Method and apparatus for registering a known digital object to scanned 3-D model

A workstation adapted to form a virtual three-dimensional model of an object, wherein said object comprises a first object attached to a second object, comprising:

• a central processing unit;
• a memory storing a scanned virtual three-dimensional model of said object in the form of a point cloud obtained from scanning said object, said scanned virtual three-dimensional model having a first portion thereof corresponding to scanning of said first object, wherein said first object is of a known structure;
• said known structure of predetermined three-dimensional configuration, wherein said first portion is a less than an ideal three-dimensional representation of said known structure;
• said memory further storing a pre-existing three-dimensional digital model corresponding to said known structure;
• and
• software executable by said central processing unit for registering said pre-existing three-dimensional digital model to a portion of said point cloud corresponding to said first portion to form a three-dimensional surface;
• wherein said software for registering comprises software for calculating minimum distance vectors from every point in said portion of said point cloud to said pre-existing three-dimensional digital model and excluding those points from said three dimensional surface whose minimum distance vectors exceed a predefined value;
• and for forming the virtual three-dimensional model of said object from said scanned virtual three-dimensional model of said object, said virtual three-dimensional model of said object including said three-dimensional surface.

An apparatus for constructing a virtual three-dimensional model of an object, wherein said object comprises a first object attached to a second object, comprising:

• means for scanning said object;
• means for creating a scanned virtual three-dimensional model of said object in the form of a point cloud from said scanning step with the aid of a computer, said scanned virtual three-dimensional model having a first portion thereof corresponding to scanning of said first object, wherein said first object is of a known structure, said known structure of predetermined three-dimensional configuration, wherein said first portion is a less than an ideal three-dimensional representation of said known structure;
• means for retrieving a pre-existing three-dimensional digital model from a memory, said pre-existing three-dimensional digital model corresponding to said known structure;
• means for registering said pre-existing three-dimensional digital model to a portion of said point cloud corresponding to said first portion to form a three-dimensional surface;
• wherein said means for registering comprise means for calculating minimum distance vectors from every point in said portion of said point cloud to said pre-existing three-dimensional digital model and excluding those points from said three dimensional surface whose minimum distance vectors exceed a predefined value;
• and
• means for forming said virtual three-dimensional model of said object from said scanned virtual three-dimensional model of said object, said virtual three-dimensional model including said three-dimensional surface.

A method of constructing a virtual three-dimensional model of an object having a predefined geometry from a scanner, a data processing system, and at least one machine-readable memory accessible to the data processing system, comprising the steps of:

• (a) scanning the object with the scanner and responsively obtaining a three-dimensional surface of said object in the from a point cloud;
• wherein said three-dimensional surface of said object is a less than an ideal three-dimensional representation of said object;
• (b) obtaining a pre-existing three-dimensional digital model of said object from said memory;
• and
• (c) registering said three-dimensional surface in the from said point cloud to said pre-existing three-dimensional digital model to thereby produce the virtual three-dimensional model of said object;
• wherein said registering step comprises calculating minimum distance vectors from every point in said point cloud to said pre-existing three-dimensional digital model and excluding those points from said three dimensional surface whose minimum distance vectors exceed a predefined value.

A method of constructing a virtual three-dimensional model of an object having a predefined geometry from a scanner, a data processing system, and at least one machine-readable memory accessible to the data processing system, comprising the steps of:

• (a) scanning the object with the scanner and thereby obtaining a first and a second two-dimensional images of the object, wherein during scanning the scanner and object are moved relative to each other;
• (b) processing the first and second images with the data processing system so as to convert the two-dimensional images into a data set representing a point cloud comprising individual points, each point comprising a location in a three-dimensional coordinate system;
• (c) obtaining a pre-existing three-dimensional digital model of the object;
• and
• (d) further processing the data set representing the point cloud with the data processing system so as to register the point cloud relative to the pre-existing three-dimensional digital model to thereby produce the virtual three-dimensional model of the object;
• wherein said registering step comprises calculating minimum distance vectors from every point in said point cloud to said pre-existing three-dimensional digital model and excluding those points from said virtual three-dimensional model of the object whose minimum distance vectors exceed a predefined value.

A method of determining a location of a virtual three-dimensional model of an object of known geometry, comprising the steps of:

• a) scanning said known object and generating a set of images;
• b) converting said set of images into a point cloud;
• c) retrieving said virtual three-dimensional model of said object from memory;
• and
• d) registering said point cloud to said virtual three-dimensional model of said object to thereby verify in three-dimensional space the position of said virtual three-dimensional model of said object;
• wherein said registering step comprises calculating minimum distance vectors from every point in said point cloud to said virtual three-dimensional model of said object and excluding those points from said virtual three-dimensional model of said object whose minimum distance vectors exceed a predefined value.

A method of registering a first digital model of a dental appliance to a three-dimensional representation of said dental appliance as a result of scanning, comprising the steps of:

• p1 a) scanning said dental appliance and generating a first set of images;
• b) converting said first set of images into a three-dimensional representation of said dental appliance in the form of a point cloud;
• c) retrieving said first digital model of said dental appliance from a digital library;
• d) fitting said three-dimensional representation in the form of said point cloud to said first digital model to thereby register said first digital model to said three-dimensional representation and generate a revised three dimensional representation of the dental appliance;
• wherein said registering step comprises calculating minimum distance vectors from every point in said point cloud to said first digital model of said object and excluding those points from said three-dimensional representation whose minimum distance vectors exceed a predefined value.