Traffic Control in a VII Environment - TRB Traffic Signal Systems ...

Traffic Control in a VII Environment Larry Head,University of Arizona Traffic Signal Systems Committee Workshop Vehicle Infrastructure Integration (VII) and Collaborative Intersection Collision Avoidance System (CICAS) TRB Annual Meeting – Washington, DC Sunday January 13, 13 2008 1

Assumptions • Vehicle V hi l IInfrastructure f t t Integration I t ti (VII) will ill support communication between Vehicles (with intelligence) and the Traffic Control Infrastructure (with intelligence) • Current Traffic Signal Control technologies are not sufficient to achieve the goals of improved safety and efficiency • New models, models methods methods, and technologies will be developed, deployed, and operated to meet these g goals - otherwise we are “missing g the boat” © 2008 K. Larry Head, Ph.D.

2008 TRB Traffic Signal Systems Committee Annual Meeting Workshop

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Today’s Traffic Signal Controller Features – How did we get here??? • “Why should I wait when • • • • •

there are no opposing vehicles?” “I want to safely walk across the street” “I want to progress though all of the intersections on the arterial.” “What do we do about the ttrain a crossing c oss g tthe e road?” oad “The Emergency Vehicles shouldn’t be delayed!” “Why y do you y stop p my y buses?”

© 2008 K. Larry Head, Ph.D.

Vehicle Actuated Control P d t i Pedestrian Intervals I t l Coordination Railroad Preemption EV Preemption Transit Priority


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New Controller Features in a VII Environment….. • “Warn me if a vehicle is going • • • • •

to violate a signal control” “Can the signal change to help prevent an accident? accident?” “How is the signal performing?” “Can Can you optimize signal timing in real-time?” “What if several buses arrive at the same time?” “I can’t always see the traffic signal (e.g. behind truck in left turn lane) © 2008 K. Larry Head, Ph.D.

Cooperative Intersection Collision Avoidance - CICAS

Vehicle Based Performance Measurement Adaptive/Optimal Signal Control Adaptive Priority Control In-vehicle Signing


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New Control Paradigms in a VII Environment….. • “Warn Warn me if another vehicle •

enters my safe (conflict) space” “Warn me if I enter another vehicles safe (conflict) space”

• “Why should I wait for the signal to change if there is a gap in opposing traffic?” traffic?

Predictive trajectory safety Warnings (Vehicle based)

Vehicle Based Shared Right-of-Way Control

me to avoid a collision”

Vehicle Safety Driver Assist

•

“Drive on the highway for me…….”

Autonomous Vehicle Control

•

Drive for me in congested congested, city “Drive traffic”

Complex Networked Control Systems

• “Maneuver (steer or accelerate)



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VII Architecture + Traffic Control Infrastructure Other communications WiFi WiFi, Cellular etcetera

GPS

Antenna

V-V

GPS

VEHICLES

Other vehicles

FIELD

Antenna

Driver

Onboard Equipment (OBE) Other communications

GPS

HMI interface

OBE

OBU

Applications processor

VII IPv6 Network VII Message Switch Registrations Subscriptions Operations Rules Management Maintenance

Vehicle services

RSU Provisioning server

Other Message Switches


HMI

Signal controller

Body chassis systems

Local safety processor

GPS Antenna

Roadside Equipment (RSE) RSU & GPS processor receiver

I/O Controller

Router

Significant Traffic Control In VII Environment Component

TOCs and other public sector users

VII network management applications Firewall

GSA Certification Authority (CA) Gateway to other communication systems

RSU’s DSRC antenna

DSRC

OEM/ISP applications

Map and differential corrections server

CENTERS

Note: Grayed boxes are peripheral and not part of the core VII architecture

OBE Provisioning server Content and services

EXTERNAL USERS


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VII – Information from the Intelligent Vehicle

Safety Systems Radar Collision Warning Intelligent Cruise Control Navigation Other Commercial Apps


• • • • • • • • •

ID: Location: (Long, Lat, Alt) S Speed: d 53 53.24 24 f fps Acceleration: -1.2 f/s^2 Class: Passenger Route: Next Left Status: Normal Link Travel Time: 63 63.04s 04s Path=(………..)


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Basics: Why Traffic Control? • Efficiency Shared use of infrastructure right-of-way in a way that does not result in unnecessary delay Characterize by • Actuated (state-of-the-practice today) • Adaptive (some deployments, not typical) • Optimizing (R&D)

• Safety Share use of infrastructure right-of-way in a way that does not result in accidents accidents, collisions collisions, or harm to property or person Characterize by • Structured (by controller structure - e.g. dual ring) • Aware (vehicles aware of signals and vehicle dynamics) • Active (cooperation between signals and vehicle controls) © 2008 K. Larry Head, Ph.D.


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Control for Safety and Efficiency Information Richness

Complex Networked Control Systems

Vehicle Control Vehicle Trajectories

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CICAS-V

Vehicle Dynamics

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Vehicle Performance

Today

Vehicle Based Safety

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3 3.5 EV Priority

Possible Early VII Application

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Detection

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Actuated Structured © 2008 K. Larry Head, Ph.D.

Adaptive

Optimizing

Aware

Active


Efficiency Safety 9

Detection and Actuation

Today

1

2

Movements Phases Detectors

Dual Ring, Ring 8-Phase 8 Phase Controller © 2008 K. Larry Head, Ph.D.


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Vehicle Performance Measures f Adaptive for Ad ti Control C t l •413256 •(106.23,52,23,2043.7) ( , , , ) • Delay = 3.4 sec • Travel Time = 61 sec • Path = (…………)

•65324 •(106.23,56,23,2043.1) • Delay D l = 17 17.3 3 sec • Travel Time = 132 sec • Path = (……………..)

Signal Delay Queueing Delay Travel Time Start up Loss Time Saturation Flow Turning Counts Dilemma Zone Events

•Unequipped •(106.23, 56.21, 2043.1) • Delay = 22.5 sec • Travel Time = unknown • Path = Unknown © 2008 K. Larry Head, Ph.D.


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Adaptive Control and Priority •

R81 = 42 Delay = 6 Seconds

t11

t31 + v31

t12

t11 + v11

t21 + v12

2

1

t12 + v12

t41

t22

t32 + v32

t +v t31

1 4

1 4

4

3

t12

2

1 2 5

t +v 2 2

2 2

t32

3

t42 4

Trade-off Trade off Performance Measures

t42 + v42

• • • •

t t51

5

t51 + v51

t =0

6

1 t61 + v16 t7

t61

t = 28

7

8

t71 + v71

t81

t81 + v81

t = 48

5

t52 + v52

6

t62

t62 + v62

t72

7

8

t72 + v72

Multi-Modal Delay

t81 + v82

t82

Time

Progression g • • •

• • © 2008 K. Larry Head, Ph.D.

Transit Passenger Vehicles Pedestrians Trucks Stops “Smoothness” Travel Time

Control Decisions with Quantified Performance Congestion Mitigation and Control


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Adaptive Control and Priority 3.5 EV Priorityy

• Intelligent I t lli tP Priority i it ffor Emergency Responders VII Communication of Request for Priority VII Signal Si l Status St t Returned to EV • Shows multiple requests t on different diff t approaches

Arizona E-VII Effort © 2008 K. Larry Head, Ph.D.


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CICAS

4 •65324 •(106.23,56,23,2043.1) • 53.24 53 24 f fps • -1.2 f/s^2 • Passenger • Next Left

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Vehicle Based S f t Safety •413256 •(106.23,52,23,2043.7) • 66.01 fps • +.024 + 024 f/ f/s^2 ^2 • Police • Thru

Analogous to Air Traffic Controller R d Display Radar Di l •Unequipped •(106.23, 56.21, 2043.1) •51.73 fps •-0.8 f/s^2 / •unknown •unknown © 2008 K. Larry Head, Ph.D.

Used to support Safetyy & Control 2008 TRB Traffic Signal Systems Committee Annual Meeting Workshop

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Safety Conflict Analysis • Models M d l tto predict di t

PET e c n ta s i D

crossing vehicle TTC

conflict point

projected arrival at conflict pt

MaxS and DeltaS

encroachment begin

actual arrival at conflict pt encroachment Initial Deceleration end Rate Vehicle begins braking

Through vehicle

t 1

t 2

t 3

t 4

t 5

measures of safety as inputs p to vehicle and signal control Time to Collision (TTC) Post Encroachment Time (PET) Maximum Speed (MaxS) Speed S d Diff Difference (D (Delta lt S)

Tim e

Source: Gettman, Head, “Surrogate Safety Measures From Traffic Simulation Models”, FHWA Report FHWA-RD-03-050



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CICAS Counter Measures •65324 •(106.23,56,23,2043.1) • 53.24 fps • -1.2 f/s^2 • Passenger • Next Left

•413256 •(106.23,52,23,2043.7) • 66.01 fps • +.024 f/s^2 • Police • Thru

•Unequipped •(106.23, 56.21, 2043.1) •51.73 fps •-0.8 f/s^2 •unknown •unknown

In-Vehicle Counter Measures • Heads-Up p Display p y • Audible Warning

Safety Conflict Measures © 2008 K. Larry Head, Ph.D.

Infrastructure Counter Measures • Active Signs • Traffic Signal Control Modifications •Red Extension (?) •Early Termination (?)

•Automatic Braking •Steering Maneuvers to Reduce Collision Impact


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In-vehicle Signing • Today T d we have h iin-vehicle hi l navigation systems GPS Location Vehicle Status Vehicle Routing



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In-vehicle Signing • Vehicle Driver Interface Heads Up Display Control System Status (*)

Speed Speed 35 Limit

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• Phase near end of extension interval

Roadway Segment Speed • Progression Speed

Warnings • Unusual Vehicle Behavior


Warning: Navigate: Left Turn Behavior Traffic Controller must publish Signal State Infrastructure publish Warnings and Speed


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Complex Networked Control 7 Systems 6

• Recent efforts and developments in Control Systems Theory: S. Martinez, J. Cortes, and F Bullo, F. Bullo “Motion Motion Coordination with Distributed Information”, IEEE Control Systems Magazine, August 2007 From IEEE Control Systems Magazine Feb. 2004 © 2008 K. Larry Head, Ph.D.


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VII - Traffic Signal Control •

Integration of Vehicle Data into Control Algorithms

Vehicle State Estimation • • •

•

Trajectory Performance F i off traditional Fusion t diti l and d VII data d t

Inputs to Control

Priority Request Generation Vehicle Class Priority (Transit, Snowplows, Trucks, etc.) CICAS (Safety) ( y)

Control State Information Broadcast to VII

Active Phase, Interval, and End Times Outputs from Control Opportunistic Service Intervals P di t d C Predicted Conflicts fli t Trajectory controls (e.g. max acceleration, steering)



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Conclusions • Traffic T ffi Si Signall System S t improvements i t will ill iinclude l d both infrastructure and vehicle controls • We have opportunities for immediate impacts of integrated technologies with Vehicle Performance Measures Adaptive and Optimizing Control

• We need to start conducting research on how traffic control can benefit from developments in Complex Networked Control Systems - this is likelyy where the real solution lies © 2008 K. Larry Head, Ph.D.


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Questions? Two quotations from Driving Questions: Developing a National Transportation Vision, Joseph M. Giglio, The Hudson Institute, 2007.

“Today’s “T d ’ problems bl can’t ’t b be solved l db by thi thinking ki tto way we thought when we created them.” Albert Einstein

“..[we need to] find 21-st-century solutions for 21-st-century transportation problems. … We can’t assume that the methods of the p past will work for the future. Instead we are going to have to recognize that our transportation challenges have changed dramatically in the forty years since this department came into being, and so must our approaches.” Mary Peters Peters, Secretary of Transportation Transportation, 2006 © 2008 K. Larry Head, Ph.D.


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