Thermostat Update Version 3.2

I suppose it’s about time to let you know about the multitude of changes in my thermostat. If you’ve been following along, you might be surprised that I’ve jumped all the way from Version 2.0 to Version 3.2, but that’s just how drastic the updates have been. You can read about version 1 here, and the version 2 update here, if you want the backstory.

Is that a Photon in your pocket?

Yes (and I’m happy to see you). The Particle Photon is a programmable wifi microcontroller. The version 2 update included the Photon, but it only served as a link to the internet for basic control and minimal monitoring. The system still ran on the Arduino platform. Now, the Photon runs 100% of the system, and the Arduino has been phased out. This gives me full control, and full monitoring capabilities.

Don’t Blynk, you may miss it.

Blynk is an app that allows you to communicate with your microcontroller projects. It works with a number of popular platforms. You can read data from your hardware to keep tabs on it, or you can write data to the hardware to control it. It is very simple to set up, and has proven quite flawless. As you can see in the pic, I am monitoring temperature, humidity, and furnace runtime. This data is also being graphed. The graphed data can be output to a csv file as well.

I’m also using Thingspeak as a primary means to log data for analysis later. There is a graph at the end of this post. It it one of the live feeds from the system to Thingspeak. You can see the whole public feed here.

Alexa, I’m freezing my testicles off.

I have incorporated an Amazon Echo Dot into the equation, using the IFTTT service to link everything together. I can tell the Echo to turn the furnace on or off, and trigger it to certain temperatures. You can’t use IFFFT to send variables, so I can’t pick any random temperature, the control has to be pre-defined. I had to write a function for 65°F, and one for 70°F.

Look, Ma, no hands!

Between the Blynk app, and the Echo/IFTTT integration, the system runs without me ever actually interacting with it. I rarely ever use the buttons on the physical interface. The delay function I added in V2.0 was recently incorporated into the app. I also added indicators for the temperature setting and the standby status, which makes it more clear that the system has responded to my remote commands.

This is crazy, but here’s my number. Text me, maybe?

The IFTTT service is also set up for texting. I can text it an ON command, or a specific temperature. It will respond to confirm the action. The system will also text me if the temperature drops below 38°F, because that means that my propane tank has run empty (Yes, that has happened when I was gone overnight. Yes everything froze. Luckily, nothing was lost. My water system thawed out and worked fine). The IFTTT service limits you to 100 texts per month, so you have to be mindful of when you use that type of notification. My 38° notifications (being high priority) are quite incessant, and come in waves that will quickly trip that threshold.

A day in the life.

So here’s what a typical day might look like. Before bed, I will determine what time I plan to wake, and set my delay for one hour earlier. Then I tell the system to turn off and crawl into my sleeping bag. The temperature is allowed to drop to 40°F overnight. When I wake up, the system will have been on for an hour, and it will be close to 60°F. I tell it to turn off before iI leave for work. If I forget, the motion sensor will do it for me after an hour. Before I leave work for the day, I’ll will check in. The system will be in standby mode (40°F) since there has been no motion for over an hour. When I hit the ON button, I can clearly see the system come out of standby mode, set itself to 60°F, and turn on. I can also set a specific temperature, if required. When I get home, it’s nice and toasty. Lather, rinse, repeat.

Thanks for reading. As a parting gift, enjoy this live graph of the temperature in the camper. It updates every 2 hours.

The RoboGarden or, “Do Android Cukes Dream of Electric Salads?”

Garden Brain
This is Carver, the brain.

I’ve been so busy DOING this project that keeping updates here has eluded me. I had previously written about the Food Computer concept being deployed by the MIT Media Labs Open Agriculture Initiative. I was keeping an eye on the progress over there, intending to build one of their systems. I decided to temporarily “do my own thing” for a couple of reasons. For starters, their system is in development, and jumping in now requires a level of knowledge that escapes me. I’m just not up to speed on the level of software development required to use their approach right now. Second, I have decided that building my own setup based on a traditional hydroponic system has more value and efficiency for me at this juncture. I eventually hope to have a system that is 100% compliant with the MIT approach, so I can contribute to the data gathering, educational, and community based initiatives they are so gallantly spearheading.

So, why go your own route? 

As I mentioned, my software development abilities drift far behind my hardware abilities. I am a bit lost looking upon the sea of code that MIT has out there. I have already put a number of the pieces together in preparation, but I knew my own approach would be a less frustrating way to actually get results. Reason number two is cost. By some estimates, the food computers can quickly run between $2,000 and $3,000 (depending on who you talk to and what materials you source). I have a currently running system that has cost me $1000 to date, and is just about to produce food. A third reason is the systems footprint. My system has about 4 times the grow area of a standard food computer (in fact, my system is almost better described as a “food server” in some regards). This means I can grow an actual useable crop. The standard food computer is a great opportunity to experiment, but the actual output would be pretty low as far as trying to feed myself. And thats my fourth reason, feeding myself. I have a lofty goal that someday I will grow 100% of my own food, so this is a step toward that goal (especially in the winter). I don’t eat meat, so veggies are the only thing I need to produce. Those of you that follow this blog will say “Hey, didn’t you write about eating the squirrels that plagued your camper?“, and you’d be right! Well, that was then, this is now, get over it (smiley face). Of course, going my own way has some disadvantages.

What are these disadvantages of which you speak?

Well, many of the problems have yet to surface, I’m sure. I’m on my first crop, so I have no idea what the final results will be. Will I get fruit at all? Will it taste like cat food? Who knows. A big problem is that my system is just one large system with one climate, one light cycle, and one nutrient spread. I have to be cautious what array of seeds I plant. If they require different nutrients or lighting,  or have vastly different timing of growth stages, or different tolerances of heat, humidity and pH, it just won’t work. My idea of a constantly rotating crop (eating one crop while starting a new one) is likely to be impossible. I may have to do one crop, can/freeze/preserve it, and move to the next. Perhaps I will reserve its use to crops that cannot grow in my difficult climate, and stick to soil for others. It’s a lot of question marks that will only be answered with time and results.

The most important disadvantage is that my system limits the data and knowledge I can contribute back to the MIT project, which is open source. Wanting to support their open source initiative is my motivation to push myself to build a proper food computer ASAP.

Blynk App
Remote monitor and control courtesy of the Blynk App

Cool story, just tell us about your setup already.

So it’s built with the Particle’s Photon microcontroller. It uses a temperature/humidity sensor (an AM2315), and a simple LDR to sense light levels. There is a propane furnace keeping it warm in our sub-zero temperatures. The brain (pictured above) uses a bank of relays to control two dual gang outlet boxes. The left 4 outlets are individually switchable, while the right are switched in pairs. This controls all of the pumps and lights and fans.

My code tells everything when to turn on and off. It can be overridden and manually controlled using an app called Blynk that talks to the system remotely and also allows me to monitor from afar. It texts me when the temperature drops low, alerting me to change the propane tank. That’s all setup using IFTTT.

In terms of hydroponic style, it’s a flood and drain system. The pump runs long enough to fill my tray, which then drains back to the holding tank. This keeps the roots wet and oxygenated. The water has a nutrient solution balanced for the needs of the plants. The water is oxygenated with a pump, much like a fish tank is. The pH is controlled via application of acids/bases depending on careful readings from a meter. I’m using a Hannah 98129 Combo meter that tests pH, Conductivity (EC), and Total Dissolved Solids (TDS). My grow light is an 8 tube, 40,000 lumen, T5 fluorescent unit by Agrobrite.

Operation Transplant

I started seeds on 1/20/17. By 1/31/17, I had seedlings ready to transplant. The seeds were started in rockwool cubes. The seedlings (cube and all) were then transplanted into net pots filled with an inert clay substrate. Every hour, the tray floods and drains. The light initially stayed on for 18 hours a day. Today, that changed to 12 hours a day. This is interpreted by the plants as the days getting shorter. It’s their cue to start flowering and producing fruit.

growth progress
Salad O’clock?

When my cucumbers began to reach out vines, I set dowels out to catch them, but today I switched that to a net trellis. I also switched my nutrients to a flower/bloom friendly variety. As you can see by the picture, I have come a long way from seedlings.

As always, anyone who would like to build something like this is welcome to my code, which I will probably place on GitHub at some point. Just email me from the contact page. I’ll write more when I start seeing fruit.

Nerdfarmers unite!


Keeping Warm Part II

At the end of last winter, I wrote the first of a two part series on how I keep warm. As I enter the grips of winter once more, I thought it was time for part II. The first part was all about my thermostat.  If you’ve been following along, you know the thermostat has changed a lot since that post, and it continues to be refined. Today, I will talk about the hardware (furnace and other heaters) and “software” (clothing), and other techniques I employ.

Plastic banking installed.
The Igloo Cometh.

The first line of defense is the camper exterior. Like any home, it’s a battle to keep the cold air out and the warm air in, but to also maintain some ventilation to keep humidity at bay. For me it begins with banking the camper with plastic sheeting. This keeps wind from rushing under the floor. When the snow comes I can bank snow against the plastic. Show is a phenomenal insulator. I line all exterior compartments with standard 3.5 inch loft pink roll insulation (pics below). The camper is covered with tarps. The snow can accumulate above without directly contacting the roof. Keeping the roof dry is preferable. If the snow collected on the exposed roof, and then melted on a warm day, the resulting water will find is way into small spaces. When the cold re-freezes the water, it expands. Suddenly those small spaces become cracks and water leaks.

Reflectix used for carpet pads.

On the inside, I fill vents with pink roll insulation, and then cap that off with 1 inch blue foam board. I also covered the large rear window with blue foam, as well as the windows around the bed. They would be an enormous loss of heat, and I get plenty of light from the two remaining windows. The remaining windows get the standard shrink plastic on the interior. The larger dining area window also gets a custom exterior storm window made from plexiglass against a rubber gasket. I have runner carpets on the floor year round, but for the winter, I place Reflectix insulation under them. This is sold under a number of brand names and styles, but it is basically bubble wrap between two sheets of heat reflective mylar (think space blanket). It adds a level of protection from the cold floor. Finally, a wool blanket hangs in front of the door to help mitigate drafts.

Behind this guitar is the drivers seat.
The blue closed cell foam provides a cold barrier for my self-inflating camping pad bed.

The cab of the camper is a standard van cab. It is not really insulated at all. Rather than try to insulate around such a compound shape, I walled the whole cab off with blue foam board. I do lose that space for interior storage, but I can still access it from outside. The wall does make the space a bit cozier. There’s something about having a steering wheel in your living quarters that doesn’t exactly scream “home”, so I was glad to have it out of sight. The downside here, it that the bed is over the cab. That means that the area under the bed gets VERY cold. I combat this with closed cell foam. The camping section of any decent department store will have closed cell foam camping mats for quite cheap. I have a partial layer of that foam under where my torso lays. I should layer the whole surface, but I’m doing this as cheap as possible. On top of that is a self inflating camping pad that serves as my mattress.


The interior space of the camper is heated by a propane furnace controlled by my custom built thermostat. I try live as “green” as I can, but a camper is just not an efficient habitat to occupy in such a harsh climate. I do plan on building a very green and efficient small home some day, but until then I do my best with what I have. To make up for the lack of thermal efficiency, I keep the temperature low to save on propane. I’ve discussed this elsewhere, but I’ll recap it here. My base temperature is 40°F. This temperature was chosen a bit arbitrarily as a temperature that would protect against freezing. So it stays 40°F when I am away, if I forget to turn it down before I leave, the motion sensor will do it automatically after an hour without motion. I also set it to 40°F when I go to bed. I sleep quite well there, of course, I have an appropriate sleeping bag. Getting up in the morning in the cold was pretty tough last year, so this year I programmed a delay function into the thermostat. Now, the heat comes on before I wake up. When I’m home, I keep it to 60°F. I splurge on 65°F once in a while.

Laugh not, for thy poncho conceals fatal weaponry.

Some people find 60°F to be pretty chilly for an indoor temp. You may agree, and you’d be right. But since each of our bodies is a personal microclimate, it’s easy to rectify with clothing. I always wear a thermal base layer (we call ‘em “Long Johns”). I wear warm fleece sleeping pants, and either a sweater or a hoodie. I also wear a hat and gloves inside. I tend to favor light weight touchscreen gloves so I can interact with utensils, mobile devices, and my Apple Magic Mouse, which is touch based. My hat is one of the ugliest I’ve seen, but it’s made of thick fleece, which has unbeatable heat retention. A fleece throw blanket comes in handy often. One of my most effective garments is a DIY poncho (or serape depending on who you ask). I took a thick fleece blanket, and cut a head hole in the middle.  Draped over me, it keeps me warm while retaining the use of my hands. It is WAY more effective than draping a blanket over you. In addition to warming you front and back, the covering of the shoulders makes a great difference in holding body heat. I’m not going to win any fashion awards here. I bet I’d look more stylish in clogs and Hammer pants. In fact, in a mash up of two Clint Eastwood  characters, I’ve named this look “The Hobo Josey Wales”.  Hey it works. Function over fashion, always!

An effective toe warmer.

I’ve just begun experimenting with a small personal ceramic heater. I have avoided using electric heat as a primary source because I currently only have about 15 amps I can safely use, and a heater would take most of that. This small heater uses only 250 watts, and cost me $10. It has zero ability to affect the temperature in the camper as a whole, but is has a purpose in warming hands or feet that tend to get cold easy. I can take the temperature down to 50°F and this heater takes the edge off the cold, as long as I’m mostly stationary.

I also have a portable “Buddy” from Mr. Heater as a back up. It uses 1 pound propane canisters, and I can deploy it in a pinch if need be. It’s not suitable for long periods as it puts a lot of moisture in the air. It’s also old, and it doesn’t seem to want to run for long periods, anyway. It’s nice to know it’s there in an emergency, though.

There are a couple of challenges I face. One is convection. As the camper loses heat to outside it creates a movement of air that feels almost like a draft. This makes it feel colder than it actually is. I also have small humidity issues. Since I have buttoned up the camper as much as I can, I have affected the ventilation. With less ventilation, I lose less heat, but I retain moisture. It’s not a lot, but it’s enough. Cold spots can condense the moisture (sometimes into frost on the metal door and window frames). If I don’t pay attention, the moisture can create black mold. The answer would be a ventilation system that retained my heat (like an energy recovery ventilator), but those systems are beyond my scope and price at the present time. I do plan on incorporating such devices when I build my own place.


At the end of the day, the biggest step in overcoming the cold (or anything) is our mind. I believe comfort is largely an illusion (I’ll be writing a post about that). We can choose to adjust our comfort levels, and learn to be comfortable in situations that were previously not so. As long as the condition is not life threatening, comfort is largely subjective. Once we learn to take our perception of comfort down a notch, our perception of luxury falls with it, and we can really begin to appreciate the little things.

Additional Pics:

Plexi against a rubber gasket. Decent storm window.
Insulated fridge cabinet.
Insulated rear storage.
Completed cab wall.
Extra insulation around the bed walls.

My First Garden

Nothing to see here.

The idea of growing a garden had crossed my mind on and off for a quite few years. It was always something I would “get around to” someday. It was always, “maybe next year”. This year, I finally took the plunge. I didn’t get started until late in the season. It was almost the end of July when I finally got my seeds in the ground. I figured I would just get what I could out of it. Even with total failure, at least the hard work of prepping the land would be done for next year.

My late start ended up being a bit of a blessing. We got an impressive amount of rain early in the summer, and a lot of my friends lost their early plants as a result of drowning in puddles or being washed away. I picked a spot near the camper, but far enough away to avoid the shade of some tall spruce trees. My crop selection was as follows; corn, carrots, beans, romaine lettuce, basil, and cucumber. I decided it was too late to attempt tomatoes or peppers.

I thought about just tilling the grass into the soil, but decided I would have a cleaner, less weed riddled plot if I removed the sod. This was a back breaking process. You may notice a tractor in the background of the pictures, but this is not my tractor. It belongs to my aunt next door, and I certainly could have used it, but I guess I wanted the whole “frontier living” experience. At one point, my dad drove by on the tractor while I was lifting sod. “You know we have a tractor?”, he asked, as though it had slipped my mind. “Well, I have a shovel.” I answered. I felt like I might never get all that sod out, and I had to stop for a week when my back had had more than enough. I let him try to help with the tractor, but the attempt to lift the sod with the forks was making more of a mess than helping. This is not a farm tractor, and they own no farming attachments. So, back to lifting it out one square at a time.

Tilled and waiting for seeds.

Eventually, I was ready to move on, and my neighbor, Dale, came over with his tiller. I fixed his recoil in exchange for use of the machine. I had let the sod chunks dry out so I could shake the usable soil from them before carting them away to compost. I even sifted out an impressive rocks, crawling on my hands and knees with a screen. I figured this was worth doing right, as failure meant waiting until next year to try again. The planting was a fast and simple process, though the carrot seeds were so tiny and difficult to handle that I worried they were planted too dense.

And then there was food.

Next was the waiting game. I have worked on my patience a lot, and this was proof that the work has paid off. But once I started to see life, it took off quickly. It was an impressive display of earths majesty to watch this unfold. The amount of growth from one day to the next was impressive. On days that I pulled out weeds and churned the earth a bit, the growth was just astonishing!

It wasn’t long before I was enjoying lettuce, with cucumbers shortly thereafter. The basil took quite a while to show up, and it was a small leaf variety that was difficult to work with in cooking. Eventually, the carrots were getting to an edible size, and I was impressed that the overcrowding wasn’t more of a problem. I’m sure they would have done better spaced out more, but I had a high percentage of good size carrots that grew deep into the soil. The beans were struggling, with no signs of flowering, and the few corn seed that took were having trouble standing in the winds I was getting. I’m pretty sure crows go to some of the corn seeds.

I did some pest control. We had a family of ground hogs next door, and raccoons are common. I set out a large live trap, eventually catching both groundhog parents and the child. All of them were driven away and reunited elsewhere. I got one raccoon as well.

I learned a lesson about beans. There are pole beans, and bush beans, and I did not know there was a difference. I figured the pole was a personal choice, allowing you to grow vertically and therefore tighter, much like a trellis for cucumbers. I eventually came to this realization, and installed poles. At the end of the season, the beans had climbed the poles and started to produce beans, but it was a bit too late.

What’s up, Doc?

So the beans were a wash, the basil was not a good variety for my purpose, the corn didn’t have enough time to grow, and only half of my cucumbers took. But, the cucumbers that took were EXCELLENT! The lettuce was a huge success, I was eating lettuce for weeks, even after a few frosts.

16lbs in total.

The true triumph was the carrots! I was picking a few here and there as they were ready. I brought quite a few into work to share with coworkers. Finally, at the end of the season, I pulled the rest up. The last harvest was 16 pounds worth. I canned 8 pounds. I would have done more, but I ran out of mason jars, as did the grocery store. The remaining 8 pounds I ate and shared. They lasted for weeks in the the fridge. And now I have jars of carrots that could last me for most of the winter, though I plan on giving many out for Christmas.

My own grocery store.

Now that there’s about 3 feet of snow on the ground, I’m shifting my attention to a new endeavor – an indoor hydroponic operation, that will eventually include a food computer. What is a food computer? Well, you’ll have to keep coming back here to find out…

Enter, The Food Computer


openaglogowhite_small2The coolest part of my trip to the White House was the discovery of the Food Computer. This device is the small scale prototype for a much larger project taking place a the MIT Media Lab. It’s the work of Caleb Harper who is behind MIT’s Open Agriculture Initiative. The project has several aims. Ranging from educating kids about food (where it comes from, how it grows, etc…), researching how to grow better food, and of course, feeding people.


Caleb’s PFC hardware guts

Enter, the Food Computer

The PFC (Personal Food Computer) is the open source hardware and software system being developed to help change our food future. In layman’s terms, it is a system that controls all aspects of the plants environment over its whole lifespan. Since different plants have different requirements, the system uses a “climate recipe” (which is simply a series of instruction for the computer) designed the plant in question. Basically, you plant a seed (or a started seedling), select the climate recipe, and press play. The machine will maintain the right temperature and humidity, it will provide the proper nutrients, it will cycle the lighting, it will do everything the plant needs. Then you eat it.

My Raspberry Pi and Arduino getting set up for growing.

How does it work?

So, as you might expect, it’s a bit more complicated. There is quite a lot going on under the hood. Here’s bit of geek-speak; It uses a Raspberry Pi as it’s brain, and an Ardunio Mega for the heavy lifting. The Arduino controls the mechanical bits like pumps, and relays, and monitors the array of sensors. The sensor data is passed to the Pi where the climate recipe can tell the Arduino when to perform necessary functions. For example, a pH sensor tells the system when to raise or lower the pH, and a peristaltic pump can supply a solution to make that change. It also does this with the nutrient solutions electro-conductivity, among other things. You can control CO2, Dissolved Oxygen, and nutrient solution temperature. So, the pant receives everything it needs, precisely when it needs it, (ideally) without human intervention.

Caleb’s PFC at SXSL growing basil

As we speak (December 2016), the PFC V.2.0 is being released. The original version was more difficult and expensive to build. V2.0 is working to change that. It’s an alpha release right now, so there is still work to be done to make it as cheap/easy/accessible as possible. Being open source, anybody can download the plans and the software to build one. You can contribute your ideas to make it better. The release of the plans is an ongoing process, so don’t expect a simple plug and play approach just yet.

So where is this headed?

As the PFC becomes more accessible, more people will build them (including schools, some are already doing so). The plan is to make kits available for purchase to simplify the part sourcing. As the user base increases, a database of climate recipes will amass. You can download a recipe that suits your needs, or you can experiment and upload your own results for others to use.

Whats really exciting is the opportunity for knowledge. Caleb described to me how his team freeze dries the resulting plants and places them in a spectrometer to see the nutrient/chemical break down. They can change growing variables and see the direct results of those variables on the plants chemistry. They can stress the plant in very specific ways (light or nutrient starvation, bacteria introduction, pH/EC shifts) to see what chemical defenses it puts up, and how that changes the nutrient/chemical properties. These things affect the flavor, the nutrition, the shelf life, etc… The best part is, IT’S ALL REPEATABLE. A good result can be downloaded and recreated by anyone, anywhere, with a PFC.

Food Servers and Beyond

The PFC is admittedly small. You aren’t going to feed your family with it. It’s footprint is about 3 feet wide by a foot and a half deep, and it stands maybe 3 feet tall. It could fit on a counter or a small table, and can grow about 4 small plants at a time. But the PFC is simply the home version of what MIT is really building at OpenAg. The PFC is like a test platform to get us geeks involved and improve the system. The lessons learned in the small scale are being put to use in Food Servers. The servers are built in shipping containers, using the same hardware and software. This is all happening now, in the new lab that OpenAg has just opened. The next phase is the Food Datacenter, which scales the project to warehouse size. The scalability is built into the project, so it’s instantly scalable without having to be reimagined.

Servers and Datacenters can be deployed in various ways. They have a home in climates that don’t support standard agriculture, they have a home where food is scarce and people are hungry. In America, they have a home in the city. According to the census bureau (in early 2015), 62.7% of our population lived in the city, and cities make up 3.5% of our land. The food to feed our population often travels an enormous distance. The urban agriculture push seeks to change that. We see more city gardens and roof gardens, but it’s not enough. There is talk of entire floors of skyscrapers becoming farms. This is where food computers can play a role.

So what is my plan?

I am WAY into the whole food computer concept, and I hope to contribute to the initiative ASAP, but I am financially challenged. They are working hard to make a system that is affordable to build, but obviously this system will presumably lack some of the higher tech solutions that MIT is deploying in their own systems. I’m keeping my eye on their progress, and buying what I can, when I can, in order to deploy a PFC. But I’m not spending my time idly, I’m building my own hydroponic system.

Armed with a prime directive of feeding myself, the PFC is taking a necessarily secondary position, but I’m keeping it’s spirit nearby. The systems I’m designing to control my growing environment are taking their cues from the PFC. I’m trying to keep my equipment selection to PFC compatible options. Eventually, I hope my system will run on the food computer software. In that sense, I’m skipping the PFC and going straight to the food server, though I do plan on having a dedicated PFC as well.

I already have about 80% of my hydroponic operation setup, and hope to be starting seeds by the end of the year. Naturally, I will be writing about the journey as it unfolds.

Keep making stuff (and remember, growing food counts as making stuff!)




SXSL – Mr. Dubs Goes to the White House

white_houseIf you’ll allow me to brag for a moment, I’ll tell you about my trip to the White House. During the first week of October 2016, I had the honor of spending a few days in and around the historic establishment. Now, I’m no journalist, and I prefer to keep this blogs focus on my lifestyle not my life. The details of my day to day personal life will rarely grace these pages. But, the impact of this experience has helped shape my future, and I need to share this in order to tell you what comes next. And so I present my White House adventure…

The occasion was a festival called South By South Lawn (SXSL). Most people have likely heard of the South By Southwest (SXSW) festival, which is a longstanding hotbed of great music and films. But, it also features panel discussions on some of the most important topics for the culture of today, and of tomorrow. After President Obama’s visit to SXSW in 2016, the White House team decided to capture that spirit on the South Lawn.

I’ll refrain from “reporting” on the event, you can read about it straight from the White House website. There is also a great photo spread on the White House Medium channel. (shameless plug: I’m in the last picture, preparing close out the day by watching the premier of Before the Flood).

signThe day began with a bang, as I got to help the one and only Adam Savage (MythBusters, set up a SXSL sign he had helped create with a team of Makers from Baltimore. You can watch his build video here! And, here is a time lapse video the White House crew made of us setting it up.

adam_selfieIn my previous life, I had the pleasure of meeting an incredible number of famous folks, but none more gracious than Adam. Our conversation covered topics from difficulties in making 100% whole wheat bread to similarities between tempering steel and conching chocolate.

The event was graced with a number of exhibitors, many of whom were involved in food based initiatives. These were of particular interest to me, as I had just harvested my first successful garden (more on that later), and was keen on growing as close to 100% of my own food as possible.

Among the attendees was Green Bronx Machine and Kitchen Garden Laboratory. In a world where a staggering number of children don’t know where food comes from, these two initiatives are teaching students about food and nutrition, even in an urban agriculture setting. Together, they were preparing incredible food picked straight from tower gardens.

The Global Alliance for Clean Cookstoves had an incredible selection of stoves on display. Solar stoves, solar ovens, alternative fuel options, and stoves that can charge electronic devices while they cook. In less fortunate parts of the world, many are forced to cook with wood indoors, causing millions of deaths from smoke inhalation. These stoves offer safe and efficient options for the 3rd and 1st world alike.

pfc_1But perhaps the most inspiring part of the day was my visit to the tent of the Food + Future CoLab, a joint venture between IDEO, Target, and the MIT Media Lab. I met Caleb Harper, who introduced me to his Food Computer. Caleb runs MIT’s Open Agriculture Initiative out of the Media Lab.

You can expect dedicated writing about the food computer, but here is the gist. It is essentially controlled climate growing. This is not new in and of itself. Greenhouses and hydroponic growers have long since employed such techniques. You can even buy commercial machines much like Caleb’s food computer right now, but you will spend thousands to grow very little food, and be subject to proprietary technology in a “black box”.


In traditional MIT spirit, the food computer is open source, so there is a much bigger community picture at play here. The computer uses a “climate recipe” to control all of the variables. If you devise a successful climate recipe, you can share it with the community. Likewise, you can search the database to see what recipes are available, and download one that suits your needs. Plant a seed, press play, wait for food. All of this community effort will enhance the hardware design, software design, and climate recipe database. The result is a system that gets easier and cheaper to build and operate, and most importantly can be scaled up. There are already Food Servers (shipping container sized food computers) and plans for warehouse sized Food Data Centers. These systems can be deployed in cities to provide a local food source, or in areas/climates where food is scarce. I’ll be writing more details about this as I engage in this initiative myself.
pressSo my trip yielded some much needed inspiration and direction, and my tour of the underbelly of the White House machine was unprecedented. I’m not sure if the experience is a testament to how cool I am, or how cool my friends are, but I’m quite certain it’s the latter.

The Water Whisperer

shurflo_boxIf you use a 12 Volt RV style pump for your water, you need to install one of these RIGHT NOW!

It’s called an Accumulator tank, and it is much like the bladder tank you’ll find in a typical residential water system that is fed from a well. It’s purpose it to maintain pressure in the system, and it provides a number of wonderful benefits.

I have described my water system before, in case you want to get up to speed. I use a demand water system. The pump has a pressure switch that turns on when the water pressure drops. So basically, when I turn on the faucet, the pressure drops causing the pump to turn on and supply water. When I turn the faucet off, the pressure quickly builds back up, and the pump turns off. Thats simple on paper, but in practice it has some drawbacks. Chiefly, you cannot turn the water on a little. The faucet has to be wide open, if at all. Otherwise, the pump suffers from pulsation. It’s reminiscent of “water hammer”, but its different. When the water flow is restricted by a semi-open faucet, the pump turns on and off rapidly as the pressure rises and falls over and over again. It’s annoying, and its bad for the pump. It also makes using a sprayer difficult. My sprayer caused pulsation until I modified the mesh outlet. With this tank, that would not have been necessary. Having to run the water wide open means a lot of water gets wasted while rinsing dishes or washing hands. Not to mention the mess of water around the sink that results from the impetuous flow.

Enter the accumulator. It is a accumulatorpressure vessel that contains a bladder that is filled with air to 30 PSI. When water is pumped in, it compresses that bladder, increasing the pressure to a point that tells the pump to turn off. When I open the faucet, the initial water pressure comes from the ACCUMULATOR, not the pump. This means that I can turn the faucet on as little or as much as I need to. As the water leaves the accumulator, the pressure eventually drops until the pump turns on to maintain the flow of water. When the faucet is turned off, the pump will continue to run, filling the accumulator until the bladder provides enough pressure to turn the pump off. It’s a lot like a capacitor, but it stores hydraulic energy as opposed to electrical. And, much like a capacitor will filter or “smooth” out a signal, this smooths out the water flow.  It took a moment to get used to, as the pump does not turn on right away with the faucet, and it runs for a few seconds after you turn it off.

It comes pre-charged to 30 PSI. It has a standard air valve, should you need more pressure for your particular pump, or if you need to replenish pressure lost over time. It came with a coupler, so installing it right next to the pump required no additional fittings or hardware. They are commonly available for $40-50. In my humble opinion, this is a must have item. I wish I had done this sooner.


Thermostat Update V2.0

img_1355UPDATE: Version 3.2 is live. Read about it HERE.

This is just an update on some thermostat happenings of late. I recommend reading the original post to get up to speed.


I have mentioned elsewhere that I maintain a temperature of 40°F overnight while I sleep. I find that to be a great temp for sleeping, and for saving on propane. It’s a bit rough for getting ready for work in the morning, though. I tried keeping it at 50°F overnight when I started getting a steadier income, but realized just how much propane it takes to get an extra 10 degrees. I decided to add a delay function to the system. I did not want to futz with the complexities of a programmable timer circuit, especially since the RTC chip is not known to be super accurate. I decided a simple delay was best. It’s just a button that increments a delay time. I set the delay for, say, 7 hours, and go to bed. When I wake up the furnace will have been running for about 30 minutes, and its good and toasty.



I had always planned to introduce the thermostat to the Internet of Things, and finally made that happen this weekend. I’m still debating on my final approach, but for now, Ive gone with the Photon from Particle.  It proved to be a REALLY fast and SUPER EASY platform that saved me a TON of headaches and development. No hosting a local web server, no port forwarding, no dynamic DNS. Almost plug and play! I have a lot more work to do. The interface is virtually non-existent besides a simple on/off. I want to get some feedback from the system, like temperatures and runtimes. The problem is the difference in logic level. The Atmel chip uses 5V logic, the Photon uses 3.3V. Luckily, 3V is the threshold for the Atmel pins to go HIGH, so the Photon CAN trigger the Atmel chip. But I can’t safely send any info from the Atmel to the Photon without damaging it with 5v. I’ll be getting some 74 series level shifting DIP chips soon, but until then, I going build a simple voltage divider to tide me over.


My eventual plan is to have my Raspberry Pi operating as the brain of the camper, controlling all the sub systems though a web interface. I’ve gotten as far as running Apache and PHP on my Pi, but its the old (orignal) Model B, and I think I’m due for an upgrade. I’ll write again when the web interface is complete. Keep making stuff!


The Jedi Light Trick


I have grand schemes on setting up a solar powered LED lighting system in the camper, but until the money and motivation magically align, i’m just making it up as I go. All of the light fixtures in my camper are old and cracked and falling apart. The central most light fixture died completely recently, and I made do without it until now. Years ago (January 2012) I built an infrared light switch (programmed with Arduino and housed in an Altoids tin) to control some halogens I no longer use. I stumbled across that old circuit today and decided to repurpose it. I wrote about the original build back then, if you care to read the details. It has the schematic (EagleCAD) and Arduino code attached if you want to build your own. My dad (who is obsessed with LED lighting) had just given me a neat 12V LED array to check out. He is always finding cool lights like this on eBay.

The circuit is powered with 12v because it uses a 12V relay, which was all I had on hand the day I built it. I’d like to redo it with a 5V relayimg_1346 since that is all the Atmel chip needs to operate. 12V poses a couple of problems. First, since the chip requires 5V, I have to step the voltage down (with a 7805 in this case) which is not very efficient. Second, the Atmel chip cannot switch the relay on its own. The voltage/current is just too much. So I had to use an NPN transistor to switch to relay on. The chip switches the transistor, which in turn energizes the relay. I wasn’t really in the mood to re-solder a different relay in, and then have to re-write any code, so I left it as is for now.

img_1354It’s all programmed with Arduino. Its quite simple code wise, with about 40 lines of actual code. It really just monitors the iR detector for light reflected from the emitter (from a hand for example), and toggles the relay on and off when it sees it. The lights ground is switched via the relay. It was tricky to get the sensitivity right, as I recall. I thought I was going to build a ton of things into Altoids tins, but as yet, this is the only one.

The switch is located near the entry door. When I come home in the dark, it just takes a Jedi style hand gesture and the centrally located light will illuminate. I may be up to some solar and lighting projects in the near future, so stay tuned. Enjoy the included video, and see the link above for the circuit details from the original build post.




Keeping Warm, Part One: My Thermostat



See Version 3.2 HERE

See Version 2.0 HERE


Now that the northern Maine temperatures have finally crept above 40°F on a regular basis, I decided it’s time to talk about how I managed to stay warm this past winter. I’d like to start things off with my thermostat. There is a lot to say here, so i will devote the whole post to it. Other cold beating techniques will be discussed in part II.

Why Build a Thermostat?

“You know, you can buy a digital thermostat at Lowes for $17?” I got some version of that response from almost everyone I spoke to about my idea of building my own. The thermostat that came with my camper was working just fine. I didn’t need to build one, I wanted to build one. I take great pleasure in making things that solve a problem, and my DIY thermostat had the potential to solve a number of problems.

The first problem it solved was saving me $17. Everyone was right, I could just by a thermostat. At the time, Lowes had a basic digital Honeywell thermostat for $17. At the same time, I was broke, and $17 buys an epic amount of ramen. My geek stash had all of the bits and pieces I would need already, so there was no expense incurred in this project. The cost of propane was a big concern for me. I decided I needed to maintain a minimum of 40°F. Warm enough to ensure my water didn’t freeze, but cold enough to conserve on propane. My analog thermostat only went as low as 50°F, and “OFF” was so close to 50°F that I could never be sure if it was on 50°F of off completely.

Some higher tech solutions were deployed for extra geek cred. I knew I would forget to turn the temperature down before I left for work sometimes, so I used an infrared motion sensor to tell whether I was home or not. I wanted to gather data regarding how long, and how often my furnace ran. It would give me a gauge on how many hours of run time I could get out of a tank of propane. I used a data logger to write data to an SD card for later science.

How it Works

I’m going to try my best to keep it as layman as possible for the electronically uninitiated, but I will include some gritty details later to appease the electron junkies in the pack. This whole system is run by a microcontroller. Think of it like the processor (CPU) in your computer or whatever device you’re using to read this right now. All of the code that makes up the software you use is just a series of instructions that is read and executed by the CPU. So, I write some code, load it onto the controller chip, and it runs the program over and over. In this circuit, there is a temperature and humidity sensor. The controller constantly asks the sensor what the temperature is. I set my desired temperature by using two buttons to bring it up or down. When the temperature reported by the sensor is lower than the temperature I set, the code turns the furnace on. It’s more complicated than that, but that’s the basic idea. The controller also uses the infrared sensor to check for motion. If it sees no motion for an hour, it goes into a 40°F standby mode. Any time the furnace turns on, that event is logged to the SD card, including the time. When the furnace turns off, that event and time is logged as well. The times are subtracted from one another to determine how many minutes the furnace ran. That time is added to a cumulative run time.

The Geek Stuff

Here is some jargon. Feel free to skip this paragraph. This was programmed using the Arduino environment, but in a standalone arrangement (the controller runs on its own, without the support of the programmer). I’m using an older Sensiron temp/humidity sensor, and Adafruit’s Datalogging Shield. All of the pertinent info is written out to a Parallax 2×16 LCD. The furnace turns on with a contact closure, which is achieved by energizing a 5V relay. There is a mix of both i2C and SPI serial communications. The Sensiron chip uses i2C, the data logger uses BOTH protocols (i2C for the onboard RTC chip, and SPI for the SD read/write operation). I’m happy to share my code with anyone interested, but I’m not sure how compatible it is with more modern temp sensors.

thermologThe Numbers

I lucked out, because we had a very mild winter. The lowest temperature I saw was -16°F  (our wind chills brought us down to -30°F once in a while, but not often). I only spent $300 on propane all winter, and I was expecting much more. Each 20lb propane tank gave me over 30 hours of burn time depending on how much I was cooking (the stove uses the same propane). The spreadsheet on the left is a screen grab of the CSV file as it is written to the SD card. By keeping the temp at 40°F while sleeping or when I was gone, I saved a buttload of money. It took an exceptional amount of additional propane just to try to maintain 50°F overnight. Sleeping at 40°F was quite pleasant. A good sleeping bag is the only prerequisite. Getting ready for work in the morning is NOT quite so pleasant at 40°F, but I wasn’t expecting this to be easy.


What I really love about this process is the troubleshooting aspect of problem solving, and what I learn as I navigate it. Reality never behaves the way our ideas do on paper, and the act of wrapping our brains around those surprises teaches us a lot about the world. Sometimes, something seemingly so simple is actually far more complex. Sometimes, very complex things have very simple answers. I assumed that my code could say “when the temperature hits 60°F, turn the furnace off.” But in reality, the temperature fluctuates a lot as the room seeks equilibrium. The furnace would turn on and off several times while this happened, and it was hard on the electrical system. I had to write code that held the furnace on through a “buffer” period to let the room stabilize, and that minor change took more thought to engineer than the whole system did.

When we finally hit a warm spell, my furnace died! The timing couldn’t have been any better. It would have been an outright calamity even a week before. I had just made $80 helping my Mom out, and the part I need to fix the furnace happens to cost $80. Oh, how kind the universe can be when I don’t get in the way. In part two, we’ll talk about clothing, and the dynamic nature of human comfort.

UPDATE: I’ve added some features! See Version 2.0 HERE