At the IEEE Reconfigurable Architectures Workshop in Rome, Italy, on May 25, computer scientists from the Jacobs School of Engineering presented a paper highlighting the energy conservation benefits of using reconfigurable hardware rather than competing hardware platforms for their experimental underwater sensor nets.
“We are building a low-cost, low-power modem for short-range, low data-rate underwater networking. Working underwater means you don’t have access to a wall socket for plug-in power. Our idea is to make the sensor and modem hardware as energy efficient as possible,” said Benson.
Greater energy efficiency means batteries can last longer and the sensors can sample the environment more frequently. Higher sampling rates can greatly increase the utility of the collected data and enable scientists to plan experiments when the conditions are just right.
Networks of underwater sensors could also serve as “stepping stones” that provide a way for data collected from underwater sensors to get back to land without any one sensor having to send a signal a long distance, which is costly in terms of energy consumption.
Reconfigurable hardware rises to the top
The computer scientists studied the patterns of energy consumption of underwater modems and determined that, for short distances, the hardware platform is a big power drain. With this in mind, the researchers looked at three different hardware platforms: digital signal processors, microcontrollers, and reconfigurable hardware. Their tests—described in the paper presented at the IEEE Workshop in Rome—show that the reconfigurable hardware platform provides the best low-energy implementation for the particular underwater communications algorithm they implemented.
“The amplifier works, but it is not yet as efficient as Don Kimball’s original design or the early simulations,” said electrical engineering undergraduate Brian Faunce, referring to Calit2 principal development engineer Don Kimball. “There is some sort of an optimization issue we still have to figure out.” “The impedance of the underwater transducer is much more complex than we originally thought” says Kimball.
“In class, you learn a lot of theory, but you don’t learn how to revise a schematic, layout the printed circuit board, assemble the circuit and then perform field tests. I have friends at other schools, and when it comes to internships and projects, they are just not available at other schools the way they are here,” said Faunce.
“Sensor networks are revolutionizing the way we understand our natural world. Unfortunately, the advances in the underwater sensor networks have not matched those in the terrestrial domain,” said Kastner, a professor in the Department of Computer Science and Engineering (CSE) at the Jacobs School.
Sensor Nets and Diving Vets
If scientists had underwater sensor nets, they could keep better tabs on how water conditions are changing. For example, Benson is working with researchers at an ecological research station in Tahiti that includes underwater sensors. However, the data from the sensors is only available every six months, when a diver manually goes down to the sensor and downloads that data.
In addition to creating sensor nets, these modems could be used to send data to autonomous crafts on the water’s surface. Researchers at UCSD’s Calit2 led by Doug Palmer, principal development engineer, are working on such a craft, Reef Bot.
Closer to home, Benson had first hand knowledge of how sensor nets could be useful for monitoring California’s rocky reefs. Outside of school, Benson serves as the Southern California volunteer coordinator for the nonprofit organization Reef Check. Benson oversees the training of veteran divers to conduct surveys of the species living in reefs from Santa Barbara to San Diego.
“Our volunteers learn how to identify fish and other organisms and learn what protocols we use. Once they are certified, the volunteers go out and help us do the surveys,” said Benson, who will oversee a survey in Palos Verdes (between Santa Monica and Huntington Beach) on June 6 and 7. Other volunteers from Reef Check will do a similar survey in La Jolla Cove on May 30.
“I have the field experience, and I see the need for the cheap sensor networks we are working on,” said Benson, who envisions a future where volunteers and autonomous robots work together to monitor the health and species richness of reefs and other underwater ecosystems.
“Energy Benefits of Reconfigurable Hardware for Use in Underwater Sensor Nets,” IEEE Reconfigurable Architectures Workshop (RAW), May 2009 by Bridget Benson, Ali Irturk, Junguk Cho and Ryan Kastner from the Department of Computer Science and Engineering at UC San Diego’s Jacobs School of Engineering.
Bridget Benson is supported by a National Science Foundation (NSF) Graduate Research Fellowship. This project is supported by NSF grant CNS-0839944.
Daniel Kane | EurekAlert!
21.08.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau
AI implications: Engineer's model lays groundwork for machine-learning device
18.08.2017 | Washington University in St. Louis
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
21.08.2017 | Materials Sciences
21.08.2017 | Health and Medicine
21.08.2017 | Materials Sciences