Mobile LiDAR infrastructure inventory survey techniques are preferred by state DOTs where data quality and completeness are top priority.

A review of highway inventory data collection methods vital to the implementation of the Highway Safety Manual (HSM) at the state level.

Date Posted
08/14/2018
Identifier
2018-B01288
TwitterLinkedInFacebook

A Comprehensive Assessment of Highway Inventory Data Collection Methods

Summary Information

This study presented the results of a national survey conducted to evaluate the following state DOT infrastructure inventory data collection techniques:



Aerial/Satellite Imagery - High resolution images are taken from aircraft or satellite to identify and extract highway inventory information.



Field Inventory - GPS survey equipment and conventional optical are sued to collect desired information in the field.



Photo/Video Log - Instrumented vehicles automatically record photo/video data that can be examined later to extract information.



Integrated GPS/GIS Mapping - An integrated GPS/GIS field data logger is used to record and store inventory information.



Mobile LiDAR - Instrumented vehicles collect 3-D precision point information using LiDAR systems traveling at highway speeds.



Airborne LiDAR - Instrumented aircraft collect 3-D precision point information using LiDAR systems to derive highway inventory data.



METHODOLOGY



Survey respondents were requested to indicate their level of satisfaction with their primary collection method using a scale of 1 to 5 (representing unacceptable, fair, good, very good, and excellent, respectively) where one is worst and five is the best with regard to cost, time, accuracy, safety, and data storage requirements.



The satisfaction indicators considered in the survey included equipment cost, data accuracy, data completeness, crew hazard exposure, data collection cost, data collection time, data reduction cost, data reduction time, and data storage requirement.

FINDINGS



Findings were based on data collected from 30 respondent state DOTs. More than 50 percent of responding states use field inventory, integrated GPS/GIS mapping, video log, and aerial imagery for collecting roadside feature data. Satisfaction levels with their primary data collection method are shown below.

 

Satisfaction Factors

Satellite Imagery

Photo log

Aerial Imagery

Field Inventory

Video log

Integrated GPS/GIS Map

Mobile LiDAR

Airborne LiDAR

Equipment Cost

3.1

3

3.1

3.1

3.1

2.9

2

2.5

Data Accuracy

3.3

3.5

3.6

3.5

3.4

3.8

3

3

Data Completeness

3.2

3.3

3.3

3.4

3.3

3.3

3.4

2.8

Crew Hazard Exposure

3.2

3.4

2.9

2.9

2.9

3

2.5

3

Data Collection Cost

3.2

2.9

3

2.8

3

2.8

2.5

2.5

Data Collection Time

3.2

2.8

2.9

2.8

2.8

2.7

2.6

2

Data Reduction Time

2.8

3.1

2.9

3.1

2.8

2.9

2

2

Data Reduction Cost

3.2

3.1

2.9

2.7

2.8

2.8

2.5

2

Data Storage Requirement

3.2

3.5

3.4

3.3

3.1

3.3

3

3.4