Skip to main content
Article
Utilizing Repeated GPS Surveys from Field Operations for Development of Agricultural Field DEMs
Transactions of the ASABE
  • Samsuzana Abd Aziz, Iowa State University
  • Brian L. Steward, Iowa State University
  • Lie Tang, Iowa State University
  • Manoj Karkee, Iowa State University
Document Type
Article
Publication Version
Published Version
Publication Date
1-1-2009
Abstract

Topographic data collected using RTK-DGPS-equipped farm vehicles during field operations could addadditional benefits to the original capital investment in the equipment through the development of high-accuracy field DEMs. Repeated surveys of elevation data from field operations may improve DEM accuracy over time. However, minimizing the amount of data to be processed and stored is also an important goal for practical implementation. A method was developed to utilize repeated GPS surveys acquired during field operations for generating field-level DEMs. Elevation measurement error was corrected through a continuity analysis. Fuzzy logic (FL) and weighted averaging (WA) methods were used to combine new surveys with past elevation estimates without requiring storage and reprocessing of past survey data. After 20 surveys were included, the DEM of the study area generated with FL and WA methods had an average root mean squared error (RMSE) of 0.08 m, which was substantially lower than the RMSE of 0.16 m associated with the DEM developed by averaging all data points in each grid. With minimum control of errors in elevation measurements, the effect of these errors can be reduced with appropriate data processing, including continuity analysis, fuzzy logic, and weighted averaging. Two years of GPS surveys of elevation data from field operations could reduce elevation error by 50% in field DEMs.

Comments

This article is from Transactions of the ASABE, 52, no. 4 (2009): 1057–1067.

Access
Open
Copyright Owner
American Society of Agricultural and Biological Engineers
Language
en
File Format
application/pdf
Citation Information
Samsuzana Abd Aziz, Brian L. Steward, Lie Tang and Manoj Karkee. "Utilizing Repeated GPS Surveys from Field Operations for Development of Agricultural Field DEMs" Transactions of the ASABE Vol. 52 Iss. 4 (2009) p. 1057 - 1067
Available at: http://works.bepress.com/lie_tang/8/