The program is written in our Eon language, with a runtime system designed for solar charging.

Sources for the Eon compiler, adaptive runtime system and turtle program as well as our hardware designs are available here.


We initially used the following hardware in the Turtle nodes:

  • SiRF Star III-based GPS Receiver pulled out of a Deluo receiver
  • Ultralife UBC581730 250 mAh Battery
  • XBow Mica2Dot Mote
  • Custom designed charging board.   Schematics available.  If you want board layouts, etc, please contact us.
  • 4.2V powerfilm flexible solar cells
  • The node is packaged in shrinkwrap tubing and the ends are sealed with 30 minute, waterproof epoxy

In later deployments we have made the following improvements:

  • Replaced Mica2Dot with a TinyNode (Shockfish) to increase radio performance. 
  • Charge board upgraded to accomodate the TinyNode.
  • Use higher-efficiency 6V solar panels from Solarbotics (SCC3733).
  • Custom plastic enclosure, sealed with epoxy.


Hardware notes:

  • Many elements of the hardware design were borrowed from the HelioMote project.
  • The mote turns on when the battery reaches 3.6V, and turns off when the battery reaches 3.1V (hysteresis)


Hamed Soroush, Nilanjan Banerjee, Aruna Balasubramanian, Mark D. Corner, Brian Neil Levine, and Brian Lynn. In Proc. ACM Intl. Workshop on Hot Topics of Planet-Scale Mobility Measurements (HotPlanet), June 2009. PDF
Aruna Balasubramanian, Brian Neil Levine, and Arun Venkataramani. IEEE/ACM Transactions on Networking, 18(2):596--609, April 2010. PDF.
Nilanjan Banerjee, Mark D. Corner, and Brian Neil Levine. IEEE/ACM Transactions on Networking, 18(2):554--567, April 2010. PDF
Architecting Protocols to Enable Mobile Applications in Diverse Wireless Networks. Aruna Balasubramanian. PhD thesis, University of Massachusetts Amherst, Amherst, MA, February 2011.
System support for perpetual mobile tracking Ph.D. Thesis. Univ. of Massachusetts Amherst
Improved Network Consistency and Connection in Mobile and Sensor Systems Ph.D. Dissertation, University of Massachusetts, Amherst, September 2009 Winner of the 2009 UMass/Yahoo! Outstanding Dissertation Award!