Actually it happened last week, and we blew past it without even noticing which point rolled it over. Officially, to date, Safecast has collected and published over 10,000,000 individual data points. That’s a huge milestone for us, and when you consider that it took us 6 months from March 11, 2011 to collect our first million, and we were just passing 4,000,000 towards the end of 2012 – this is shows how our collection efforts continue to ramp up.

Obviously a lot of this is due to our incredibly dedicated volunteers. Earlier this year one of our volunteer teams, GLC, broke 1,000,000 measurements they had collected themselves which was terribly exciting and with the recent release of our bGeigie Nano Kit which allows anyone to use the exact same hardware and system we do to collect and submit data, we only expect this to continue to speed up. We’re celebrating this milestone in Aizu at the Eyes, Japan office hosting a nano-build-a-thon where we made more nano’s in a 48 hour period than ever before. More on that soon.

The above video is a hexacopter with an onboard bGeigie Nano taking radiation readings in flight and broadcasting live via wifi. It’s the result of the just finished week long Safecast hackathon that just took place in Cambridge, MA.

There were a number of reasons to focus on a drone during this hackathon. Of course drones are cool and exciting, so that helped to keep people interested. On a practical level there’s also a need for something like this that would enable us to take measurements in a location that would be too dangerous or just plain unreachable for people, such as a steep hillside or a contaminated area. We could also plot out a flight path and let a drone measure a huge field much quicker than a person might be able to navigate the area. Thinking about our data in relation to a drone also allowed us to consider some existing issues from a different perspective and tackle them with renewed vigor.

The concept of a Safecast Air Force – that is a modular drone platform with a number of interchangeable elements – was originally suggested by Ray Ozzie and and over the week Safecasters Naim Busek, Joe Moross, Pieter Franken, Steven Wright, Ariel Levi Simons, Haiyan Zhang, Paul Campbell, Anthony DeVincenzi, Samuel Luescher and I took it from idea to reality.

We started off with a prebuilt Hexacopter from 3D Robotics and then upgraded the motors and blades, as well as giving it a more robust DJI Flame Wheel Frame. With Ardupilot (an open sourced arduino based autopilot system) providing the brains and Safecast providing the payload, we built quite a full featured flying machine.

While this is certainly our flagship at the moment, we also looked into using the Parrot AR.Drone 2.0 Quadricopter as a prebuilt platform as well. We have a lot of work to do reducing weight of devices for that to work, but if we can prove a concept works on a more expensive design and then scale it back to a minimum viable product that easier for people to contribute to that’s an exciting prospect as well.

If we step back for a moment, this modular system becomes quite elegant. The drone is the “platform” but could easily be swapped out for a bike, a car, or carried by a person. The “sensors” for this proof of concept were radiation, but could also be swapped for air quality or anything else you wanted to monitor. We were using wifi to “upload” the data, but there are any number of other data transfer methods that could be deployed here. We’ll continue to develop this program and are excited to see how it helps spring board our other initiatives.

A handful of earlier test flight videos can be found after the jump.

Radioactivity in Inzai, Japan. 18 months worth of data.

Radioactivity in Iitate, Japan. 24 months worth of data.

A scan of two cities

While events at the Fukushima Daiichi plant have led to the common association of all of Japan with radiation we have collected enough data to show that large swaths of the country remain near background (Approximately 30-40 counts per minute). One example of this is the city of Inzai, which lies between Tokyo and Narita International Airport, and is 193km southwest of the meltdown site.  As the first graph shows background levels slightly above what is considered typical, but there is no appreciable change from the middle of 2011 to the end of 2012 in terms of radioactivity.

The next city in our study, Iitate, is about 38km northwest of the Fukushima Daiichi reactor site, and shows both more significant exposure and a noticeable decay curve.  What is notable about the decay curve is that a decay half-life can be estimated to reasonable precision with the best-fit exponential decay function.  From this method we can estimate the decay half-life for surface radioactivity to be only one year from the two years starting in the middle of 2011.  This is notable as the decay half-life for the two dominant radioisotopes, Cs-134 and Cs-137, are two and thirty years respectively.  This implies that there are additional mechanisms at work in Iitate which are moving radioactive material away from the surface, such as erosion and the deposition of new topsoil, which are accelerating the decay of measurable radioactivity at the surface.

The start of a larger analysis

Below is a series of radioactivity versus time graphs for eight locations across Japan over the past two years.  All of the data was taken from the Safecast public database with selection areas consisting of squares 2km on a side selected around a given GPS coordinate.

	latitude: 37.7608337N longitude: 140.4747282E Distance to Fukushima Daiichi reactor: 62km NW Start time: 5/5/2011  10:05:08 AM Estimated half-life: 1.0 years Stop time: 5/1/2013  9:32:00 AM Estimated half-life: 1.0 years Data link
	latitude: 37.4472222N longitude:141.0055556E Distance to Fukushima Daiichi reactor: 4km NW Start time: 9/24/2011  1:32:22 AM Stop time: 5/1/2013  7:35:37 AM Estimated half-life: 1.8 years Data Link
	latitude: 37.6791903N longitude: 140.7352474E Distance to Fukushima Daiichi reactor: 39km NW Start time: 5/6/2011  4:41:58 PM Stop time: 4/29/2013  8:03:56 AM Estimated half-life: 1.1 years Data Link
	latitude: 35.8323485N longitude: 140.1458154E Distance to Fukushima Daiichi reactor: 193km NW Start time: 6/26/2011  5:05:39 PM Stop time: 11/17/2012  11:04:28 PM Estimated half-life: NA Data Link
	latitude: 37.5131313N longitude: 140.3938904E Distance to Fukushima Daiichi reactor: 57km W Start time = 5/25/2011  3:21:34 PM Stop time = 5/1/2013  9:14:07 AM Estimated half-life: 1.4 years Data Link
	latitude: 37.4945855N longitude: 141.0006538E Distance to Fukushima Daiichi reactor: 9km N Start time: 9/16/2011  11:56:10 PM Stop time: 5/1/13 7:44 Estimated half-life: NA Data Link
	latitude: 37.2826405N longitude: 140.9934863E Distance to Fukushima Daiichi reactor: 16km S Start time: 9/24/2011  1:12:37 AM Stop time: 4/26/13 5:12 Estimated half-life: 2.7 years Data Link
	latitude: 37.4044283 longitude: 140.9833544 Distance to Fukushima Daiichi reactor: 5km SW Start time: 9/24/2011  1:28:22 AM Stop time: 1/1/2013  8:40:52 AM Estimated half-life: 0.6 years Data Link

Where to go from here?

All of the above decay curves were generated using uniform squares of four square kilometers in area.  While this decreases spatial resolution it is useful for gathering significant statistics for a given location.  Further analysis could compare the relationship between the area of a study and the characteristics of the decay curve.  Similarly, this first look doesn’t consider the geography of the location.  It would stand to reason that the topography, soil, and climate of a given location should have a noticeable impact on the rate of change in surface radioactivity.  Generally, as the number of readings increases over time, the significance of the analysis from any location should improve.

Global Map of Carbon Monoxide concentration.
Courtesy of NASA

Public Health
The impact of atmospheric composition on various respiratory and cardiovascular conditions has been heavily studied for decades. Starting with the work of the Environmental Protection Agency and U.S. health standards we get a focus on gases such as Carbon Monoxide, which has the nasty habit of blocking the absorption of Oxygen into the bloodstream, as well as microscopic particulates, which will slowly damage lung tissue especially as the particulate size drop below a millionth of a meter (About 1/200th the width of a hair).

Personal air filters from different cities.
Courtesy of TOTOBOBO

Environmental Interest
Cities have an impact on their local atmosphere beyond the composition of any one target gas which has also been of interest to everyone from research scientists to people trying to reduce their air conditioning bill: the urban heat island effect. This effect is quite easy to demonstrate by comparing the surface temperature of an asphalt parking lot and comparing it to a grassy field on a sunny day. Cities, being mostly composed of dry and non-reflective surfaces, tend to absorb far more heat than the surrounding countryside. The result of which has been associated with an increase in summer fatalities, increased power consumption, and shifts in local rainfall patterns. The evolution in these patterns can be better understood even by just monitoring the local temperature and humidity across an urban area.

Downtown Atlanta in infrared.
Courtesy Wikimedia.

Sensor Durability
While a number of target gases have been identified in our development work we do also want to deploy monitors which could run for years with little to no maintenance. For example, compact and robust sensors exist which can measure Ozone, Nitrogen Dioxide, Volatile Organic Compounds (e.g. Methane), and Carbon Monoxide. However, the sensors which could monitor Sulfur-containing gases such as Hydrogen Sulfide and Sulfur Dioxide, which are also associated with acid rain and respiratory ailments, tend to wear out over a scale of months.

Profile of a solid state Nitrogen Dioxide sensor.
Courtesy of SGX Sensortech.

These criteria, coupled with a need to run these sensors in a small volume on with a lower power consumption, leads to our current list of metrics for Safecast’s air monitoring efforts:
Temperature, humidity, Carbon Monoxide, Ozone, Volatile Organic Compounds, Nitrogen Dioxide, and particulate matter of diameter one micron and above.

Most importantly, the nano is a fairly simple kit comprised of readily available off the shelf parts. If you know how to solder (or want to spent 10 minutes learning how) you can build the Nano Kit in an evening, and be Safecasting the next day. You can take individual spot readings, or attach it to your car and drive around collecting geotagged radiation data that can be uploaded to Safecast via our API upload page. This is the exact same process we use. The design (hardware and software) is open source (just like all Safecast projects) so you are invited to hunt down each part on your own, but to make things simple we’ve teamed up with Medcom to provide a kit that you can build yourself. The cost will be $450 and they will be selling them on a first come first serve basis in batches as the kits are produced. If you want one, fill out this bGeigie Nano interest form and someone will follow up with you in short order.

More photos and technical details after the jump.
[All photos by Pieter Franken]

Technical Specifications:

- Three systems in one: bGeigie, xGeigie and iGeigie:
- bGeigie mode – mobile radiation sensor with display indicator in CPM and µSv/h, number of satellites locked, height (m), distance traversed (km), total duration of measurement (h:m) and time stamp (dd:hh:mm:ss)
- xGeigie mode – geiger counter mode (no logging) with display indicator for uSv/h dose-rate (Cs137), max dose-rate, dosimeter, Bq/m2 display (Cs137), time stamp and Alarm LED
- iGeigie output – iPhone compatible output for Safecast iOS app. iPhone app shows dose rate and can upload data realtime to Safecast API.
- Sensor: LND 7317 2” pancake GM tube with Medcom iRover HV supply; capable of measuring alpha, beta and gamma radiation
- Modular design – main unit can be taken out of case to use as surface contamination survey meter
- High quality GPS receiver with external booster antenna connector
- Wireless option – bluetooth, 802.15.4 or Wifi supported through Xbee socket – send data wirelessly to bGeigie Ninja or smartphone (Experimental; wireless components not included in kit)
- Blue Indicator LED for every nuclide detected (with cool afterglow)
- Red Indicator LED for “recording” (bGeigie mode) or “alarm” (xGeigie mode) indicators
- Orange indicator LED for charge status
- Battery status indicator on OLED display, with low Battery alarm.
- Function button (user assignable)
- Buzzer (can be switched off)
- 2000mAh battery for approx. 40-hour nonstop operation in bGeigie mode. USB chargeable.
- Memory: 2Gb SD micro card (included)
- Hot switch between bGeigie and xGeigie mode (in xGeigie mode recording is paused)
- Many parameters configureable through config file on SD card (e.g. user name, conversion factor for µSv/h and Bq/m2, time interval, etc)
- OLED display: 128×64 high contrast, two OLED display sizes supported
- Realtime clock
- Watertight, shock resistant Pelican 1010 micro case in Yellow or Black.
- Carry strap and hook attachment (for car, cycling, walking, airplane, etc)
- Fits into “Topeak” Bicycle top bar case for us on road bikes (not included)
- Dual CPU: Atmel, Arduino. Open-source software.

*This is a kit and we’re always modding things so the above may change any any moment without advance warning.

Want one? Fill out the bGeigie Nano interest form!

We got quite some inquiries as to what is the right time to donate to Safecast to have Global Giving match your donation 200% on March 11th, expecially in which time zone.

Well, the 200% matching is as as well as per Japan Standatrd Time (JST) and Eastern Daylight Time (EDT). So:

The 200% Match Day will run on March 10th, 2013 from 11:00:00 AM EDT (March 11th, 00:00:00 AM JST) to March 11th, 2013 23:59:59 PM EDT (March 12th, 12:59:59 PM JST)

So, your (tax deductable) donation is tripled on March 11th and a great opportunity to support Safecast in measuring the planet for radiation and – coming soon – air polution!

CLICK HERE TO DONATE NOW

THANK YOU!

Saw this after March 11th? The campaign runs till March 15th, 2013 where Global Giving is matching your donation 100% and we’re really happy to receive any donation after the 15th as well!

In case you had not heard about this campaign to support Safecast – here are the details:

Our friends at Global Giving did this last year and it was incredibly helpful for us, so they’ve decided to do it again. From March 1st to March 15th they will be matching donations 100%, and on March 11th they will match 200%! The trick is there is a limited amount of matching funds available so if they are used up before the end of this campaign then matching stops. What this means is if you’ve been considering making a (tax-deductible) donation to Safecast, doing it now multiplies your impact greatly. Here’s the link to donate. You can also follow along and see how the matching program is going using this leaderboard . Thank you so much for helping us continue this work!

Internews, an international non-profit formed in 1982 with a mission to empower local media worldwide, has been doing important and groundbreaking work in areas such as medial law and policy, expanding access to information, and delivering innovative media solutions. The organization trains media professionals and citizen journalists, hoping to increase coverage of vital issues such as conflict management, environment and health, women and young people’s issues, and to help advance policies for open access to information. We admire them and their work, and think we’re motivated by similar concerns.

That’s why we’re pleased to learn that Internews has highlighted the work of Safecast in an important new 53-page report, “Connecting the Last Mile: The role of communications in the Great East Japan Earthquake,” authored by Lois Appleby, who was a first responder after 3/11 with CARE International. The report was supported by the Swedish International Development Cooperation Agency (SIDA).

INTERNEWS website

Direct link to report

The report points out the good work that has been done by many other groups and individuals, and levels warranted criticism at the numerous failings of established media sources after the start of the disaster. It’s very forward-looking and positive overall, though, and very well-written. We couldn’t help but notice that the founding of Safecast made it into their timeline of key post-3/11 media developments!

We’re all the more pleased because we didn’t have any contact with Internews before the report came out, and they included us without our knowing it. We really didn’t see this one coming!

Jun Yamadera

The start of the project for YR-Design was an extension of building bGiegies in Aizu Wakamatsu. By being in Aizu, having build a few bGeigies for SAFECAST and being exposed to the GreenSmile project from Jun Yamadera (Eyes-Japan), it was a logical step to enter the project. Jun Yamadera first came to YR-Design with his, at that time current version, sensor, a big box behind a bicycle. The box contained a custom build Geiger counter and other sensors. It also contained a big battery to power the WiFi access router. Jun asked us to looking possibilities for modifying the design to make it smaller. At that time YR-Design could not commit enough resources and time to help out.

In November 2012 we could commit more time to the project and at the same time Pieter Franken asked us to help with building bGiegeNanoKit prototypes. We made two prototypes (breadboard and wired by hand).

Routing

Sensor bGeigieNano and bGeigieNanoKit

At the Safecast Hakathon in January, 2013, Naim Busek taught me how to program the Xbee’s (modules that extend wireless communications for Arduino). Although we did not get an Ad Hoc network going at that time, I knew it would not be too hard to do.

Bike sensor mounting

At the Hackathon I mounted temperature and humidity sensors on one of the bGiegieNano, but did not test/develop the software (see picture). Also I mounted the modified bGiegieNano, with sensors, on a nice modern bike that could display data or advertisements on the wheel with Money Electric Videopro8 .

Clif logo

Back in Hikone, YR-Design made the software for interfacing the wheel and sensors with the bGeigie. Temporally using the existing data string as a base. And extending the data string with temperature and humidity fields. We made the interface working on WiFi (Xbee WiFi in AdHoc mode) with an Iphone, so Jun Yamadera could use it on a trade show for Carbon Credits. Also the bike with sensors was used for the introduction of Clif bars in an event organized by Duco delgore with the logo displayed on the wheel.

A second bGeigieNano with sensors was made for another bike. The sensors for that bGiegeiNano were mounted with the expositor of the sensor at the bottom to prevent water entering the sensors. The bike was also showed at TV News of Fukushima TV