Safecast is a global sensor network for collecting and sharing radiation measurements to empower people with data about their environments.

Safecast Air Force (drone program)

May 6, 2013 12:30 May 6, 2013 12:30 May 6, 2013 12:30
 

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. Continue reading »

Monitoring Fallout Decay

May 3, 2013 06:00 May 3, 2013 06:00 May 3, 2013 06:00
 

One of the great utilities of the Safecast project is the ability to collect and analyze environmental data on an unprecedented scale. As Safecast passes the two year mark with collecting radiation data in Japan it is now possible to begin to look back over the changes in radioactivity across different parts of the country and see where this may all be heading.

Radioactivity in Inzai, Japan

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

Safecast data from Iitate, Japan.

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. Continue reading »

The bGeigie Nano Kit

March 22, 2013 05:17 March 22, 2013 05:17 March 22, 2013 05:17
 


The biggest limitation Safecast has faced in collecting data is the limited availability of our workhorse device, the bGeigie. The design works great, but it’s expensive (each one costs us about $1000) and time consuming (building one can take an entire week) which results in us having limited numbers of them to keep in use. We have way more people who want to drive around with bGeigie’s than we have bGeigie’s to be driven around. To solve this issue, we’ve created the bGeigie Nano, and thusly the bGeigie Nano Kit. As you might guess the Nano is a smaller form factor which makes it much easier to carry around and use, yet it’s even more feature packed than the original bGeigie. In fact many Safecast team members use the Nano’s exclusively now and carry them at all times, the compact size makes this incredibly easy to do.

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]

Continue reading »

Why is “Is it safe?” a hard question?

March 5, 2013 06:30 March 5, 2013 06:30 March 5, 2013 06:30
 

Top or bottom? Safe or not?

We are getting a lot of questions, both at info@safecast.org and through the Safecast group from concerned people – they all try to understand some aspect of radiation or another. And of course, many people ask similar questions, but without doubt the most often asked question is “Is [something] safe?” or a variation of it. Believe it or not, there is an answer in our radiation FAQ, but people keep asking ;-)

Recently someone who was planning to spend a few months in Kyushu asked about the contamination there. He had located some info on the radiation levels, and had concluded that currently the radiation level is higher than before 3/11. He asked if that was because of Caesium and Strontium contamination. In fact, he was comparing two different data sets that had been collected differently. I pointed him to DPNSNNE which allows users to download consistent monitoring data from all over the country and compare the changes over time. This data shows that aerial radiation levels in Kyushu are the same now as they were before the accident. As often happens in forums/mailing lists, once the question was answered, the discussion shifted the topic to “the difference in risk from Radon (naturally occurring) compared to Caesium and Strontium (anthropogenic)”. Immediately, data on half-lives (=time that it takes for the half of a certain amount of a radioactive isotope to decay) of Rn, Cs-137, Cs-134 and Sr-90 was put on the table as “evidence” and difference between half-life and biological half-life was discussed. So the question transformed into:

  • Since the (radiological) half-life of Radon is only 4 days, while Cs-134/137 has a biological half-life of 70 days (that is, half of it will be eliminated from the body in 70 days), and Strontium’s is 18 years, doesn’t that mean that radon is less risky than the others?

I had been thinking about this a lot and thought I might be able to explain it by example; an example that turned into this blog post (Here is a good place to thank Azby, Jam and everybody who read through my ramblings and pushed me to publish it). Continue reading »

GLC hits over a mIllion points!

March 2, 2013 19:48 March 2, 2013 19:48 March 2, 2013 19:48
 

Safecasters Joe Moross (far left) and Pieter Franken (far right), flanking GLC’s bGeigie team.

Global Survey Corp., which goes by the initials “GLC,” has been mapping Japan’s roads since 2005. Their data is used in many car navi systems, as well as for quite a few specialized applications. For instance, since 2009, the company has been measuring and mapping electromagnetic wave intensity to help customers optimize the placement of antennas for radio broadcast and wireless LANs, and to improve location accuracy for cell phone providers. So they have experience gathering invisible environmental data.

GLC website

Safecast was very fortunate to be introduced to GLC in August, 2011, by Prof. Tomo Furutani, part of Prof. Jun Murai’s team at Keio University, which also provided material support for the project. By early September that year GLC had a bGeigie in operation on one of their road-mapping vehicles, and soon asked for two more. The results they obtained in one year with three bGeigies were so good, we provided ten more units in December 2012. GLC recently passed the million-measurement mark for Safecast, which makes them our single most prolific data-gathering volunteer. We’re incredibly grateful for the time and effort they have put into collecting radiation data for us.

Hidenori Nakajima, the GLC liaison for this project, says, “After 3/11, so many people in Japan were in trouble, and our company wanted to do something for them. When we heard about Safecast’s bGeigie system, we were extremely impressed. Anyone can use it just by attaching it to their car. We’re very happy we’ve been able to help.”

A GLC mapping vehicle with bGeigie attached

GLC has told us that they try to cover every major road in Japan three times a year, and all the other roads at least once each year. Out of their fleet of 14 cars, 7 or 8 are on the road at any one time. With so many bGeigie-equipped vehicles constantly crisscrossing the country we estimate that GLC could soon be providing 500,000 measurements per month to Safecast. To that, we all say, “Hooray!”

Information, Misinformation, Disinformation (or, “These aren’t the droids you’re looking for.”) Part 1

December 29, 2012 18:07 December 29, 2012 18:07 December 29, 2012 18:07
 

Whose job is it to make this stuff easy to understand?

“YOU CAN’T ALWAYS FIND WHAT YOU’RE LOOKING FOR…..”
[Skip to Part 2] At Safecast we assumed from the start that our data should be accurate, easy to understand, informative, well-visualized, and easily accessible. In many respects this simply reflects “best practices” in information design, as well as a vision of social responsibility in which openness and transparency are paramount virtues. So when we make decisions about how to present our data, we adhere to principles of intuitiveness, depth, context, and dare we say it, beauty in design. We want to make it as easy as possible (AEAP) for people to find what they’re looking for, and to find out what it means. That’s why we’re continually miffed when official sources of information seem to be operating under an entirely different set of assumptions.

To be honest, the seriousness of government missteps and opacity during the early weeks of the disaster led us to accommodate ourselves to vastly lowered expectations in terms of the quality and accessibility of information we’d probably see from official sources. Even though it’s their job, and they are legally required to provide many kinds of information, many of us prepared ourselves for endless tooth-pulling and fact-checking about radiation information. So first, I’d like to give a sort of brief status update:
1) The government has made a lot of information available, more than we expected (because we expected nothing).
2) It still needs to be scrutinized, fact-checked, and independently confirmed.
3) There are still some areas where a lot of us have been pulling teeth for months and still haven’t been able to get the information we’re looking for.

So let’s just agree to live with #2 and #3 for the moment. It means constant effort on our part, but enough of us are constitutionally well-equipped for this kind of research-based tug-of-war that it’s not really that onerous at this point. We get good at it, we build trust, and people who were once opponents sometimes become allies, because frankly, they need our help.

But #1 is where we find ourselves really scratching our heads. There is all sorts of official information available, and a lot of it is proving reliable, but it’s rarely as easily accessible or informative as it should be. In fact, locating and using the data is usually as difficult as possible (ADAP) considering how easy it is now to find good information and web designers, and how inexpensive it has become. It should be easy to do a good job, if the people in charge really care about doing a good job. Continue reading »

Information, Misinformation, Disinformation (or, “These aren’t the droids you’re looking for.”) Part 2

December 29, 2012 18:06 December 29, 2012 18:06 December 29, 2012 18:06
 

A MEXT radiation monitoring post, aka “droid,” of a common type manufactured by NEC . This one is at the former Akasawa Elementary School in Aizu-Misato.

GOVERNMENT MONITORING POSTS

[Part 1 here] In recent months there has been a fair amount of controversy concerning the accuracy of the radiation monitoring posts the government has installed all over Fukushima prefecture, and in some neighboring prefectures as well. We wrote about it back in July, 2012:

TEPCO cheating on radiation levels by using “improved” monitoring posts

There are almost 700 of these monitoring posts (675 at latest count), which we refer to as “droids” because of how they look (see photo above). They are all powered by solar panels and use storage batteries.
[Update: 2700 monitoring posts have been installed as of Feb. 2013]
Through the Ministry of Education, Culture, Sports, Science, and Technology (MEXT), the government spent a lot of money (we haven’t been able to find out precisely how much) to have them installed, and spent more money to have a web site made that displays the readings: MEXT realtime environmental radiation page

From this reasonably attractive-looking page, users are supposed to click on a prefecture, then on a region of the prefecture, and then choose from any one of a dozen or more municipalities. Then a scrolling list appears on the right hand side, and users can select a particular monitoring post to review (In the case of Koriyama City in Fukushima, there are 393 monitoring posts in the list). A zoomable, scrollable Google Fusion map appears, and the individual posts are marked by colored dots. Clicking a dot gives the current reading at that location, updated very 10 minutes it seems, and it is possible to download data for the entire month. So, thank you for doing that much, at least, MEXT.

This system sucks in many ways. While working with it in order to compare the MEXT readings with our own, we’ve found that it’s impossible to get an overview of more than a small part of Fukushima at any one time, that hunting down particular locations is incredibly time consuming and frustrating, that the cumulative time data does not go back far enough, and that the downloadable data comes with many restrictions and is difficult to pull down efficiently. Yes, MEXT made this system ADAP — As Difficult As Possible. Continue reading »

Building bGeigies in Aizu

December 19, 2012 04:51 December 19, 2012 04:51 December 19, 2012 04:51
 

Hikone 2012-12-19

From One Spike to 45 Blinking LED’s.

From one Spike on a Software Scope in a Brazil Bar in Tokyo to 45 Blinking LEDs, the Sound of Fake Digital Crickets in a Science Room in Aizu. (A short summery of part of the flow of the radiation recorded from Cesium in Japan to SAFECAST webpage).

Introduction:

It all started with a short Skype call after having tried the satellite phone. Pieter Franken and others from the “block hoofden” group (a Dutch embassy initiative for organizing Dutch citizen abroad) trying to connect with each other and collecting information how bad the damage of the earthquake was. The next day EenVandaag (Dutch TV channel) called us (Yuka Hayashi and me) to ask if we were willing to go with a reporter and cameraman to Tohoku.

After some doubts we accepted the project. On 2011-03-12 we went to Sendai to visit the family of Pieter in Ishinomaki to make a story for EenVandaag. On the way we were constantly updated with information from Pieter. Sometimes, nearly hourly, he reported to us about the situation of the Daiichi nuclear plant. It became clear that we could not take the road on the east side of Japan and we decided to take the west side, though Nagano-ken.

After 4 days in Tohoku the Dutch TV crew was called back and they offered us the flight with them to Holland. We decided to go with them and see how the situation would develop. In Holland we were often in contact with Pieter to take about ideas how to get a simple measurement for radiation going. Pieter was working on his Iphone bGeigie and at that time I was researching the possibilities to have the same software running on an Android phone. Continue reading »

Safecast Geiger Counter Limited Edition!

June 4, 2012 09:07 June 4, 2012 09:07 June 4, 2012 09:07
 

Earlier this year we announced a new geiger counter, designed by bunnie that we were hoping would be in production soon. We’re excited to announce two things – Firstly International Medcom is full steam ahead on a full production run of these devices that will be available later this year, and secondly we’re releasing a LIMITED EDITION, CLEAR CASE, NUMBERED VERSION exclusively through Kickstarter right now. Medcom and Kickstarter are teaming up to help us with this and the only way to ever get this edition will be to order through this campaign right now (or for the next few days while it’s live). You can read more about it and order here.

NORWAY STILL RADIOACTIVE 26 YEARS AFTER CHERNOBYL

May 29, 2012 16:00 May 29, 2012 16:00 May 29, 2012 16:00
 

2012 CESIUM MAP FOR JOTUNHEIMEN, NORWAY

26 years have passed since the Chernobyl Nuclear Disaster. Many countries in Europe were affected of the radioactive fallout, including Norway which is roughly 2500 kilometers away from Chernobyl.

On May 18, 2012 The Norwegian Radiation Protection Authority (NRPA) reported about a new helicopter survey (covering 3000 square kilometer) of the mountainous area in central Norway called Jotunheimen (home of the giants) which contains the highest mountain in North Europe (Galdhopiggen 2469m / 8100feet) and a large high-mountain plateau called Valdresflye which is the feeding area for about 7500 reindeer. Continue reading »

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