US 10,319,108 B2 · System and method for machine vision object orientation measurement

Abstract

Disclosed are methods and systems for measuring orientation parameters of spherical objects by image processing. Geometric shapes detected in a captured image are measured by generating and scoring models of the geometric shapes, where a high numerical score indicates a good match of the model to the image. The orientation parameters are computed from the geometric parameters measured from the image. A fast, precise, and accurate measurement requires generation and scoring be computationally efficient, meaning that many high-scoring models are generated in a short period of time. Disclosed are embodiments for a multistep measurement process for measuring the orientation parameters of an artificial hip joint from an x-ray image, measuring rotation of a basketball from video frame images, and navigating a spacecraft utilizing sunlight incident on a planetary body.

Claims23

Dependent claims

A method for measuring orientation parameters of a physical object comprising:

acquiring a first image of the physical object, wherein at least a portion of the physical object is spherical;
selecting a first region of interest in the first image;
performing a circular random sample consensus operation on the first region of interest to detect a reference circle;
cropping the first region of interest to the image portion inside the reference circle;
performing a first semiellipse random sample consensus operation on the cropped first region of interest to detect a first primary semiellipse;
computing a first set of measured orientation parameters of the object from geometric parameters of the first primary semiellipse, wherein the first primary semiellipse indicates at least a portion of a first primary great circle discernible on the physical object;
whereby the orientation parameters of the physical object are measured from the acquired image.

4 more elements

A system for measuring the orientation of an object comprising:

an image acquisition component wherein an image of the object is acquired, wherein at least a portion of the object is spherical;
a central processing unit configured to execute instructions comprising:
an image processing selection module configured to select a region of interest in the image,
an image processing object identification module configured to perform a circular random sample consensus operation on the region of interest to detect a reference circle, to crop the region of interest to the image portion inside the reference circle, to perform a semiellipse random sample consensus operation on the cropped region of interest to detect a semiellipse, wherein the semiellipse indicates at least a portion of a first primary great circle discernible on the object, to compute a set of measured orientation parameters of the object from geometric parameters of the semiellipse.

1 more element

Dependencies are inferred from the claim text.

System and method for machine vision object orientation measurement

Life of this patent

System and method for machine vision object orientation measurement

Life of this patent

Abstract

Claims23