James Prescott Joule
research :: energy management

Prabal Dutta
410 Soda Hall #1776
Computer Science Division
Berkeley, California 94720

prabal   cs . berkeley . edu
(510) 643-3327 (Office)



Overview Energy is the critical resource of our time and its careful management is a key challenge facing engineers across the entire EECS spectrum from nanopower chip design to micropower system design to kilowatt server design to megawatt power distribution. Our energy management research seeks to: (i) understand when, where, and how energy is used; (ii) identify opportunities to better manage energy use; and (iii) develop hardware and software to enable energy-efficient operation. Our recent research efforts have focused on techniques for energy metering, tracing, harvesting, and management.
Projects    
Quanto Software and Hardware. Quanto is a tool for energy profiling in networked embedded systems. It builds on the iCount energy meter and combines well-defined interfaces for hardware power state visibility, regression for per-hardware subsystem energy breakdown, and programmer-defined causal activity tracking using labels, to map how energy and time are spent on nodes and across a network. The Quanto Testbed Mote is designed to specifically to support energy tracking. It includes iCount, calibration circuitry for five orders of current draw, a Berkeley Epic Core mote module, a Digi Connect ME Ethernet backchannel, and true 802.3af Power-over-Ethernet support.



iCount Energy Meter. iCount is new energy meter design that measures energy usage by counting the cycles of a switching regulator. In most cases, this requires adding just one wire between the regulator and a microcontroller counter. This implementation exhibits an error of less than +/-20% over five decades of current draw, a resolution exceeding 1 uJ, a read latency of 15 us, and a power overhead that ranges from 1% when the node is in standby to 0.01% when the node is active, for a typical workload.



Benchmark Mote. The Benchmark mote is a largely Telos form factor-compatible platform for sensornet testbeds with a USB interface, application energy metering using iCount, and a 128K FIFO buffer for collecting and streaming high-frequency data.



Energy Management Architecture. The Energy Management Architecture enables graceful degradation and run-time adaptation of the sensornet (by allowing prioritized specification of user requirements), and allows the end user to declaratively express his/her requirements (such as sampling rate and lifetime).



SPOT Energy Meter and MicaZ adapter/storage board. SPOT enables in situ measurement of nodal power and energy over a dynamic range exceeding four decades or a temporal resolution of microseconds. Using SPOT, every node in a sensor network can be instrumented, providing unparalleled visibility into the dynamic power profile of applications and systems.



Trio Node (link: electronics), Network, and Multi-Target Tracking application.

Publications
  1. "Quanto: Tracking Energy in Networked Embedded Systems",
    Rodrigo Fonseca, Prabal Dutta, Philip Levis, and Ion Stoica,
    In Proceedings of the Eighth USENIX Symposium on Operating System Design and Implementation (OSDI'08), Dec. 8-10, 2008.

  2. "Energy Metering for Free: Augmenting Switching Regulators for Real-Time Monitoring",
    Prabal Dutta, Mark Feldmeier, Jay Taneja, Joseph Paradiso, and David Culler,
    In International Symposium on Low Power Electronics and Design (ISLPED'08) Design Contest, Aug. 2008. Design Contest Winner.

  3. "Energy Metering for Free: Augmenting Switching Regulators for Real-Time Monitoring",
    Prabal Dutta, Mark Feldmeier, Joseph Paradiso, and David Culler,
    In Proceedings of the Seventh International Conference on Information Processing in Sensor Networks (IPSN'08) Track on Sensor Platforms, Tools, and Design Methods (SPOTS '08), Apr. 2008. Best Paper Award.

  4. "Procrastination Might Lead to a Longer and More Useful Life",
    Prabal Dutta, David Culler, and Scott Shenker,
    In Proceeding of the Sixth Workshop on Hot Topics in Networks (HotNets-VI), Atlanta, GA, Nov. 14-15, 2007.

  5. "Micro Power Meter for Energy Monitoring of Wireless Sensor Networks at Scale",
    Xiaofan Jiang, Prabal Dutta, David Culler, and Ion Stoica,
    In Proceedings of the Sixth International Conference on Information Processing in Sensor Networks (IPSN'07) Track on Sensor Platforms, Tools, and Design Methods (SPOTS '07), Apr. 2007.

  6. "An Architecture for Energy Management in Wireless Sensor Networks",
    Xiaofan Jiang, Jay Taneja, Jorge Ortiz, Arsalan Tavakoli, Prabal Dutta, Jaein Jeong, David Culler, Philip Levis, and Scott Shenker,
    International Workshop on Wireless Sensor Network Architecture (WSNA'07), Apr. 2007.

  7. "Trio: Enabling Sustainable and Scalable Outdoor Wireless Sensor Network Deployments",
    Prabal Dutta, Jonathan Hui, Jaein Jeong, Sukun Kim, Cory Sharp, Jay Taneja, Gilman Tolle, Kamin Whitehouse, and David Culler,
    In Proceedings of the Fifth International Conference on Information Processing in Sensor Networks (IPSN'06) Special track on Platform Tools and Design Methods for Network Embedded Sensors (SPOTS '06), pp. 407-415, 2006.

  8. "System Software Techniques for Low-Power Operation in Wireless Sensor Networks",
    Prabal K. Dutta and David E. Culler,
    In Proceedings of the 2005 International Conference on Computer-Aided Design (ICCAD'05), pp. 925-932, 2005.

Patents / Applications
  1. "System and Method for Detecting a Proactive Device has Limited or Interrupted Current it Carriers",
    Prabal Dutta, Wei Hong, David Culler, and Malay Thakar, 2008 (pending).

  2. "System and Method for Dispatching a Technician to a Protective Device",
    Prabal Dutta, Wei Hong, David Culler, and Malay Thakar, 2008 (pending).

  3. "Method and Apparatus for Managing Power Distribution Equipment Using Remote Data Collection",
    Prabal Dutta, David Culler, Wei Hong, and Malay Thakar, 2007 (pending).



Prabal K. Dutta
Computer Science Division
Department of Electrical Engineering and Computer Sciences
The University of California, Berkeley
Soda Hall #1776, Berkeley, California 94720