6 ms·
Temperature-sensing stirbar with RFID
- cl3misch 3y agoSee also the more detailed Youtube video "Temperature-sensing RFID tag in magnetic stir bar" https://www.youtube.com/watch?v=nh1SIfipQs4 https://www.youtube.com/watch?v=nh1SIfipQs4
- londons_explore 3y agoI'm surprised there isn't a single-chip solution to this... 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?
- bboygravity 3y agoEver looked up the accuracy of those built-in sensors? 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?
- londons_explore 3y agoWhen calibrated they're usually far better than that. Just they normally aren't factory calibrated because temperature sensing isn't the primary purpose of the chip and calibrating temperature sensors is very expensive at scale (have fun heating up every wafer to a very precise 100C and cooling it down to -40C just to record temperature sensor output). Having said that, single point calibration is cheap to do (just calibrate at room temp) and pretty effective.
- m463 3y agowouldn't it be easy at scale if you have RFID?
- 0xEF 3y agoHeck, you need more accuracy than that for a proper cup of tea or coffee. 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.
- Cheer2171 3y ago> Heck, you need more accuracy than that for a proper cup of tea or coffee. 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.
- regularfry 3y ago> 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.
- ithinkso 3y ago> Coffee or tea will taste better to you if you put a lot of work into it. 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
- ta988 3y agoIn chemistry it is usually fine, in microbiology it can have a serious impact on yoeld. But those sensors can often be calibrated just with a simple coefficient.
- HankB99 3y agoI wonder if the internal heating of the chip would affect the reading. 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.
- Aurornis 3y agoNFC chips don’t have any need for temperature data, so a temperature sensor and the necessary blocks to convert it to digital wouldn’t be a priority for a cost reduced NFC design. 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.
- azubinski 3y agoThere are single chip NFC interfaced temperature meters of course. For example, https://ams.com/wireless-sensor-tags-interfaces https://ams.com/wireless-sensor-tags-interfaces
- endiangroup 3y agoAD: Yes, what a wonderful application of tech. I very much enjoy seeing these hardware <> software open source projects. Congratulations on developing a finished project.
- HPsquared 3y agoSuch an elegant solution. This method could also be used to embed similar things. 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.
- waldothedog 3y agoThis is being done in the “high performance” home building space. I don’t think it’s standard practice, but it gets talked about on the Fine Home Building podcast a decent amount
- stavros 3y agoThis seems like a great solution, I wonder why they didn't move on to selling this. Maybe because that's not as much fun as making it.
- themoonisachees 3y agoBecause the people using the old solution aren't the ones buying it. A chem lab is going to be stocked with the equipment everyone used in chem school, and the people who went to chem school are going to require that equipment. Yes, it'd trivial to change processes to use this new solution, but every chem lab in existence already has a thermometer and a hot plate with stirring, so the expense makes very little sens on its own.
- apprenticemason 3y agoI created a similar product almost 10 years ago, I had a provisional patent filed and showed it off to some very nice and smart people at Thermo Fisher. I wanted to license the patent to people that actually know how to build laboratory equipment (I don’t hold a higher degree in anything). I should’ve continued trying to license but they convinced me that was the wrong move. 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=ygUbUGhpbmRpbmcgc29sdXRpb25zIHN0aXIgYmFy https://m.youtube.com/watch?v=RrBhliK1ryY&pp=ygUbUGhpbmRpbmc...
- kohbo 3y agoThat's rough. Thanks for sharing your experience. On the other side, I hope your life came together in other ways.
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- zafka 3y agoHi, my email is in my profile if you care to connect. I started an apprenticeship as an electrician at the age of 27. I received my Journeyman's card at 31 - Funny thing is that here in FL, there is next to no benefit in having a journeyman card unless you are using it as a stepping stone to a Master's license. There was a severe building slump when I got my card, so i figured it was a good time to go back to school full time. ( I had been going part time while working as an electrician.) Now quite a few years later .... Hell, not gonna bore everyone. Anyhow, give me a yell if you feel like it.
- bkraz 3y agoI'm always happy to see one of my own projects on Hacker News. Let me know if you have any questions.
- natebleker 3y agoWatching you work through projects has brought me so much joy over the years. Thanks for putting stuff like this out there for the world!