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Wireless sensor networks can be extended to include numerous different sensing devices. Strain gauges are the most common nondestructive sensing elements for measuring surface strain. This paper discusses the design, for the wireless CiNet network, of a strain gauge measurement system, which would make strain measurements more flexible while opening new targets of application in addition to those that traditional wired strain measuring systems can offer. The calibration and validation of the wireless strain measurements as well as energy consumption issues are also brought under observation.

In this paper, we report the sensor function design and implementation of a wireless sensor network application for measuring environmental acoustic noise. The system is built on ATmega128 and CC2420 platform. The protocol stack is based on CiNet stack with a global synchronization scheme and supports multi-hop communications. Strict filtering function specified by ITU-R 468 (namely A-weighting) is followed. Both the indoor and outdoor test results were compared with standard sound level meters (CESVA SC-20c and Pulsar94) and showed a less than ±2dB error in both short-term and longterm measurement. Power consumption has been measured that a single AA-type battery can sustain the application. Comparing to the traditional noise measurement method, our wireless sensor network solution is much lower in cost, able to offer real-time data with sensed data timely coherent, and requests least attention after deployment.