Temperature-sensing stirbar with RFID
github.com
github.com
I formed a company and got $50k in grant money from the state of Wisconsin along with incubator space and advisors. I did all the initial software and hardware development, the first one I built took components from a battery powered toothbrush to inductively charge so I didn’t need a charging port exposed to solutions.
I loved working on this project, I had the idea after having frustrating experiences working with 30 year old lab equipment that took up more bench space in the lab than my backpack did. At the end of the day that’s all it was. I had no idea wtf I was doing and the company eventually folded as real life became too much to juggle with my project. I figured I could use the same form factor to build tons of different sensors based on the many different ion selective electrodes already on the market. Eventually I needed to try and manufacture these sensors myself in a form factor that would fit inside flasks in the lab.
Letting this project fall by the wayside is probably the single greatest regret of my life. I often think back about how different things could’ve turned out if only I had made the correct decisions and executed properly and actually found someone to license my patent… so it goes.
https://m.youtube.com/watch?v=RrBhliK1ryY&pp=ygUbUGhpbmRpbmc...
Ben, West & I worked on this project in 2014. We filed a provisional patent as well, reached out to potential licensees, and had a handful that wanted to pull the trigger to turn it into a functioning product. E.g. here was the sell sheet [1].
Unfortunately, our "day jobs" at Google[x] got in the way -- they weren't particularly keen to have researchers pursuing side gigs, even if Google had no interest in pursuing it themselves & the IP was cleanly produced externally. They refused to sign off on a clean IP waiver, so the licensing discussions fell apart.
At the end of the day: It was a good, viable idea that we wanted to exist. Never anticipated that it would be all that lucrative -- the volume & profit margins were likely low.
[1] https://drive.google.com/file/d/1mRiIHnrATd2dEzC2xSpM8_Mx1kG...
yet another confirmation google has become massive corporation where innovation goes to die
You guys were smart and went RFID (I went Bluetooth) which means you skip the whole battery and battery charging steps and also avoiding another flaw of my design which was it’s narrow working temperature range. Turns out sticking a lipo battery in a flask of boiling water isn’t exactly a good idea lol. It also gives you another product to offer as an “RFID enabled hot plate” as opposed to just working in existing hot plates. Temperature of solution is an important variable to determining an accurate pH reading so temp was more of an incidental feature for me.
My vision was having a whole tray of these stir bars: one for pH, one for nitriles, one for nitrates, etc. anything that already had an ion selective electrode that was capable of measuring concentration would, in theory, just plug right in to that form factor. Ion selective electrodes are essentially just tiny batteries whose output voltage varies proportionately to the concentration of the ion on the outside of the glass. They’re super cool pieces of hardware just by themselves.
I was a student at a local community college at the time working on my liberal arts degree and guaranteed transfer to a state school. It makes me wonder how many others in the world might have a working prototype stuffed in their closet too :)
It sucks Google killed it for you, I thought my little community college might try and come after me for similar claims if I used any of their facilities of faculty to help with the development so I avoided the place like the plague while working on it to minimize my perceived risk. I can’t imagine my level of paranoia if it woulda been Google.
If you ever want to reach out and commiserate about working on this project I’d love to hear from you :) I’ve got all sorts of funny stories associated with mine. After a couple of bad project demos we started stuffing our stir bar in condoms and tying them off to avoid leaks into the prototype. I got plenty of sideways looks when I pulled out a box of Trojans and crack one open while trying to show off what the thing does to people around the hacker space XD throwing my email in my profile right after I submit this.
How about humidity sensors embedded inside buildings? Like, the builder could throw a couple of them into a wall when they build it, and trivial to scan and measure the temperature or internal humidity level inside the wall (or other equipment, maybe industrial equipment) during routine inspections.
Almost every nontrivial chip has a temperature sensor inside (used for temperature compensation of factory calibrated stuff). I expect RFID chips are no different.
Can't you just get an off the shelf NFC memory chip or something, then figure out what combination of register reads are necessary to read it's internal temperature sensor?
Rough estimate based on experience +/- 2 C at best.
I'm not a chemist or microbiologist but I imagine they'd need better than that?
Having said that, single point calibration is cheap to do (just calibrate at room temp) and pretty effective.
That level of accuracy would also be useful in candy making, a secret hobby of mine. The cheap thermometers tend to have that margin of error and are pretty terrible at showing just how uneven the heat in a pan can be but I am not sure ic that has more to do with the sensors sensitivity or the refreshing on the cheap LCD display they tend to put on them.
No, 2 degrees C is about the right accuracy you need for a "proper" cup of tea or coffee. You'll lose that much heat in the transfer from kettle to cup. Inaccuracy of 5 degrees C in brewing will be indistinguishable for most people.
Precision also has a placebo effect. Coffee or tea will taste better to you if you put a lot of work into it.
This is commonly known as the IKEA effect.
This is very true but, tangentially, this is the opposite when you make drink/food for others. I found that you get the best effect when you spend a lot of effort to cook and perfect the dish but when asked, you have to pretend you basically winged it and it wasn't a hassle
My related experience was positioning a temperature sensor above a Raspberry Pi Zero and the couple watts produced by the Pi was enough to affect the measurement.
NFC gear is low bandwidth and low power. They don’t need to monitor temperature like you would in a high performance CPU or memory chip.
For example, https://ams.com/wireless-sensor-tags-interfaces