Location: Quality and Safety Assessment Research Unit
Project Number: 6040-44000-001-000-D
Project Type: In-House Appropriated
Start Date: Jun 11, 2015
End Date: Jul 5, 2018
Objective:
1. Enable new commercial sensor-in-system flowing-grain microwave moisture and density meters for precision farming and yield monitoring.
2. Enable a portable, commercial microwave meter to create capacity for rapid grading in-shell almond and peanut by determining moisture content, meat content, and foreign material contents.
3. Enable new commercial microwave sensors for monitoring controlled drying of grain, peanuts and other seeds.
Approach:
I: To enable a new commercial sensor for flowing grain microwave moisture and density, dielectric-based algorithms for bulk density and moisture content determination at microwave frequencies will be tested in flowing situations. In designing a flowing-grain system, the frequency must be higher than 3 GHz, free-space transmission techniques will be used for on-line applications, and measurements will be performed in the near field to keep the system compact. At least three cultivars each of wheat, corn, and soybeans will be obtained from certified seed with some geographic and seasonal diversity. Moisture, density, and temperature will be varied for model development and then validated on flowing grain. Next, a prototype sensor made with off-the-shelf components will be assembled and tested. Then a user-friendly, step-by-step software programs will be developed to control the measurements with moisture predictions within 0.2% to 0.5%, and bulk density will be within less than 2% relative error.
II: The above system will next be developed for rapid grading of in-shell almond and peanut by determining moisture content, meat content, and foreign material contents. First dielectric properties data will be collected with laboratory grade instrumentation on un-cleaned and cleaned in-shell almonds and peanuts of different varieties and from different locations and compared to oven-drying moisture and meat content. Measurements will also be collected on almond and peanut kernels alone. The data will comprise of dielectric properties corresponding to frequency, temperature, moisture content, bulk density, meat content, and foreign material content. The next step is to develop a microwave prototype for moisture content, meat content, and foreign material content in in-shell almonds and peanuts which will be externally controlled with a laptop computer and ultimately packaged to satisfy grading requirements and withstand working conditions at buying stations.
III: The last approach is to use the microwave moisture sensors developed above to monitor and record moisture content of grain, peanuts and other seeds in real-time during drying while improving efficiency through control of drying and minimizing energy consumption when compared to existing drying controls. To accomplish this, a microwave moisture meter will be combined with three temperature sensors and a relative humidity sensor to monitor peanut drying in a quarter scale-model drying wagon to optimize the drying process by determining real time in-shell kernel moisture content in different zones of the trailer. Similar work will be performed with cereal grains and oilseeds stored and dried in large, farm storage bins. Varying temperature and moisture profiles will be evaluated during the drying process. Through feedback control, the system will optimize the drying process to better ensure even drying throughout the trailer (for peanuts) and bin (for grains). Once successful, the microwave moisture meter(s) will then be integrated with all other sensors in one single unit including a microcontroller, an LCD, and mass storage device.
