Patent · US Expired

Detecting plants in a field by detecting a change in slope in a reflectance characteristic

US5789741A · kind A · utility

159Cited by
50References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 31, 1996
Grant dateAug 4, 1998
Priority date
Expiry dateOct 31, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01J3/50
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

An agricultural implement (for example, a spray device) differentiates living plants growing in a field from background materials (such as soil) by detecting a change in slope of a reflectance characteristic of objects in a field of view. By using a change in slope of the reflectance characteristic, a small percentage of living plant material in the field of view can be detected and the agricultural implement need not be calibrated to a particular background material. In some embodiments, if the change in slope is determined to exceed a predetermined threshold amount, then it is determined that a weed likely exists in the field of view and a solenoid-operated spray valve is opened at the appropriate time to spray the entire area (including the weed) that was in the field of view with herbicide.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.