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VDOT’s Connected Vehicle Program. Noah Goodall, Ph.D., P.E. Research Scientist Virginia Center for Transportation Innovation and Research ASHE Old Dominion Section Meeting June 13, 2013. Smartphones. Very sophisticated computer Sensors GPS 3-axis accelerometer Camera Magnetometer
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VDOT’s Connected Vehicle Program Noah Goodall, Ph.D., P.E. Research Scientist Virginia Center for Transportation Innovation and Research ASHE Old Dominion Section Meeting June 13, 2013
Smartphones • Very sophisticated computer • Sensors • GPS • 3-axis accelerometer • Camera • Magnetometer • Carried with you all day
Modern Vehicles – Very Sophisticated • How many lines of code in a: • F-22 Raptor: • Average new Ford: 1.7 million 10 million
Computerized Measurement • Speed • Heading • Acceleration (lateral, longitudinal, vertical) • Position (from GPS) • Other diagnostics • Wipers on/off • Braking status • Tire pressure • Steering wheel angle • Headlights on/off • Turn signals on/off • Rain sensors • Stability control
Vehicle-to-Vehicle Communication: Not Sophisticated • Hi-tech vehicles • Low-tech communication with other vehicles • Brake lights • Turn signals • Horn • Flash headlights
Vehicle-to-Infrastructure Communication: Not Much Better • We want to know where vehicles are, what they’re doing • Many sensors already in the field to do this
Field Sensor Shortcomings • Limited data quality • Point detection, not continuous coverage • Difficult/expensive to repair = frequent downtime • Limited types of data • Aggregated speed, density, and volumes at a single point
Infrastructure-to-Vehicle • Difficult to communicate with the driver both in real-time and across a wide area
How it Works • Transmit data from the vehicle • Captured from GPS, accelerometers, magnetometers, or in-vehicle sensors • Transmit to other vehicles or roadside equipment • Cellular, Bluetooth, WiMAX, Wi-Fi, DSRC
Potential of Connected Vehicles • Three ways to connect: • Vehicle-to-vehicle: • Electronic brake lights • Crash avoidance • Vehicle-to-infrastructure: • Incident detection • Weather/ice detection • Infrastructure-to-vehicle • Broadcast traffic signal timing • Dynamic re-routing
Similarity to Other Safety Systems • Similar to radar- and laser-based safety systems, but much cheaper Adaptive Cruise Control Google Self-Driving Car
Connected Vehicles Today • Real-time speed data from cell phones
Research • VDOT is the lead state in the Cooperative Transportation Systems Pooled Fund Study • Traffic signal control • Broadcasting traffic signal timing to approaching vehicles • Potential of aftermarket add-on devices • Standardization • Pavement maintenance
Connected Vehicle Test Bed • University Transportation Centers grant for two small-scale field deployments of these technologies • Will use combination of cellular and Dedicated Short-Range Communications (DSRC) • Low latency, high bandwidth • Allows for most powerful safety and mobility applications
Connected Vehicle Test Bed • Partners: • VDOT • Virginia Tech • University of Virginia • Morgan State • Nissan and Volvo (advisory roles) • Available to other universities to test projects
Connected Vehicle Testbed • Virginia Tech Smart Road • 7 RSUs • Northern VA • 48 installed RSUs • 2 portable RSUs
Roadside Units I-495 I-66 US-29 Gallows Rd US-50
On Board Equipment • System offers Road Scout (Lane Detection), MASK (Head Tracker) and epoch detection • Data is captured over the vehicle network (CAN) • Parametric Data • Accel X,Y,Z • Gyro X,Y,Z • GPS Speed and Position • Network speed • Turn signal • Brake • Accelerator position • 200 Aftermarket Safety Devices are being developed • 10 instrumented cars • 4 sedans (GM brand) • 2 SUVs (GM brand) • 4 motorcycles • 2 instrumented heavy vehicles • Semi-truck • Motorcoach
Connected Vehicle Research Projects • 19 projects have been funded that focus on freeway and arterial applications: • Adaptive Stop/Yield • Adaptive Lighting • Intersection Management Using Speed Adaptation • Eco-Speed Control • Awareness System for Roadway Workers • Emergency V2V Communication • Freeway Merge Management • Infrastructure Safety Assessment • Safety and Congestion Issues Related to Public Transportation • Connected Motorcycle Crash Warning • Connected Motorcycle System Performance • Smartphone App Reducing Motorcycle and Bicycle Crashes • CV Freeway Speed Harmonization Systems • Reducing School Bus Conflicts through CVI • NextGen Transit Signal Priority with CVI • Smartphone DMS Application • Willingness to Pay and User Acceptance • Increasing Benefits at Low Penetration Rates
Background • Rollout of connected vehicles will not be instantaneous 16 years between kickoff and 80% Projected rollout of on-board equipment in US Fleet (Volpe, 2008)
Connected Vehicle Applications • Lots of connected vehicle mobility applications in development • Most of these applications need at least 25% of vehicles to be “connected” to see benefits • Higher percentages = more benefit
What it Means • Problem – Mobile sensors and connected vehicle data are not constant or ubiquitous. There are gaps. • Solution – “Location Estimation” • Behavior of equipped vehicles may suggest location of unequipped vehicles. Assumed Location of Unequipped Vehicle Equipped Vehicles
Methodology • How to estimate vehicle locations • Depends on unexpected behavior of equipped vehicles – indicates an unequipped vehicle ahead • What is “unexpected”? • Car-following model
Algorithm • Vehicles assumed to follow Wiedemann car-following model • Widely accepted, basis for VISSIM • A deviation from expected acceleration indicates an unequipped vehicle ahead Headway = 97 feet Vehicle B Vehicle C Vehicle A Inserted Vehicle (Estimate) Speed = 29 mph Acceleration = 0 Speed = 45 mph Acceleration = 0 ft/s2 Speed = 30 mph Acceleration = -4 ft/s2 Expected Accel = 7 ft/s2 Unexpected Behavior
Testing • Using NGSIM datasets as ground truth • 30-minutes of individual vehicle movements • ¼ mile segment of I-80 in Emeryville, CA • Designate some vehicles as “unequipped” and remove from data set
Densities Along I-80 at 25% Market Penetration Actual Densities (Sampled and Observed Vehicles) Distance (1/4 mile total) Estimated Densities (Sampled and Estimated Vehicles) Distance (1/4 mile total) Time (s)
Summary • Connected vehicles is important, innovative, and evolving • VCTIR/VDOT is committed to being at the forefront • Ensure that connected vehicles will meet the needs of Virginia
For more information:Noah Goodallnoah.goodall@vdot.virginia.gov