Geo-referenced digital imaging and ultrasonic altitude sensing for agricultural aircraft - pilot controls, instrumentation, and system evaluations

摘要

Instrumentation are being developed for two separate remote sensing systems used on agricultural aircraft. One project was initiated to develop an imaging system for site-specific crop management. Instrumentation, pilot controls, and a digital video-based remote sensing system with geo-referencing have been adapted for convenient use by the pilot and to permit efficient image post-processing. Weeds were successfully discriminated and distinguished from cotton using classification methods in the ENVI 3.4 image analysis system. The parallelepiped and Mahalanobis distance methods allowed good discrimination of weeds and cotton with optimized distance parameters. For a second remote sensing application, preliminary data are presented for an ultrasonicaltitude sensor, to be used in aerial spray application research. Preliminary data indicated a strong, repeatable signal when flying over a road surface but a questionable signal over bare soil and low crop canopy. Further testing of this method will beaccomplished using a more flexible sonar-based system that allows electronic control of system parameters.