the one below, and are typically used to identify heat leaks, but even low-resolution FLIR cameras can cost thousands of dollars. Our goal is to make this kind of investigation (and the potential savings) cheap, easy, fun, and informative for those of us without $10k in our pockets.
The first approach results in a kind of "light painting" -- a color heatmap overlaid directly onto the scene. This is the simplest, cheapest, and to date, most effective way we have developed of measuring heat leaks or cool leaks indoors and outdoors. Simply put, the "flashlight" puts out red light if it's pointed at something hot (default 75 deg F or more) and blue light if it's pointed at something cold *(default 60 deg F or less):
To capture the light painting over time, we have been using timelapse photography or the prototype Public Lab Thermographer website (or its inspiration, GlowDoodle), as seen in the top image on this page.
Parts list For a Thermal Flashlight with 3.6 V Melexis Sensor and Common Anode LED.
_Note: The goal of this file is to be a place to download everything without pursuing other links. If there are changes or updates please feel free to add and re-upload. If the file is missing anything, please comment below. You might notice that this is for the 5v Melexis, but it will work for either without issues.
Alternative variations of the Flashlight can be made with a 5.5V Melexis Sensor and Common Cathode LED. For the 5.5 V sensor follow this diagram: http://publiclaboratory.org/notes/sara/2-7-2012/circuit-diagram-5v-melexis-sensor For the common cathode circuit board follow this diagram: http://publiclaboratory.org/notes/warren/2-11-2012/common-cathode-variant-thermal-flashlight-code
Links to purchasing equipment:
If you are starting an electronics kit from scratch:
These research notes will be integrated into this page to provide instructions on building and using your own thermal flashlight:
Several meetups have been organized to build and test thermal flashlights, at RISD (Providence, RI) and in Brooklyn, NY. We are organizing one now in Somerville, MA:
The fishing bob is designed simply enough that anyone can build it and its components can be easily obtained from Home Depot and Radio Shack.
To produce a cheaply made, easy to use piece of technology to track temperature changes in water. And to produce a product that can be easily altered to suit many innovative needs.
First iteration of the Thermal Fishing Bob developed in Sara Wylie’s class at RISD: http://publiclab.org/wiki/thermal-fishing-bob
Second iteration of the Thermal Fishing Bob developed at 2014 Barnraising: http://www.publiclab.org/wiki/thermal-fishing-bob-barnraising http://www.publiclab.org/wiki/thermal-fishing-bob-plots-boston-toolshed-raising
First long exposure pictures with the fishing bob: http://publiclab.org/wiki/thermal-fishing-bob-plots-boston-toolshed-raising http://publiclab.org/notes/Sara/04-23-2014/successful-thermal-fishing-bob-maps
The fishing bob’s tech is sealed within a waterproofed translucent container, a Koolaid mix container will do, with only the thermistor poking out the bottom (sealed around the edges with hot glue). The fishing bob is then wrapped in foam so that it floats, attached to a reel so it can be pulled, and dropped in the water. The thermistor reads changes in temperature and the LED within the fishing bob causes the fishing bob to change color in accordance with the temperature. The readings are recorded on the Arduino inside, which can then be read once it is plugged into a computer.
While the fishing bob is being dragged across the water long exposure photos are being taken to create a “light painting” of the temperature gradient. One neat way to make these long exposure images is to use glowdoodle from MIT.
I am currently working with Sara Wylie on a project to make the thermal fishing bob towable behind a kayak. In previous testing the fishing bobs tended to submerge and become water damaged so we are working on a prototype that would be set into a floatation device. One concept is to wrap two fishing bobs in foam and set them into the legholes of a child’s floatie, duct taping them into place. The first test was successful, the fishing bobs stayed in place above the water and there was no noticeable water damage. A second idea is to attach three fishing bobs to a foam sled/boogie board with thermistors of differing lengths to take a 3D image of the thermal gradient. This idea has yet to be tested. A third idea is to utilize ideas from the coqui to transform the thermal fishing bob into a conductivity fishing bob. This idea is still in the brainstorming stage, but we will be building a prototype soon.
Thermal plume along the Charles River
Fishing bob made at MIT workshop from a soda cup
Thermal fishing bob circuit
Fishing bobs ready to go
Fishing bob being lowered into the river
First prototype of towable fishing bob