Sketch Interpretation System - Index
These pages present methods for the automatic creation of boundary
representation models of polyhedral objects from single line drawings
depicting the objects. This topic is important in that automated
interpretation of freehand sketches would remove a bottleneck in current
engineering design methods. The thesis does not consider methods which require
manual intervention or multiple drawings.
In engineering and scientific development, it is normal that a break-through
relieving an immediate bottleneck serves to either create or reveal another
(Grace Hopper, 1959).
Automatic Creation of Boundary Representation Models from Single Line Drawings
Introduction
Introduction and Context
Terminology
Previous Investigations
Discussion of Aims
Structure
Problem Statement and Proposed Solution Overview
Problem Statement
Alternatives and Possible Extensions
Solution Overview
Line Labelling
Subgraphs and Regions
Component: Parallel Lines
Component: Two-Dimensional Tidying
Component: Feature Identification
Component: Inflation
Component: Validation of Labelling
Component: Local Symmetry
Component: Classification
Component: Topological Reconstruction
Component: Face Loops
Component: Geometric Finishing
Component: Splitting and Recombination
Component: Intersecting Faces
Component: Quality Control
Chosen Components: Order and Control Structure
Background Ideas
Sketch to Drawing
Searching and Heuristics
Constraints and Optimisation
Least Squares Fit
Planar Geometry
Solid Geometry
Dual Space
Miscellaneous
Sketching and Conversion of Sketches to Line Drawings
Line Labelling
Introduction
History
Tetrahedral Junction Catalogue
Two Labelling Approaches
Results
Extended Vertices: A Problem for Line Labelling
Conclusions
Parallel Lines
Introduction
History
Reproduction of Bucketing
Partitioning into Bundles
Corners and Face Planes
Results and Recommendations
Special Sets of Parallel Lines
Features
Introduction
History
Implementation
Underslots and Valleys
Cofacial Configurations
Hole Loops from Cofacial Configurations
Results
Inflation
Introduction
History
Compliance Functions
Grimstead's Linear System Approach
Depth from Labelling
Results and Conclusions
Frontal Geometry
Local Symmetry Detection
Introduction
History
Compatibility, Pairing, Propagation
Figures of Merit
Data Identified
Mirror Chains
Results
Classification
Introduction
History
Classes
Combining Classes
Results
Reconstruction of Hidden Topology
Introduction
History
Number of Possible Completions
Control Mechanism
Move Types
Hypothesising Moves
Hypothesis Adjudication
Special-Case Recovery of Topology of Hidden Parts
Results
Geometric Finishing
Introduction
History
Constraints
Face Normals: Simple Downhill Optimisation
Face Normals: Enhanced Downhill Optimisation
Face Normals: Geometric Optimisation
Face Normals using a Genetic Algorithm
Face Distances: Simple Downhill Optimisation
Face Distances: Enhanced Downhill Optimisation
Intersecting Faces
Special Classes
Results
Results
Axis-Aligned Extrusion
Axis-Aligned Non-Extrusion
Grimstead's Block
Hole Loop
Extended Trihedral Normalon
Non-Trihedral Semi-Normalon
Semi-Normalon
Semi-Normalon
Non-Trihedral Semi-Normalon
Non-Trihedral Bracket
Conclusions
Timing
Curved Objects
Conclusions
Introduction
Line Drawing Interpretation
Sketch to Line Drawing
Features
Psychology
Appendices
Glossary
Test Drawings
Tuning Constants
Tuning: Configurable Constants
Tuning: Introduction
Tuning for the Labelling Problem
Figures of Merit
Junction Catalogue Illustrations
Trihedral Catalogue
Tetrahedral Catalogue
Geometric Analysis
Rotation Axis from Start and End Points and Angle
Bibliography
Funding for the more recent part of this investigation (i.e. everything since
my PhD Thesis) was provided by
Japan Society for the Promotion of Science
Fellowship number P03717; this support is acknowledged with gratitude.
Funding for future research comes from the
Ramon y Cajal Programme, which support is also acknowledged with gratitude.
If you're not interested in Sketch Interpretation, go to my
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