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Objective Surface Inspection and Semi-Automated Material Removal for Metal Castings

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Objective Surface Inspection and Semi-Automated Material Removal for Metal Castings Iowa State University Capstones, Theses and Graduate Theses and Dissertations Dissertations 2021 Objective surface inspection and semi-automated material removal for metal castings Daniel Wilhelm Schimpf Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/etd Recommended Citation Schimpf, Daniel Wilhelm, "Objective surface inspection and semi-automated material removal for metal castings" (2021). Graduate Theses and Dissertations. 18607. https://lib.dr.iastate.edu/etd/18607 This Dissertation is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Graduate Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. i Objective surface inspection and semi-automated material removal for metal castings by Daniel Wilhelm Schimpf A dissertation submitted to the graduate faculty in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Major: Industrial Engineering Program of Study Committee: Frank Peters, Major Professor Michael Dorneich Matthew Frank Yan-Bin Jia Stephen Vardeman The student author, whose presentation of the scholarship herein was approved by the program of study committee, is solely responsible for the content of this dissertation. The Graduate College will ensure this dissertation is globally accessible and will not permit alterations after a degree is conferred. Iowa State University Ames, Iowa 2021 Copyright © Daniel Wilhelm Schimpf, 2021. All rights reserved. ii TABLE OF CONTENTS Page LIST OF FIGURES ....................................................................................................................... iv LIST OF TABLES ....................................................................................................................... viii ACKNOWLEDGEMENT ............................................................................................................. ix ABSTRACT .....................................................................................................................................x CHAPTER 1. GENERAL INTRODUCTION ................................................................................1 1.1. Introduction ..................................................................................................................... 1 1.2. Dissertation Organization ............................................................................................... 4 References ................................................................................................................................. 4 CHAPTER 2. LITERATURE REVIEW .........................................................................................5 2.1. Inspection ........................................................................................................................ 5 2.2. Material Removal .......................................................................................................... 12 References ............................................................................................................................... 16 CHAPTER 3. VARIOGRAM ROUGHNESS METHOD FOR CASTING SURFACE CHARACTERIZATION ...............................................................................................................19 Abstract .................................................................................................................................... 19 3.1 Statement of Authorship ............................................................................................... 20 3.2 Introduction ................................................................................................................... 20 3.3 Methods ......................................................................................................................... 26 3.3.1 Spatial Information .................................................................................................... 26 3.3.2 Underlying Geometry ................................................................................................ 29 3.3.3 Abnormalities ............................................................................................................ 32 3.4 Combining Underlying Geometry, Abnormalities, and Variogram Roughness ........... 35 3.5 Results ........................................................................................................................... 37 3.6 Discussion ..................................................................................................................... 46 References ............................................................................................................................... 47 CHAPTER 4. 3D ANALYSIS OF CASTING SURFACE CHARACTERIZATION BASED ON THE VARIOGRAM ROUGHNESS METHOD ....................................................................49 Abstract .................................................................................................................................... 49 4.1. Statement of Authorship ............................................................................................... 50 4.2. Introduction ................................................................................................................... 50 4.3. Methods ......................................................................................................................... 53 4.4. Results ........................................................................................................................... 62 4.5. Discussion ..................................................................................................................... 69 References ............................................................................................................................... 71 iii CHAPTER 5. SECTIONING METHOD FOR AUTOMATIC PATH PLANNING: ROBOTIC GRINDING FOR HIGH VARIETY, LOW VOLUME PRODUCTION ...................74 Abstract .................................................................................................................................... 74 5.1 Statement of Authorship ............................................................................................... 75 5.2 Introduction ................................................................................................................... 75 5.3 Methods ......................................................................................................................... 80 5.3.1 Setup ................................................................................................................ 81 5.3.2 Segmentation and Removal Method ................................................................ 84 5.4 Results ......................................................................................................................... 106 5.5 Discussion ................................................................................................................... 109 References ............................................................................................................................. 111 CHAPTER 6. GENERAL CONCLUSION .................................................................................114 6.1 Conclusion ....................................................................................................................... 114 6.2 Future work ...................................................................................................................... 115 iv LIST OF FIGURES Page Figure 2-1: GAR C-9 ...................................................................................................................... 6 Figure 2-2: ACI Surface Indicator Scale ........................................................................................ 6 Figure 2-3: Various SCRATA comparators. First row left to right: A1, A2, A3, A4. Second row left to right: B4, C3, D5, E3 ................................................................................ 9 Figure 3-1 A1 through A4 SCRATA plates (left to right). ........................................................... 22 Figure 3-2 GAR microfinish comparator C9. ............................................................................... 22 Figure 3-3 Results of 5 profilometer measurements on each roughness level of the GAR-C9 plate. ......................................................................................................................... 23 Figure 3-4 Variogram with correlation length and variogram roughness (0-3 mm). ................... 29 Figure 3-5 Underlying geometry and distance adjustment. .......................................................... 31 Figure 3-6 Abnormality detection based on image analysis. ........................................................ 34 Figure 3-7 SCRATA E3 point cloud before (top) and after (bottom) abnormality removal. ....... 34 Figure 3-8 Process pipeline. .......................................................................................................... 36 Figure 3-9 Created test point clouds. ............................................................................................ 39 Figure 3-10 Variogram for test point clouds................................................................................
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