Transcript PowerPoint Template - University of Maryland, College Park

Integrated Variable
Speed Limit Control to
Minimize Recurrent
Highway Congestions
Maryland State Highway
Administration
Traffic Safety and Operations Lab
Dept. of Civil and Environmental Engineering
University of Maryland, College Park
What is Variable Speed Limit (VSL)?
 A Variable Speed Limit (VSL) system:
 will change the speed limit dynamically
 based on the prevailing traffic conditions
2
University of Maryland Advanced
Transportation Technologies Day
Maryland State Highway
Administration
Traffic Safety and Operations Lab
Dept. of Civil and Environmental Engineering
University of Maryland, College Park
What does VSL include?
Traffic sensors
SPEED
45
3
University of Maryland Advanced
Transportation Technologies Day
Maryland State Highway
Administration
Traffic Safety and Operations Lab
Dept. of Civil and Environmental Engineering
University of Maryland, College Park
Why Use VSL?
Speed
(mph)
Upstream
Downstream
Speed
(mph)
Upstream
Direction of Travel
Downstream
Direction of Travel
 Smooth speed transition
 Mitigate traffic congestion
 Improve traffic safety
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University of Maryland Advanced
Transportation Technologies Day
Maryland State Highway
Administration
Traffic Safety and Operations Lab
Dept. of Civil and Environmental Engineering
University of Maryland, College Park
Field Demonstration Site
 MD-100
 Two-lane highway in each
direction
 Speed limit 55 MPH
 High accident frequency
(39 in 2008)
 High and dynamic traffic
demand during peak hours
 Rapid speed drop at
merging areas
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University of Maryland Advanced
Transportation Technologies Day
Location Map
N
Travel time:
Free flow: 180 sec
Congested: 600 sec
60mph
PROJECT LOCATION
Maryland State Highway
Administration
Traffic Safety and Operations Lab
Dept. of Civil and Environmental Engineering
University of Maryland, College Park
System Design
Location Map
N
SPEED
35
Control
2 pairs LPR •
cameras
• HD sensors
• Speed, volume (30 seconds)
2 VSL
• Display the control speeds
from algorithm
45
B
SPEED
SPEED
35
45
2 VMS
A
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University of Maryland Advanced
Transportation Technologies Day
Matching LPs to
calculate travel Times
4 Detectors
SPEED
A
Descriptions
B
Maryland State Highway
Administration
• Displays advisory messages
• Travel Time and/or
“reduced speed ahead”
Traffic Safety and Operations Lab
Dept. of Civil and Environmental Engineering
University of Maryland, College Park
Data Collection Plan
No Control
7
University of Maryland Advanced
Transportation Technologies Day
Maryland State Highway
Administration
Traffic Safety and Operations Lab
Dept. of Civil and Environmental Engineering
University of Maryland, College Park
Results (Speed for different locations)
Average Speed
Speed at
at Different
Different Locations
Locations
Average
Advantages
70
70
1. Reduce Accidents
2. Increase Speeds
3. Reduce Fuel Consumptions
Average
(MPH)
Speed (MPH)
Average Speed
60
60
50
50
No Control
No Control
TT Display Only
TT Display Only
VSL Only
40
40
30
30
VSL & TT Display
20
20
VSL Control
10
10
00
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MD 170
University of Maryland Advanced
Transportation Technologies Day
MD 713
MD 295
Coca Cola Dr.
Maryland State Highway
Administration
Traffic Safety and Operations Lab
Dept. of Civil and Environmental Engineering
University of Maryland, College Park
Results (Travel Time)
25%
600
Travel Time
No Control
Travel Time (Seconds)
500
No Control
TT Display Only
VSL Only
VSL & TT Display
400
300
VSL Only
200
VSL & TT
Display
100
0
16:30
TT Display
Only
16:45
17:00
17:15
17:30
17:45
18:00
18:15
18:30
Time
9
University of Maryland Advanced
Transportation Technologies Day
Maryland State Highway
Administration
Traffic Safety and Operations Lab
Dept. of Civil and Environmental Engineering
University of Maryland, College Park
Results (Travel time over different periods)
600
400
350
300
250
200
150
100
50
0
445
500
503
434
345
400
No Control
TT Display
300
VSL
VSL & TT
200
450
484
400
Travel Time (seconds)
Travel Time (seconds)
450
539
469
Travel Time (seconds)
500
350
300
407
388
385
401
297
250
No Control
200
TT Display
150
VSL
100
VSL & TT
No Control
TT Display
VSL
VSL & TT
50
100
The Peak-Period of 1 hour
0
The Peak-Period of 1 hour and a half
0
The Peak-Period of 30 Minutes
10
University of Maryland Advanced
Transportation Technologies Day
Maryland State Highway
Administration
Traffic Safety and Operations Lab
Dept. of Civil and Environmental Engineering
University of Maryland, College Park
Results (Throughput over different periods)
3848
3980
3941
3713
1883
1974
2045
2036
*The Peak-Period of 30 Minutes **The Peak-Period of 1 Hour
11
University of Maryland Advanced
Transportation Technologies Day
Maryland State Highway
Administration
Traffic Safety and Operations Lab
Dept. of Civil and Environmental Engineering
University of Maryland, College Park
Current Development
Source: FHWA
12
University of Maryland Advanced
Transportation Technologies Day
Maryland State Highway
Administration
Traffic Safety and Operations Lab
Dept. of Civil and Environmental Engineering
University of Maryland, College Park
Thanks & Questions?
More info: attap.umd.edu
13
University of Maryland Advanced
Transportation Technologies Day
Maryland State Highway
Administration
Traffic Safety and Operations Lab
Dept. of Civil and Environmental Engineering
University of Maryland, College Park