SBIR-STTR Award

An innovative piezoelectric sensor and its associated electronics for the measurement of mass flux of wind eroding soil is described here. By use of a ring shaped and radially polarized piezoelectric sensor, wind direction invariance has been achieved. The momentum of a particle is proportional to the charge generated as a result of compressive stress within the crystal upon the particle's collision. The sensor has been designed to respond to the momentum range of 2.6 x 10-12 to 8.9 x 10-7g-M/S. This corresponds to particles having a diameter range of 100 to 1500 micrometers traveling at velocities of 2.0 to 20 M/S, the main constituent of wind eroded soil. Calibration of the sensor over this momentum range utilizing assorted sized particles traveling at known velocities is proposed herein.Applications:Agriculturally oriented wind erosion monitoring will constitute the main application of this instrument. Several other applications are: Sand dune movement in desert areas, blowing snow and ice mass movement, abrasion warning for sensitive optical equipment such as exposed lens or solar mirrors, silt transport measurement from tributaries to reservoirs, and underwater sand movement along coastlines and inlets.

A new and innovative field instrument and method for the measurement of wind eroding soils is proposed herein. The instrument has no moving parts, requires no maintenance and operates indefinitely by solar power. The sensor is a ring shaped, radially polarized manmade piezoelectric crystal suspended in soft anti-vibration rubber mounts as a section of a vertical post. The crystal produces a charge proportional to the imparted kinetic energy of impacting particles. The phase I study has shown the new instrument responds properly to particles of known velocity released in a laboratory testing apparatus. Phase II will develop an algorithm for the calculation of average particle velocities as a function of height (imperative for the calculation of mass from kinetic energy) within the saltation layer of an eroding medium through extensive field testing. The phase II research will also provide analysis of the instrument capability to obtain high quality erosion data for a variety of soil types in locations of different climatic conditions. The combined phase I laboratory and phase II field efforts complete a solid scientific foundation supporting the instrument's commercial potential.Applications:Agriculturally oriented wind erosion monitoring will constitute the main application of this instrument. Commercial applications include; soil movement, crop damage assessment, dust pollution source management, tillage and barrier effectiveness, sand dune movement, vegetation effects, movement of toxic material dump areas, wind erosion equation modeling, verification of soil erosion claims, and air driven material transport mechanisms etc.