ANGLED AXIS MACHINE VISION SYSTEM AND METHOD

• US 20060012673A1
• Filed: 07/16/2004
• Published: 01/19/2006
• Est. Priority Date: 07/16/2004
• Status: Active Grant

• Current Assignee: Vision Robotics Corporation
• Original Assignee: Vision Robotics Corporation
• Inventors: Wallach, Bret, Koselka, Harvey
• Granted Patent: US 7,196,719 B2
• Time in Patent Office: Days
• US Class Current: 348/42
• CPC Class Codes: G06T 2207/30252 Vehicle exterior; Vicinity of vehicle
• CPC Class Codes: G06T 7/85 Stereo camera calibration
• CPC Class Codes: H04N 13/239 using two 2D image sensors having a relative position equal to or related to the interocular distance H04N13/243 takes precedence
• CPC Class Codes: H04N 2013/0081 Depth or disparity estimation from stereoscopic image signals

Abstract

Embodiments of the invention comprise an angled axis machine vision system having a camera system angled with respect to an axis of the coordinate system of the environment. This configuration has all of the advantages of the horizontal alignment while eliminating the inherent problem of utilizing horizontal and vertical lines in an environment for distance calculations when the horizontal and vertical lines are parallel or close to parallel to an axis lying between camera centers of the camera system. With the camera centers angled about the roll axis, horizontal and vertical lines in the environment appear as angled lines in images taken from the cameras enabling more accurate distance calculations. With the camera centers angled downward about the pitch axis objects that are near are more readily observed. With angled axis rotation it is still possible for lines in the environment to be parallel to the axis defined between the camera centers, but these instances are rarer than horizontal or vertical lines in real world environments. Embodiments of the invention may comprise a camera mount that is rotatably mounted to a support wherein two sets of pictures from each of the cameras may either be utilized. In one embodiment the two sets are compared for the number of lines which are parallel to the axis of the camera centers and the set of pictures with the least lines parallel is used for distance calculations. In another embodiment, the two sets are utilized to correlate the distances derived from each set of pictures.

Claims

1-33. -33. (canceled)

34. A system for calculating distances to objects within three-dimensional space in an environment comprising horizontal and vertical lines using an angled axis machine vision system comprising:

a first camera;

a second camera mounted coplanar to said first camera wherein said first camera and said second camera comprise collinear horizontal center lines

a camera mount coupled with said first camera and said second camera wherein said camera mount is rotated in a first axial angle between 0 and 90 degrees about a roll axis; and

,

a computer coupled with said first camera and said second camera and configured to calculate a distance using a first picture obtained from said first camera and a second picture obtained from said second camera to a feature found along an epipolar line parallel to said collinear horizontal center lines.

35. The system of claim 34 wherein said first axial angle is substantially 45 degrees.

36. The system of claim 34 wherein said first axial angle is substantially 37 degrees.

37. The system of claim 34 wherein said first axial angle is substantially 29 degrees.

38. The system of claim 34 wherein said camera mount is rotated in a second axial angle between 0 and 90 degrees about a pitch axis orthogonal to said roll axis.

39. A method for calculating distances to objects within three-dimensional space in an environment comprising horizontal and vertical lines using an angled axis machine vision system comprising:

attaching a first camera and a second camera to a camera mount;

rotating said camera mount in a first axial angle between 0 and 90 degrees about a first axis;

obtaining a first picture from said first camera;

obtaining a second picture from said second camera; and

,

calculating a distance to an object.

40. The method of claim 39 wherein said first axial angle is substantially 45 degrees.

41. The method of claim 39 wherein said first axial angle is substantially 37 degrees.

42. The method of claim 39 wherein said first axial angle is substantially 29 degrees.

43. The method of claim 39 further comprising:

rotating said camera mount in a second axial angle between 0 and 90 degrees about a pitch axis orthogonal to said roll axis.

44. A system for calculating distances to objects within three-dimensional space in an environment comprising horizontal and vertical lines using an angled axis machine vision system comprising:

means for attaching a first camera and a second camera to a camera mount;

means for rotating said camera mount in a first axial angle between 0 and 90 degrees about a first axis;

means for obtaining a first picture from said first camera;

means for obtaining a second picture from said second camera; and

,

means for calculating a distance to an object.

45. The system of claim 44 wherein said first axial angle is substantially 45 degrees.

46. The system of claim 44 wherein said first axial angle is substantially 37 degrees.

47. The system of claim 44 wherein said first axial angle is substantially 29 degrees.

48. The system of claim 44 further comprising:

means for rotating said camera mount in a second axial angle between 0 and 90 degrees about a pitch axis orthogonal to said roll axis.