B2. Vehicle-Based Surveys

ISCTSC 2008 – Annecy, France

Administrative data

• Vehicle Registration files are maintained by nearly all countries

– Provides detailed information on the vehicle fleet – Can use registry files to sample motor vehicle use

• Vehicle inspection programmes potential source of odometer readings (VKT)

• Issues• File integrity

– scrapped vehicles not removed

• Confidentiality– Not every country allows access for sampling

• Coverage– Foreign vehicles not covered

Roadside interviews

• Largely local in scope – Cordon/screenlines in urban areas– Helsinki/Stuttgart ANPR-based O-D surveys– Toll road planning

• Methodology issues– O-D flows dependent on where the vehicles are

surveyed (geographic bias)– Study area needs to be tightly defined– Requires field deployment

• Safety concerns• Burden (survey needs to be short)• Data quality since sites are temporary

Traffic counts

• Nearly universal– Data are collected for a network of

permanent/short-term sites using machine-based and manual counts

– Works best on motorways/arterials– Can estimate VKT by road class and vehicle

class

• Management of networks a challenge– Sites widely dispersed– High maintenance and data collection costs

• Truck classification differs across countries• comparability

Different Technologies (1)

• GPS– Offers routing, more precise O-D, time/speed

profiles, elevation– Cold start problem leads to gaps– Urban canyons/tunnels block signal– Purpose not known but can impute from land use

• On-Board Diagnostics (OBD-II)– All North American vehicles model year 1996 and

newer must carry an OBD-II data port– Can collect extensive vehicle performance

information passively• Instantaneous fuel use• Speed ranges• Coolant temperatures

Different Technologies (2)

• Automatic number plate recognition (ANPR)

– Use camera and OCR technology to collect license plate data• Travel time/O-D via direct plate matching• Can use vehicle registry as a sampling base

(not available in all jurisdictions)

– Uses• Enforcement• Fraud detection• Heavy goods movement• Foreign vehicles

Different Technologies (3)

• Electronic toll tags

• Electronic number plates

• Weigh-in-motion

• Cell-phone tracking

• Assisted GPS (A-GPS)

Research priorities for vehicle-based surveys

• Fuel and emissions– More detailed information on fuel

use/emissions profiles

• Road safety– Where accidents occur (GPS)

• Road user charging

• Tapping full use of new technologies– Reduce burden of collecting vehicle use

data