SHRP-H-674 Fabrication and Testing of Automated Pothole Patching Machine James R. Blaha BIRL Northwestem University 1801 Maple Avenue Evanston, IL 60201 Strategic Highway Research Program National Research Council Washington, DC 1993 SHRP-H-674 Contract H- 107B Product Code: 3005 Program Manager: Don M. Harriott Project Manager: Shashikant Shah Production Editor: Marsha Barrett Program Area Secretary: Carina Hreib October 1993 key words: asphalt pavement repair automated pothole patching machine hot air lance pothole repair robotics spray patching spray emulsion Strategic Highway Research Program National Academy of Sciences 2101 Constitution Avenue N.W. Washington, DC 20418 (202) 334-3774 The publication of this report does not necessarily indicate approval or endorsement of the findings, opinions, conclusions, or recommendations either inferred or specifically expressed herein by the National Academy of Sciences, the United States Government, or the American Association of State Highway and Transportation Officials or its member states. © 1993 National Academy of Sciences Acknowledgments The research described herein was supported by the Strategic Highway Research Program (SHRP). SHRP is a unit of the National Research Council that was authorized by section 128 of the Surface Transportation and Uniform Relocation Assistance Act of 1987. °.° I11 Contents °°° Acknowledgments ..................................................................................................... m List of Figures ............................................................................................................. vii List of Tables .............................................................................................................. ix Abstract ...................................................................................................................... xi Executive Summary ..................................................................................................... xiii 1. Research Program .................................................................................................. 1 Perspective ...................................................................................................... 1 Objectives ........................................................................................................ 1 Research Plan .................................................................................................. 1 Research Results and Benefits .......................................................................... 2 Problem Definition: The Hole Problems .......................................................... 3 Pothole Definition ............................................................................................ 5 Pothole Location .................................................................................. 5 Pothole Spacing ................................................................................... 5 Adjacent Surfaces and Structures ......................................................... 7 Repair Conditions ................................................................................. 8 Repair Materials ................................................................................... 9 Comparison of the Standard Repair Procedures ................................................ 9 Economics of Manual Versus Automated Patching ........................................... 10 2. Development of Concept Design ............................................................................. 14 Design Methodology ........................................................................................ 14 Basic Design Objectives ................................................................................... 14 System-Level Design ....................................................................................... 14 Automated Repair Procedure ........................................................................... 16 Component Design .......................................................................................... 18 Truck Base ........................................................................................... 19 Repair Enclosure Module ..................................................................... 19 Pavement Cutter Module .......................... :........................................... 19 Vacuum System Module ....................................................................... 19. Heating System Module ....................................................................... 19 Filling System Module .......................................................................... 19 Computer Vision System Module ......................................................... 20 Remote Manipulator Module ................................................................ 20 Concept Design Evaluations ............................................................................. 20 Concept Design Areas .......................................................................... 20 V Concept Ranking and Selection Process ................................................ 21 Vehicle System Concept Design ....................................................................... 23 3. Feasibility Testing of Concepts ............................................................................... 25 Cutting Evaluations .......................................................................................... 25 Vacuum Evaluations ........................................................................................ 26 Heating Evaluations ......................................................................................... 27 Patching Evaluations ........................................................................................ 28 Computer Vision Evaluations ........................................................................... 31 Remote Manipulator Evaluations ..................................................................... 34 4. Development and Testing of First Generation Equipment ........................................ 37 Scale Model ..................................................................................................... 37 Repair Enclosure .............................................................................................. 38 Pavement Cutter .............................................................................................. 38 Vacuum System ............................................................................................... 39 Heating System ................................................................................................ 41 Spray Filling ..................................................................................................... 44 Computer Vision System .................................................................................. 46 Robot Manipulator ........................................................................................... 48 5. Development of Final Vehicle Prototype ................................................................. 50 Vehicle Cab and Chassis .................................................................................. 50 Component Layout .......................................................................................... 55 Assembly and Integration ................................................................................. 57 Review of Objectives ....................................................................................... 57 Automated Pothole Repair Procedure .............................................................. 60 6. Conclusions and Recommendations ........................................................................ 62 Commercialization Potential ............................................................................. 64 Field Test Program .......................................................................................... 64 Benefits ........................................................................................................... 65 7. References .............................................................................................................. 67 Appendix A: Potholes and Their Repair with Asphalt Materials Appendix B: Pothole Patching Cost Comparisons Appendix C: Alternative Conceptual Designs Appendix D: Operational Requirements Appendix E: Pavement Cutter Prototype Appendix F: Vacuum Cleaning Prototype Appendix G: Computer Vision Prototype Appendix H: Robot Manipulator Prototype Appendix I: Operating Procedural Guide vi List of Figures Figure 1-1. Representative Pothole .......................................................................... 4 Figure 1-2. Pothole Spacing Along a Pavement ........................................................ 6 Figure 1-3. Curb\Gardrail Access Problem for a Pothole Repair Vehicle .................. 7 Figure 1-4. Four Principal Climatic Regions of the U.S ............................................ 8 Figure 1-5. Estimated Economics of Manual Patching Versus Automated ............... 12 Figure 2-1. System-Level Vehicle Concepts ........................... i................................ 15 Figure 2-2. Automated Repair Sequence Flow Diagram .......................................... 17 Figure 2-3. Major Equipment Modules of the Repair System .................................. 18 Figure 2-4. Early Concept Drawing