Unwanted plant removal system
Embodiments include an apparatus and methods for removing unwanted plants or weeds from an area such as an agricultural plot or lawn. The apparatus includes a three-dimensional imager configured to capture plant images and locate plants; an image processor configured to distinguish between wanted and unwanted plants based upon the captured plant images; at least one laser device configured to emit a laser beam having power sufficient to damage the unwanted plants; a laser beam controller configured to direct at least one laser beam toward the unwanted plant; and a chassis configured to support the three-dimensional imager, the laser device, and the laser beam controller. The chassis is configured to be moved across the area.
1. An apparatus comprising:
a three-dimensional imager configured to capture plant images and locate plants, the three dimensional imager comprising a multispectral imager having at least a first channel associated with a first spectral range and a second channel associated with a second spectral range;
an image processor configured to:
compare information obtained from the first channel to information obtained from the second channel, and
distinguish between a wanted plant and an unwanted plant based on the captured plant images and the comparison;
at least one laser device configured to emit a laser beam having power sufficient to damage the unwanted plant;
a laser beam controller configured to direct at least one laser beam toward the unwanted plant; and
a chassis configured to support the three-dimensional imager, the laser device, and the laser beam controller, and configured to be moved across an area.
2. An apparatus according to claim 1 , wherein the three-dimensional imager uses triangulation to locate plants.
3. An apparatus according to claim 2 , wherein the three-dimensional imager comprises a stereo camera system that includes at least two cameras.
4. An apparatus according to claim 2 , wherein the three-dimensional imager comprises a scanning system that includes a single or a multiple beam laser scanner and a single camera.
5. An apparatus according to claim 2 , wherein the three-dimensional imager comprises a scanning system that includes a single or multiple beam scanner and a stereo camera, and wherein the stereo camera includes two cameras.
6. An apparatus according to claim 2 , wherein the three-dimensional imager comprises a three-dimensional structured illuminator and at least one camera.
7. An apparatus according to claim 1 , wherein the three-dimensional imager comprises a time-of-flight measurement system.
8. An apparatus according to claim 7 , wherein the time-of-flight measurement system is comprised of a photonic mixer device sensor and a modulated light source.
9. An apparatus according to claim 7 , wherein the three-dimensional imager comprises an imaging lens and a two-dimensional sensor array.
10. An apparatus according to claim 7 , wherein the three-dimensional imager comprises a light source with one or more scanning beams, collection optics, and one or more detectors.
11. An apparatus according to claim 1 , wherein the laser device comprises an array of semiconductor lasers.
12. An apparatus according to claim 1 , wherein the laser device comprises at least one semiconductor laser configured to emit a laser beam having a wavelength of from about 430 nm to about 475 nm or from about 650 nm to about 675 nm.
13. An apparatus according to claim 1 , wherein the laser beam controller comprises at least one galvo mirror.
14. An apparatus according to claim 13 , wherein the at least one galvo mirror comprises a two-axis MEMS galvo mirror.
15. An apparatus according to claim 1 , wherein the three-dimensional imager, the laser device, and the laser beam controller supported by the chassis can sense and adjust in all three-dimensions.
16. A lawn weeding system comprising:
a lawn mower comprising cutting means; and
an apparatus according to claim 1 , wherein the chassis is mechanically coupled to the lawn mower.
17. A lawn weeding system according to claim 16 , wherein the cutting means are mechanical or electrooptical.
18. A lawn weeding system according to claim 16 , wherein the lawn mower generates power to energize at least one of the three-dimensional imager, the image processor, the at least one laser device, and the laser beam controller.
19. An apparatus according to claim 1 , wherein the apparatus is a lawn mower and the laser beam is configured to cut vegetation and to damage the unwanted plant.
20. A method of removing unwanted plants comprising:
capturing plant images using a three-dimensional imager the three dimensional imager comprising a multispectral imager having at least a first channel associated with a first spectral range and a second channel associated with a second spectral range;
comparing information obtained from the first channel to information obtained from and the second channel;
distinguishing between a wanted plant and an unwanted plant based on the plant images and the comparison;
directing a laser beam from at least one laser device towards the unwanted plant; and
damaging the unwanted plant with the laser beam.
21. A method of removing unwanted plants according to claim 20 , further comprising providing a laser beam controller configured to direct at least one laser beam towards the unwanted plant.
22. A method of removing unwanted plants according to claim 21 , further comprising mounting the three-dimensional imager, the at least one laser device and the laser beam controller on a chassis.
23. A method of removing unwanted plants according to claim 22 , further comprising moving the chassis across an agricultural field or lawn.