Grain Bin Entrapment Pressure Measurement Kevin Moore Biosystems

Grain Bin Entrapment – Pressure Measurement Kevin Moore Biosystems and Agricultural Engineering Oklahoma State University

Grain Bin Entrapment • Entrapment – an individual is trapped inside a grain storage structure and cannot free themselves • Causes • • Flowing grain Collapse of “bridged” grain Collapse of vertical grain wall Failure of storage structure http: //www. ag. ndsu. edu/pub s/ageng/safety/ae 1102. pdf

Grain Bin Entrapment http: //extension. entm. purdue. edu/grainlab/content/pdf/2013 Summary. Final. pdf

Grain Bin Entrapment http: //www. agriview. com/news/crop/bushels-of-risk-involved-withflowing-grain/article_da 7612 f 4 -2 a 99 -11 e 2 -a 78 b-0019 bb 2963 f 4. html

Objectives • Measure the pressure on the chest and back of an entrapment victim • Investigate differences in grain type and depth

Treatments • Four grain depths • • Top of shoulders Top of head One foot below surface Two feet below surface • Four grain types • • Soybeans Wheat Corn Canola

Tekscan Pressure Measurement http: //www. tekscan. com/products

Tekscan CONFORMat System • 18. 5 in x 18. 5 in sensing area with 1, 024 “sensels” • Sensels are force sensitive variable resistors • Pressure measurement at each sensel location • Pressure map

Test Procedure • 1. 83 m (6 ft) hopper bin • Load grain to desired depth, record pressure, unload grain • Repeat for each replication and depth

Sensor Output

Mean Pressure

Mean Pressure

Calibration Challenges • Required prior to testing for each grain • Equilibration with vacuum bladder • Calibration load applied with Instron • Two point power law calibration curve in CONFORMat software

Calibration Challenges • Mistake in entering calibration load • Significant deviation in results • Calibration is critical to data quality!

Future Work • Complete testing with corn and canola • Model behavior with PFC 3 D • Investigate physiological response to measured pressures Funding for this research was supported by the Southwest Center for Agricultural Health, Injury Prevention and Education through Cooperative Agreement #U 54 -OH 7541 from CDC/NIOSH

Questions?