Presentation on Adaptive traffic Systems

1
Presentation on Adaptive traffic Systems

• Brendan OBrien
• Head of Technical Services
• Dublin City Council

2
Adaptive Traffic Control in Dublin

• Sydney Co-ordinated Adaptive Traffic system
• SCATS first installed on 32 sites in 1989
• SCATS 6. 4 now installed on 400 out of 650 sites
• Also installed in Dun Laoghaire and Waterford
  city
• Owned and developed by the RTA NSW
• One of only two Adaptive traffic systems to have
  a world wide base
• 12,000 sites on SCATS world wide including Hong
  Kong, Mexico city, Oakland and Tehran

3
CYCLE TIME

• The total time to complete one cycle of all the
  stages
• Range 20 - 190 seconds

Typical range 40 - 160 seconds In City Council
40-120 Seconds
4
STAGE TIME (SPLIT)

• The percentage of the cycle time
• allocated to each stage

Stage A 55 Stage B 20 Stage C 25
5
OFFSETS

• Offset defines the start of a nominated stage at
  one intersection relative to the start of a
  nominated stage at another intersection.

Offset
Defined by LP 10,15d120 or PP data 10,15d.
End of D Phase intersection 120
With respect to Master SS
6
How to Control Traffic ?
Signal Groups (SGs)
controller
7
8
2
1
3
7
How to Control Traffic ?
We may group these into 3 stages
controller
Stage A
7
1
8
How to Control Traffic ?
controller
Stage B
3
9
How to Control Traffic ?
controller
Stage C
2
8
10
Dublin System
Workstations
SCMS SERVER

LAN
Dassnet link to Waterford Dun Laoghaire
Fingal South Dublin
Region
CCity
Local Controller
Local Controller
Local Controller
Local Controller
Current Capacity 668 sites