Sensors
sensors

Relatively inexpensive, transportable and deployable sensors are produced all over the world for a variety of analytes. Broadly defined, sensors respond to a physical or chemical property, providing an interpretable output. For our purposes, a main distinction of a sensor versus a sampler is that sensors do not require laboratory-based analyses, and provide outputs in near-real time. Though we often think of sensors as part of the electronics field, plenty of analog sensors have been available for decades. Common analog sensors include things like mercury thermometers and classic barometers. Common digital sensors include things like voltmeters. In Public Lab, we're interested in a broad variety of sensors, both analog and digital, designed for measuring chemical and physical properties in air or water. ###Air Sensors There are a ton of different air sensors on the market these days, with common analytes including carbon monoxide (e.g. smoke detectors), temperature, humidity, particulate matter, and more. Some of these sensors require a digital interface with a controller and data logger, others are analog. Please see more information [here](/wiki/air-sensors) and check out air sensors in the table below. Please add more sensors that you've used! [embed table] ###Water Sensors Water sensors are available for several analytes, such as salinity, pH, and depth. Like air sensors, water sensors may be digital or analog. Any digital water sensors that are meant to be deployed will require water-tight enclosures for the electronic components. Please see more information [here](/wiki/water-sensors), and check out and add more sensors to the table below. [embed table]...


Author Comment Last activity Moderation
warren "Indeed -- maybe it could either just say "not safari or iOS" as https://spectralworkbench.org/capture does, or could specifically return an error a..." | Read more » over 8 years ago
dusjagr "Very nice! we have experimented with the same softModem library on the attiny85 for the same reason of an ultra cheap communication to send data to..." | Read more » over 8 years ago
rmeister "Hi Liz, thanks for your feedback! You can click on the photo to get a larger version. There the connections are visible more clearly. I'll see if I..." | Read more » over 8 years ago
rmeister "Oh, maybe I should add a note for iPhone and Mac users. According to this site, Safari does not support WebRTC yet: http://iswebrtcreadyyet.com/ " | Read more » over 8 years ago
warren "Huh, it's weird, but I could have sworn I clicked a link earlier and got http. But it seems fine now. I wonder what happened. Note to future selve..." | Read more » over 8 years ago
rmeister "Is there somewhere a link without https? " | Read more » over 8 years ago
rmeister "Cool, thanks for your results! Chrome Android → Chrome Android did work for me, but not very well. Sometimes I had to repeat sending like 10 times..." | Read more » over 8 years ago
warren "Oh, also -- for the WebRTC to work, you need to link to the https version of the Github Pages site -- because that's now required for audio access ..." | Read more » over 8 years ago
warren "I'm curious about the browser-to-browser use case, because as a SoftModem compatible protocol, we could also make this available as a general purpo..." | Read more » over 8 years ago
liz "Hi Richard, These are great instructions! I don't have experience to read the wiring diagram, and can't tell from the photo exactly what the signif..." | Read more » over 8 years ago
warren "I'm hoping to test with an Arduino soon too, but as a first attempt I was able to get "Hello world!" to transmit from my phone to my laptop with no..." | Read more » over 8 years ago
kinasmith "I am also very curious how much temperature affects the batteries in very low current applications. I haven't found good documentation about that. ..." | Read more » over 8 years ago
cfastie "This is probably not the best data set to do calculus on. The air temperature data is from a sensor in a jug suspended above the pile, and the batt..." | Read more » over 8 years ago
donblair "Yay, data!! Neat observation about the battery voltage and the temperature. Makes me want to compare the rate of battery voltage drop to the temp..." | Read more » over 8 years ago
kinasmith "Nicely done, and nice temps for such a small pile too! I'm curious to see how long they can sustain that heat. I've done some work with compost in ..." | Read more » over 8 years ago
david-days "I imagine so (regarding the grass). If it's fairly fresh, there's probably enough water content to feed the bacteria as things break down. We use..." | Read more » over 8 years ago
cfastie "Thanks David, I wish I had some of your manures to spice up my pile. I'm surprised at how hot this pile is without the addition of any N-rich mater..." | Read more » over 8 years ago
david-days "Excellent work, @cfastie! I live on a farm in Ohio, and we use cleanup from the chicken house and the horse/goat barns to make our compost piles. ..." | Read more » over 8 years ago
cfastie " I kinda like the switch on the Riffle and now I know that it is something to pay more attention to. But I guess it adds much more complexity that ..." | Read more » over 8 years ago
donblair "Chris, This is such a beautiful project! The lapse rate calculation is so fun to see. Quick reactions: That power switch goof is annoying. I w..." | Read more » over 8 years ago
ggallant "D5 appears to connect the INT/SQW on the RTC to PD5 on the CPU. I would be very interested in how one uses the feature. I'm assuming that it requir..." | Read more » over 8 years ago
mathew "The RTC can be set to shutdown and wake the AT328P, it just uses another pin that could be used for a sensor. @donblair left an exposed pin availa..." | Read more » over 8 years ago
ggallant "Chris, I really don't know the actual time but assuming 800usec (nice for the math) to sleep and wake up it would be 800 / 8,000,000 or 0.01% whi..." | Read more » over 8 years ago
cfastie "George that's a good point. Although the real time clock is running all the time, it is not smart enough to do something as complicated as setting ..." | Read more » over 8 years ago