Wireless Web-Serving Temperature Probe

Some of you might recall last year about this time I was talking about making a wireless probe for my smoker. Well, I finally did it. The temp probe I've used for a long time to monitor the meats finally died. No choice.

I wanted something to make my life easier. I'm usually fairly busy. And, admittedly, I'm a serious geek (proud of it, too). So, had to involve computers.

I bought an Arduino microcontroller, a type K thermocouple food-grade temperature probe with stainless-sheated leads, a WiFi shield for the Adruino, and a chip to let the microcontroller get info from the thermocouple in a meaningful fashion.

And, I had to write a little software for it because nothing out there existed (or at least, was available).

Cost? About $155. Microcontroller $35. Probe $50. WiFi shield $55. Interface chip $15. My soldering skills came free.

What does it do? It serves up a little web page that tells me the current probe temperature. I love it. From any computer in the house (including my cell phone's web browser), I can check the temperature.

What's next? Multiple probe support (including smoker ambient temperature). Text message (SMS) alerts when target temperature nears or ambient smoker temperature drops too low. Temperature graphs and long-term storage.

Here it is:

picture.php

If you patent that you will be rich. Not to mention if you sell the idea to an outside sourse the price will come down making it cheaper for the consumer. Try to find a good American company to take it over for you, one that won't outsourse it to China and you'll help create jobs in America.

Great work by the way.
 
Thanks!

Actually, my plan is to post what I'm doing here ... so that other Brethren can benefit from it ... and post their own improvements and changes. I don't need or want to make money from this.

Just want to have fun. Q is my hobby.
 
This is awesome, and gives me an idea.

I'm no hardware guy, but I've been doing software for 25 years, and I have done several jobs writing software that provides an interface or trending data to a hardware device. I'll volunteer any skills I can to create an interface for better front end info. I don't know what this device displays currently, but I'd probably be able to create something that polls the device every minute or two and creates a trend chart, alerts, etc. Not sure if I could do it via the http interface on the board...I might need to write client software to do it that simply connects to the http interface and grabs data.

What that could lead to is maybe some hardware that supports multiple probes. So say you have 4 briskets on the smoker, you have 4 probes and you can see them all in real time what they are doing. Plus a trend so you can see how the temp rose on the meat.

Like I said, I'll volunteer any programming skills I can to make a great community project if anyone is interested. My thinking is that the code should be open source, since the hardware design is as well.
 
Im not programmer... But in terms of building stuff like this Im a fast learner. Ill probably be following you on this and then make one when I get a big enough itch 8) nice work.
 
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James will know what I said! LOL
 
James,

Great job on sharing your What If ideas. What a great What If challenge to solve. I am a Huge believer in process measurements to reduce defects (Six Sigma Master Black Belt). This would allow an accurate means to measure tempature trends to produce the best quality BBQ. Here are a few suggestions:

1) I would suggest a dual probe approach per piece of Meat being measured. One to be inserted to center of meat for internal, and one for the chamber temp for that meat. They should be gained together physically on both the probe and lead to ensure ease of use and accuracy.

2) Produce a trending chart that also includes the Six Sigma Upper and Lower Limits, Mean and Medium Averages so we can improve our processes as needed. This will also show the meat's sweat tempatures and durations that will allow us to leverage for adding more flavor and moisture to get drawn back into the meat deepest.

3) Identify defects by automatically calculating six sigma levels by sigma (+-1 Sigma +-2 Sigma and +- Sigma 3) and be saved for each smoker probes to benchmark each smoker's process tolerences to improve or duplicate.

4) Add a optical sensor to measure the chambers smoke desity as a trending factor (WOW).

5) Add a relative Humidity sensor to measure the chambers Humidity Trend (WOW, WOW)

6) Add a high tempature tempature sensor to measure the heat sources trending (Holy Shiet)

I am a firm believer that constant temp and humidity does not produce the best BBQ, but rather apply the correct level of both at the correct time (Internal Temp by Meat Size & Type) is the Formula to perfection. Now only to have a device I can measure the key indicators (Internal Temp, Chamber Temp, Chamber Humidity and Heat Source Temp) in a time intraval trend would allow me to reproduce the best product. It would also allow a nice tool to benchmark these characteristics across all the smokers to compare apples to apples the key indicators used to obtain this best product.

Thanks again James for your kindness in sharing your insight.
 
Man...you guys are talking Greek to me! :lol::lol::lol: Pretty cool stuff James...:cool:
 
I can't program but I am handy with a soldering iron. I have a suggestion. What about a a group buy for the materials to put together this probe. When you buy in bulk you usually get better prices.

Stan
 
Kuyas,

That's a cool project, but for others out there who can't build one themselves, Omega sells a complete wireless kit with software that can be accesses via the web, and can also do strip charts.
 
And, sadly, people around here don't like to talk about Q. Just eat it. So, I'm alone while cooking. Around here "BBQ" is "grilling meat in a hibachi while fanning the coals to make it really hot".

I come here to this great site to talk about Q. Without you guys, I'd be lost.



I feel ya bro'....
Keep doing what you doing.
Nice device!
 
I wanted to be able to make this do exactly what I wanted. So, that meant I had to make it myself.

I don't think you HAD to. I think that with a little bit of time waiting, the Stoker really does what you want: It supports mulitple meat probes on a single serial bus and a built in web server and ethernet port allowing you to monitor food or pit temp over the network. It does not come with wifi, but an inexpensive game adapter like what I have, and it works fine with computer or phone. About the only thing you can't do is customize the HTML.

The Stoker also has some "extras" too like the abillity to control a draft fan, the OneWire bus for multiple probes, and audible alarms for doneness or out fires. You can get a Stoker with a single probe and a wifi bridge for about $250, and with a little configuration, everything will work out of the box. Extra probes are $35, or if you wanna solder, you can do your own with Grainger (who sells Omega) and the OneWire address chips.

Your kit is cool, and I'm not trying to take anything away from it, but I'm wondering why people are so interested in it, as it's not new functionality in the BBQ world. Does the $100 price difference really make it that much better? Do people hate The Stoker that much? By the time you add in functionality for multiple probes and the time/labour of putting it all together, I question what the price difference really is.

Years ago I went through something similar when I was heavy into TiVo hacking and Tridge invented a PCI adapter board that we could connect to the debug PCB to connect to it over ethernet, dubbed TiVoNet. I bought the kit, soldered it all together, did what I wanted, and thought it was great. A few years later I needed a different kit for a different form factor, and that time I had the option to get a "TurboNet" board: The ethernet was built in and it came all soldered. It was a few extra dollars, but for my time and money, it was just easy to have it work out of the box, hacker or not.

dmp
 
Your kit is cool, and I'm not trying to take anything away from it, but I'm wondering why people are so interested in it, as it's not new functionality in the BBQ world. Does the $100 price difference really make it that much better? Do people hate The Stoker that much? By the time you add in functionality for multiple probes and the time/labour of putting it all together, I question what the price difference really is.


I think for me, part of it is the "tinkering" factor. It's the same reason we have people who build a UDS themselves when they could just buy a Stumps or a Traeger or whatever.

It's not necessarily about the money. It's pride not only of ownership, but of "doing it yourself" and learning something along the way and having fun in the process. And don't forget the idea that if you did it yourself, then maybe if you have a better idea for it later, you can just go ahead and do that too.
 
I can't program but I am handy with a soldering iron. I have a suggestion. What about a a group buy for the materials to put together this probe. When you buy in bulk you usually get better prices.

Stan

I like this idea, but we might also want to review the materials list. I'm wondering if there's a way we could do it using standard off the shelf one-wire probes that you can get at a local hardware store instead of the more expensive probe bought online?

Maybe a way to interface the Arduino to a headphone jack that a cheap one-wire probe could plug into? Maybe a cheap thermistor like a DS18B20? I'm not a hardware guy so I have no clue what I'm talking about here, but just throwing out ideas off the top of my head.
 
I think for me, part of it is the "tinkering" factor. It's the same reason we have people who build a UDS themselves when they could just buy a Stumps or a Traeger or whatever.

I understand this aspect, and I know there is a lot of "I built it myself," but I've always felt the big reason to build a UDS in stead of buying a WSM was the $200-$300 price difference. If the cost, parts included was the exact same between a UDS and a WSM, but the UDS required labor on top of it, would more ppl get the UDS or the WSM? I'm just sayin....

I'm wondering if there's a way we could do it using standard off the shelf one-wire probes that you can get at a local hardware store instead of the more expensive probe bought online?

headphone jack that a cheap one-wire probe could plug into?

Threw me for a loop, had me thinking to meant Ace hardware. As far as I remember, the 1W temperature probes that come from Dallas are all designed for ambient temperature. I looked for a while trying to find native 1W devices that would go to the BBQ range, and couldn't, which is when I figured out that some manufacturors buy thermistors or thermocouples and a special general purpose 1W chip and solder away. One lead from the chip goes to the phono jack, and it's a kit, but it's surface mount soldering, not something I would ever pretend to be able to do by hand! I contacted a local component shop to see about getting the DS chips required for 1W, and they said they didn't carry them. There's also I2C which might be a bit more affordable if you'd wanna try it. You can buy the probes at a grainger if they have it in stock, and DigiKey sells 1-Wire chips.

dmp
 
Costs are definitley not even close to being the same. For a dual probe system, I'm looking at about $215. For a dual probe Stoker (with WiFi), I'm looking at $400+. WiFi is a requirement.

As it stands now, using the Arduino Duimilanove, I can support 6 probes. Each box is about $85. Each probe $65 (including the interface chip and board). I like that the probes I'm using are high-quality. The goal is to get the best value that I can. Not the cheapest.

If I want to support up to 14 probes, I can move to an Arduino Mega (about $65, fully assembled). This makes my basic box $120. Each probe about $65.

Another requirement I have is maintainability. I live in the rural Philippines. I can't just call Rock and have something shipped out to get here tomorrow without suffering great pain to my bank account. What I've built I can fix or at least afford to have spare parts lying about.

All that said, it's really not about the money. It's about tinkering and building it myself. It's about making it do exactly what I want. It's about having the system entirely open to me and allowing me to adjust it to fit my needs as they arise.

Why is there interest here? Because people like to tinker and fiddle. Because sometimes just being handed a black box just takes the fun out of it.

Honestly, I spent 5 minutes soldering what needed to be done on this kit. The rest comes assembled. I spent a few hours playing with software. But, that's 'cause I'm a software guy and enjoy it.

The software contains a complete table (0 to 200 degress Celcius, in 1 degree increments) for translating K-type thermocouple voltages to something meaningful to us. And, it takes multiple samples per second, averages those, and interpolates between the voltages to give fractional degrees. Why? Because it was fun (and relatively easy, too).

I derive a great deal of pride in looking at something and thinking "I made that". It's what drove me to write software, it's what drives me to cook/BBQ.
 
This is awesome, and gives me an idea.

Cool :)

I'm like you. Software guy. Started writing code in 1972.

I'm intentionally keeping the web interface to the board simple. I don't want to have to write a lot of software for the Arduino. It's very, very weak compared to what I'm used to.

So, I'm thinking this will be what the box serves up as its web page (0.0 meaning the probe may not be attached):

Code:
Probe 0: 60.5C
Probe 1: 102.3C
Probe 2: 0.0C
Probe 3: 0.0C
Probe 4: 0.0C
Probe 5: 0.0C

Of course, the client software should be smart and be able to take an arbitrary list of probes. Missing numbers, more numbers, etc. So, if someone were to use an Arduino Mega, there would be 14 probes listed.

My thinking is that the code should be open source, since the hardware design is as well.

I agree. My intent is to share this here with the Brethren. If others like it, build it, and use it, cool. If not, I have what I need, at least.
 
1) I would suggest a dual probe approach per piece of Meat being measured. One to be inserted to center of meat for internal, and one for the chamber temp for that meat. They should be gained together physically on both the probe and lead to ensure ease of use and accuracy.

Agreed. One might consider multiple chamber probes, too.

2) Produce a trending chart that also includes the Six Sigma Upper and Lower Limits, Mean and Medium Averages so we can improve our processes as needed. This will also show the meat's sweat tempatures and durations that will allow us to leverage for adding more flavor and moisture to get drawn back into the meat deepest.

Greek to me ... but, I'll take you at your word.

3) Identify defects by automatically calculating six sigma levels by sigma (+-1 Sigma +-2 Sigma and +- Sigma 3) and be saved for each smoker probes to benchmark each smoker's process tolerences to improve or duplicate.

4) Add a optical sensor to measure the chambers smoke desity as a trending factor (WOW).

5) Add a relative Humidity sensor to measure the chambers Humidity Trend (WOW, WOW)

6) Add a high tempature tempature sensor to measure the heat sources trending (Holy Shiet)

Not asking for much, are you? :p

I tend to agree with you. There's art to BBQ, but there's also science. I want to get the science down as much as possible so that I can focus on the art.

Thanks again James for your kindness in sharing your insight.

I'm only returning the favor already done by so many people here.
 
Costs are definitley not even close to being the same. For a dual probe system, I'm looking at about $215. For a dual probe Stoker (with WiFi), I'm looking at $400+. WiFi is a requirement

That's fine on your requirements, and I won't fault what you've done. I'm a software guy too. I had planned on buying an embedded controller and an Omega thermocouple and had already written the software to go on the controller, until I found that Omega already had a prewritten controller to do what I wanted, professionally written and auto-tuned, and if I wanted to pay a little more, it even had a built in http server. I decided for me, it was better to buy than build, but of course I'm talking about a controller rather than a reader. For all those who find this interesting, go for it. I'd be glad to help out if any one wants it, and I certainly won't call ppl fools for wanting to do their own thing. I think an "open source" version of the Stoker would be pretty kick ass, and I totally understand your reason about being so far from the mainland.

One thing to say though, I'm not sure where you are getting your numbers. A two probe Stoker shouldn't cost any where near $400! The Stoker itself is $175. Each probe is $35. You may even be able to get a progressive $5 discount if you buy a few at a time. A wifi bridge is about $40. That's about $285 without any discounts. Still more than what you'll have spent, but by my math, the break even point is at about 4 probes, and that's fine if the average person only wants 2-3. Take into account what else is there, and it's a harder decision to me. Again, I'm not saying anything bad about what you've done, and I totally get it. I'm sorry if I came across that way, but so many of the things people are asking you to add already exist. I'd be saying the same thing if some one said he found a way to build a device to pick dirt up off the carpet that only cost him $20, but took half a day to put together. And for the record, I built my own pellet pooper in stead of buying one because I wanted to do it myself, but it was also cheaper!

One last thing, and then I hope to bow out unless I can help: Some one asked for trending software I think. There is a free piece of software out there called StokerLog which does just that, monitoring your various probes and such. It keeps a log on disk, and maps the results in a nifty graph, which you are able to save. There's also a port based protocol where you can query and set just about everything about the Stoker, and I've written some of a C# library to access it.

Cool work.

dmp
 
I was thinking that one would use an WiFi access point (about $150). Not a bridge. So, yeah, your numbers are a lot closer.

Graphing and trending software is fairly trivial given modern tools (C# comes to mind immediately). As is data storage.

I understand your points about using equipment that's already built and debugged. But, I have the free time to spend on this. And, I enjoy it.

Another thing to remember: there isn't a whole lot to do here in terms of entertainment. Hobbies are all one really has. :)
 
So, I'm thinking this will be what the box serves up as its web page (0.0 meaning the probe may not be attached):

Code:
Probe 0: 60.5C
Probe 1: 102.3C
Probe 2: 0.0C
Probe 3: 0.0C
Probe 4: 0.0C
Probe 5: 0.0C
Of course, the client software should be smart and be able to take an arbitrary list of probes. Missing numbers, more numbers, etc. So, if someone were to use an Arduino Mega, there would be 14 probes listed.

What about having it spit back XML? It's a little more wordy, but also more flexible if necessary:

Code:
<tempsensor>
  <sensor type="probe" id="1">
    <value type="temp" unit="C">102.3</value>
  </sensor>
  <sensor type="probe" id="2">
    <value type="temp" unit="C">0.0</value>
  </sensor>
  <sensor type="probe" id="3">
    <value type="temp" unit="C">0.0</value>
  </sensor>
  <sensor type="probe" id="4">
    <value type="temp" unit="C">0.0</value>
  </sensor>
  <sensor type="probe" id="5">
    <value type="temp" unit="C">0.0</value>
  </sensor>
</tempsensor>
This is just a sample suggestion. Not sure how you'd want to structure it for sure. We might be starting to step outside the bounds of "on-topic" for this forum, I suppose.
 
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