1. Using VISSIM to Evaluate BRT
Station Configurations and TSP
using ASC/3 Controllers
Scott Poska, P.E., PTOE
2013 PTV Users Group Meeting
October 2, 2013
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2. Outline
• Project Background
• Project Goals
• Study Methodology
• VISSIM Model
• ASC/3 Controller Module
• Station Configuration Evaluations & Results
• TSP Evaluation & Results
• Bus Following Video
• Project Conclusions
• VISSIM Lessons Learned
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3. Project Background
• Arterial Transitway
Corridors Study
completed April 2012
• Snelling Avenue top priority
• 1st BRT to be operated by
Metro Transit
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St. Paul
Minneapolis

4. 4
10 Miles
4 Cities
20 stations
2 LRT connections

5. BRT “Rapid Bus” Components
• Platform fare collection
• Half-mile station spacing
• Stops in travel lane
• 2 Doors
• Transit Signal Priority
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Illustration of a Rapid Bus
stop in the travel lane

6. Project Goals:
1. Evaluate mainline
traffic impact of
station locations
2. Assess potential
benefit of Transit
Signal Priority
Project Goals

7. Study Methodology
• VISSIM
• Scenarios
Modeled
• AM/PM
Peaks
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No. Scenario Name
1. Baseline
2. Rapid Bus Alpha
3. Rapid Bus Beta
4. Rapid Bus Refined
5. Rapid Bus Refined with TSP
Traffic Impact
TSP Benefit

8. VISSIM Model
• 10 miles long
• 34 signalized intersections
• Existing geometry & volumes
• Mix of existing/proposed signal timing
• Included 1 of 2 crossing LRT lines
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Co Rd B
Har Mar
Roselawn
Larpenteur
Hoyt
Midway
Hewitt
Thomas
Spruce Tree
St. Anthony
Concordia
Minnehaha
Co Rd B2 East RampsCo Rd B2 West Ramps
University
Marshall
Selby
Summit
Grand
St. Clair
Jefferson
Randolph
Highland
Ford

9. • Challenge
– Code & calibrate model of
this size!
• Solution
– Links/Connectors
– Split network elements up
– Use video from counts to
calibrate
• Model statistics
– 1200 links and connectors
– 5100 static routes
– ~30 min run time
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VISSIM Model

10. Econolite ASC/3 Controller Module
• ASC/3 controller module for all 34 signals
• Challenge
– No module operation documentation
• Solution:
– Interface identical to Virtual
Controller/Aries
– Interchangeable ASC/3 databases
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11. Rapid Bus Station
Configurations
• 3 station configurations
• 75% farside
• Occupancy varies
along route
• 10 min. headways
• 7-21 sec. dwell times
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Bumpout
Stop in Travel Lane;
Replace existing on-street
parking
Stop in Travel Lane Stop in Bus-Only Shoulder
Curbside

12. Station Configuration Evaluations
• Challenge
– What VISSIM Evaluation to
Measure Station Traffic
Impacts?
• Solution
– Test evaluations on small
network
• Node
• Link
• Travel Time
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Dwell Time (sec) 7 21 300
WBR (140 veh) 20.8 19.0 27.3
NBT (1535 veh) 18.6 19.0 48.3
EBL (110 veh) 40.7 43.5 39.0
Intersection 19.4 19.1 32.4
Adjacent Link 31.0 30.9 29.8
Upstrean Link 19.0 18.7 11.6
1305' Segment 45.1 46.9 76.2
Node Evaluation (sec/veh)
Link Evaluation (mph)
Travel Time Evaluation (sec)
Farside Station Evaluation Test

13. Results: Q1 - Traffic Impact
• MOEs:
– Travel Time
– Vehicle-delay /
Level of Service
• Baseline vs. Alpha
– AM Peak Hour
• No impact (<2 sec./veh.)
– PM Peak Hour
• University
• Hague
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0 20 40 60 80 100
Minnehaha
45th/46th
Woodlawn
Finn
Kenneth
Fairview
Highland
Randolph
St. Clair
Grand
Hague
University
Minnehaha
Hewitt
Larpenteur
Roselawn
Cty. B/Har Mar
4-Block Travel Time (sec.)
Baseline vs. Alpha Non-Rapid Bus Travel Time
Northbound - PM Peak Hour
Baseline
Alpha

14. Results: Q1 - Traffic Impact
• Alpha vs. Beta: NB University
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University
Spruce Tree
Snelling
Alpha
Beta
Scenario Platform Type
Rapid Bus Alpha
Farside + Bumpout
(stop in travel lane)
Rapid Bus Beta
Nearside + Curbside
(stop in right turn lane)
79.9
89.4
78.2
0
10
20
30
40
50
60
70
80
90
100
Northbound
4-BlockTravelTime(sec.)
Travel Time
Baseline
Alpha
Beta

15. TSP Assumptions
• Unconditional
• LRT vs. BRT:
first-come, first served
• Max green reduction:
– 25% of split or
– To phase minimum
• ASC/3 defaults:
– Early + extended
green
– No skipping/omitting
phases (incl. peds)
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16. TSP Setup in VISSIM
• Rapid Bus Detectors
• Placed 20 seconds in advance
• Placement adjusted for near-side stops
• ASC/3 mapper to assign TSP detector
numbers
• Locking detection issue
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17. Results: Q2 - TSP
• Network-wide:
– 10-14% travel
time reduction for
Rapid Bus
17
35 34
40
37
31 31
35
33
0
5
10
15
20
25
30
35
40
45
NB SB NB SB
AM PM
TravelTime(min.)
Rapid Bus Travel Time
No TSP
With TSP

18. Bus Following Video
• Client Requests
– “Bus Following” Videos
– “Play by Play” of
Signal Controller TSP Status
• Challenge
– “Bus Following” Keyframes
– Record ASC/3 Controller TSP status
• Solution
– Manually note times bus changes motion
– Manually note times of controller changes
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19. Project Conclusions
• No Station Impacts (AM Peak)
• 2 Stations with Impacts (PM Peak)
• Rapid Bus TSP Savings of 3-5 minutes (10-14%)
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20. VISSIM Lessons Learned
• Model Size
– Merge work frequently
– Vehicle Classes
– Text Editor for mass edits
• ASC/3 Controller Module
– TOD schedule & model time
– 4 digit filename
– Locking detection for TSP
• Evaluations
– Travel Time evaluation is simplest & most flexible
– Travel Time start/end locations
• Bus Following Video
• Note times and seed number
• No rewind!
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21. Acknowledgement
• Thank you to Katie Roth with
Metro Transit for managing
this successful project!
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22. Contact
Scott Poska, P.E., PTOE
SRF Consulting Group, Inc.
sposka@srfconsulting.com
www.srfconsulting.com
763-475-0010
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