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EP-4737982-A1 - SUSPENDED CAMERA COVER GLASS FOR ULTRASONIC CLEANING

EP4737982A1EP 4737982 A1EP4737982 A1EP 4737982A1EP-4737982-A1

Abstract

A sensor assembly that includes a housing that defines a cavity therein, a lens disposed in the cavity, an image sensor disposed in the cavity, a cover glass movably coupled to the housing, and a piezoelectric device coupled to the cover glass. The image sensor is aligned with the lens along an optical axis of the sensor assembly. The cover glass is positioned outward from the lens and the image sensor such that the image sensor is configured to capture images within a field of view of the lens through the cover glass. The piezoelectric device is configured to oscillate the cover glass to clean one or more surfaces of the cover glass.

Inventors

  • GRODAHL, JASON
  • BONEFAS, Zachary T.
  • ELLERBACH, JOSEPH J.
  • BROWN, JASON

Assignees

  • Deere & Company

Dates

Publication Date
20260506
Application Date
20251007

Claims (15)

  1. A sensor assembly (208), comprising: a housing (222) that defines a cavity (224) therein; a lens (220) disposed in the cavity (224); an image sensor (242) disposed in the cavity (224) and aligned with the lens (220) along an optical axis (240) of the sensor assembly (208); a cover glass (226) movably coupled to the housing (222) and positioned outward from the lens (220) and the image sensor (242) such that the image sensor (242) is configured to capture images within a field of view of the lens (220) through the cover glass (226); and a piezoelectric device (234) coupled to the cover glass (226) and configured to oscillate the cover glass (226) to clean one or more surfaces of the cover glass (226).
  2. The sensor assembly (208) of claim 1, wherein the cover glass (226) is movably coupled to the housing (222) in a suspended state such that the cover glass (226) is free of direct contact with the housing (222).
  3. The sensor assembly (208) of claim 2, wherein the cover glass (226) is movably coupled to the housing (222, 322) by a cover glass (226) seal disposed therebetween.
  4. The sensor assembly (208) of claim 1, wherein the cover glass (226) includes a front surface (264) that is configured to be exposed to environmental elements and an opposing rear surface (266) that faces the lens (220).
  5. The sensor assembly (208) of claim 4, wherein the piezoelectric device (234) is coupled to the opposing rear surface (266) of the cover glass (226) and laterally positioned between the housing (222) and the optical axis (240) with respect to the optical axis (240).
  6. The sensor assembly (208) of claim 1, wherein the piezoelectric device (234) is configured to vibrate the cover glass (226).
  7. The sensor assembly (208) of claim 6, wherein at least a portion of the piezoelectric device (234) is configured to expand and contract in response to application of an electrical voltage to the piezoelectric device (234) to vibrate the cover glass (226) at a frequency of about 20 kHz to about 400 kHz.
  8. The sensor assembly (208) of claim 1, wherein the housing (222) includes: a main housing (254), wherein the cover glass (226) is movably coupled to the main housing (254); a front housing (256) coupled to the main housing (254) and positioned outward from the cover glass (226); and a rear housing (258) coupled to the main housing (254,) and positioned inward from the main housing (254) and the front housing (256).
  9. The sensor assembly (208) of claim 8, wherein the front housing (256) extends towards the optical axis (240) beyond a peripheral edge (228) of the cover glass (226) such that the peripheral edge (228) of the cover glass (226) is obstructed from view from a viewpoint external to the sensor assembly (208).
  10. The sensor assembly (208) of claim 8, wherein a front seal (260) is disposed between the front housing (256) and the main housing (254), and a rear seal is disposed between the rear housing (258) and the main housing (254).
  11. The sensor assembly (208) of claim 1, wherein the piezoelectric device (234) is configured to be electrically connected to a control module (238), and wherein the control module (238) is configured to operate the piezoelectric device (234) to oscillate the cover glass (226).
  12. A sensor assembly (208) for an agriculture machine, comprising: a housing (222); a lens (220) disposed in the housing (222) along an optical axis (240) of the sensor assembly (208); an image sensor (242) disposed in the housing (222) and positioned inward from the lens (220) along the optical axis (240); a cover glass (226) movably coupled to the housing (222) by a cover glass (226) seal, wherein the image sensor (242) is configured to capture images within a field of view of the lens (220) through the cover glass (226); and a piezoelectric device (234) coupled to a surface of the cover glass (226) and configured to vibrate the cover glass (226,) to clean the cover glass (226), wherein the cover glass (226) seal is configured to maintain a seal between the cover glass (226) and the housing (222) when the cover glass (226) is vibrated by the piezoelectric device (234).
  13. The sensor assembly (208) of claim 12, wherein the cover glass (226) seal is made of a flexible material that allows for vibration of the cover glass (226) while still maintaining the seal between the cover glass (226) and the housing (222).
  14. The sensor assembly (208) of claim 12, wherein the piezoelectric device (234) is configured to vibrate at different frequencies to remove at least one of debris, moisture, frost, or ice from the cover glass (226).
  15. The sensor assembly (208) of claim 14, wherein the piezoelectric device (234) is configured to selectively vibrate at ultrasonic frequencies.

Description

This disclosure relates to a sensor system, and more particularly, to ultrasonic cleaning of cover glass of a sensor system. BACKGROUND Sensor systems may be used in various agriculture, construction, automotive, forestry, mining, and maintenance operations to capture images for analysis of different parameters to determine overall performance of the various operations. Such sensor systems may be connected to machinery to capture images during operation of the machinery and analyze the captured images to enhance performance of the machinery. SUMMARY In one aspect of the present disclosure, a sensor assembly is disclosed. The sensor assembly includes a housing that defines a cavity therein, a lens disposed in the cavity, an image sensor disposed in the cavity, a cover glass movably coupled to the housing, and a piezoelectric device coupled to the cover glass. The image sensor is aligned with the lens along an optical axis of the sensor assembly. The cover glass is positioned outward from the lens and the image sensor such that the image sensor is configured to capture images within a field of view of the lens through the cover glass. The piezoelectric device is configured to oscillate the cover glass to clean one or more surfaces of the cover glass. In some implementations, the cover glass may be movably coupled to the housing in a suspended state such that the cover glass is free of direct contact with the housing. The cover glass may be movably coupled to the housing by a cover glass seal disposed therebetween. In some implementations, the cover glass may include a front surface that is configured to be exposed to environmental elements and an opposing rear surface that faces the lens. The piezoelectric device may be coupled to the opposing rear surface of the cover glass and laterally positioned between the housing and the optical axis with respect to the optical axis. In some implementations, the piezoelectric device may be configured to vibrate the cover glass. At least a portion of the piezoelectric device may be configured to expand and contract in response to application of an electrical voltage to the piezoelectric device to vibrate the cover glass at a frequency of about 20 kHz to about 400 kHz. In some implementations, the housing may include a main housing, a front housing coupled to the main housing and positioned outward from the cover glass, and a rear housing coupled to the main housing and positioned inward from the main housing and the front housing. The cover glass may be movably coupled to the main housing. The front housing may extend towards the optical axis beyond a peripheral edge of the cover glass such that the peripheral edge of the cover glass is obstructed from view from a viewpoint external to the sensor assembly. A front seal may be disposed between the front housing and the main housing. A rear seal may be disposed between the rear housing and the main housing. In some implementations, the piezoelectric device may be configured to be electrically connected to a control module. The control module may be configured to operate the piezoelectric device to oscillate the cover glass. In another aspect of the present disclosure, a sensor assembly for an agriculture machine is disclosed. The sensor assembly includes a housing, a lens disposed in the housing along an optical axis of the sensor assembly, an image sensor disposed in the housing and positioned inward from the lens along the optical axis, a cover glass movably coupled to the housing by a cover glass seal, and a piezoelectric device coupled to a surface of the cover glass. The image sensor is configured to capture images within a field of view of the lens through the cover glass. The piezoelectric device is configured to vibrate the cover glass to clean the cover glass. The cover glass seal is configured to maintain a seal between the cover glass and the housing when the cover glass is vibrated by the piezoelectric device. In some implementations, the cover glass seal may be made of a flexible material that allows for vibration of the cover glass while still maintaining the seal between the cover glass and the housing. In some implementations, the piezoelectric device may be configured to vibrate at different frequencies to remove at least one of debris, moisture, frost, or ice from the cover glass. The piezoelectric device may be configured to selectively vibrate at ultrasonic frequencies. In some implementations, the piezoelectric device may be configured to selectively vibrate at different frequencies based upon detection of a particular contaminant disposed on one or more surfaces of the cover glass. In another aspect of the present disclosure, a sensor assembly is disclosed. The sensor assembly includes a housing that defines a cavity therein, a sensor disposed in the cavity, a cover glass coupled to the main housing by a cover glass seal, and a piezoelectric device coupled to the cover glass and configured to vibrate