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The Floating Sensor Network project, led by associate professorAlexandre Bayen, a researcher at the Center for InformationTechnology Research in the Interest of Society (CITRIS), offers anetwork of mobile sensors that can be deployed rapidly to providereal-time, high-resolution data in hard-to-map waterways. One areathat stands to benefit from this technology is the Sacramento-SanJoaquin River Delta, with its complex network of channels thatdirect drinking water to two-thirds of California's population andirrigation water for 3 million acres of agriculture. Having a high volume of sensors moving through the water can shedlight on processes that are influenced by how water moves, such asthe spread of pollutants, the migration of salmon or how salt andfresh water mix in the Delta's ecosystem, the researchers said.Today's field test gave researchers a picture of how water movesthrough a junction in the river with a resolution never beforeachieved. "We are putting water online," said Bayen, who holdsjoint appointments in UC Berkeley's departments of electricalengineering and computer sciences and of civil and environmentalengineering. "Monitoring the state's water supply is criticalfor the general public, water researchers and government agencies,which now rely upon costly fixed water sensor stations that don'talways generate sufficient data for modeling and prediction. Themobile probes we are using could potentially expand coverage in theDelta -- on demand -- to hundreds of miles of natural and humanmadechannels that are currently under-monitored, and help agenciesresponsible for managing the state's limited water supply." Such a flexible system could be critical in the event of anemergency, including a levee breach or oil spill, the researchersnoted. The sensors could be thrown into action from a dock, shore,boats or even helicopters. "If something spills in the water, if there's a contaminant,you need to know where it is now, you need to know where it'sgoing, you need to know where it will be later on," saidAndrew Tinka, a Ph.D. candidate in electrical engineering andcomputer sciences and the lead graduate student on the project."The Floating Sensor Network project can help by trackingwater flow at a level of detail not currently possible." The May 9 launch in Walnut Grove, Calif., marked a milestone in theproject, which is supported by CITRIS and the Lawrence BerkeleyNational Laboratory (Berkeley Lab). It was the first timeresearchers deployed their full arsenal of floats, each equippedwith GPS-enabled mobile phones encased in 12-inch-long watertightcapsules marked with fluorescent tape. The researchers wrotespecific programs to run on the open source platforms used in therobots and on the smartphones. The project is an evolution of earlier research led by Bayen calledMobile Century and Mobile Millennium, which uses GPS-enabledsmartphones to monitor traffic flow. Instead of a map of traffic,the Floating Century mobile probes created a map of water flow. Every few seconds, the phones in the floats transmitted locationdata back to servers at Berkeley Lab's National Energy ResearchScientific Computing Center (NERSC), where the data was assimilatedusing a computer model called REALM (River, Estuary and LandModel). Information was processed to create a map that allowedresearchers to track the devices on their computer monitors. "Not only is this project interesting from a data collectionperspective, but it also presents a new challenge for us on thedata processing side," said Shane Canon, head of theTechnology Integration Group at NERSC. "While the total amountof data is not unusual, the streaming rate is higher than weusually see, and the researchers are looking to access the data innear real-time." The REALM model was developed by researchers at the Berkeley Laband the California Department of Water Resources. It was laterexpanded to integrate data from mobile robots by Qingfang Wu, a UCBerkeley graduate student in civil and environmental engineering. "Part of the novelty of this project is the use of the NERSCcomputer cluster to run large-scale data assimilationproblems," said Wu. "The floating sensor project demandsthe ability to process hundreds of parallel versions of REALM andintegrate the results into an estimate of the hydrodynamics of theDelta." Although the sensors in the test were set up to monitor the speedof water currents, the researchers said the floats could beequipped with sensors for a variety of measurements, includingtemperature, salinity, or a contaminant of interest. Of the 100 floats in the fleet, 40 were autonomous devices fittedwith propellers to help them move around obstacles or targetedareas. "The major constraint on floating sensors in inlandenvironments is their tendency to get stuck on the shores,"said Tinka. "Currently, using floating sensors requires closehuman supervision. We are developing autonomous, actuated sensorsthat can use propulsion to avoid obstacles." The Floating Sensor Network's fleet of robots includes prototypeswith advanced capabilities, including models that can dive belowthe surface of the water, versions equipped with salinity sensorsto measure the water quality in rivers, and versions with depthsensors that can map out the shape of the channels in which theyfloat. "Our development efforts show the versatility of thistechnology and how it can adapt to the challenges faced indifferent applications," said Bayen. "For example, thecapability to measure depth is particularly important in situationswhere it is impractical or dangerous to send personnel to do thejob, such as in military operations in combat zones. Floatingsensor fleets also provide capabilities which can be used toimprove our understanding of the shape of domestic rivers anddeltas." The floating sensor network has been tested in collaboration withthe U.S. Department of Homeland Security and the U.S. Army Corps ofEngineers to assess water discharge downstream from broken levees.The researchers are also planning a deployment to monitor theecosystem of Lake Tahoe in the coming months. Floats are retrieved at the end of experiments, but the researchersacknowledged the possibility that devices can get lost. Theresearchers said they expect the expense of individual sensors togo down with continuing advances in mobile communications so thatthe system can better tolerate a certain level of device dropout. "In the future, cost and size will go down, while performanceand autonomy will go up, enabling monitoring at unprecedentedscales," said Bayen. "We expect this to become aninvaluable tool for the future management of a critical resource inthis state and around the world.". The e-commerce company in China offers quality products such as Digital Printed Fabric , China Embroidered Lace Fabric, and more. For more , please visit Metallic Lace Fabric today!
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