The idea of using Lagrangian drifters for atmospheric sampling has been prevalent for more than 50 years. Substantial reductions in platform mass, size, and cost can now be realized by leveraging current and expected advances in micro- and ultimately nanotechnology. Such advancements have inspired a new observing system called Global Environmental Micro Sensors (GEMS). The initial GEMS concept envisioned developing and deploying large numbers of devices as small as 50–100 μim in one or more dimensions.
The GEMS concept was evaluated during a multiyear study from 2002 to 2005 for the NASA Institute for Advanced Concepts. The current GEMS prototype features a 1-m, super-pressure balloon filled with helium to make it neutrally buoyant at different levels in the atmosphere. Once deployed, the probe measures temperature, pressure, relative humidity, velocity, and position information using microsensors as it drifts passively with the wind.
Field experiments with GEMS prototypes were conducted in 2007 for a project called GEMS Test Operations in the Natural Environment (GEMSTONE). The success of the single-probe free flight test lasting more than 7 h fell short of the project goal but demonstrated system functionality and robustness. Follow-up efforts will address issues identified during the GEMSTONE project to feature multiprobe flight tests where probes travel hundreds of kilometers for several days. Significant reductions in mass and size of GEMS can be achieved through miniaturization/integration of probe components as well as advances in material sciences and bio-inspired designs.
AWS Truewind, LLC, Albany, NY
ENSCO, Inc., Melbourne, Florida
BioForce NanoSciences, Inc., Ames, Iowa
Cypress Semiconductor Corp., San Jose, California