We’ve been talking and collaborating with awesome Drupal developer RJ Steinert for a few weeks, and I’m going to be talking with him tonight at Dorkbot’s Summer party about the data monitoring system we’re developing. It’ll be short, so don’t come just for us, come because Dorkbot is awesome!
DEQ permits Dirthugger
Dirthugger, a new Oregon composting company, just got their permit from the DEQ!. Congratulations!
sensors off the grid
I’m working on a 3.6v lithium ion battery charger based on the LT3652. more later, I just like how it looks in CAD.
What Do People Do All Day? FIELD TRIPS!
Tomorrow’s field trip day here in the Cloacina Bubble. I am fulfilling a life long dream of mine, visiting a wastewater treatment center. After spending yesterday reading about Portland’s 140 acre wastewater treatment plant I can not wait to see this $13 million a year operation at work. Considering the disaster that is water borne sewage, Portland’s plant is one of the best in the nation.
Here’s my rough draft illustration of the Columbia Boulevard Wastewater Treatment process. I’m looking forward to fact checking my drawing with the engineers in person tomorrow morning (and they are too!). I hope they appreciate the new acronym I came up with for Combined Sewer Overflow (CSO), I’m now calling it SIR (Sh*t in River). SIR has been the city supported system of waste removal since the beginning of Portland. In 1952 they set up a system of screens to keep large debris from piling in to the river and then letting sediment sink to the bottom before dumping it in the Columbia River. My goodness you’re thinking, what a fantastically fresh take on the Cloaca Maxima. The Cloaca Maxima, built in 500 A.D. was a pipe (minus screens) that led to a swamp nearby.
If anyone wants to join the tour it’s free and we’d love company. Photography permitted.
2nd Composter Finished
Rodent Resistant Composter – More DIY How To Projects
Our household has officially outgrown our gigantic composter. We’ve made some changes to the composter and shared it on Instructables.
major changes: Simple wire cylinder separates inner compost chamber from outer ring of woodchips instead of a cylinder AND a wire basket. The wire cylinder with the wire basket for compost allowed us to take the compost chamber in and out but it also created an air gap around the compost that cooled it down. Also, compost is way to heavy to lift out with a mere wire basket.
We’re not aerating this pile, because we’re not sure the aeration is really working that well. If the aeration was working we would see higher temperatures from bacterial activity near the vents but instead we see the coldest temperatures there.
and it’s smaller.
WTF Fire Marshall?
Type.
So imagine me in a beautiful old building built for casting, welding, and other heavy industrial processes telling the landlord that we’re looking for space for our design group which builds and designs prototypes out of plastic, concrete and wood. He says to me ”Oh . . . we mostly have start ups in the building.”
Ba-squeeze me? Apparently American start ups only make lines of code. And if you want to prototype your own designs you’d better move out of town. How is Portland’s economy going to be based on code alone? I can’t sit on, eat, or drink code. In fact you can’t even run code with just lines of code. What kind of economy our we looking for?
New Monitoring System: easier, wireless, more reliable
Now we’re getting somewhere! My previous networked temperature monitoring systems were a little buggy. My first temperature monitor had its cable chewed up by a rodent and needed to be reset frequently. My second prototype failed on restart, making it problematic in low-power situations (a known issue for the Arduino’s Ethernet Shield), and eventually the probe itself succumbed to moisture because of a failed seal.
My new system relies on serial communication between an Arduino and a Motorola C168i cell phone, bridging data to Pachube through Twitter, and sending an e-mail to my server as a backup. I really like this setup because it is reliable, cheap, and deployable in far more locations than ethernet or WiFi would allow. I picked up a C168i at Goodwill for 10 dollars (and another on E-bay for $12) and it costs me $5 a month to add to my T-Mobile plan. The system runs off a single 6-volt source, and I’m currently piecing together a solar/battery system to go completely wireless.
Weather-proof housings:
I picked up a $6 5-quart dry bag from my local sports store, and am using that to house my arduino and cell phone. It rolls down on the cables, and is a great solution to the weather-proofing electrical connections. My sensors are connected through 1/8″ mini stereo jacks, because they’re ubiquitous. Tear them off of any broken set of headphones.
Rather than crimping the PEX tubing housing my sensor string, I’ve switched to screwing in 1/2” pneumatic fittings with some teflon tape. The stabbing end is filled with epoxy, and the cable end is sealed with several layers of shrink-wrap tubing and high-temp hot glue.
Code, and notes on communicating with a C168i:
The C168i has a wonderful feature that aught to be on all cell phones- you can talk TTL to the audio jack! It is presumed that internally the phone is a G-24 Lite GSM Module, and G-24 commands work on the C168i. On the forums there are some comments about sudden communication failures and dead phones. I think I’ve pinpointed the problem- The G-24 operates between 3.3V and 4.2V, and most USB devices, (including the Arduino) run at 4.6-5V. The phone is obviously running hot- when you plug a USB-mounted arduino directly into the C168i its screen brightness jumps and flickers. I knocked the voltage down to 3.7V by placing four 1N4007 rectifier diodes (two pairs of two , one facing each way) on each of the communication lines (RX & TX). I know it’s inefficient, but it’s quick, and only for when the system is being programmed/debugged.
Like this:
RX–>|–>|–RX
RX–|<–|<–RX
In the fielded system I removed the diodes and just run the power source at 6V, at which point the Arduino communicates at 4.1V.
Arduino code here
You will need SSerial2Mobile Library, New Soft Serial Library, Dallas Temp Library, and OneWire Library.
Compost Pile, Modified
We eliminated the inner bin our our compost about eight weeks ago. The air gap between the thick wire and mesh bin channeled too much heat out. Now we have just a 4′ diameter mesh pile full of wood chips, with a 24″ column of vegetable compost in the middle, and temperatures pushing 60ºC in the center. Our system is to load the compost roughly every month, letting vegetable waste build up in 5-gallon buckets, and then loading 10-20 gallons into the pile at a time. We shovel off the outer 12″ of wood chips, put vegetables mixed with paper & cardboard into the center column, and then cover back up with wood chips.
Speaking of Urinals… at Research Club, Tribute Gallery
Much thanks to Dustin Zemel!
Mathew Lippencott from Research Club on Vimeo.
Opening May 21 at AT1 Projects, LA
Things have been quiet here on our blog, because we’ve been preparing an exhibition. An essay/text and prototypes of ours will be featured in the Super/Prime Pavilion at Volume, AT1 Projects opening show. Super/Prime is curating a collection of works about transformations in process. We’re excited, but won’t be able to make the opening. If you’re around 3229 Casitas Ave, LA 6-10pm, stop in.
Others in the Super/Prime Pavilion:
Harry Gassel, Brendan Griffiths & Mylinh Nguyen, Riley Hooker, Gary Kachadourian, Brian Randolph, Steven Sarkozy, and Stacia Yeapanis