MicroStrain announced that its energy harvesting wireless strain sensing modules have been released for sale. The company asserts its sensing systems will operate indefinitely -- without the need for batteries -- by converting the component’s cyclic strains into DC power using piezoelectric materials. The miniaturized energy harvesting sensing nodes, called ESG-LINK, feature a precision time keeper, non-volatile memory for on-board data logging and frequency agile IEEE 802.15.4 transceiver. Sampling rates, sample durations, sensor offsets, sensor gains and on-board shunt calibration are all wirelessly programmable. Recent flight tests on a Bell Helicopter Model 412 has shown that MicroStrain’s nodes will operate continually, without batteries, even under low energy generation conditions of straight and level helicopter flight. This was, to the company’s knowledge, the first successful flight test of a wireless, energy harvesting sensor on rotating helicopter components. MicroStrain’s latest adaptive energy harvesting wireless sensors can sample pitch link static and dynamic loads at a rate of 32 samples/sec., then communicate these wireless data into the helicopter cabin while consuming 250 µW compared to conventional Wheatstone bridge signal conditioning electronics (which draw 72 mW) -- an improvement of 288-fold.