Omnidirectional vision system for controllng mobile machines

• US 4,670,648 A
• Filed: 03/06/1985
• Issued: 06/02/1987
• Est. Priority Date: 03/06/1985
• Status: Expired due to Term

• Current Assignee: University of Cincinnati
• Original Assignee: University of Cincinnati
• Inventors: Ehtashami, Mohammad, Hall, Ernest L.
• Primary Examiner(s): NOT, DEFINED
• Assistant Examiner(s): Wieland, Charles
• Application Number:
  US06/708,671
• Time in Patent Office: 818 Days
• Field of Search: 350/441, 244/3.16, 244/3.17, 356/1, 356/4, 250/216, 358/87
• US Class Current: 250/216
• CPC Class Codes: G01S 5/16 using electromagnetic waves other than radio waves
• CPC Class Codes: G05D 1/0246 using a video camera in combination with image processing means
• CPC Class Codes: G05D 1/027 comprising intertial navigation means, e.g. azimuth detector inertial navigation G01C21/16; inertial navigation combined with non-inertial navigation instruments G01C21/165

Abstract

An optical sensor apparatus receives visible light and converts that light to electrical signals for use by a control system. Visible light enters the apparatus through a hemispherical "fisheye" lens which provides a 360° field of view in azimuth and a 180° field of view in elevation. The light exiting the fisheye lens is projected through a shutter mechanism onto a receptor of a camera. The lens, shutter mechanism, camera and a level dector are mounted on a gimbal mounting to maintain a vertical orientation of the lens and camera. When the optical sensor apparatus is called upon by the control system to provide visual information, the shutter mechanism is energized to open when the lens and camera next become vertical. Image processing is then performed to determine the position of the optical sensor apparatus relative to known landmarks in the operating environment.

Claims

1. An optical imaging assembly for use with a mobile machine guidance control system or the like comprising:

a wide-angle lens having an optical axis and a substantially 360°

field of view in azimuth for projecting images received from the surroundings;

a means for producing electrical signals representative of said images projected by said lens;

a pivotable gimbal for mounting said lens and signal producing means, said gimbal providing pivoting of said lens and signal producing means around two perpendicular pivot axes to thereby maintain said optical axis of said lens in vertical orientation in use;

sensor means for detecting the orientation of said lens and signal producing means; and

means responsive to said orientation detecting means for selectively sampling said representative electrical signals only when said optical axis is oriented vertically.

2. The imaging assembly according to claim 1 wherein said signal producing means comprises an electronic camera.

3. The optical imaging assmebly according to claim 1 wherein said wide angle lens comprises a hemispherical fisheye lens having a substantially 360°

field of view in azimuth and a substantially 180°

field of view in elevation.

4. The imaging assembly according to claim 3 wherein said signal producing means comprises an electronic camera.

5. An optical imaging assembly for use with a mobile machine guidance control system or the like comprising:

a wide-angle lens having a substantially 360°

field of view in azimuth for projecting images received from the surroundings;

a means for producing electrical signals representative of said images projected by said lens;

a pivotable gimbal for mounting said lens and signal producing means;

sensor means for detecting the orientation of said lens and signal producing means; and

means responsive to said orientation detecting means for selectively sampling said representative electrical signals, said selective sampling means comprising a shutter mechanism responsive to said orinetation detecting means and positioned between said lens and said signal producing means for allowing said projected images to reach said signal producing means only when predetermined conditions are satisfied.

6. The imaging assembly according to claim 5 wherein said signal producing means comprises an electronic camera.

7. An optical imaging assembly for use with a mobile machine guidance control system or the like comprising:

a wide-angle hemispherical fisheye lens having a substantially 360°

field of view in azimuth and a substantially 180°

field of view in elevation for projecting images received from the surroundings;

a means for producing electrical signals representative of said images projected by said lens;

a pivotable gimbal for mounting said lens and signal producing means;

sensor means for detecting the orientation of said lens and signal producing means; and

means responsive to said orientation detecting means for selectively sampling said representative electrical signals, said selective sampling means comprising a shutter mechanism responsive to said orinetation detecting means and positioned between said lens and said signal producing means for allowing said projected images to reach said signal producing means only when predetermined conditions are satisfied.

8. The imaging assembly according to claim 7 wherein said signal producing means comprises an electronic camera.