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Comment by the__alchemist | Hacker News Reader

Actual link: https://www.anyleaf.org/stove-thermometer HN truncates my links to the top URL 30s after posting.

Just released this IR stove thermometer. Uses 2 nRF52 chips, with the ESB protocol. Programmed in Rust. Source code for the sensor module is here: https://github.com/David-OConnor/nrf-hal/tree/main/examples/...

Let me know if you have any questions on how it's done.

Of note, it seems like most people wouldn't have a use for something like this, since they care about internal food temp, or test surface temp by seeing how water or food reacts. I used a handheld thermometer, but wanted something hands-free and more accurate.

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> Actual link: https://www.anyleaf.org/stove-thermometer HN truncates my links to the top URL 30s after posting.

This is probably because you have the following in your HTML:

  <link rel="canonical" href="https://www.anyleaf.org">

This is used to tell search engines and other sites that the page in question contains the same content as the page in the "canonical" link; so they should prefer to show the canonical version over the other one. I'm guessing HN also uses this for a single reason.

You shouldn't have canonical link relations to pages which are meaningfully different.

Edit: ah, I see that someone else pointed this out and you've fixed it already.

It's rewriting the URL because you have a `<link rel="canonical" href="https://www.anyleaf.org">` on the page.

Thank you! Fixed.

Oh boy I can see these guys are on a positive trajectory. These tools are useful across a broad spectrum of applications.

One of the things I would suggest is build APIs for them and people on HN will eat them up!

That's a great idea. Might be a way for tech-savvy people to custom-tune the behavior.

I have a non-food related use for this, namely:

"Is my LED cooking already?"

I've found that most lamps and light fixtures are still designed with incandescent bulbs in mind, so there's often not a lot of space left inside, and thus too powerful of a LED is going to cook itself eventually.

Maybe an edge case, but ever since I've had people forgetting to turn off my stove, I've wished there was something like this that could trigger an alarm on either temperature or timer (say, heat detected on stove for over 2 hours). A peizo beeper could make a great addition!

You should consider getting this product https://www.amazon.com/gp/product/B0863BFNWB/ref=pe_386300_4...

The canisters magnetically attach to your range hood, if there's a fire they pop open and spray a fire suppressing powder all over your stove. Very low tech, they only need to be replaced every 6 years.

I wonder what that powder is. My fire extinguisher uses a corrosive powder that is damaging to electronics especially. I think CO2 would be ideal from this point of view, but perhaps not efficient enough.

I wonder if I could make a poor man's version by filling a very thin plastic container like the kind used for bottle water and fill it with baking soda and attach it up there. If the heat melts the plastic, the powder will be dispersed and any flames will cause it to decompose, releasing CO2, hopefully snuffing them out.

This sounds outstanding, and probably quick to design / cheap to add to BOM. Will try to get it in an upcoming revision. A simple solution may be to trigger it if the temperature gets very hot - ie the sort of temp above what you'd use for normal cooking, but could happen if the skillet is left unattended. Might be able to come up with something more sophisticated too. Eg above a certain temp for an extended time.

Just install a 2-hour wall timer between the mains and the stove. Trigger the timer before cooking, it will cut the power to the stove after 2 hours (whether it is on or not). These timers are quite common in communal kitchens, e.g. in hostels. There are plug-in versions for devices like water boilers or clothes irons. No high-tech needed, always works. If you're broiling a mega-turkey you might want to restart the timer before it runs out, otherwise you won't notice it is there.

Won't work with gas burners, of course

It's not a million miles away from it though.

Typically gas stoves have a failsafe safety system that uses a thermocouple to keep the gas on only when there's enough heat.

If you used a timer to break that safety circuit (relay?), the solenoid will revert to it's safe state, and turn off the gas.

Doing that safely may be difficult. And doing anything with a gas installation may be illegal, depending on where you live.

In Australia this has only been legally required since 2017. My 2014 new house stove doesn't have it. Likely country dependent (I think more commonly it restarts the igniters instead of cutting the gas)

Sorry for the offtopicness but could you please email hn@ycombinator.com? I want to send you a repost invite.

A normally-closed gas solenoid valve is a readily available item for about $200.

https://www.mcmaster.com/gas-solenoid-valves/solenoid-on-off...

Combine with a countdown timer:

https://www.intermatic.com/Catalog/us/Products/In-Wall-Contr...

At ~$1200 DIY is a add-on fire suppression system for the range that would include a similar gas valve or contactor to shut down the range if fire suppression activated plus fire alarm klaxon and alarm system tie in possibilities.

https://guardianssi.com/

You can get those solenoid valves for around $20 online (e.g. [1]), that one is scandalously overpriced - a replacement coil costs $160...

[1] https://www.amazon.com/Beduan-Electric-Solenoid-Normally-Col...

McMaster tends to be that way, but it's got such a great catalog, that's why I end up there. I appreciate you forwarding the link for a more reasonable priced option.

At our company we have built a device which monitors your stove with an IR sensor and has an alarm for dangerous situations [0]. It does some processing on the sensor data - if it detects a dangerous situation it beeps loudly and sends you a text/call in case you are out. It can also guide you through recipes, currently there's only a small handful though [2].

We aren't entirely sure how to market it successfully though (there's an alternative landing page [1]), and the chip shortage is also affecting our ability to manufacture.

[0] https://mypippa.me/

[1] https://mypippa.me/pippa-saves/

[2] https://recipes.mypippa.me/

Nice idea for a product… one small piece of feedback from is is that whenever I see Kickstarter it is a big off switch for me.

I see it as a red flag for a product that may never actually launch.

Show me the product and let me order

Thanks for that feedback - the product is basically ready to go, the reason for Kickstarter was to get pre-orders to get enough capital to pay for a larger manufacturing run. Of course, it's quite possible to take pre-orders without using Kickstarter, so that may be a better route.

I wonder why stoves / ovens even have a “stay on forever” mode, let alone have it as the only mode. The microwave model of “be on this power for this duration and then beep and turn off” seems much nicer...

Neat. I've been thinking that such a product should exist.

Are you sampling just a single point for temperature or do you get the maximum value of a bunch of IR-pixels?

Also, with your first dollars earned, I would hire a photographer for better product pictures :)

Single point. The sensor averages the temperature of everything in a 10° FOV, which should be suitable to get an average pan temperature.

I think you could do something more clever with an IR camera like you suggest, by identifying the edge the pan, and giving more info like the temp gradient, perhaps displayed as 2 temps. Ie, "edge temp", and "center temp".

So weird I just had this idea after leaving the house with a burner on. Instead of (or in addition to) cooking accuracy I'd love a big warning light to know something in my kitchen is hot.

Why your own HAL crate? What’s different between yours and the original nRF HAL?

The `nrf-rs` HAL is quite good, but there are a few differences in my fork:

  - Replaced GPIO module with one with a cleaner API. Adjusted other modules to reflect this.
  - Replaced timer module; original was a thin wrap of the PAC
  - Tweaks to the RTC API to make it easier to set the timeout.
  - Overall, brought the API to parity with the STM32 HAL I wrote. This makes code more portable between projects for me.
  - Support for nRF-53

There were enough opinionated API changes that it would never get merged upstream in a PR.

That’s awesome! Your embedded rust is very good, that’s probably some of the cleanest embedded code I’ve ever seen. Awesome that you had time to tweak the HAL and ship your product. Makes me want to update a few embedded interfaces with better APIs.

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