In a BLIP, pervasive IP has arrived.

by Martin Turon, Director of Wireless Software, Crossbow Technology, Inc.

IPv6 was invented in 1998, over ten years ago, yet less than 1% of devices use it.

Why is IPv6 important?

The first answer is "lots of addresses".

Think of your PC and the RAM memory inside. Until recently, 32-bit processors were pervasive, and you couldn't put more than 4GB (4 billion bytes) of memory in them because of the limits in 32-bit address spaces. Now most new computers are 64-bit, and they can address 18 quintillion bytes. The Internet will eventually be forced to "upgrade" its address space as well. Currently over 99% of devices use IPv4 which uses 32-bit IP addresses that are most commonly displayed as 4 bytes in decimal: 192.168.1.100. If you want to host a web server to the world, you typically claim a static IP and one of the 4 billion possibilities is yours forever. But the population of the world is 6.7 billion, so there aren't enough to go around! And what if everyone wants multiple devices that can be uniquely addressed to serve some critical information like a cluster of wireless sensor nodes?

IPv6 is clearly the answer. It provides a 128-bit address space allowing for over 240 undecillion uniquely addressable devices. To put that in perspective, the soon-to-be 6.8 billion people in the world will each be able to have over 300 million subnets with over 18 quintillion devices in each one. That is a total of over 50 octillion uniquely addressable devices per person!  Note: The unallocated address pools in IPv4 are anticipated to be exhausted in 2012.

Which leads to the second answer: "government mandates".

In May 2009, the Federal CIO Council of the US government issued an official roadmap for IPv6 adoption. The report provides a detailed overview of the technology, it's benefits, tips on the various services and how to transition. It also tasks other government agencies with developing concrete plans for how they will deploy IPv6 and requires quarterly review of their progress.

"We can't keep operating in an IPv4 world when we're talking about sensor networks, wireless communications and mobile networks. We need more IP addresses - globally unique IP addresses - and that's what IPv6 provides. We need a target network architecture that's scalable, secure and stable." - Pete Tseronis, Federal IPv6 Working Group Chair and Deputy Associate CIO of the Department of Energy

Since the release of this document, a flurry of articles regarding IPv6 adoption has been written up in the press.

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How can big IPv6 addresses fit on tiny motes?

Almost in anticipation of the recent uptick in IPv6 adoption, back in March some researchers at UC Berkeley released an Open Source implementation of IPv6 running on TinyOS 2.x called BLIP (Berkeley Low-power Internet Protocol). The BLIP stack runs on mote-class hardware, specifically the TelosB and MicaZ. How did they manage to fit a protocol that uses 128-bit addresses onto a platform with only 4KB of RAM? Well, beyond the fact that Stephen Dawson-Haggerty and other contributors are really really smart, the IETF has had a number of efforts to define ways for IPv6 to run on lossy, low bandwidth links for a while. The IETF timeline follows:

RFC 1883,2460 - IPv6 Specification
RFC 1885,4443 - ICMPv6 Internet control message protocol
RFC 3142 - IPv6-to-IPv4 translation
RFC 3315,4580,4649,4704 - DHCPv6 Dynamic, automatic address assignment
RFC 4861 - Neighbor Discovery
RFC 4862 - Stateless Addr Autoconf
RFC 4944 - IPv6 over IEEE 802.15.4 (6LowPAN) 

Drafts: HYDRO routing (part of ROLL [routing over low-power, lossy links] effort)

Papers: IP is dead, long live IP,  Extended Internet Architecture PhD Thesis by Jonathan Hui

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Why is it cool?

IPv6 running on motes is cool because it really leverages what IPv6 was designed for -- ubiquitous computing.  Imagine a day when all of your appliances and consumer electronics will be able to talk to each other and provide you real time data on their energy usage, health, etc.  The ZigBee alliance has recently signed up to define a specification for an IPv6 stack in addition to an RF4CE stack for remote controls and consumer electronics.  Similar to how WiFi is integrated into all sorts of products today and just works, ZigBee may make it so cheap, tiny devices of the future can provide direct IPv6 connectivity over low-power, low-bandwidth radios.

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What is the status of BLIP?  When will it be released?

BLIP is a work in progress.  It is currently fully supported on the TelosB platform and works on MICAz when compiled in a memory-constrained mode.  It is being folded into the TinyOS 2.x core with a slated release date of late August 2009.  The version in contrib/berkeley/blip is the correct one to use, however, as that one will actually build without manually adding radio stack modifications that are still being negotiated.  IRIS support is in the works as well with the initial port being done by European researchers Miklos Maroti and Lars Schor.  An improved release candidate of BLIP is slated to be pushed into contrib as early as next week.

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Where can the BLIP source code be found?  How do you use it?

1) Download Xubuntos 2.1 VMware image (Howto)
2) Start the VM, login as:
  username: xubuntos
  password: tinyos
3) Start a Terminal
4) Prepare your VM to run BLIP as follows:

- Install IPv6 tools:

    sudo apt-get install netcat6

- Update tinyos-2.x trees from CVS:

    cd /opt
    # hit return for anonymous password
    cvs -d:pserver:anonymous@tinyos.cvs.sourceforge.net:/cvsroot/tinyos login
    cvs -z3 -d:pserver:anonymous@tinyos.cvs.sourceforge.net:/cvsroot/tinyos co -P tinyos-2.x
    cvs -z3 -d:pserver:anonymous@tinyos.cvs.sourceforge.net:/cvsroot/tinyos co -P tinyos-2.x-contrib/berkeley

- Add a simple environment setup script

cd /opt/tinyos-2.x-contrib/berkeley/blip
cat <<-EOF > setenv
export TOSROOT=/opt/tinyos-2.x
export TOSDIR=/opt/tinyos-2.x/tos
export LOWPAN_ROOT=$PWD
export TOSMAKE_PATH="$LOWPAN_ROOT/support/make"
EOF

- Build the driver

    cd /opt/tinyos-2.x/support/sdk/c/sf
    ./bootstrap
    ./configure
    make
    cd /opt/tinyos-2.x-contrib/berkeley/blip/support/sdk/c/blip
    make

- Patch motelist to handle mib520 for micaz discovery

cd ~
cat <<-EOF > motelist-linux.mib520.patch
--- motelist-linux	2006-12-12 10:23:01.000000000 -0800
+++ /usr/bin/motelist	2009-05-19 11:28:26.000000000 -0700
@@ -61,7 +61,10 @@ sub scan_sysfs {
 
 # Scan /sys/bus/usb/drivers/usb for FTDI devices
 my @ftdidevs =
- grep { (\$_->{UsbVendor}||"") eq "0403" && (\$_->{UsbProduct}||"") eq "6001" }
+ grep { (\$_->{UsbVendor}||"") eq "0403" && 
+ (((\$_->{UsbProduct}||"") eq "6001") || 
+ ((\$_->{UsbProduct}||"") eq "6010")) 
+ }
 map { {
 SysPath => \$_,
 UsbVendor => snarf("\$_/idVendor",1),
EOF
cd /usr/bin
sudo patch -p0 < motelist-linux.mib520.patch

- Download Blip.micaz.patch

 - Patch the blip contrib sources to add automatic micaz support
and fix some build issues.

    cd /opt/tinyos-2.x-contrib/berkeley/blip
    patch -p0 < ~/blip.micaz.patch

5) Use your prepared VM to build and deploy BLIP:

- Enable the BLIP build environment:

    cd /opt/tinyos-2.x-contrib/berkeley/blip
    source setenv

- Build the UDPEcho app and base station for telosb and micaz:

    cd /opt/tinyos-2.x-contrib/berkeley/blip/apps/UDPEcho
    make telosb blip
    make micaz blip

    cd /opt/tinyos-2.x-contrib/berkeley/blip/apps/IPBaseStation
    make blip telosb
    make blip micaz

- Connect a TelosB via USB, and flash it with the base station code
(Install FTDI drivers if needed)
(Accept TelosB device when dialog appears)
(Right click USB device in lower right of VM and select connect)

    motelist # find ttyUSB port to use
    cd /opt/tinyos-2.x-contrib/berkeley/blip/apps/IPBaseStation
    make blip telosb install,64 bsl,/dev/ttyUSB0

- Connect a MicaZ via USB, and flash it with the remote node code
  (Install FTDI drivers if needed)
  (Accept MIB520 device when dialog appears)
  (Right click USB device in lower right of VM and select connect)

 	 
    motelist # find ttyUSB port to use
    cd /opt/tinyos-2.x-contrib/berkeley/blip/apps/UDPEcho
    make blip micaz install,1 mib520,/dev/ttyUSB0

6) Fire up Linux network driver to communicate with BLIP network:

- Start the ip-driver

    cd /opt/tinyos-2.x-contrib/berkeley/blip/support/sdk/c/blip
    sudo ./ip-driver /dev/ttyUSB0 telosb
    # password: tinyos	 
    # blip console commands:
    # blip:xubuntos-tinyos> help
    # blip:xubuntos-tinyos> log WARN
    # blip:xubuntos-tinyos> routes	

7) Use standard IPv6 tools to access the remote BLIP nodes:

    # Ping - base station and remote node
    ping6 2001:470:1f04:56d::64
    ping6 2001:470:1f04:56d::1

    # Access shell on remote node
    nc6 2001:470:1f04:56d::1

Note that BLIP ships with support for pinging a node with standard the ping6 tool, shelling into a node with netcat (the shell is a custom one, not ssh, type help to see available commands), and over-the-air reprogramming of nodes with a deluge-like interface.  BLIP is an exciting software development for the TinyOS community and users of TelosB, MICAz, and soon IRIS platforms.  We encourage you to try it and track its rapid development.

Martin Turon is Crossbow's Director of Wireless Software. Not only an expert in the field of wireless sensor networks, Martin has been instrumental in simplifying the WSN user experience with advancements in interface and server tools using his background in video game design, mobile phone software and operating systems. He is the current Chair of the ZigBee WSN group which is working to establish the standard for low-power routing while leading the Wireless software development team at Crossbow for future product enhancement. Martin obtained degrees from University of California, Berkeley in Electrical Engineering and Computer Science. He has also studied Artificial Intelligence at University of California, Los Angeles and received a certificate in Math for Financial Engineering from Haas Business School. Martin is an avid lover of indie rock and performs with various ad-hoc musical projects.

Landslide Detection for Mountainous Regions

The Times of India reported today on a wireless sensor solution developed by students of Amrita Vishwa Vidyapeetham University for landslide detection. This development effort used Crossbow's MICAz Mote platform and was done in collaboration with the European commission and Indian Space Research Organisation (ISRO). This pilot deployment of India's first landslide detection system with wireless sensor networks was put in place at Munnar, Idukki, Kerala, India. This implementation brought together scientists from diverse fields such as geology and geophysics, mechanical,computer, electrical, electronics, and communication engineering to save human lives, preserve the environment, and mitigate property damage.

The devastation and loss of life caused by landslides affects hundreds of people every year around the world. Amrita University's rainfall induced landslide detection system uses a heterogeneous network that included wireless sensor networks in combination with Wi-Fi and satellite technology. The pilot site chosen for this study is highly prone to landslides due to systemic monsoon induced rainfalls in the region.

"Landslides occur frequently in mountainous terrains, especially during monsoons but detecting them in advance is not an easy task,'' says Dr P Venkat Rangan, vice chancellor, Amrita university. An expert in wireless communication, Rangan led a team of students in developing the model that has become operational in Munnar town in the Idukki district of Kerala.

This breakthrough technological system was developed as part of the research project WINSOC (Wireless Sensor Network with Self-Organisation Capabilities for Critical and Emergency Applications). Wireless panels with sensor nodes to read different soil parameters such as moisture, vibration and movement were embedded 15 metres beneath the earth at different points, says Maneesha Ramesh, a faculty member, who was part of the project.

The actual deployment site in the Idukki district built on the existing setup at Munnar as it provided the infrastructure needed for retrieving geological and hydrological data from the field as it was necessary for the data to be transmitted a long distance for further analysis. The data received from the geophysical sensors were transmitted through the wireless sensor network which used a two layer hierarchical topology.

The sensors were attached to a wireless transmission device, in this case Crossbow's MICAz Mote platform, which would then convert the analog value into a digital value and send the inputs to the base stations, which were connected to Amrita mutt's Kollam campus. "Experts will be monitoring the inputs from the base stations in real time and any unusual behaviour or extreme value will trigger an alarm,'' says Dr Rangan.

Multiple sets of geophysical sensors are located in a distributed manner inside a column, referred to as the 'sensor column'. The sensor columns are approximately 5 -6 meters long and are buried deep inside the earth and the data from them are retrieved using lower layer wireless sensor nodes attached to the sensor columns.

The lower layer wireless sensor nodes were wirelessly connected to a hierarchy of upper level wireless nodes that would forward the data on to a Gateway. The data was then sent via a directional Wi-Fi link to a Field Data Management Center (FMC). The data was then forwarded over a satellite link to the Data Management Center (DMC) which has sophisticated landslide data processing and modeling capability, located at Amrita University, Amritapuri campus which is situated approximately 252 kilometers away from the deployment field.

The fully tested model has become operational in Munnar. The system can be deployed in any part of the country prone to landslides and snow avalanches. The application could also be put to industrial use for the study of gas leakages or in conservation of forests by early identification of forest fires during summer.

As part of this project, representatives from various European partners like University of Rome, Selex Communications, Intracom Telecom, Czech Centre for Science and Technology arrived at the Amrita University to learn about the first-ever wireless sensor network system for landslide detection. The Amrita wireless sensor network system for landslide detection has been developed as part of WINSOC which is co-funded by INFSO DG of European Commission.

Crossbow AHRS featured on AeroTV

Advancements in AHRS technology were featured today on AeroTV. An interview with Mike Smith, Crossbow's OEM Account Manager of Inertial Systems, provided viewers with some insight and explanation regarding the solid-state technology of the popular AHRS (Attitude and Heading Reference Systems) that are dominating the General Aviation market.

Tue, 09 June 2009.

Such Innovative Technologies Have Become Commonplace In GA

You know that they're there -- but you rarely see them -- the tiny little boxes that provide the physical guidance for today's ingenious generation of glass panel cockpits. Solid-state by design and bereft of the hundreds of moving parts once associated with gyros and their support systems, the modern AHRS is a dependable, and superior replacement for the vacuum pumps and gyros of old.

Known by a variety of similar names, the modern AHRS is an all-electronic Attitude and Heading Reference System that combines the functions of a Vertical Gyro and a Directional Gyro to provide measurement of Roll, Pitch, and Heading (Azimuth) angles. Aero-TV took a little time at the recent 2009 AEA Convention to get an AHRS education from one of the leaders in the field... Crossbow Technologies.

Founded in 1995, Crossbow pioneered the use of Micro-Electro-Mechanical System (MEMS) Inertial System technology in a wide variety of airborne, land and marine applications. Crossbow first introduced FAA-certified MEMS-based Attitude and Heading Reference Systems (AHRS) to General Aviation on the FAA Capstone program, and the company continues to be at the forefront of AHRS and Inertial Systems development.

With corporate headquarters in San Jose, CA, and Asian offices in Tokyo and Osaka, Japan, Crossbow has distributors in 24 countries worldwide. Crossbow is ISO 9001/2000 certified, holds several FAA TSO approvals, and operates an FAA MIDO approved facility.

Aero-TV: 21st Century Attitudes - AHRS Technology Explained

Special Presentation at Sensors Expo

On June 8th at 9AM, attendees at the Sensors Expo in Chicago, IL, will have the opportunity to hear from Crossbow's Dr. Ralph Kling. Dr. Kling will be be giving a talk entitled Rich Data Types for Sensor Networks. If you are in the Chicago area or will be attending the 2009 Sensors Expo, be sure to hear Dr. Kling's presentation on the current state of sensor networking technology and how advancements in local data processing, sensor data fusion and the conversion of data to meaningful information is expanding the horizon for how and where WSNs may be deployed.

Dr. Ralph Kling is currently the Chief Architect of the Wireless Business Unit at Crossbow Technology. Dr. Kling is leading the Wireless engineering team at Crossbow and is responsible for new product strategies, technical directions and Standards activities.

For more information on the Sensors Expo, click here.
For more information on Crossbow's wireless sensor network products, click here.

Details regarding Dr. Kling's presentation will be posted in the next week.

eKo network at NRS reserves pioneer new ways to observe Earth!

Crossbow's revolutionary eKo system was featured in the Spring/Summer Edition of Transect. The main article focuses on the implementation of sensor networks for observation. The eKo system is being used to monitor the microclimates of the various wetlands at the Blue Oak Ranch Reserve. The goal of the deployment is to collect detailed and accurate measurements about the environment to track changes, but also determine how these changes affect the plant life and various species within that ecosystem.

Reserve Director Mike Hamilton was looking to draw on the Blue Oak Ranch Reserves proximity to the Silicon Valley to collaborate on this product development and stated how products from Crossbow and other technology companies have been deployed, "...to show different applications for the tools and relevant
applications... so we’re teaming them with faculty and students from UC Merced to monitor wetlands that support salamander populations by deploying sensor networks to measure the changes in rainfall, soil moisture, water depth, and some of the chemical parameters of the water, such as salinity, that vary
across the reserve’s ponds, depending on soil type and water source. They all have different populations of amphibians, and they’re going to be different from pond to pond, so if we can set up these test beds in a few different wetlands, we can do comparisons across the reserve. We also want to test the reliability of the systems because, in the future, the reserves will want to pick those that prove their worth.”

Using various soil moisture sensors and ambient temperature/humidity sensors with the eKo node, researchers are able to gather valuable data quickly and easily. With its ecofriendly solar-panel and weatherproof enclosure, the eKo system takes technology into the wild! Using the advancements in networking technology, engineers and scientists working at the University of California, NRS reserves are playing a key role in the global discovery occurring through monitoring. The "Alpha Node" tower at Blue Oak Ranch provides information about data above ground and underground. As Hamilton states, "It’s a solar-powered weather station, but it’s also a wireless relay point that links the Lick Observatory [owned and operated by UC and located on nearby Mt. Hamilton*] to a directional Wi-Fi radio that points down to the barn, providing us with Internet access. And this omni-directional antenna plugs into the router on the tower to create a large Wi-Fi cloud on the top of the hill that’s strong enough to get a signal down to the pond and the stream at the foot of the hill, so researchers will be able to monitor these locations using portable wireless environmental sensing systems.”

Much of this work is based on the CENS research done at the James Reserve. This research has had a major influence on ecological observatory networks throughout the world. “It’s such a huge field of integration of interdisciplinary science between engineers and computer scientists and environmental scientists,” notes Hamilton. “It seems that everyone is doing sensor networks today...There’s a lot of growth right now in using sensor systems for precision agriculture, ranging from viticulture to golf course irrigations. Those seem to be the big areas where embedded-sensing and mesh networks are playing out. Our field, ecological monitoring of microclimates across a diverse landscape, is a niche market." Hamilton discusses how these deployments reflect the change in sensor networks from engineering projects to commercial off-the-shelf solutions such as the eKo platform.  

To read the full Transect article visit the NRS site here. For more information on the eKo system contact Crossbow or click here.

Ways to Save Water

Crossbow's eKo system was prominently featured in the Press Democrat this week. The article highlights the importance of irrigation management and water conservation as well as the use of stress irrigation to grow higher quality grapes. Several systems were installed in Napa's Alexander Valley to highlight the benefits of using water monitoring systems. Crossbow's eKo system was one of these solutions.

To view the entire article, click here.

Six different irrigation systems are being installed side by side in an Alexander Valley vineyard in a demonstration of water conservation.

“We are looking at deep irrigation versus shallow, night versus day, one emitter per vine versus two,” said Mark Greenspan of Advanced Viticulture of Santa Rosa, a grower’s consulting firm.

The concept is to reduce water use by 10 to 20 percent, a conservation goal that is increasingly important this year as the North Coast suffers through another drier-than-normal year.

“I think it’s very valuable, potentially,” said Nick Frey, president of the Sonoma County Wine Grape Commission. “People change farming practices when they are convinced they can do it and it is not risky. If you can show that they can reduce water and produce a good grape crop, it is very valuable.”

The project at Hoot Owl Creek Vineyard is being financed by the Sonoma County Water Agency. The agency this year is under a proposed state order to reduce summertime flows in the Russian River and cut the amount of water it takes from the river by 25 percent to conserve water in Lake Mendocino for the fall salmon run. The state Water Resources Control Board is also proposing that conservation goals of 50 percent be set for Mendocino County and 25 percent for Sonoma County, and irrigating commercial turf be banned.

Grape growers farm about 60,000 acres in Mendocino County and in Alexander and Russian River valleys in Sonoma County. They use a third of the water in the Russian River watershed, according to water agency officials.

Greenspan believes that growers routinely over-irrigate vineyards, irrigating once a week for eight hours, using about eight gallons per vine. But that water goes too deep, soaking the soil past the root system. Roots go down as much as three feet in the soils that are common in the Russian River watershed, Greenspan said.

“You will lose a lot of water below the root system,” Greenspan said. “We want to stress the vines to produce good grapes, but not over-stress. We want less water and more often.”

Greenspan said his irrigation method has been used in a Beaulieu Vineyard ranch in Napa County for the past year, and saves 10 to 20 percent in water use. At Hoot Owl Creek Vineyard, the different irrigating systems are being installed on a half-acre plot of eight-year-old cabernet sauvignon vines. Moisture and temperature sensors will be used to monitor the soil and grapes in real time. The measurements will be sent by solar-powered transmitters from the vineyard to an Internet site, where they will be available for anyone to see.

By BOB NORBERG

To truly understand the return on investment (ROI) growers can expect to receive from using a water system management tool like the eKo platform, growers can use the eKo ROI calculator to determine how much they would need to spend to outfit their vineyard with the eKo solution and the time period during which their payback would be realized. For more information on the eKo system, visit Crossbow's site. To input your data and determine your return on investment click on the calculator below:

 

Derby Days

This past Saturday, May 2nd, the 135th running of the Kentucky Derby took place at Churchill Downs in Louisville, Kentucky. In an improbable ending, Jockey Calvin Borel rode Mine That Bird - a 50-1 longshot - to a huge victory, coming from dead last to win by 6 3/4 lengths. The Kentucky Derby is often billed as "the most exciting two minutes in sports", and Borel and Mine That Bird did their best to live up to that standard. 

The power and force exerted by these animals in those 2 minutes is amazing! A robotic hoof mechanism was shown at the derby. The image below shows the device clad with an aluminum shoe. The mechanism simulates the force, angle and impact of a racehorse hoof, and makes measurements to help detect trouble spots on tracks. Professor Mick Peterson demonstrated the machine while testing the racing surface at Churchill Downs on Saturday, April 25th, the week before the race.

The device used one of Crossbow's accelerometers to collect the data necessary to make these measurements. These accelerometers provide superior performance in small packages. With expertise in MEMS (Micro-Electro-Mechanical Systems) and DSP (Digital Signal Processing) technology, Crossbow accelerometers deliver reliable, cost-effective solutions across a wide range of applications. Several different accelerometers are offered, each optimized to meet customer needs in targeted fields.

Prof. Mick Peterson's research at University of Maine on Animal Biomechanics takes engineering technology and applies it to real life situations. Creating the robotic hoof allows owners the comfort of knowing that the track is safe for the horses to race on, offers them a playing field to encourage optimal performance and provides a fair and consistent racing surface to all riders. The device allows owners to understand the exercise impact of various tracks on the bone density of the horses, and the modeling done by the machine suggests that the device measures soil properties more than 1 foot beneath the track's surface. For more information on this research visit Professor Peterson's site here and for details on Crossbow's accelerometers, click here.

Congratulations to Kentucky Derby Winner Mine Than Bird and Borel for an amazing win!

Who said it ain't easy being green?

It seems that everywhere you turn you are being encouraged to go green. I hung out with a friend the other day and she was wearing a shirt that said 'Green is the new black.' The idea of being environmentally friendly has taken our world by storm. The Discovery channel brought us Planet Earth to give us a closer look at the different environments on our planet and how little by little we are altering and damaging it. Musicians from around the world held a 24 hour concert called Live Earth to capture an audience of millions and educate them on how to live a more eco-friendly lifestyle. There are more and more hybrid cars on the road and most products you buy sport the small leaf logo advertising that they are environmentally conscious. President Obama has assembled a dream team of environmental experts and specialists to focus on clean energy and climate change issues.

If you look around, you realize that our society is truly looking to conserve resources and use the technology and knowledge we have to ensure we are saving the Earth. Crossbow's eKo platform is a truly breakthrough product that revolutionizes the way we use the resources in our environment. Imagine saving water but increasing your yield and the quality of your harvest? The eKo platform is a device that not only stems from the knowledge and genius of taking any environment and making it smart, but also from knowledge of our world and how it works. The ease with which the nodes can be deployed favors leaving an environment intact without having to run wires and cables disrupting the natural flow all around. The system has been deployed in various applications ranging from the standard vineyard/ orchard/ crop monitoring, to greenhouse gas monitoring in nurseries, to measuring the snow pack/run-off to determine what type of drought conditions regions can anticipate, to structural integrity, to water level measurements, to contamination of watersheds for environmental protection and much, much more.

As we continue to see this product deployed around the world, the consistent theme is that the platform is so easy to use and leaves users with a higher understanding of the their environment. By integrating the various sensors offered with the eKo platform, users can determine when disease conditions could occur. Instead of having to spray chemicals over their entire crop, growers can pinpoint which block, row or plant is in danger. By knowing and monitoring the environmental parameters that cause these conditions, not only can they be avoided but the use of unnatural elements and chemicals can be prevented preserving the natural state of the area. The ability to gather this data, analyze it and make decisions is all available in the eKoView web application that comes free with the eKo system. Bringing this type of data collection to the internet has transformed the notion of connecting with the world around you. It is truly an eKo-centric solution to the environmental issues we face today. It seems fitting that this type of technology would come from a company based in the San Francisco Bay Area, city of St. Francis patron saint of the environment, and the heart of the Silicon Valley known for its high technology advancements.

Today as we recognize Earth Day it is important for people to embrace the new technologies looking to preserve and help conserve our planet's resources. A system like eKo provides users with a solar powered wireless device thus removing the need for battery replacement and disposal. It's sealed enclosure allows it to weather the elements ranging from snow covered mountains to the heat of the California sun. It's ability to interface many types of sensors make it a requisite part of any environmental monitoring deployment. eKo provides a platform that can be used to create smart water grids, detect air pollution, do conservation studies, perform chemical detection, ensure water quality, monitor urban environments, etc. The ability to capture data in these and many more applications wirelessly and easily will help us move towards a future Earth that is cared for and that can be healed with proper conservation of its resources. Thanks to the convergence of technology and environmental awareness in eKo - It is finally easy to be green!

For more information on the eKo system, contact Crossbow Technology at eko.sales@xbow.com or at 1-800-XBOW-TEC.

Testbed Testing

Wireless sensor network testbeds are critical for understanding and meeting the technical challenges of networks deployed in real world scenarios. Hardware and software testbeds have become the preferred basis for experimenting with embedded wireless sensor network applications. They provide a means for developing and evaluating sensor network technology in a controlled and instrumented environment. Experimentation with current hardware and software platforms, allows users to not only demonstrate applicability in real environments but also to validate prototypes. Compared to field deployments, the testbeds yield substantial efficiency in instrumenting potentially long-lived experiments, which is valuable in the debugging, validation, and integration phases of reliable wireless sensor networks. Universities and labs across the world have set up networks of hundreds of nodes using a Mote platform from Crossbow's suite of wireless sensor network devices choosing from simple platforms such as the TelosB to advanced devices like the Imote2.

Researchers at the University of Buffalo, SUNY and Georgia Institute of Technology have written an article focused on the the idea of taking wireless testbeds to the next level by incorporating multimedia and characterizing the challenges of wireless multimedia sensor networks (WMSNs). The availability of low-cost hardware has enabled the development of WMSNs, i.e., networks of resource-constrained wireless devices that can retrieve multimedia content such as video and audio streams, still images, and scalar sensor data from the environment, along with standard wireless sensor networks. Research is being conducted on prototypes of multimedia sensors and their integration into testbeds for experimental evaluation of algorithms and protocols for WMSNs. Open research issues and future research directions, both at the device level and at the testbed level, are discussed and tested constantly.  Network testbeds allow the effectiveness of algorithms and protocols to be evaluated by providing a controlled environment for measuring network performance.

Every testbed utilizes a specific Mote platform that is optimized for that particular testbed's focus. The wireless sensor platform is chosen based on its available capabilities to allow for multimedia integration. A WMSN is a distributed wireless system that interacts with the physical environment by observing it through multiple media. Furthermore, it can perform online processing of the retrieved information and react to it by combining technologies from diverse disciplines such as wireless communications and networking, signal processing, computer vision, control, and robotics. Applications in the real world that would benefit from WMSNs were categorized into the categories of surveillance, traffic monitoring and enforcement, personal and health care, gaming, and several elements of environmental and industrial monitoring by researchers at SUNY, Buffalo and Georgia Tech. Testbeds allow the observation of the performance of the WMSN in a controlled environment. Hence, the effect of different types of inputs, physical operating conditions, and subjects for sensing can be studied, and the functioning of the devices in the testbed may be changed appropriately for accurate measurement. A few WMSNs developed are outlined below:

A visual sensor testbed was developed as part of the Meerkats project to measure the tradeoff between power efficiency and performance. Results revealed that there was significant energy consumption in keeping the camera active, and writing the image to a Flash memory followed by switching the camera off conserved energy. There was also a finite instantaneous increase in the energy consumption due to state transients. Researchers were also able to determine that the processing-intensive benchmark resulted in the highest current requirement, and transmission was shown to be only about 5% more energy-consuming than reception.

Expandable, vision-, and sensor-equipped wireless robots with MICA sensor motes for networking were designed in the Explorebots testbed architecture. The target localization experiments on the testbed, composed of these mobile robots, used on board multimedia sensors such as custom-designed velocity and distance sensors, motor movement control, an in-built magnetic two-axis compass, and sonic sensors. By processing the sound and light sensors outputs, the robots were guided towards the target source.

The Mobile Emulab network testbed provided a remotely accessible mobile wireless and sensor testbed. Robots carried motes and single-board computers through an indoor field of sensor-equipped motes. A remote user could position the robots, control all the computers and network interfaces, run arbitrary programs, and log data in a database. The path of robots, which was also equipped with Webcams, could be planned, and a vision-based system provided positioning information with an accuracy within 1 cm.

IrisNet (Internet-scale resource-intensive sensor network services) was an example software platform for a heterogeneous WMSN testbed. Video sensors and scalar sensors were spread throughout the environment and collected potentially useful data. IrisNet allowed users to perform Internet-like queries to video and scalar sensors that spread throughout the environment. The architecture of IrisNet was two-tiered: heterogeneous sensors implemented a common shared interface and were called sensing agents (SAs), while the data produced by sensors was stored in a distributed database that was implemented on organizing agents (OAs). Different sensing services were run simultaneously on the architecture. For example, a set of video sensors could provide a parking-space finder service, as well as a surveillance service.

In the design and implementation of SensEye, a multiple-tier network of heterogeneous wireless nodes and cameras, was created to test surveillance applications. Each tier comprised nodes equipped with similar cameras and processing ability, with increasing resolution and performance at each stage. The lowest tier consisted of low end devices, i.e., MICA2 Motes equipped with 900 MHz radios interfaced with scalar sensors, e.g., vibration sensors. The second tier was made up of motes equipped with low-fidelity Cyclops or CMUcam camera sensors. The third tier consisted of Stargate nodes equipped with Webcams that could capture higher fidelity images than tier 2 cameras. Tier 3 nodes also performed gateway functions, as they were endowed with a low-data-rate radio to communicate with motes in tiers 1–2.The aim was to efficiently undertake object detection, recognition and tracking by triggering a higher tie into the active state based on a need basis.

The WMSN-testbed at the Broadband Wireless Networking (BWN) Laboratory at Georgia Tech was based on commercial off-the-shelf advanced devices and had been built to demonstrate the efficiency of algorithms and protocols for multimedia communications through wireless sensor networks. The testbed was integrated with the scalar sensor network testbed, which was composed of a heterogeneous collection of Imote and MICAz motes from Crossbow. The testbed allowed the integration of heterogeneous devices in experimental testbeds and some succesful examples in developing APIs and system software for WMSNs.

These are just a few of the various wireless sensor network testbeds found worldwide. Crossbow's vast portfolio of wireless sensor platforms provides researchers and government/commercial users with the equipment they need to set up a lab for their wireless sensor course or to verify their specifications prior to real world deployment of their wireless sensor network. For information on how to set up your own WSN testbed or for details on Crossbow's wireless sensor network platforms, contact sales@xbow.com.

Professors design AK47-locating 'smart dust' helmets

Last week Vanderbilt University's inhouse Exploration newsletter reported on the gunshot-locator net developed by the university's Institute for Software Integrated Systems (ISIS). Crossbow's Mote platforms were once again highlighted in their use for the shooter location system. Acoustic gunshot detectors have become common in the past few years, and some have been reduced in size to where a single soldier can wear one on his uniform and be cued-in to an enemy's location as soon as he fires. Engineers at ISIS have developed a system that can give soldiers just such an edge by turning their combat helmets into "smart nodes" in a wireless sensor network.

Current systems rely on centralized or stand-alone sensor arrays. This limits their accuracy and restricts them to identifying shooters at line-of-sight locations. By contrast, the ISIS system combines information from a number of nodes to triangulate on shooter positions and improve the accuracy of its location identification process. It also uses a patented technique to filter out the echoes that can throw off other acoustic detection systems, explains Akos Ledeczi, the senior research scientist at ISIS who heads up the development effort.

ISIS developed this novel technology with the support of the Defense Advanced Research Project Agency and the university has patented the system's key elements. "When DARPA gave us the assignment of creating a shooter location system using nodes with very limited capabilities, they didn't think we could solve the technical problems," Ledeczi admits. "At first, I didn't think we could do it either, but we figured out how to make it work!"

Retired U.S. Army Lieutenant Colonel Albert Sciarretta, who assesses new military technologies in urban environments for DARPA, is one of the experts who is impressed by the ISIS system: "It's strong points are that it isn't limited to locating shots fired in direct line-of-sight, it can pick up multiple shooters at the same time, and it can identify the caliber and type of weapon that is being fired."

"Because the microphones on the helmet are so close together, the precision is not very high," Ledeczi says. "However, the nodes are continuously exchanging the times and angles of arrival for these acoustic signals, along with their own locations and orientations. When two or more nodes detect the shot, they can provide the bearing with better than one degree accuracy. The range is typically within a few meters even from as far as 300 meters. The more sensors that pick up the shot, the more accurate the localization." The ISIS system communicates its findings with the personal digital assistants that the soldiers carry. The PDAs are loaded with maps or overhead pictures of the area upon which the shooter locations are displayed.

In each package is a wireless network node, of a type dubbed a "smart-dust mote" for its small size and cheapness. There are also four separated microphones, for picking up the acoustic signatures of flying bullets, and a GPS satnav location system. The GPS isn't accurate enough to act as a basis for properly pinning down opposing gunmen, so the Vanderbilt boffins added a crafty radio interferometry enhancement system of their own - apparently of such cunning that it has attracted as much interest as the rest of the system on its own.

The system works by picking up the distinctive conical shockwave trailing behind a passing supersonic bullet - the same phenomenon which produces a sonic boom behind a plane at Mach 1+. This is then related to the muzzle blast from the weapon which fired it, trailing slightly behind (the two noises are heard by people under fire as "crack-thud", or "crack-bang"). A software algorithm in the unit can work out a range and bearing to the enemy weapon's muzzle. A video of the trials can be seen on the Exploration site:

The ISIS shooter system uses the wireless nodes produced by Crossbow Technology Inc. These smart nodes, or motes, form self-organizing wireless-sensor networks and are the realization of the Pentagon's "smart-dust" concept of radically reducing the size and cost of sensor networks for military applications. Current commercial shooter location systems are extremely expensive, with prices ranging from $10,000 to $50,000 per unit. By contrast, an entire node for the ISIS system weighs only slightly more than the four AA batteries that power it and costs about $1,000 to construct using currently available commercial hardware.

The Exploration article is here, and a detailed paper from Ledeczi's team here.