1. FACULTY OF ENGINEERING
DEPARTMENT OF CIVIL AND STRUCTURAL
ENGINEERING
KKKA 6424
INTELLIGENT URBAN TRAFFIC CONTROL SYSTEM
Prof. Dr. Riza Atiq Abdullah O.K. Rahmat
ASSIGNMENT (1)
PREPARED BY:
1- HAIDER FARHAN P65405
2- MUSTAFA TALIB P60915
3-- SAHAR ABD ALI P65295
1

2. Introduction
Traffic lights
Traffic lights, also known as traffic signals, traffic lamps, signal
lights, robots and semaphores. Aresignaling devices positioned at or near road
intersections, pedestrian crossings and other locations to control competing flows of
traffic. Traffic lights were first installed in 1868 in London, United, now used in almost
every city of the world. Traffic lights alternate the right of way accorded to road users by
displaying lights of a standard color (red, yellow/amber, and green) following a
universal color code (and a precise sequence to enable comprehension by those who
are color blind).
In the typical sequence of color phases:
 Illumination of the green light allows traffic to proceed in the direction denoted, if it
is safe to do so
 Illumination of the yellow/amber light denoting prepare to stop short of the
intersection, if it is safe to do so
 Illumination of the red signal prohibits any traffic from proceeding
Usually, the red light contains some orange in its hue, and the green light contains some
blue, said to be for the benefit of people with red-green color blindness
Traffic signal is one of the more familiar types of intersection control. Using either a
fixed or adaptive schedule, traffic signals allow certain parts of the intersection to move
while forcing other parts to wait, delivering instructions to drivers through a set of
colorful lights (generally, of the standard red-yellow (amber)-green format). Some
purposes of traffic signals are to (1) improve overall safety, (2) decrease average travel
time through an intersection, and (3) equalize the quality of services for all or most traffic
streams. Traffic signals provide orderly movement of intersection traffic, have the ability
to be flexible for changes in traffic flow, and can assign priority treatment to certain
movements or vehicles, such as emergency services. However, they may increase delay
2

3. during the off-peak period and increase the probability of certain accidents, such as rear-
end collisions. Additionally, when improperly configured, driver irritation can become
an issue. Traffic signals are generally a well-accepted form of traffic control for busy
intersections and continue to be deployed. Other intersection control strategies include
signs (stop and yield) and roundabouts. Intersections with high volumes may be grade
separated.
Single aspects
The simplest traffic light comprises either a single or a pair of colored aspects that warns
any user of the shared right of way of a possible conflict or danger.
Flashing Red: Treat as a stop sign. Also can signal the road is closed.
Flashing Yellow: Caution, crossing or road hazard ahead
Flashing Green: Varies among jurisdiction; can give permission to go straight as well as
make a left turn in front of opposing traffic (which is held by a steady red light), or can
indicate the end of a green cycle before the light changes to a solid yellow.
3

4. Case study
Our team which consists of three engineers selected a series of intersection of three,
these three intersections are located on the road which link between Bangi (UKM),
Kajang, Sepakat, and the highway lead to KL as shown in the figure below.
Each one of these intersections are consist of three legs (three phases) and all phases
have two lanes in each intersection.
As a work team after selecting these intersections we conducted the traffic count
survey for one hour for each intersection, and we found that the cycle time of traffic
light for each intersection is (120seconds),(160 sec ),and (180 sec ) ,respectively,and
the all red for each approach ( 2 seconds ), and amber for each approach ( 3 seconds
).
4

5. 5

6. Intersection-1-
This is the first intersection linking Kajang, Babgi, and (UKM) as shown in the
figure below.
6

7. DATA OF INTERSECTION: 1
Passenger Car Unit Data traffic for one hour
Traffic Flows in KAJANG UKM BANGI
15 Min
Phase -1- Phase -2- Phase -3-
Cars/Van 755 846 361
Lori < 5 ton 42 118 37
Lori > 5 ton 13 4 5
Motorcycle 322 215 137
Bus 10 14 5
Mini Bus 12 17 10
so we need the table below
Bil Vehicle Passenger Car Unit
1 Car / van / jeep / mpv 1
2 Lorry < 5 ton 1.75
3 Lorry > 5 ton 2.25
4 Trailer 3
5 Mini Bus 2.5
6 Bus 2.75
7 Motorcycle 0.35
7

8. Phase Traffic Flows in 1 hour Total
Car Lorry<5ton Lorry>5ton Trailer Mini Bus M/cycle (pcu/hr)
Bus
1 755 42 13 0 12 10 322 1027
2 846 118 4 0 17 14 215 1216
3 361 37 5 0 10 5 137 524
PCU 1 1.75 2.25 3 2.5 2.75 0.35
UNIT
Phase Number of Saturation Saturation Actual Flow / Green
Lanes Flow per Flow Flows Saturation Time
Lane (pcu/hr) (pcu/hr) Flow Split
(pcu/hr) Ration
1 2 1800 3600 1027 0.33 0.44
2 2 1800 3600 1216 0.28 0.37
3 2 1800 3600 524 0.14 0.18
Total = 0.75=Y
L= 3 *(2+3) = 15 sec
Cycle time (C0 ) = 1.5 L + 5 / 1- Y = 1.5*(15)+5 / 1-0.75=110 sec
Effective green time = 110 – 15 = 95 sec
Phase -1- green time =95* 0.44 =41.8 =42 sec
Phase-2- green time =95*0.37 = 35.15 =36 sec
Phase-3-green time =95*0.18 = 17.1 = 18 sec
Total of green time = 42+36+18 = 96 sec
Total of amber & all red time =3 * (2+3) = 15 sec
Cycle time = 96 + 15 = 111 sec
8

9. Intersection-2-
The second intersection links Kajang, UKM, and Sepakat as shown in the figure
below.
9

10. DATA OF INTERSECTION: 2
Traffic Flows in KAJANG Ukm SEPAKAT
15 Min
Phase-1- Phase-2- Phase-3-
Cars/Van 808 918 338
Lori < 5 ton 46 135 46
Lori > 5 ton 17 5 11
Motorcycle 351 238 117
Bus 11 14 1
Mini Bus 14 20 4
Bil Vehicle Passenger Car Unit
1 Car / van / jeep / mpv 1
2 Lorry < 5 ton 1.75
3 Lorry > 5 ton 2.25
4 Trailer 3
5 Mini Bus 2.5
6 Bus 2.75
7 Motorcycle 0.35
11

11. Phase Traffic Flows in 1 hour Total
Car Lorry<5ton Lorry>5ton Trailer Mini Bus M/cycle (pcu/hr)
Bus
1 808 46 17 0 14 11 351 1115
2 918 135 5 0 20 14 238 1336
3 338 46 11 0 4 1 117 498
PCU 1 1.75 2.25 3 2.5 2.75 0.35
UNIT
Phase Number of Saturation Saturation Actual Flow / Green
Lanes Flow per Flow Flows Saturation Time Split
Lane (pcu/hr) (pcu/hr) Flow
(pcu/hr) Ration
1 2 1800 3600 1115 0.31 0.37
2 2 1800 3600 1336 0.37 0.45
3 2 1800 3600 498 0.14 0.17
Total = 0.82=Y
L = 3 * (2+3) = 15 sec
Cycle time (C0)=1.5L+5 /1-Y=1.5*15+5/1-0.82=155 sec
Effective green time = 155- 15 = 140 sec
Phase-1- green time =140* 0.37 =51.8 =52 sec
Phase-2- green time=140 *0.45 = 63sec
Phase-3-green time=140 *0.17=23.8 = 24 sec
Total of green time = 52+63+24 = 139 sec
Total of amber & all red = 3*(2+3) =15 sec
Cycle time = 139 +15 = 154 sec
11

12. Intersection-3-
This is the third intersection which links Kajang, UKM, and the highway as
shown in the figure below.
12

13. DATA OF INTERSECTION: 3
Traffic Flows in KAJANG Ukm HIGHWAY
15 Min
Phase-1- Phase-2- Phase-3-
Cars/Van 768 956 585
Lori < 5 ton 42 137 24
Lori > 5 ton 11 5 9
Motorcycle 333 258 34
Bus 11 14 3
Mini Bus 14 22 0
Bil Vehicle Passenger Car Unit
1 Car / van / jeep / mpv 1
2 Lorry < 5 ton 1.75
3 Lorry > 5 ton 2.25
4 Trailer 3
5 Mini Bus 2.5
6 Bus 2.75
7 Motorcycle 0.35
13

14. Phase Traffic Flows in 1 hour Total
Car Lorry<5ton Lorry>5ton Trailer Mini Bus M/cycle (pcu/hr)
Bus
1 768 42 11 0 16 12 333 1056
2 940 134 4 0 22 14 205 1348
3 585 24 9 0 0 3 34 667
PCU 1 1.75 2.25 3 2.5 2.75 0.35
UNIT
Phase Number of Saturation Saturation Actual Flow / Green
Lanes Flow per Flow Flows Saturation Time
Lane (pcu/hr) (pcu/hr) Flow Split
(pcu/hr) Ration
1 2 1800 3600 1056 0.29 0.34
2 2 1800 3600 1348 0.37 0.44
3 2 1800 3600 667 0.18 0.21
Total = 0.84= Y
L = 3 * (2+3) = 15 sec
Cycle time (C0) = 1.5L+5/1-Y=1.5*15+5/1-0.84=175
Effective green time =175 – 15 = 160 sec
Phase-1- green time = 160 * 0.34=54.4 =55 sec
Phase-2- green time = 160 * 0.44 =70.4 = 71 sec
Phase-3- green time = 160 * 0.21 =33.6 = 34 sec
Total time green = 55 + 71 + 34 = 160 sec
Total of amber& all red =3 *(2+3) =15 sec
Cycle time = 160 + 15 = 175 sec
14

15. Summary of results for cycle time ( C₀ ) and effective green time
( Ge)
Intersection Cycle time C₀ (sec) Effective Green time Ge (sec)
1 111 95
2 154 140
3 175 160
Calculation of cycle time:
After calculation of cycle time with Webster method, the highest cycle
time was for intersection 3 and it was equal to175 seconds. So adjust all
intersection using Cycle Time 175 second
phase Green
Intersection 1: time
Cycle time = 175 sec 1 71
Total of amber and all red time = (3+2) x3=15 sec 2 60
Total green time = 175-15=160sec 29
3
Phase 1 green time = 160* 0.44=70.4sec =71 sec
total 160
Phase 2 green time =160 *0.37=59.2sec=60sec
Phase 3 green time = 160*0.18=28.8sec=29sec
Intersection 2:
Cycle time = 175 sec
Total of amber and all red time = (3+2) x3= 15sec phase Green
Total green time = 175-15 =160sec time
Phase 1 green time =160*0.37=59.2sec=60sec 1 60
Phase 2 green time =160*0.45= 72sec 2 72
Phase 3 green time = 160*0.17=27.2sec =28sec 3 28
total 160
15

16. Intersection 3:
Cycle time =175 sec
Total of amber and all red time = (3+2) x3=15 sec
Total green time = 175-15= 160 sec phase Green
time
Phase 1 green time = 55sec 1 55
Phase 2 green time = 71sec 2 71
Phase 3 green time = 34 sec 3 34
total 160
Calculation of offset time :
Offset time : L/S - ( Qh+ loss)
Where
Q = Number of vehicles queued per lane, vehicle.
h = Discharge Headway of queued vehicle in seconds/vehicle.
Typical value of h is 2 seconds / vehicle.
S = Average Speed in metre in second
L = Distance between intersectios in metre
Loss1 = Loss Time associated with vehicles starting from rest at the
first downstream signal (2 seconds can be used as a default).
1-offset1
S= 10 m/s
L1= 1600 m
Q1= 12 veh
h=2 sec per veh
loss =2 sec
Offset1 =1600/10-(12x2+2) =134sec RELATIVE OFFSET= 134 , ABSOLUTE OFFSET=134
OFFSET===
16

17. 2-offset2
S= 10 m/s
L2= 250m
Q2= 14veh
h=2 sec per veh
loss =2 sec
Offset 2 =250/10-(14x2+2) =-5sec RELATIVE OFFSET =-5, ABSOLUTE OFFSET =129
3-Offset3= 0
17

18. 14cars 12cars
3 2 1
ntersection1
OFFSET=129
18

19. phase Green phase Green phase Green
time time time
1 55 1 60 1 71
2 71 2 72 2 60
3 34 3 28 3 29
total 160 total 160 total 160
Offset3 0 Offset2 -5 Offset1 134
19