MPC 18-356 | Z. Song, Y. He, and Z. Liu Implementation of Aerial LiDAR Technology to Update Highway Feature Inventory A University Transportation Center sponsored by the U.S. Department of Transportation serving the Mountain-Plains Region. Consortium members: Colorado State University University of Colorado Denver Utah State University North Dakota State University University of Denver University of Wyoming South Dakota State University University of Utah IMPLEMENTATION OF AERIAL LIDAR TECHNOLOGY TO UPDATE HIGHWAY FEATURE INVENTORY Ziqi Song, Ph.D Assistant Professor Yi He Graduate Research Assistant Zhaocai Liu Graduate Research Assistant Department of Civil and Environmental Engineering Utah State University July 2018 Acknowledgements The funds for this study were provided by the United States Department of Transportation to the Mountain-Plains Consortium (MPC) and Utah Department of Transportation (UDOT). The authors acknowledge the following individuals from UDOT on the Technical Advisory Committee for helping to guide the research: • Lloyd Neeley • Rukhsana Lindsey • Michael Butler • Jefferson Searle • Thomas Hales • Kevin Griffin Disclaimer The contents of this report reflect the views of the authors, who are responsible for the facts and the accuracy of the information presented herein. This document is disseminated in the interest of information exchange. The report is funded, partially or entirely, by a grant from the U.S. Department of Transportation’s University Transportation Centers Program. However, the U.S. Government assumes no liability for the contents or use thereof. NDSU does not discriminate in its programs and activities on the basis of age, color, gender expression/identity, genetic information, marital status, national origin, participation in lawful off- campus activity, physical or mental disability, pregnancy, public assistance status, race, religion, sex, sexual orientation, spousal relationship to current employee, or veteran status, as applicable. Direct inquiries to: Vice Provost, Title IX/ADA Coordinator, Old Main 201, 701-231-7708, [email protected]. i ABSTRACT Highway assets, including traffic signs, traffic signals, light poles, and guardrails, are important components of transportation networks. They guide, warn, and protect drivers and regulate traffic. To manage and maintain the regular operation of the highway system, state departments of transportation (DOTs) need reliable and up-to-date information about the location and condition of highway features. The focus of this project is to analyze the capability and strengths of an airborne data collection system in highway inventory data collection. A field experiment was conducted to collect both light detection and ranging (LiDAR) point cloud data and high-resolution aerial imagery data. A comprehensive introduction to highway inventory methodologies, especially airborne LiDAR technology, was provided. An ArcGIS-based algorithm was developed to analyze and process LiDAR data as well as extract desirable features from raw LiDAR point clouds. In addition, a MATLAB-based drainage grate detection algorithm was proposed to demonstrate the effectiveness and economic efficiency of the airborne data collection system. The detection results were compared with a Mandli dataset. An economic comparison between airborne LiDAR and mobile LiDAR was also provided. From the results of this project, we can conclude that airborne LiDAR technology is a promising method for road inventory data collection. ii TABLE OF CONTENTS 1. INTRODUCTION ................................................................................................................................ 9 1.1 Problem Statement ........................................................................................................................... 9 1.2 Research Objectives ....................................................................................................................... 10 1.3 Expected Contributions .................................................................................................................. 10 1.4 Outline of the Report ..................................................................................................................... 10 2. INTRODUCTION OF ROAD SURVEYING METHODOLOGIES ................................................ 11 2.1 Manual/Field Inventory ................................................................................................................. 11 2.2 Photo/Video Log ............................................................................................................................ 12 2.3 Integrated GPS/GIS Mapping System ........................................................................................... 13 2.4 Aerial/Satellite Photography .......................................................................................................... 14 2.5 LiDAR ........................................................................................................................................... 15 3. LIDAR ................................................................................................................................................ 16 3.1 What Is LiDAR .............................................................................................................................. 16 3.2 How LiDAR Works ....................................................................................................................... 17 3.3 LiDAR Classification..................................................................................................................... 17 3.3.1 Airborne Laser Scanning (ALS)............................................................................................ 17 3.3.2 Mobile Laser Scanning (MLS) .............................................................................................. 18 3.3.3 Terrestrial Laser Scanning (TLS) .......................................................................................... 19 3.4 Comparison of LiDAR ................................................................................................................... 20 3.5 Airborne LiDAR ............................................................................................................................ 20 3.5.1 Background and History ........................................................................................................ 20 3.5.2 Components ........................................................................................................................... 21 3.5.3 Flight Management System ................................................................................................... 21 3.5.4 Airborne Platform ................................................................................................................. 21 3.5.5 Laser Scanner ........................................................................................................................ 22 3.5.6 Position and Orientation System ........................................................................................... 22 3.5.7 Control and Data Recording Unit .......................................................................................... 22 3.6 Applications of ALS in Transportation .......................................................................................... 22 3.6.1 Traffic Flow Estimation ........................................................................................................ 22 3.6.2 Highway Corridor Mapping .................................................................................................. 22 3.6.3 Integrated Uncertainties of Traffic Island Modeling ............................................................. 23 3.6.4 Collecting and Recording Highway Inventory ...................................................................... 23 iii 3.6.5 Expanding Highway Projects ................................................................................................ 23 4. FIELD EXPERIMENT AND DATA COLLECTION ....................................................................... 24 4.1 Methodology .................................................................................................................................. 24 4.2 Data Collection .............................................................................................................................. 25 4.3 Data Preprocessing......................................................................................................................... 28 4.4 Accuracy of LiDAR Data .............................................................................................................. 33 5. AIRBORNE LIDAR DATA PROCESSING USING ARCGIS ........................................................ 39 5.1 Introduction .................................................................................................................................... 39 5.2 ArcGIS-based Feature Extraction Algorithm ................................................................................ 43 5.3 Road Assets Inventory ................................................................................................................... 45 5.3.1 I-84 ........................................................................................................................................ 45 5.3.2 US-191 .................................................................................................................................