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The term Intelligent Transportation Systems (ITS) was coined over two decades ago to designate applications of information and communication technologies to the operational management of transportation networks. The main promise of ITS has been very consistent over that period: network capacity can be freed up by optimizing traffic controls and empowering users with accurate travel information. It can be debated how much faith practitioners and policy makers have placed in technology by investing their resources, as well as the extent to which Intelligent Transportation Systems have delivered on their promise. However, there is no question that steady and sometimes spectacular advances in computing technologies and usage trickle down to transportation applications in important ways. As a result, new products and services emerge continuously. They include systems that address the direct needs of networks managers, as well as others that are developed in tangential markets (e.g. automotive) or even through non-market mechanisms (e.g. many mobile web applications). This talk presentation reviews major trends in information and communication technologies and demonstrate how each of them is driving innovative transportation services. We attempt to envision how those trends might develop in the future, so that we can finally examine some of their implications for travel demand and network management. There lie both challenges and opportunities for transportation engineers and planners, but either way, profound changes appear inevitable.
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Intelligent Transportation Trends and Perspectives
2011
J.D. Margulici
jdm@novavia.us
www.novaviasolutions.com
Chapter 3: Traffic Monitoring
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ITS primer and brief history
State of the art: traffic monitoring
Information technology trends
Prospective and implications
J.D. Margulici
jdm@novavia.us
www.novaviasolutions.com
Intelligent Transportation
Trends and Perspectives
2011
You cannot manage what you cannot measure…
3
Traffic sensors are the technological backbone enabling system
management
ITS Trends and Perspectives - April 2011
Traffic Sensors: State of the Art
4 ITS Trends and Perspectives - April 2011
Sensor Data
5
Point Detection
• Fixed locations
• Samples volume, occupancy, speed
Segment Detection
• Fixed segments
• Samples travel times
Floating Data
• Possibly random locations
• Samples speed
n(x,t) k(x,t) v(x,t)
T(i,[x1,x2])
v(x,t)
Completeness True Trips Coverage
ITS Trends and Perspectives - April 2011
Traffic Sensors: Point Detection
Inductive Loop (ILD)
Doppler Radar
Video
Doppler Microwave
Passive Acoustic
ITS Trends and Perspectives - April 2011 6
Segment Reading
Toll Tag Readers
License Plate Readers
Magnetic Signature
Bluetooth / MAC ID
ITS Trends and Perspectives - April 2011 7
Travel Time from Portable ALPR
CA-154
Two-lane local highway
Length: 31 miles
Winding
Slow speeds
US-101
4-lane national divided highway
Length: 47 miles
ITS Trends and Perspectives - April 2011 8
0
100
200
300
400
500
600
700
800
900
0:00 3:00 6:00 9:00 12:00 15:00 18:00 21:00
Vo
lum
e (
Ve
hic
les)
Time of day
Average Hourly Volume at CA154NB
Tube Count LPR Camera Count Matched Plate Count
Floating Car Data
ITS Trends and Perspectives - April 2011 9
Mobile Century: GPS-Equipped Phones as Traffic Probes…
ITS Trends and Perspectives - April 2011 10
Mobile Century: Design of Experiment
165 Berkeley students drivers
100 GPS-enabled cell phones (N95)
100 rented cars
6 to 10 mile loops, I-880
10am to 7pm
2-5% penetration rate
1/3Hz data stored on phones
Real-time, online flow reconstruction (VTLs)
ITS Trends and Perspectives - April 2011 11
Mobile Century 2.8.8
ITS Trends and Perspectives - April 2011 12
12
Virtual Trip Lines vs. Local Log vs. Speedometer
ITS Trends and Perspectives - April 2011 13
P.M.
A.M.
Penetration Rates
ITS Trends and Perspectives - April 2011 14
Collected Trajectories (20% subset)
ITS Trends and Perspectives - April 2011 15
Shockwave
ITS Trends and Perspectives - April 2011 16
Contour Plots
Loop Detectors Phone Logs
ITS Trends and Perspectives - April 2011 17
Contour Plots (2)
ITS Trends and Perspectives - April 2011 18
Speed Scale
17 Loops
17 VTLs
Phone Logs
30 VTLs
Video Validation
ITS Trends and Perspectives - April 2011 19
Travel Times
ITS Trends and Perspectives - April 2011 20
Speed Dating: Loops + VTL…
ITS Trends and Perspectives - April 2011 21
Traveler Information
22 ITS Trends and Perspectives - April 2011
511
ITS Trends and Perspectives - April 2011 23
2003
December 10, 2010
Traffic Information: Value Chain
24
Data Collection
Data Processing
Delivery Channels
Application Packaging
Roadway Sensors
Probe Data
Incident Data
Weather & Events
Filter & Interpret
GIS Integration
Aggregate Predict
Radio Broadcasting
Web Publishing
TV Reports Mobile
Delivery
Phone / PDA Apps.
Navigation Units
Trip Planning
Logistics & Professional
Branding & Distribution
Mobile Networks
Car Makers
Information Portals
Mass Media
Surface Streets
Freeways
ITS Trends and Perspectives - April 2011
Real-time Traffic Detection: Supply and Demand
Infrastructure-Side Technology Vehicle-Side Technology
25
Worldwide Navigation Units Sales (10,000s)
Source: SiRF Technology Source: ITS Joint Projects Office
U.S. Freeway Miles Covered with Real-time Detection
3,900
Actual
ITS Trends and Perspectives - April 2011
Procurement of Private Data
ITS Trends and Perspectives - April 2011 26
$2 million appropriated for data services in up to 25 metro areas
Traffic.com deploys, operates and maintains sensor network
Traffic.com provides data to TV, radio, satellite radio, in-vehicle systems, and maintains public Web site
Agencies get unlimited real-time and archived data for internal use
Federal Intelligent Transportation Infrastructure Program
Procurement
• Data quality audits, QA
• Licensing rights
Systems Integration
• Traffic systems operate with volume/occupancy
• GIS integration with different segment definitions
Data Policies
• What fusion / selection procedures?
• Where are detectors still needed?
Current Challenges
Traffic Information Quality
Traffic information has become abundant but quality remains seldom monitored
• End users are relatively clueless about information quality
• Margins of error are not well understood and used in practice
There are no widespread metrics or evaluation procedures to measure data quality
• Each customer (e.g. car manufacturer, DOT…) conducts its own benchmark
• Evaluation results cannot be readily compared
Postulate:
Harmonized benchmarking methods would benefit both suppliers and customers
• Improve consistency and fairness of evaluations
• Lower overall costs by eliminating duplication of efforts
• Better recognize true value-added and pull quality upward
27 ITS Trends and Perspectives - April 2011
About NATWG
The North American Traffic Working Group (NATWG) works collaboratively to define, accept and advocate for the unique needs of North America traffic information services. NATWG seeks to develop a coordinated, proactive market driven implementation of traffic and travel information services and products by both influencing international standards efforts and coordinating the development of non-competitive commercial agreements.
Members sampling:
28 ITS Trends and Perspectives - April 2011
Key Takeaway
ITS Trends and Perspectives - April 2011 29
If counting cars keeps you awake at night, start counting sheep instead…
Intelligent Transportation Trends and Perspectives
2011
J.D. Margulici
jdm@novavia.us
www.novaviasolutions.com
Next is Chapter 4: Vehicle Technology
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