Intelligent Seam Tracking for Robotic Welding

1 Introduction.- 1.1 Industrial Robotic Applications.- 1.2 An Overview of Robotic Welding.- 1.3 Outline of the Monograph.- 2 An Overview of Seam Tracking Technology.- 2.1 Introduction.- 2.2 Through-the-Arc Sensing.- 2.3 3D Vision Sensing.- 2.4 Evolution of Seam Tracking Strategies for Vision-based Systems.- 2.5 Summary.- 3 Feature Extraction and Seam Recognition Techniques.- 3.1 Introduction.- 3.2 Intensity Image Preprocessing.- 3.3 Range Image Preprocessing.- 3.4 Feature Extraction and Seam Recognition.- 3.5 Seam Environment Model.- 3.6 Summary.- 4 Coordinate Frames for Realtime Seam Tracking.- 4.1 Introduction.- 4.2 Base Coordinate Frame ([W]).- 4.3 Torchtip Coordinate Frame [T].- 4.4 Sensor Coordinate Frame [S].- 4.5 Seam Coordinate Frame [C(k)].- 4.6 Summary.- A.1 PPV to Range Conversion.- 5 Seam Tracking in an Unstructured Environment: A Case Study with Vee-Groove Joints.- 5.1 Overview.- 5.2 Definitions.- 5.3 Range Image Processing.- 5.4 Seam Environment Model & High-Level Control.- 5.5 Geometric Model of the Seam.- 5.6 Robot Motion Control (Weld Path Generation).- 5.7 Summary.- B.1 Least Squares Approximation Polynomials.- 6 Implementation Concerns in Seam Tracking Systems.- 6.1 Introduction.- 6.2 System Description.- 6.3 System Control Software.- 6.4 System Operation.- 6.5 Synchronizing Concurrent Operations in Seam Tracking.- 6.6 Summary.- C.1 Laser Profiling Gage Calibration.- 7 Tracking Accuracy & Error Analysis.- 7.1 Is The Tracking Error Bounded?.- 7.2 Sources of Error.- 7.3 Minimum Radius of Curvature for the Seam.- 7.4 Summary.- D.1 Robot Accuracy Issues.- 8 Seam Tracking System Prototypes.- 8.1 Ultrasonic Ranging-Based Seam Tracking.- 8.2 Automatix Inc.'s Vision-aided Robotic Welder.- 8.3 PASS-Visual Sensing for Tracking and Online Control.- 8.4 ASEA Robotics' Adaptive Torch Positioner.- 8.5 A Realtime Optical Profile Sensor for Robot Welding.- 8.6 LaserTrak-Seam Tracker for Arc Welding Applications.- 8.7 ESPRIT-Realtime Imaging for Arc Welding.- 8.8 Summary.- 9 Future Directions.- 9.1 Introduction.- 9.2 Scope of Future Enhancements.- 9.3 Error Analysis.- 9.4 Summary.- References.