Device and method for detecting objects passing through a passageway

Patent metadata

Field	Value
Publication number	US-11470766-B2
Application number	US-202016945495-A
Country	US
Kind code	B2
Filing date	Jul 31, 2020
Priority date	Oct 31, 2019
Publication date	Oct 18, 2022
Grant date	Oct 18, 2022

Abstract

An object detection system compensates for variations in transmission characteristics within an object passageway caused by, for example, dust or dirt. An object detection device includes a plurality of electromagnetic radiation emitters and detectors arranged in rows on opposite sides of a passageway. First lenses focus radiation from the emitters into a semi-columnated beams of radiation that together create a plane of semi-columnated electromagnetic radiation that spans substantially across a width of the passageway. Second lenses focus the received electromagnetic radiation onto corresponding ones of the plurality of radiation detectors. A controller receives a radiation intensity signal from the detectors, determines that its value is outside of a predetermined range, and adjusts an amount of electrical power supplied to the plurality of radiation emitters so that the value of the radiation intensity signal changes to become within the predetermined range.

First claim

What is claimed is:

1. An object detection device to detect moving objects passing through a passageway conduit, the object detection device comprising:
a plurality of electromagnetic radiation (radiation) emitters arranged in a row;
a plurality of first lenses arranged in a row on a first sidewall of the passageway conduit, wherein a number of the plurality of first lenses is commensurate in number to a number of the plurality of radiation emitters, wherein each one of the plurality of first lenses is configured to focus electromagnetic radiation emitted from a corresponding one of the plurality of radiation emitters into a semi-columnated beam of electromagnetic radiation, and wherein the plurality of first lenses together are configured to create a plane of semi-columnated electromagnetic radiation that spans substantially across a width of the passageway conduit;
a plurality of radiation detectors configured to receive electromagnetic radiation and output an electrical signal corresponding to an intensity of the received electromagnetic radiation; and
a plurality of second lenses arranged in a row on a second sidewall of the passageway conduit opposite to the first sidewall and arranged to receive the plane of semi-columnated electromagnetic radiation, wherein a number of the plurality of second lenses is commensurate in number to a number of the plurality of radiation detectors, wherein each one of the plurality of second lenses is configured to focus a received portion of the plane of semi-columnated electromagnetic radiation onto a corresponding one of the plurality of radiation detectors,
wherein the plurality of first lenses are configured such that an edge of a first semi-columnated beam of electromagnetic radiation focused by a first lens of the plurality of first lenses overlaps with an edge of a second semi-columnated beam of electromagnetic radiation focused by a second lens of the plurality of first lenses that is adjacent to the first semi-columnated beam of electromagnetic radiation; and
wherein the plurality of second lenses are configured such that a first lens of the plurality of second lenses associated with the first semi-columnated beam of electromagnetic radiation also receives a portion of the second semi-columnated beam of electromagnetic radiation and focuses the portion of the second semi-columnated beam of electromagnetic radiation onto a first radiation detector of the plurality of radiation detectors corresponding to the first lens of the plurality of second lenses.

2. The object detection device of claim 1 , further comprising:
a diffusion layer disposed on a surface of the plurality of first lenses opposite from the plurality of emitters, the diffusion layer configured to diffuse the electromagnetic radiation exiting the plurality of first lenses to aid in generating the plane of semi-columnated electromagnetic radiation.

3. The object detection device of claim 1 , wherein a number of the plurality of radiation emitters equals a number of the plurality of radiation detectors.

4. The object detection device of claim 1 , wherein the radiation emitters are infrared (IR) light emitting diodes (LEDs) and wherein the radiation detectors are IR photodiodes.

5. The object detection device of claim 1 , wherein the plurality of semi-columnated beams of electromagnetic radiation from the plurality of first lenses each comprise a radiation channel between a corresponding radiation emitter and a corresponding radiation detector, and wherein the object detection device further comprises:
a controller coupled to a memory device, the controller configured to:
sample a radiation intensity signal corresponding to the intensity of the electromagnetic radiation of each radiation channel as received by the plurality of radiation detectors, wherein each radiation channel is time-varying and can vary from sample to sample; and
store in the memory device the samples of each of the sampled radiation intensity signals.

6. The object detection device of claim 1 , further comprising:
a controller configured to:
receive a radiation intensity signal corresponding to the intensity of the electromagnetic radiation received by the plurality of radiation detectors;
determine that a value of the radiation intensity signal is outside of a predetermined range; and
in response to the determining that the value of the radiation intensity signal is outside of the predetermined range, adjust an amount of electrical power supplied to the plurality of radiation emitters to at least one of increase or decrease an intensity of electromagnetic radiation emitted by the plurality of radiation emitters so that the value of the radiation intensity signal changes to become within the predetermined range.

7. The object detection device of claim 6 , wherein the predetermined range corresponds to an optimal sensing range of at least one of the plurality of radiation detectors or an input of the controller that receives the radiation intensity signal.

8. The object detection device of claim 6 , further comprising:
a temperature sensor configured to sense a temperature associated with the plurality of radiation emitters and output a radiation emitter temperature signal;
wherein the controller is further configured to:
receive the radiation emitter temperature signal; and
adjust an amount of electrical power supplied to the plurality of radiation emitters to at least one of increase or decrease an intensity of electromagnetic radiation emitted by the plurality of radiation emitters to account for electromagnetic radiation efficiency changes caused by temperature variations of the plurality of radiation emitters.

9. The object detection device of claim 6 , wherein the controller is further configured to:
determine that no moving objects are passing through the plane of semi-columnated electromagnetic radiation; and
determine that the value of the radiation intensity signal is outside of the predetermined range in response to determining that no moving objects are passing through the plane of semi-columnated electromagnetic radiation.

10. The object detection device of claim 1 , further comprising:
a controller configured to:
control operation of a first individual radiation emitter of the plurality of radiation emitters to emit electromagnetic radiation and control operation of a remainder of the plurality of radiation emitters to not emit electromagnetic radiation;
receive a radiation intensity signal corresponding to an intensity of radiation received by at least a first individual radiation detector of the plurality of radiation detectors corresponding to the first individual radiation emitter;
determine that a value of the radiation intensity signal is outside of a predetermined range; and
in response to the determining that the value of the radiation intensity signal is outside of the predetermined range, adjust an amount of electrical power supplied to the first radiation emitter to at least one of increase or decrease an intensity of electromagnetic radiation emitted by the first radiation emitter so that the value of the radiation intensity signal changes to become within the predetermined range.

11. The object detection device of claim 10 , wherein the controller is further configured to:
control operation of the remainder of the plurality of radiation emitters to emit electromagnetic radiation one at a time during different time segments;
receive radiation intensity signals corresponding to intensities of electromagnetic radiation received by a remainder of the plurality of radiation detectors, each individual radiation detector of the remainder of the plurality of radiation detec

Assignees

• Deere & Co

Inventors

• King Ryan J
• Cowles Kevin P
• Jelinek Jason A
• Lindseth Waylon R
• Zhang Haifeng
• Perkinson Caleb A
• Puhalla Jeffrey S

Classifications

• H05B45/12

  using optical feedback · CPC title

• G01N2015/1486

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• A01C7/105 Primary

  Seed sensors · CPC title

• G01N15/1429

  Signal processing · CPC title

• G01N2015/1488

  Methods for deciding · CPC title