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Obsessed over the amount of warmth in the white. Not pictured: "Eggshell". Like musical notes, colors only come alive in the context of other colors.

But out of our hands—it's being manufactured now. Still time to get the preorder price and ship next month: http://store.supermechanical.com/collections/range-dial

[supermechanical]

The post-ownership society

The smart home market is experiencing growing pains. There’s a disconnect between Silicon Valley — where everything from living quarters to companies are fleeting and cash-burning — and the average homeowner, who cannot afford to fail fast because the only money we were given was a 30-year mortgage with our home as collateral.

The software-is-eating-the-world mentality is now being applied to hardware in the worst ways. Products suck away data to their brains in The Cloud and then shut themselves down. Perhaps tech companies have fooled themselves into thinking that this was okay because we’ll pay $800 for a new smartphone every two years.

But these innovators are altering our relationship with home objects that we normally rarely think about. Previously unheralded yet critical functions of our homes are being turned into gadgets. Modern gadgets challenge traditional notions of ownership, and that creates some issues.

Reliability

Reality: you may have to agree to new licensing terms to continue using your object (see: Nest), or code critical to the function of your object can disappear at any time (see: every smart product ever). Did you buy the product, or just an empty physical vessel that is given life by the grace and financial stability of its manufacturer?

It’s accepted that software has a shorter service life than most products, but if we’re going to see technology integrate into our homes in a meaningful way, contingencies are necessary. A company should be prepared to remove dependencies for the customer — whether that means open sourcing the server code or using an escrow account to ensure there will be money to keep the servers on.

Even though we no longer sell Twine, the servers it relies on are still running five years later. We do this because 1) revenue from a paid account level covers the expenses, 2) most of the customers now using Twine rely on it to alert them of home disasters, and 3) we want to customers to come back when we make future Twine-like objects. But you shouldn’t trust companies to do the right thing.

Generational products

Nest shut down Revolv not because it couldn’t afford it, but because of a philosophical stance. When Steve Jobs observed that death “clears out the old to make way for the new”, some people chose to apply that more rigorously to their product line.

Given that hardware startups are expected to burn cash to quickly reach an exit for their investors, it’s no wonder they burn their customers as well. Few businesses are thinking about what’s best for anyone 25 years out when they're trying to lock us into the Internet of Keurigs.

But a long view is just what’s needed. It’s already hard enough to find smart home products that are truly valuable. When they do exist, how can manufacturers build consumer electronics to age gracefully?

I don’t know yet. Support periods could be legislated, or we can let but I want to see companies design ownership into products first. Perhaps old-school manufacturers can take their product categories back with thoughtful modernization that’s rooted in a viable business model. Maybe we take the complexity out and consumers happily buy inexpensive single-minded objects like the Clapper. Maybe we pick up lessons from longer-lived products like furniture, to build heirloom electronics that appeal to heart and head. Manufacturers and entrepreneurs, the market is paying attention — let’s set an example and design next-generation home technology to actually last through the next generation.

Borrowing the “ownership society” phrase from @mainsequence, who borrowed it from Ronald Reagan.

[supermechanical]

The Arduino-compatible kitchen

Our new Bluetooth cooking thermometer, Range Dial, has met its goal on Kickstarter, and we’re manufacturing it. But we haven’t mentioned one feature: it’s user-hackable.

We love making tools to help others make their own tools, a trait picked up at the MIT Media Lab. Every product we’ve made has been moddable to some degree, and you’ve used this to solve problems we never knew existed. That’s awesome, and with Range Dial, we’re going further.

The first Arduino-compatible consumer device

Out of the box, Range Dial is a precision Bluetooth cooking thermometer with two temperature probes and a dial to choose preset temperature alerts—painless to use with or without an app. Like our previous thermometers, most professional and enthusiast cooks will love it as is. 

But you can replace its firmware with an Arduino-based one that unlocks the hardware. The probe ports are full I/O—use them for your own sensors or actuators. Assign new meaning to the dial positions. Or build with the iOS SDK if you just want to make a mobile app that interacts with the hardware.

What you can do with a moddable Range Dial

All this is a first for a consumer appliance. We think it’s possible to have both a polished experience, and access under the hood for power users. Range Dial can be an all-purpose kitchen sensor and controller—a KitchenAid for data. Some examples of what you could do:

Add fan control to a smoker

Maintain the temperature of a kettle or lagering fridge

Monitor and control an aquarium’s temperature or pH

And ideas that we haven’t thought of; that’s the point. You’re the expert at what you do. Make Range Dial into your own tool.

The Kickstarter ends Thursday—get a discount and early shipping when you preorder Range Dial now. We'd appreciate your support.

[supermechanical]

Update 2: Goal achieved. Let's keep going! (And, details.) · Range Dial. Better looking, smarter cooking thermometer.

We did it—thanks to our backers for funding Range Dial. The campaign is only half over, so please tell your friends, family or favorite food website about us tonight—Kickstarter works best when backers get involved and share a project with others. http://kck.st/1GbK1Ho

https://www.kickstarter.com/projects/supermechanical/range-dial-connected-food-thermometer-that-lets-yo/posts/1397150

[supermechanical]

What A Kickstarter All-Star Learned From Sudden Failure

The company behind Twine had its last product flop on Kickstarter. Having licked its wounds, it's ready to go again.

FastCoDesign talks to John about what went wrong, and what we learned in order to come back with Range Dial.

[supermechanical]

Range Dial. Better looking, smarter cooking thermometer

Range Dial is the handsome, steel-capped evolution of our first smart thermometer, Range. We've learned a lot from how our customers use Range, and added the top requests: Bluetooth for wireless monitoring, and a second probe for ambient temperature. But we also thought carefully about how to make it work with as little fussing as possible.

Range Dial works with or without a smartphone. Having a connected device shouldn't mean you have to mess with an app for the most basic functions. Just plug in the probe and turn the dial to a preset—Range Dial will beep at you, and you'll also get a push notification on your phone when your food is done. Or open the app to have full control. It's the best of both worlds.

Learn more on Kickstarter.

[supermechanical]

Why is Range good for homebrewing?

A while ago, John got the chance to hang out with Jay from Austin Homebrew Supply and his friends who were brewing on a beautiful Austin Sunday. Trevor was hosting in his garage, with a custom-made double-burner rig, and previous successes on tap. Jay got to try out his new Kickstarter reward, an Aqua Range, with his iPad, and it came in handy with two batches in different stages going at the same time.

Whenever it came time to clean (frequently), the business end of Range got dropped in the tray filled with sanitation solution along with the rest of the equipment (the silicone and stainless assembly is easy to clean), and then it was back to work. In testing next to Trevor’s existing ‘dumb’ thermometer, Range won the brewmasters’ trust by matching it degree for degree. We put a lot of effort into making Range accurate, but that’s not the only reason it's good for homebrewing.

With remote alerts for time and temperature, you know won’t miss anything while you’re taking care of other tasks. Perhaps best of all, Range also allows you to see a graph of the temperature over time — and export that data to pore over later so you can see exactly what happened with each batch as you perfect your process.

The next update of the free Range app will give you even more awareness of what's happening. We’ve developed Rangefinders to visually show the temperature bands that brewers (and candy makers, and grillers) care about, and give you a little notice when your mash has entered or exited a band. Further, since brewers constantly tweak variables like temperature on their recipes, you'll be able to make your own Rangefinders as well. 

Back when we brewed our first batch of SupermechanicALE solo with a recipe from Austin Homebrew Supply, we were worried about the results, but it turned out decidedly beer-like. If you're like us and trying new things to become a better brewer, tools like Range give you information you can use to learn and mark your progress. Happy brewing! Have a beer.

[supermechanical]

Why Bluetooth can suck (but doesn't have to)

Two decades ago, Bluetooth 1.0 was invented. The point was to replace simple data cables with short-range radios. Sounds like a swell idea, but it was bad. The 1.0 standard was lacking, adoption was slow, devices often didn’t work together at all, and even “good” connections were sluggish, unreliable, and ate through batteries. But twenty years is a long time, and with version 4.2 of the Bluetooth standard just around the corner, the potential in these devices has never been greater. They can be amazing, but that doesn’t mean it’s easy or cheap to make them so. Some companies still skimp, but that’s not our style.

If you have a Bluetooth device that doesn’t work well, it could be a lot of things. Maybe they picked a cheap chip antenna or designed their custom etch antenna poorly. Maybe they forgot to check their antenna’s directional radiation patterns, or didn’t bother to do in-system tuning of the reactive matching network. Maybe to get the battery life they promised you, they had to unconditionally knock 10dBm off the radio transmit power and abandon their fade margin. Or maybe the engineers did everything exactly right, but then their managers had the electronics made offshore where dielectric requirements often go out the window, and it’s common for inferior components to be secretly swapped into the build to cut costs.

You don’t really need to understand or worry about those things; we’ll do that for you. And when we’re done with that, we’ll have Range Oven Intelligence tested and certified by the Bluetooth Special Interest Group, just so you’ll be sure. That’s the only way you’re allowed to put that cool, pointy little Bluetooth logo on your product, and only products bearing that logo are guaranteed to work together. Supermechanical’s attention to detail is our most plentiful resource, and that’s all you need to get Bluetooth just right.

[supermechanical]

Engineering accuracy: thermistor vs thermocouple

We get a lot of questions that sound like this:  “How can you say thermocouples are less accurate than thermistors? I have a Thermapen and it is very accurate! You [turkey/rascal/hooligan].*”

First let me say that Thermapen is a perfectly good product and Thermoworks, the company who makes it, seems to be exclusively employ very nice people. They make a wide variety of industrial and scientific thermometry tools, and have the skills to do a good job. But Thermapen was designed to be fast above all else; its accuracy is in spite of its thermocouple, not because of it. There are a few reasons for this to be true, but the biggest and easiest to understand has to do with a technique known as “cold junction compensation”, or CJC.

I mentioned in Part 1 of this series that thermocouples are differential temperature sensors, and by that I mean that they can only be used to measure the difference between two temperatures. For a thermocouple, those two temperatures are at the “hot” end and the “cold” end of the wires. A thermocouple by itself can tell you that the hot end is 90℉ hotter than the cold end but it can’t tell you that the hot end is 165℉. That’s just how they work. To take an absolute temperature measurement with a thermocouple, you have to know the absolute temperature of the “cold” end ahead of time. Measuring the absolute temperature at the cold end (75℉) and then adding that to the thermocouple’s differential measurement (90℉) to get the absolute temperature at the hot end (165℉) is called “cold junction compensation.”

Any type of absolute temperature sensor can be used for CJC, but all the error in CJC adds directly to total error, so doing a good job of CJC is important. If you’re willing to void your Thermapen warranty, you’ll find a thermistor on its circuit board, right between where the two thermocouple leads are attached. Nearby you’ll see the letters “CJC,” silkscreened crisply in white ink.

The accuracy of their thermocouple measurement depends on the accuracy of a thermistor measurement. All things being equal, how could a thermocouple/thermistor solution be more accurate than a thermistor-only solution? Is thermocouple error zero? Is it less than zero? No, of course not. The Thermapen design achieves good accuracy by calibrating every unit individually after they’re built, which allows system errors (from the thermocouple, CJC, amplifiers, etc) to be quantified and subtracted away. The Range and RangeOI design achieves good accuracy by avoiding all that error in the first place. It does not require calibration to be accurate. We just build them that way.

*No one has actually called us a turkey, rascal, or hooligan. 

[supermechanical]

Engineering accuracy: designing ohmmeter electronics

Even an expertly engineered thermistor probe is useless without an accurate method of measuring its electrical resistance. Recall from part 1 of this series that a thermistor is nothing but a resistor whose resistance is a function of its temperature. Over its full operating range of -40℉ to 450℉, the thermistor in Range Oven Intelligence varies from about 1,000,000Ω to about 10Ω. A device which measures resistance is called an ohmmeter, and there are special challenges in designing an ohmmeter into RangeOI that can accurately measure such a broad spectrum of resistances. Ignoring those challenges would be like trying to measure your neighborhood with calipers or pulling out a measuring tape to measure grains of sand.

Designing Ohmmeter Electronics

Ohm’s Law is one of the most practical laws of electronics design. It says (among other things) that the voltage across a resistor is exactly equal to the product of its resistance and the current flowing through it. Symbolically, V = I x R. That law supplies the fundamental principle of Range OI’s measurement technique. To take a measurement, the Range OI electronics pump a variety of small bias currents through the thermistor, measure the thermistor’s voltage at each one, and use all that data to deduce the thermistor’s resistance from Ohm’s Law. Once the resistance is known, so is the temperature.

Identifying and minimizing the myriad sources of ohmmeter error is important for overall accuracy. Here’s a brief rundown of some of the types of error and how we get rid of them:

Bias current error - From Ohm’s Law we can see that carefully controlling the thermistor bias currents is the first step in taking an accurate reading. We use ultra-high-precision bias resistors and carefully-selected transistors to set all the bias currents.

Input voltage noise - Current through the thermistor makes a voltage we measure, but that voltage is victim to all kinds of corrupting electrical noise; it can come from other parts of the design, as far away as outer space, and many places in between. Careful design, signal integrity analysis, and certain numerical techniques obliterate this source of error in Range OI.  

Reference voltage error - An analog-to-digital converter (often ADC, for short) is a device that compares an arbitrary analog input voltage to a known reference voltage and generates a digital representation of their ratio. A high-precision, low-noise reference voltage like the one in Range OI is essential for accurate ADC operation.  

Quantization Error - The act of converting a signal from analog to digital is inherently inaccurate, because the analog signal has to be rounded to the nearest available digital representation. However, this type of error diminishes quickly as the resolution of your ADC increases. Using a 12-bit ADC in Range OI, along with carefully selecting all the bias currents, takes this error off the table almost completely.

We wrote Engineering Accuracy to show what goes into making our thermometer accurate, but we put the same amount of attention and dedication into every aspect, from the app to the packaging. We’re this meticulous about everything.

[supermechanical]

Engineering accuracy: understanding material properties

Now that we've picked out the thermistor for Range Oven Intelligence, it has to be designed into a great probe to reach its full potential. The quality of the probe can be seen in the quality of the materials, and materials are understood exclusively through their properties. Every material has dozens of different properties which can be carefully studied and measured; a select few of those properties play a special role in making sure RangeOI is accurate, fast, and durable.

Understanding Material Properties

Thermal conductivity is a measure of how quickly energy flows through a sample of material when a temperature differential is applied. To make the thermistor in Range OI responsive, we maximize thermal conductivity between the outside of the probe and the internal sensing element through use of ceramic thermal grease. Using that grease to replace the air gaps inside the tip of the probe yields a highly conductive path all the way from the sensor, through the thermal grease, through the steel probe wall, all the way to your dinner. That thermal path is important for both response time and absolute accuracy.

Being able to leave the probe in the oven as long as you want is essential, which is why all the materials chosen for the probe design have high service temperatures. A material’s service temperature tells you how hot (or cold) something can get and still retain its other critical properties. We make our probe out of silicone rubber (service temp: 600℉+), copper and steel (both 1000℉+), a dab of thermal grease (600℉+), a thermistor (450℉), and nothing else. It isn’t a guess when we say the probe is rated to 450℉, so if you manage to melt yours, we’ll almost be impressed.

If you grab both ends of something and pull hard enough, you’ll rip it apart. Tensile strength is the property associated with how hard you’d have to pull to make a material or assembly fail, and is typically expressed as a pressure (for materials) or a force (for assemblies). We’ve engineered the probe assembly to a high tensile strength of several pounds, preventing the thermistor wiring from being pulled out of the steel tip. Making sure the thermistor stays in the tip of the probe where it belongs is important for making reliable measurements.

The probe tip is made from EN1.4301, a widely-used stainless steel alloy with many exceptional properties. Aside from high corrosion resistance, elastic moduli, and Rockwell hardness, this steel alloy is especially ductile. Ductility refers to a material’s ability to be formed by operations like stretching or drawing. This ductility allows for strong steel tubes to be manufactured with thin walls. Those thin walls minimize heat capacity, which is the measure of energy required to increase the temperature of an object. To achieve good response time and accuracy, low heat capacity is just as important as high thermal conductivity.

In part 3 of this series we’ll examine the final pieces in our accuracy puzzle: electronics design and analog-to-digital converter fundamentals.

[supermechanical]

Engineering Accuracy: Choosing the right sensor

To design an accurate digital thermometer, you have to do three things right. First, you have to decide what kind of temperature sensor is best for your users and their needs. Second, you have to design that sensor into your thermometer so that it is fast and reliable. Last, you need to understand how to digitally measure that sensor so you can give your users an accurate and useful temperature reading. Today I’d like to tell you about the first of those steps. So strap yourselves in, cause it’s time to learn a thing or two about:

Choosing the right sensor

We’ve never met, but I can guess at what you care about in a thermometer. It must be accurate and shouldn’t force you to wait too long for a good reading. It should be able to indefinitely handle the temperatures you want to measure. It should reliably do those things for the best price possible.  

The sensor question often comes down to “thermistor or thermocouple?” There are many other sensor technologies too, like metal RTDs and silicon bandgap diodes, but those are usually not ideal for digital thermometers. A thermistor is a little chip of semiconductor whose electrical resistance varies and is proportional to its absolute temperature, up to as much as 500℉. A thermocouple is a welded junction of two different metal wires which creates a small voltage proportional to a temperature differential, and works fine in excess of 1000℉.

Thermistors have more mass than thermocouples, so they take a little longer to respond to temperature changes. Thermocouples are a few pennies cheaper than thermistors too, but don’t let that fool you into thinking that using a thermocouple would make the whole thing less expensive. Compared to a thermistor, a thermocouple requires much more expensive interface hardware before it can be used properly. Aside from the cost, the addition of all that hardware means that thermocouple-based solutions typically end up being less accurate than thermistor-based alternatives. It’s just like the Telephone Game kids play; the more people who get involved, the more distorted the message becomes.

Thermocouples respond faster and work at insane temperatures. Thermistors are more accurate and much less expensive. Compare their benefits. They both have their place in the wide world of thermometry, but which is right for Range Oven Intelligence? We chose to use a thermistor. Range OI isn’t for firing pottery or laboratory chemistry. RangeOI is for smarter cooking. And in a kitchen thermometer, thermistors just make more sense.

Join us next time for part 2 of this series where we’ll talk about how to get the most out of our thermistor, including the value of a little thermal grease and our favorite properties of silicone and steel.

[supermechanical]

What is Oven Intelligence?

A year ago, the handful of individuals who make up Supermechanical set out to make a thermometer. It would be fast, accurate, and tough. It would be made of the best materials, and include a beautiful app with features you couldn’t get anywhere else. The campaign for that thermometer raised $177,000, and today we’ve shipped thousands to backers and more through our own store, Food52 Provisions, Austin Homebrew Supply and Amazon. Range is exactly what we always wanted it to be, but now making a good thermometer comes naturally. Why stop there?

Range plugs right into your iPhone or iPad, but Range Oven Intelligence connects wirelessly using the Bluetooth Low Energy standard. This also allows us to add support for Android devices, a feature which was an unfortunate impossibility in the past. We know that wireless and Android support are very important because you’ve told us so, but there’s nothing very Supermechanical about them. So we kept going, and named the results “Oven Intelligence.”

Oven Intelligence is extra electronics that no one else has, and it’s also the set of app features that put those electronics to work. Oven Intelligence is the ability to tell if you accidentally left your oven on, or if your oven is finished preheating. Oven Intelligence allows basic interactions directly with the base so you don’t have to pull out your phone when your hands are messy. Oven Intelligence doesn’t just tell you your steak is 94℉ right now; it tells you your steak will be medium-rare 3 minutes from now.

The wedge-shaped base of Range OI contains a dedicated, precision temperature sensor. It’s the same technology we use in the business end of our thermometers, but you’ll never touch it and you’ll never see it. It's built into every model of Range OI, and it's there to serve a singular purpose. With the base mounted to your oven, Range OI can always tell not just whether your oven is on or off, but also for how long, and whether it is warming up or cooling down. That little bit of information goes a long way to make sure you waste less time while cooking food accurately, and to prevent potential kitchen disasters. The majority of home fires happen in the kitchen, and the leading cause is leaving cooking appliances unattended.

If you’ve ever thought very much about your remote control, it has probably occurred to you that buttons are gross. Gross has no place in the kitchen, so Range OI has no buttons. Instead, we added an accelerometer. This allows you to tap the base to hear internal temperature and done time, clear alerts, and perform customizable functions, like setting the 5-minute timer you use for your coffee every morning, all without grimy mechanical buttons. Oh, and we added support for the Pebble smartwatch for the same reason: you don’t want to pull your phone out of your pocket all the time while cooking. Most of the interface will still be on your phone where it belongs, but Oven Intelligence puts some of it back into the real world.

You could use this as a great thermometer (which it is), but with Oven Intelligence, it is so much more than just a thermometer. It’s an upgrade for your oven. Back Range OI on Kickstarter to get one.

[supermechanical]

Introducing Range Oven Intelligence

Range Oven Intelligence is the kitchen assistant you've always wanted and the brain for your oven or grill that you didn't even know you needed.

Range makes precision cooking easy, alerts your phone or Pebble smartwatch that you left the oven on when you're leaving home, and of course, tells you the exact temperature of your food.

supermechanical.com/rangeoi

[supermechanical]

We've been working on something — and it's not a new way to store your Range. 

Stay tuned.

[supermechanical]

Range app v1.2

Version 1.2 of the Range app is now live in the app store — that means it's time to get excited about some new features.

Range should work with 3rd generation iPod touches and newer now (well, when the update is live)!

You can now find Range finder templates for candy and meat in graphing mode. When you’re making candy, you can easily see at a glance how far you are from hard crack and the perfect toffee. Time to grill steaks? Make sure your dinner turns out perfectly medium rare — and stay away from the leather zone.

The timer also got a big overhaul — now you can set a timer for more than two minutes into the future! Make a clockwise circle around the center of the screen to set a timer (or add time to a timer) and counterclockwise circle to remove timer or delete a timer.

[supermechanical]

Cook up the perfect Mother's Day with Range

Whether your mom loves to cook or you love to cook for her — Range will help cook up the perfect Mother’s day.

Start out the day with a simple breakfast in bed for Mom. Perfectly soft boiled eggs — served on homemade toast of course.

Just make sure you do all the dishes before she makes it to the kitchen.

If it's a nice day, grill some chicken for lunch — with a salad on the side. Mom wants you to eat your vegetables.

Tea time is perfect for an afternoon treat. Maybe some Cinnamon Toast Crunch toffee?

And for dinner — we all know you could make the perfect roast, but treat Mom to a night on the town. She deserves it.