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.
Abstract:
Weeds growing around the bases of the stalks of cotton plants growing in a row in a cotton field are sprayed with herbicide without spraying the cotton stalks or wasting herbicide on bare ground. The cotton plants are adequately mature that their stalks exhibit a significantly different spectral reflectance characteristic than the weeds typically growing amid the cotton. The cotton plants are adequately tall that the majority of the leaves of the cotton plants are disposed outside the area which can be sprayed using an electronically-controlled valve and nozzle. Light is transmitted toward an object (a cotton stalk, a weed, or soil) in the row and the reflected light is analyzed. If the object has a spectral characteristic of a growing weed, then the valve is activated and the object is sprayed with herbicide. If the object does not have the spectral characteristic of a growing weed (such as the spectral characteristic of a woody cotton stalk or of soil), then the valve is not activated and the object is not sprayed with herbicide.
Abstract:
An optical proximity sensor generates information indicative of a distance to an object in a field and in some embodiments also generates information indicative of a spectral reflectance characteristic of the object. The information indicative of the spectral reflectance characteristic can be used to determine whether the object in the field is a living plant or another object such as soil. Light emitted from the optical sensor for reflection off the object is modulated so that reflected light from the optical sensor can be discriminated from reflected ambient sunlight. The optical sensor is scanned over the field to map objects in the field and/or to determine the location of rows of crop plants. A sensor in accordance with the present invention has many uses in agriculture including spraying, cultivation and vehicle guidance.
Abstract:
An agricultural implement for spraying herbicide on weeds in a field without spraying herbicide on bare soil includes a photodetector circuit. The photodetector circuit includes a photodetector and an active filter. The photodetector is not AC coupled in parallel with an inductor/capacitor resonant circuit which tunes the active filter. As a result, changes in photodetector capacitance due to changes in ambient lighting conditions are not impressed across the resonant inductor/capacitor circuit and therefore do not adversely change the frequency and phase characteristics of the photodetector circuit.
Abstract:
Weeds (100) growing around the bases of the stalks of cotton plant (101) growing in a row (105 and 105A) in a cotton field are sprayed with herbicide without spraying the cotton stalks (101) or wasting herbicide on bare ground (107). The cotton plants are adequately mature that their stalks exhibit a significantly different spectral reflectance characteristic than the weeds typically growing amid the cotton. The cotton plants are adequately tall that the majority of the leaves of the cotton plants are disposed outside the area which can be sprayed using an electronically-controlled valve and nozzle (103). Light is transmitted toward an object (a cotton stalk, a weed, or soil) in the row and the reflected light is analyzed. If the object has a spectral characteristic of a growing weed, then the valve is activated and the object is sprayed with herbicide. If the object does not have the spectral characteristic of a growing weed, then the valve is not activated and the object is not sprayed with herbicide.
Abstract:
An optical proximity sensor (1) generates information indicative of a distance (D1) to an object (14A) in a field and in some embodiments also generates information indicative of a spectral reflectance characteristics of the object (14A). The information indicative of the spectral reflectance characteristic can be used to determine whether the object (14A) in the field is a living plant (14A) or another object such as soil (10). Light emitted from the optical sensor (1) for reflection off the object (14A) is modulated so that reflected light from the optical sensor can be discriminated from reflected ambient sunlight. The optical sensor (1) is scanned over the field to map objects in the field and/or to determine the location of rows of crop plants. A sensor in accordance with the present invention has many uses in agriculture including spraying, cultivation and vehicle guidance.
Abstract:
Weeds (100) growing around the bases of the stalks of cotton plant (101) growing in a row (105 and 105A) in a cotton field are sprayed with herbicide without spraying the cotton stalks (101) or wasting herbicide on bare ground (107). The cotton plants are adequately mature that their stalks exhibit a significantly different spectral reflectance characteristic than the weeds typically growing amid the cotton. The cotton plants are adequately tall that the majority of the leaves of the cotton plants are disposed outside the area which can be sprayed using an electronically-controlled valve and nozzle (103). Light is transmitted toward an object (a cotton stalk, a weed, or soil) in the row and the reflected light is analyzed. If the object has a spectral characteristic of a growing weed, then the valve is activated and the object is sprayed with herbicide. If the object does not have the spectral characteristic of a growing weed, then the valve is not activated and the object is not sprayed with herbicide.
Abstract:
An optical proximity sensor (1) generates information indicative of a distance (DI) to an object (14A) in a field and in some embod- iments also generates information indicative of a spectral reflectance characteristics of the object (14A). The information indicative of the spectral reflectance characteristic can be used to determine whether the object (14A) in the field is a living plant (14A) or another object such as soil (10). Light emitted from the optical sensor (1) for reflection off the object (14A) is modulated so that reflected light from the optical sensor can be discriminated from reflected ambient sunlight. The opti- cal sensor (1) is scanned over the field to map objects in the field and/or to determine the location of rows of crop plants. A sensor in accor- dance with the present invention has many uses in agriculture including spraying, cultivation and vehicle guidance.
Abstract:
Weeds growing around the bases of the stalks of cotton plants growing in a row in a cotton field are sprayed with herbicide without spraying the cotton stalks or wasting herbicide on bare ground. The cotton plants are adequately mature that their stalks exhibit a significantly different spectral reflectance characteristic than the weeds typically growing amid the cotton. The cotton plants are adequately tall that the majority of the leaves of the cotton plants are disposed outside the area which can be sprayed using an electronically-controlled valve and nozzle. Light is transmitted toward an object (a cotton stalk, a weed, or soil) in the row and the reflected light is analyzed. If the object has a spectral characteristic of a growing weed, then the valve is activated and the object is sprayed with herbicide. If the object does not have the spectral characteristic of a growing weed (such as the spectral characteristic of a woody cotton stalk or of soil), then the valve is not activated and the object is not sprayed with herbicide.