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Updated: Jul 31, 2026
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Implementation of Portable Emissions Measurement Systems (PEMS) for the Real-driving Emissions (RDE) Regulation in Europe
Published on: December 4, 2016
Road grade estimation for on-road vehicle emissions modeling using light detection and ranging data.
Kaishan Zhang1, H Christopher Frey
1North Carolina State University, Department of Civil, Construction, and Environmental Engineering, Raleigh, NC 27695, USA. frey@eos.ncsu.edu
Journal of the Air & Waste Management Association (1995)
|June 30, 2006
Summary
Estimating road grade using LIDAR data improves vehicle emissions modeling. This method offers a reliable alternative for portable emissions monitoring systems (PEMS) when direct road grade measurement is difficult.
Area of Science:
- Environmental Science
- Transportation Engineering
- Remote Sensing
Background:
- Vehicle-specific power (VSP) is crucial for understanding real-world vehicle emissions measured by portable emissions monitoring systems (PEMS).
- Road grade significantly impacts VSP and emissions, but is challenging to measure accurately with PEMS.
- Existing methods for road grade estimation are insufficient for precise emissions analysis.
Purpose of the Study:
- To develop and evaluate a reliable method for estimating road grade using Light Detection and Ranging (LIDAR) data.
- To assess the accuracy and applicability of LIDAR-based road grade estimation for vehicle emissions modeling.
- To provide an alternative to direct road grade measurement for PEMS applications.
Main Methods:
- Utilized LIDAR data buffered onto roadway maps via a Geographic Information System (GIS).
- Defined roadway segments based on vertical curvature criteria.
- Quantified roadway elevations and estimated road grade and banking by fitting a plane to each segment.
- Evaluated the method using interstate highway data and design drawings.
Main Results:
- LIDAR data proved reliable and accurate for estimating road grade.
- The developed method effectively addresses the challenge of measuring road grade with PEMS.
- A case study demonstrated the application of LIDAR-based road grade data with PEMS data.
Conclusions:
- LIDAR-based road grade estimation is a viable and accurate technique for vehicle emissions modeling.
- This method enhances the utility of PEMS by overcoming road grade measurement limitations.
- Accurate road grade data derived from LIDAR supports more precise real-world emissions assessments.
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