San Francisco Chronicle Features Crossbow's eKo System

Crossbow's eKo system has triggered an agricultural revolution in the world of precision agriculture and environmental monitoring. This cutting edge system was recently featured in the San Francisco Chronicle and the story can be viewed here.

(08-31) 15:50 PDT -- On a rolling hillside planted with row upon row of Cabernet grapes, viticulturist Jason Cole waxes eloquent about the elusive notion of 'terroir,' a term French farmers use to describe the 'je ne sais quoi' of crops harvested in any given locale.

"Grapes, chocolates, coffee, these are all incredibly good at soaking up their environments and spitting them out in their fruits," said Cole, who oversees the preening and pampering of more than 500 acres of vines planted at the Stagecoach Vineyard in Napa County.

That vineyard is a test bed for a new wireless sensing technology that measures soil wetness, wind speed, temperature and humidity to take the statistical pulse of the vineyard's microclimates to help determine how often and how much to irrigate. The system being tested at Stagecoach was developed by Crossbow Technology, a privately held, 90-person San Jose company that has created inertial guidance sensors for the aviation industry and researched the use of wireless sensor networks for the federal Defense Advanced Research Projects Agency. Other manufacturers of microclimate sensing systems include the Austrian company Adcon Telemetry, as well as Ranch Systems of Novato and Grape Networks of San Ramon.

The sensors that Cole is using at Stagecoach Vineyard represent one manifestation of a broader phenomenon called precision agriculture - the attempt to tailor the cultivation of large stretches of land so that the smallest possible subsection of a farm gets special but automated attention. In the Midwest, with its amber waves of grain, precision agriculture has been synonymous with huge tractors equipped with global positioning systems to keep the rows straight, for instance. But in California, the land of fruits, nuts and other specialty crops, precision agriculture has been expressed in technologies such as Cole's efforts to use wireless sensors to compute 'terroir.'

"The way that growers for many years decided whether it was time to water was they stuck their thumb in the ground," said Robert Robinson, vice president for Crossbow's wireless sensor division.

The basic field kit that Crossbow released earlier this year, priced at $3,359, consists of three sensing nodes that feed data collected in the field through an electronic gateway into what is essentially a Web page that can be viewed from any Internet-connected device. Crossbow says that basic configuration can divine the microclimate of sites as varied as a 4-acre plot of land in hilly and varied terrains such as Napa and 20 acres in the flatter, homogeneous Central Valley. Additional kits can extend the sensing network, wirelessly and indefinitely, over hill and dale.

Moisture sensors
Kneeling alongside a vine at Stagecoach Vineyard, Cole explained how the system, in addition to measuring temperature and humidity with above-ground sensors, sticks a virtual thumb deep into the soil in the form of two moisture sensors, one at a depth of 1 foot and the other at 3 feet.



"The whole point is to monitor what the roots are experiencing," Cole said. "Watering grapes is one of the most important factors to wine quality. You want to stress the vines in order to condense the flavor into smaller berries."

UC Davis Professor Stu Pettygrove, a soil specialist who has tracked precision agriculture in California, said the water-sensitivity of wine grapes, coupled with their high value relative to other agriculture products, make them a good candidate for this high-tech approach. But how many other California crops fit that description? Pistachios were the only other example Pettygrove offered. He said water-stinginess at just the right point helps burst the shells, making pistachios easy to eat.

Tree crops experiment
Professor Michael Delwiche, chairman of biological and cultural engineering at UC Davis, has experimented with wireless sensing systems that precisely apply water - sometimes mixed with chemical fertilizers in a process called fertigation - to tree crops like nectarines. So far, however, the cost benefit is not there in production orchards, he said.

Delwiche said wireless sensing systems and precision watering might find a home in commercial nurseries and flower-growing greenhouses, where the impetus is not purely economic - as measured by greater crop value - so much as it is regulatory. "They are under environmental regulation not to have runoff from the nursery location," Delwiche said. Eventually, manufacturers will try to improve the performance and bring down costs to encourage broader adoption of wireless sensing systems, he said. Meanwhile, the technology remains economical in niche markets - or exceptionally arid locales.

"In Israel, where water is so dear and they have the technological infrastructure, they're doing a lot of work in this area," Delwiche said. But at Stagecoach Vineyard, where cachet is central to the business plan, the cost of wireless sensing technology is hardly a barrier to the pursuit of quality.

"We're trying to grasp the 'terroir', but you'll always be grasping, you'll never have it all," Cole said.

For more information on the eKo system, visit the eKo site here.

An ēKo-nomic solution for Nursery Monitoring

If you took a look at the plants in my yard, or had caught a glimpse of the few potted plants I attempted to care for in college it would be quite obvious that my thumbs are not green. The soil would usually be too wet or too dry and the leaves wilted leading to my plant's eventual demise. Imagine having acres and acres of plants to monitor and care for...is there a way to do this ēKo-nomically?

The FLOW-AID project is working to contribute to the sustainability of irrigated agriculture by developing, testing in relevant conditions, and fine-tuning through feedback, an irrigation management system that can be used at farm level in situations where there is limited water supply and water quality. The FLOW-AID project in collaboration with the University of Pisa has installed an ēKo system at an experimental nursery in Tuscany, Italy to monitor soil moisture at eight different locations in the nursery.

The system is designed to serve as an assistant for communication with higher level water management systems at basin scale for long and short term water use planning and prediction. This project integrates innovative sensor technologies into a decision support system for irrigation management while taking into consideration several factors in a number of third country partners. The ēKo nodes have been deployed in eight locations over the nursery in Tuscany. The ēKo ES1101 soil moisture sensors are monitoring the ornamental shrubs and trees being grown to make sure that all the water is being used efficiently and effectively.

The project results yielded will showcase the development and testing of new and innovative, but simple and affordable, technical concepts for irrigation under deficit conditions used at the farm level in a large variety of set-ups and constraints. It will show the development of a water management support system (DSS) that contains an expert system (off-line/long-term) to assist in farm zoning and crop plan in view of expected water availability (amount and quality) with a link to Basin Management, as well as a crop response module that can be incorporated into the irrigation scheduler that allocates available water(s) among several plots and schedules irrigation for each one with a link to Basin Management.

The FLOW-AID project has set up four test sites in various market conditions with different irrigation structures, crop types, local water supplies and constraints. The hardware/software systems used must adapt the general concept of water management to the local situation by using appropriate parts of it at the global sites in Lebanon, Jordan, Turkey and Italy.

The information being collected at the site in Tuscany, Italy, by the researchers at the University of Pisa for container crops and nursery grown crops is available to users over the internet via ēKo's EG2100 gateway device and the ēKoView interface. This device provides, in a fully integrated package the connection between ēKo Sensor Nodes deployed and the ēKo Gateway. The work done by FLOW-AID will be carried out between 2006 and 2009 as a 6th Framework European project under the call for water in agriculture, new systems and technologies for irrigation and drainage. For more information on the ēKo system, click here.

Now that's a bright idea!

Presenting the new 'Ping-pong' Illumimote, a light sensing module for the Crossbow Mote platform. Wireless sensor networks have permeated the market in many sectors such as environmental monitoring, asset tracking, industrial automation, etc. But, these devices have exciting applications in arts, multimedia and entertainment as well. Limited sensing quality, fidelity and diversity of the sensor modules have limited their expansion into areas like film, video production and lighting control. To support research and development in these areas, high-fidelity light sensing modules in a compact form factor are required.

Enter the Ping-Pong Illumimote! This device achieves performance comparable to a commercial light intensity meter, while conforming to the size and energy constraints imposed by its application in wireless sensor networks. The board was developed to replace the light sensing capabilities on the MTS310 Mote sensor board whose response time and narrower dynamic range in light intensity capture is unsuitable to many certain applications for light measurement such as media production. The Illumimote features significantly improved SNR due to its adoption of high-end photo sensors, amplification and conversion circuits coupled with active noise suppression, application-tuned filter networks, and a noise-attentive manual layout. Unlike the MTS310, the Illumimote can capture RGB color intensity (for color temperature calculation) and incident light angle (which discerns the angle of ray arrival from the strongest source). The prototype was created by the UCLA NESL & the UCLA Hypermedia Studio, a joint effort between the film makers and the engineers, to apply wireless sensor networks to new purposes in art and entertainment.



The order in which an audience views a film’s sequence of events is remarkably different from the order in which they are produced. Shots are filmed in the order that minimizes cost and makes best use of actors, crew, and locations. Footage captured at these different times must appear the same when shown consecutively, or differences must be controllable if they are required for creative purposes. It is important to monitor and replicate the quality of light (illuminance and color) in each shot, so that footage captured at different times or in different locations doesn’t show unexpected differences, which may not be perceived by the human eye but affect the film stock. The Lord of the Rings trilogy, for example, was filmed over a year and a half of production and required that footage be captured for use in three different movies with vastly differing release dates and schedules. Researchers at UCLA have focused on lighting instrumentation as the first component of their Advanced Technology for Cinematography (ATC) because of its vital role in the creative process of filmmaking. ATC is a joint project of UCLA’s Henry Samueli School of Engineering and Applied Science and the School of Theater, Film and Television. The Illumimote is part of their larger vision to increase flexibility and creative control in media production using sensor networks and other emerging technologies. Deploying networks of tiny sensors adds a data acquisition layer to the film production environment that supports on-set decision making, such as the lighting adjustment described above, as well as post-production and asset management.

Initial work prompted the development of the Illumimote and other high-quality sensor platforms that can be deployed atop Mica Motes, the defacto standard for WSN nodes. The Illumimote is designed to have equal or better performance to the class of commercial light intensity and color temperature meters used in the entertainment, film and video production industries. It supports three different light sensing modalities: incident light intensity, color intensities and incident light angle (the angle of ray arrival from the strongest source), and two situational sensing modalities: attitude and temperature. The device demonstrated significantly faster response time (> 6x) and a much wider dynamic range (> 10x) in light intensity measurement as compared with the standard MTS310 Mote sensor boards. The light-angle estimation results were well correlated with an average error of just 2.63°. The assembled Illumimote with a lumisphere appears in the picture above. The role of the lumisphere is to protect the sensors and to integrate incident light from all directions.

The overall system architecture diagram of the Illumimote appears below. There are eight light sensor channels allocated based on the number of detector circuits required to capture the illumination attribute. For example, the color temperature unit requires three channels—one for each of red, green, and blue luminosity. Signals from the eight light acquisition units and four situational units are multiplexed via the channel selection unit and presented to the ADC for conversion into a 10-bit digital signal. This resultant data is conveyed to the networked and embedded nodes (in this case, MICAz motes) via either the I2C data bus or a direct 16550Acompatible UART link that uses line-level (rail-to-rail) output. The operation of the Illumimote’s units may be controlled directly from the Mote via the I2C bus or locally by an onboard Atmel Atmega48 microprocessor. Employing the local processor relieves the network interface (mote) of any realtime constraints associated with frame-rate-accurate sampling. The local processor also exposes interrupt facilities both to and from the host-processor onboard the mote. When operating in this mode, the continuous I2C bus may be severed and reattached dynamically (hardware is bus-state aware) to create two isolated buses—one local to the Illumimote, and one local to the Mote—as needed. In addition to calibration functions, the embedded temperature sensor can wake a sleeping mote in the event of a dangerous thermal condition (risk of meltdown). On the bottom, Illumimote features a connector that is compatible with standard Mote-type sensor nodes (IRIS, MICA2, MICAz, Cricket etc).



Three embedded software components were developed for the experimental wireless sensing system. First, sensor and sensitivity control software was programmed and downloaded to the Illumimote board. The board was then attached to a MicaZ node that has a 7.37MHz 8-bit microprocessor and a 250kbps ZigBee radio. Secondly, the Illumimote driver and light sensing application were programmed at the MicaZ mote using SOS environment. SOS is an OS for Mote-class wireless sensor networks developed by NESL at UCLA. Finally, at the base station laptop, a Java program was used to monitor and log the light measurements, and a visualization interface was used for real-time debugging and analysis. A GUI visualization interface was developed as shown below to display the status of the Illumimote in real time, that was used for testing, experimenting, and performing demonstrations. The interface was implemented in Java and Processing. This GUI made it easy to test and evaluate the Illumimotes visually and is a step towards designing the interface that could be used by a cinematographer in future.



The Illumimote achieves performance comparable to a commercial light meter and color meter (as used by professional cinematographers) over the ranges tested. It consists of incident light intensity, RGB intensity (for color temperature calculation capability), and incident light angle sensors as well as thermal and attitudinal sensors. Researchers at UCLA characterized its performance and verified its capabilities. The project website hosts the technical data and the Illumimote will soon be commercially available from Atla Labs to allow other researchers access to the technology for their own experimentation. Future work includes further enhancements to the general characteristics of the Illumimote (such as dynamic range), estimation of the vertical incident light angle, and further development of the software tools that support and integrate the Illumimote in support of its deployment on actual productions scheduled for the near future.

Heated up about your Energy Bill? Motes to the Rescue!

by Ralph Kling, Chief Architect, Crossbow Technology, Inc.

When I opened up my Gas and Electric bill from our local utility (PG&E here in Northern California) I was shocked: it was over $100 more than I expected. Some further checking confirmed that it was also substantially higher than during the same time last year, by about that amount. So what happened? Sure, energy prices likely have increased since last year and maybe it was a bit colder here the last month. But it still didn’t add up… 

A few years ago I had installed a shiny new programmable digital thermostat to replace an old mechanical gizmo that must have been around since the house was built in the 1950s. And I actually did read the manual (well, some of it anyways) and spent quite a bit of time programming it with different cycles for days and nights and weekends and so on. And, though I was very proud of that accomplishment at the time, the promised energy savings that I had hoped for actually never really materialized. My utility bills stayed pretty much the same before and after the thermostat installation. 

So after receiving the last bill, I investigated the thermostat but it seemed to work just fine and none of the settings had been changed since I had originally made them. After contemplating this for a bit, I had an idea. Since I am working at Crossbow, the leader in Wireless Sensing technologies I have access to the essential tools needed to solve this mystery: I took home a Wireless Sensor Starter Kit which consists of two sensor nodes and a base station. I also added a Stargate Netbridge gateway to record and visualize the data from the sensor nodes without the need to install anything on my PC (or even have it running and consuming energy during the measurements). 

The next day, I installed the “Sensor Network” in my house. It was really simple, just plug the gateway into my home router, place the sensor nodes in the rooms I wanted to monitor and turn them on. All networking and data gathering happen automatically from then on. The sensor nodes are battery powered thus they can be placed pretty much anywhere eliminating the search for outlets. I placed the nodes in the kids’ rooms in the center and back of the house. The nodes have all sorts of sensors including light, humidity, atmospheric pressure etc. but I was particularly interested in the temperature readings. 

The next day, I pulled up the temperature profile gathered so far and I was shocked:

 

The Thermostat was set to 70°F, (about 21°C) during the morning and evening and to 65°F, (18°C) during the rest of the day and at night. The measurements show an average of 24°C during the high and 20°C during the low period, a full 2-3 degrees more than expected. Why were the readings so far off from the preset values at the thermostat? And then it dawned on me: the thermostat was in the living room at the other end of the house. And I remembered that last year in the summer I had closed the heating air vents in that room to prevent the kids’ Lego pieces from falling into the shafts (they are really hard to retrieve from there). Of course I had forgotten about that in the fall when I restarted the heater. 

So the warm air had to make its way through half the house before the living room (and the thermostat) warmed up thus raising the temperature in the other rooms way to high (as well as the heating bill). But this was still a theory that needed to be proven. So I opened up the living room vents all the way, let the sensors collect more data and waited impatiently for the data from the next day. The results were nothing short of astounding:

 

The temperatures in the kids’ rooms now averaged 21°C during the high and 19°C during the low periods, much closer to the desired thermostat settings. Beyond that, the data also shows that one room warms up more poorly than the other (it has more outside walls with poor insulation). Adjusting the vents in those rooms as well could further equalize the temperature readings. 

So, with a very simple setup (it took literally 5 minutes to set up) I was able to gather a lot of valuable data and hopefully significantly reduce my heating bill (we will see next month). And all that without lowering the temperature settings on the thermostat! Beyond that there are lots more insights that can be gathered from the data: The slope between the day and night settings shows how fast the house cools down and how well it is insulated. Other data like the humidity measurements can point to potential problems with mold if the readings are too high. Do your kids always “forget” to turn off the lights – well a plot of the data can very convincingly show how much energy is wasted. 

I am sure there are lots more good ideas – reader’s suggestions are welcome!

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

Previously, Ralph was Principal Architect and Director of Sensor Network Operation at Intel Corporate Research. In this capacity, he was responsible for ground-breaking research in the area of Wireless Sensor Network Platforms that resulted in such novel designs as the Intel Mote and Imote2. Before joining Intel Research, Ralph's previous assignments include managing the Itanium® Processor Family microarchitecture/ performance group and the Microprocessor Research Lab (MRL).

Ralph obtained his Master's and Ph.D. degrees from the University of Illinois at Urbana-Champaign. His thesis research focused on Simulated Evolution, a new global optimization method for integrated circuit designs. Prior to coming to the US on a Fulbright scholarship, Ralph studied Electrical Engineering in his hometown of Hanover in Germany. He enjoys skiing in the winter and beaches in the summer.

TinyOS 2.0 Support for Crossbow's IRIS Mote Platform

Earlier this month, Crossbow announced the availability of the TinyOS 2.0 Operating System for Crossbow's advanced IRIS Motes. TinyOS 2.0 is the latest major release of the popular open source embedded operating system. This release now enables developers to use the latest generation TinyOS software on the latest generation Sensor Network hardware. TinyOS is an open-source operating system designed for wireless embedded sensor networks. It features a component-based architecture which enables rapid innovation and implementation while minimizing code size as required by the severe memory constraints inherent in sensor networks. The TinyOS component library includes network protocols, distributed services, sensor drivers, and data acquisition tools. The event-driven execution model enables fine-grained power management yet allows the scheduling flexibility made necessary by the unpredictable nature of wireless communication and physical world interfaces.

The IRIS Mote platform offers users excellent RF range (over 3x improved radio range of previous generation motes), substantially lower sleep current (50% of previous generations), and double the program memory (8KB). In conjunction with TinyOS 2.0, users now have a better hardware abstraction model, improved timers, sensor interfaces, power management, arbitration and much more. The IRIS Mote is a 2.4 GHz module used for enabling low-power wireless sensor networks and is also supported by Crossbow's MoteWorks software development environment based on open-source TinyOS.

The IRIS port was created by Vanderbilt University's Institute for Software Integrated Systems. Wireless sensor network developers and researchers benefit from Vanderbilt University’s well-established, recognized expertise in TinyOS development and continued support of released code. “We are pleased to have received Crossbow’s support for the advancement of the open source TinyOS 2.0 environment and continued development of leading edge wireless sensor network platforms,” said Professor Akos Ledeczi, Research Associate Professor and principal investigator on the project.

Crossbow is the leading provider of wireless sensor nodes, or motes, and continues to offer broad operating system choice. One or more Crossbow platforms are now supported on development environments including Contiki, Linux, LiteOS, Mantis, Microsoft .NET Micro Framework, MoteWorks, SOS, and TinyOS. “Crossbow’s ability to provide software choice enables rapid development of the newest and most innovative applications of wireless sensor networks,” said Robert Robinson, Vice President of Sales & Marketing for Crossbow’s wireless division.    

Instructions for download and use of Vanderbilt’s open-source code release of TinyOS 2.0 for IRIS are available here. Crossbow’s IRIS product line includes the IRIS OEM Module, IRIS Mote, and related sensor boards. Check out the IRIS platform and other Crossbow wireless sensor networking products here.

Wireless Soil Moisture Tension Measurements for Irrigation Management

Irrigation is defined as the artificial application of water to the soil usually for assisting in growing crops. In crop production it is mainly used in dry areas and in periods of rainfall shortfalls, but also to protect plants against frost. Irrigation management in agriculture and landscaping is of growing importance as the growing global population puts more demand on finite fresh water supplies. Managing irrigation optimally improves yields and quality while reducing water user and pumping energy costs. Optimal irrigation management requires reliable knowledge of plant water stress and soil moisture status. Many different devices and techniques have been used to gather this type of information, but perhaps none as successful as one of Crossbow's beta ēKo deployments in California's Napa Valley wine country.

Mark Holler is the owner of Camalie Vineyards in Napa, Califorina. He is a viticulturist and a technology enthusiast who has been working closely with Crossbow in the development and testing of the ēKo platform over the past two years to increase the quality and quantity of his grape harvest by using and controlling his water resources. With the data he collected from the ēko platform, Mark has been able to minimize his water use and maximize his yield despite the low water season we saw this past year in 2007. This achievement was not only due to the ēko system's ability to collect data, but Mark's ability to analyze the data and apply it to his growing techniques. Mark has written a white paper on High Density, Multiple Depth, Wireless Soil Moisture Tension Measurements for Irrigation Management. Below is an extract regarding his application and findings. To read the entire article click here:

When sampled sufficiently at appropriate depths soil moisture tensions were found to correlate well with pressure chamber measurements of midday leaf water potential in Cabernet Sauvignon grape wines. Sampling 2-3 sites per acre across a 4.4 acre hillside vineyard produced a substantial correlation of midday leaf water potentials to soil moisture tensions at 24" depth. The correlations were performed on soil moisture data and pressure chamber data from the 2007 irrigation season on the Mount Veeder hillside vineyard on the western slopes of Napa Valley. The data suggests that  soil moisture tension measurements may be able to replace many leaf water potential measurements which are significantly more labor intensive. A strategy for use of soil moisture tension measurements in manging regulated deficit irrigation of grape vines and the monitoring of other irrigation system parameters using the ēko Pro Series is described in this overview.

Correlations were done between leaf water potentials and soil moisture tensions acquired at 12" depth and 24" depth. Data from all locations and times were combined for these correlations. Sample size was 43 points per depth.The soil moisture data at 12” depth does not correlate with the leaf water potential measurements but, at 24” depth there is a “substantial” correlation.  This data suggests that deeper placements of the soil moisture sensors might produce better correlations with the leaf water potentials. 

From the data gathered one could also conclude that the vines were getting their water from deeper depths and that the vines have not concentrated their root growth around the sub surface dripper which is co-located with the soil moisture sensor at 12” depth. This information was useful in deciding not to move the subsurface drippers further from the vines or deeper to encourage root growth.This type of correlation could be used to optimize locations for soil moisture sensing. In an initial deployment many sensors could be placed at different depths at a few locations for the first season. At the end of the season correlations with leaf water potentials could be done and the root zone locations with best correlations determined. The following season more sites would be added with fewer soil moisture sensors per site only at the optimal location(s) in the root zone determined. 

The general success of the 2007 growing season at this vineyard in terms of yield, ripeness and reduced water use supports the use of the modified regulated deficit irrigation though indirectly because there are many confounding factors which affect yield. In 2006 data from the soil moisture sensors was used to optimize irrigation durations and intervals. Soil moisture sensors provide good insight into how water moves within the soil – hydraulic transport, something that leaf water potentials cannot provide. The delay between wetting at 12” depth and 24” depth is a measure of how long it takes water to move downward within the soil. From this the vertical hydraulic conductivity can be inferred. The slope of the drying transient indicates how fast water is moving away from the sensors either due to diffusion or plant uptake. 

Irrigation durations and intervals were optimized to achieve desired average soil moisture at 24” depth. This soil moisture target was based on leaf water potentials as described above. Total available water supply for the season was also considered. We adopted the premise that the vines benefit from reduced variability in soil moisture over time. The best uniformity over time would be achieved by very short durations at frequent intervals. Short durations and frequent intervals, however, do not allow the water to penetrate very far between irrigations. Short intervals also result in non-uniformities across each block because the line pressures are below spec for constant drip rate during start and stop transients. The total start up and shut down transient time for this irrigation system was determined to be about 30 minutes. We set the minimum irrigation duration to 2 hours to make the transient effects less than 25% of the irrigation duration. We then checked to see that the water was reaching the 24” deep sensors consistently with an interval equal to the time it took the 24” depth to dry out to the level before the last irrigation. The interval was then varied to bring the average soil moisture level at 24” depth to the target value. We then looked at the water consumption rate of our optimized duration/interval times and forecasted total use for the season.

If this use was in excess of our water resource we lengthened the interval to the consumption rate we could afford. We then monitored the new average soil moisture and spot checked leaf water potentials to determine if we could keep the vines from becoming over stressed. If the leaf water potentials continue to drop to –15 bar and beyond as was the case in the 2007 season we purchased additional water and trucked it to the vineyard. In 2007 in light of a very dry winter rainfall we delayed irrigation until a higher stress level was achieved to reduce canopy growth and subsequent water consumption by the vines. Our yield and fruit maturity results suggest that this was a good approach. We feel strongly that high water stress transients during the growing season can damage the vines not only in the short term but over several seasons as well.

Camalie used a prototype network during the 2005 and 2006 growing seasons to guide irrigation decisions in the 4.4 acres of Camalie Vineyards. Yield per vine in 2005 was double that of the 2004 yields for same age vines yet the water consumption was kept constant.  Typically water consumption goes up with canopy size which more than doubled for these 2.5 year old vines in 2005. The grape quality was excellent. Of course, some of this success was due to generally better than average weather in 2005 but, Mark and others at Camalie believe their visibility of the soil moisture played a significant role.  Extra drippers were added to some areas of the vineyard based on the soil moisture data.   Also irrigation intervals were shortened based on sensor data to reduce the amount of water that penetrated below the root zones where it would be wasted. In 2006, the third year for their vines, the yields again doubled from 4 tons to 8 tons. In the 4th year, 2007, the network was upgraded to the latest Crossbow technology, the yield again doubled to 16 tons of fruit that was sold and another 1.5 tons that the vineyard made into wine themselves. The yield was 3.97 tons per acre which is very rare on Mt. Veeder especially with water limited due to less than half the normal rainfall in the winter of 2006/07.  Water had to be purchased but thanks to their precision irrigation the vineyard minimized water purchasing and still had great yields.  Fruit quality was excellent as before.

For more insight into the methodology used at Camalie Vineyards, be sure to read the complete white paper here.

 

ēKo series wireless crop monitoring system unveiled

On Tuesday of this week, Crossbow announced the release of ēKo™ Pro Series, a turnkey live data, wireless crop monitoring system enabling precision agriculture. The ēKo Pro Series follows Crossbow’s already popular sensor and navigation solutions for heavy agricultural equipment. See the video below for additional details.

ēKo™ represents the next generation in crop monitoring and precision agriculture techniques, employing a mesh network of wireless sensors and providing vital live data about crop health, vigor and growth progress via a simple internet browser. Among others, the ēKo Pro Series monitoring solution features the following innovations:
• Solar-powered, field-deployed wireless sensor nodes, which require no electrical power so that sensors can be placed where needed.
• Simple-to-use, web-based data viewing that allows remote access to live sensor data, critical trend charts and alarm settings - all of which are highly customizable.
• Leading-edge, reliable wireless mesh network technology that is self-configuring and self-healing, thus providing effortless setup and easy scalability, where additional wireless nodes and sensors can be added easily by non-technical users.

ēKo Pro Series drives increased profits and competitive advantage by enabling lower input costs, mitigating crop loss risks, increasing per-acre yields, and delivering higher quality crops with greater consistency.

“ēKo Pro Series enables growers to consistently improve yield and quality regardless of the variability in the terrain, soil or micro-climates,” said Robert Robinson, VP of Sales and Marketing at Crossbow. “Growers can now overcome the traditional trade off between higher yields vs. higher quality and can achieve a higher average price on larger harvests consistently by executing precision agriculture techniques with ēKo Pro Series data."

ēKo eliminates concerns about reliability and complexity in applying wireless technology to deficit irrigation and precision agriculture by delivering a more integrated solution including all the sensors, software application, sensor nodes, and network components that growers need to quickly and easily deploy a wireless monitoring system.

“ēKo takes crop monitoring using wireless technology to whole new levels in terms of reliability,  flexibility, and ease,” said Alan Broad, Director of Environmental Products at Crossbow. “Its mesh based architecture with capabilities such as data re-routing, self-organizing/self-healing network, autodetection of new nodes delivers proven reliability, effortless deployment, and easy scalability. Moreover, the unique sensor interface provides the flexibility to add any sensor from third-party vendors in the future."

The ēKo Pro Series Starter Kit provides a quick, easy way to get started with wireless monitoring. It includes an ēKo Pro Series Network Gateway, 3 ēKo Pro Series wireless nodes, 6 soil moisture/ temperature sensors, 1 ambient temperature sensor, and built-in web-based monitoring application. Additional wireless nodes and sensors are simple to add. The new ēKo Pro Series will begin shipping in volume in April 2008. Pricing and advanced sales inquiries may be directed to sales@xbow.com. Crossbow previewed the ēKo Pro Series at the Unified Wine & Grape Symposium in Sacramento, California on January 29-31 this week. To learn more about the use of ēKo for wireless crop monitoring, visit www.xbow.com/eKo.

Solutions for Structural, Landslide and Bridge Monitoring

Seeing the images on TV yesterday about the tragedy in Minneapolis surrounding the collapse of the I35W Bridge has raised many concerns nationwide regarding the structural integrity of the bridges we drive on each and every day. As a Bay Area company located on a peninsula in a crowded area, many Crossbow employees traverse the Bay Bridge, Golden Gate Bridge, Third Street Bridge, High Street Bridge, etc... to get to/from work. In a recent article published in the San Francisco Chronicle, we have been informed that 800 of the Bay Area's spans are rated the same as the fallen I35W Bridge. Although Caltrans has stated that 'structurally deficient' does not necessarily mean that the road is in danger of collapse, many people are left wondering about the structural integrity of the roadways we drive over on a daily basis. In California, 13% of the 23,000 bridges have been deemed structurally deficient, while 12% of the nation's 600,000 bridges share the same rating. The term can refer to anything from the paint peeling, having too many potholes, to the worst case scenario of failure.

What can be done to detect failure before it happens? In California, this is a serious issue due to the fault lines that run all over the state.  Most bridges must have had a seismic retrofit; however, is there a way to detect the early signs of structural stress? Crossbow has been working to address similar issues with our wireless sensor networks. A deployed network can provide predictive maintenance data to ensure that the correct personnel are notified immediately should any sign of deficiency be found. This technology has been used for landslide monitoring applications and this same technology can be used for monitoring bridges.

Hong Kong has a history of annual landslides. The terrain is steep and hilly with intense seasonal rainfall and very dense development on the hill slopes. Many of these slopes are prone to failure during the heavy rainfall. The ability to monitor the structure, in this case the mountain, provides valuable data to ensure that this natural hazard can be prevented or minimized. In the past 50 years, more than 470 people have been killed by landslides, and on 2 days alone, during severe rainstorms, 148 lives were lost. Hong Kong is one of the most densely populated cities in the world and the Hong Kong government has made a concerted effort to undertake landslide preventative measures whether it is identifying slopes at risk, or carrying out remediation works to monitor their geotechnical parameters including groundwater conditions.

For monitoring applications such as landslides or bridges, wiring is difficult and power supply is usually not available. A wireless and easy deployment solution is required by users. Crossbow's wireless sensor mesh network and its capability to link to the local GSM mobile phone network make it a successful solution for these applications. Crossbow's team in China has been working with the local government and local geotechnical instrumentation specialists to set up the system. In this deployment at a previous landslide site, several holes were drilled into mountain and a number of sensors, such as water level sensors and tilt sensors were placed in each hole to predict the possibility of a landslide. Sensors in each hole sampled at 3-10 minute intervals. Each sensor was interfaced to Crossbow's IRIS Mote platform through the MDA300 data acquisition board. These sensor readings were transmitted via the mesh network to the Stargate base station. The Stargate would then relay the data to a central location through the Hong Kong GSM mobile phone network. The IRIS Motes were powered by regular AA batteries and the Stargate was powered by a rechargeable battery and solar cell. The sampling rate was adjusted depending on the weather conditions to monitor the underground water level and the mountain's movement at each layer.

If a landslide is coming, the water level would typically rise first and the tilt sensors placed at the different depths would be able to report the changing angles in the slope's layers to warn about the impending disaster thus giving authorities time to vacate the area or take preventive measures. The ability to use a wireless sensor network in these scenarios could ensure the safety of many lives and homes. This monitoring solution can be applied to bridges, structures, machinery, etc. Sensors can be embedded at different support joints, truss systems, columns, stress areas, etc. and be interfaced to the Mote platforms to enable the wireless collection and transmission of data. Constant monitoring would definitely give me a little more peace of mind between the scheduled inspections and the potential changes that may occur in these structures.