Topographic Mapping Through Measurement of Vehicle Attitude and Elevation
A self-propelled agricultural sprayer was equipped with four RTK DGPS receivers and an inertial measurement unit (IMU) to measure vehicle attitude and field elevation as the vehicle was driven across a field. Data were collected in a stop-and-go fashion at 3.05 m (10 ft) intervals, as well as in a continuous fashion at three different speed levels on a 2.3 ha field area with varying topography. Pitch and roll offset angles were estimated to within 95% confidence intervals that ranged from 0.01° to 0.10°. Using ordinary kriging, digital elevation models (DEMs) were interpolated using only elevation measurements, as well as a combination of elevation and vehicle attitude measurements. The resulting DEMs were compared with each other to evaluate the effect of including attitude measurement on DEM accuracy. At the widest measurement swath width, the DEMs generated with attitude measurements had RMSE values of 10 to 11 cm, which was significantly lower than the RMSE of 15 cm associated with the DEMs generated without attitude measurements. Vehicle speed affected DEM error, but no discernable trends were detected. These results provide evidence supporting the feasibility of using vehicle-based measurements collected during typical field operation for accurate DEM development.
This article is from Transactions of the ASAE, 47, no. 5 (2004): 1841–1849.