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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
Introduction
Traffic lights
Traffic     lights, also   known       as traffic   signals,   traffic  lamps, signal
lights, robots and semaphores. Are signaling 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
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
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 (120 seconds),(160 sec ),and (180 sec )
,respectively, and the all red for each approach ( 2 seconds ), and amber for each
approach ( 3 seconds ).
Intersection-1-

This is the first intersection linking Kajang, Babgi, and (UKM) as shown in the
figure below.
DATA OF INTERSECTION: 1

assenger 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
Phase                         Traffic Flows in 1 hour                                Total

          Car       Lorry<5    Lorry>5     Trail     Mini    Bus       M/cycle      (pcu/hr)
                      ton        ton        er       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
Intersection-2-


The second intersection links Kajang, UKM, and Sepakat as shown in the
figure below.
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
Phase                           Traffic Flows in 1 hour                                    Total

           Car      Lorry<5to   Lorry>5to      Traile    Mini      Bus       M/cycle      (pcu/hr)
                        n           n            r       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 Time
          Lanes      Flow per Lane       Flow (pcu/hr)         Flows        Saturation      Split
                        (pcu/hr)                              (pcu/hr)     Flow 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 = 63 sec
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
Intersection-3-


 This is the third intersection which links Kajang, UKM, and the highway as
shown in the figure below.
DATA OF INTERSECTION: 3
Traffic Flows in 15         KAJANG                Ukm   HIGHWAY
        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
Phase                                 Traffic Flows in 1 hour                                 Total

             Car       Lorry<5to      Lorry>5to     Trailer   Mini       Bus    M/cycle       (pcu/hr)
                           n              n                   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 UNIT      1          1.75           2.25          3         2.5      2.75     0.35




Phase      Number of       Saturation         Saturation Flow    Actual Flows      Flow /       Green
             Lanes       Flow per Lane           (pcu/hr)          (pcu/hr)      Saturation   Time Split
                            (pcu/hr)                                            Flow 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
Summary of results for cycle time ( C₀ ) and effective green
                                                  time ( Ge)


         Intersection   Cycle time C₀ (sec )   Effective Green time Ge
                                                                  (sec)




        1                     111                     65


        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 seconds.

Intersection 1:                            Phase   Green time (sec )
Cycle time = 175 sec
Total of amber and all red time =
(3+2) x3=15 sec                             1             71
Total green time = 175-15=160sec
                                            2             60
Phase 1 green time = 160*
0.44=70.4sec =71 sec                        3             29
Phase 2 green time =160
                                           Total         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)   Phase   Green time (sec )

x3= 15sec
Total green time = 175-15 =160sec
Phase 1 green time
                                           1             60
=160*0.37=59.2sec=60sec
Phase 2 green time =160*0.45= 72sec
                                           2             72
Phase 3 green time = 160*0.17=27.2sec
=28sec
                                           3             28


                                          Total         160
Intersection 3:
Cycle time =175 sec
                              Phase   Green time (sec )
Total of amber and all red
time = (3+2) x3=15 sec
Total green time = 175-15=     1             55
160 sec
Phase 1 green time = 55sec     2             71

Phase 2 green time = 71sec     3             34
Phase 3 green time = 34 sec
                              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 meter in second
L = Distance between intersections in
meter
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
 phase Green time 1 55 2 71 3 34 total
 160
 RELATIVE OFFSET= 134 , ABSOLUTE
 OFFSET=134
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
traffic light setting
traffic light setting
traffic light setting

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  • 1. 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
  • 2. Introduction Traffic lights Traffic lights, also known as traffic signals, traffic lamps, signal lights, robots and semaphores. Are signaling 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
  • 3. 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
  • 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.
  • 5. 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 (120 seconds),(160 sec ),and (180 sec ) ,respectively, and the all red for each approach ( 2 seconds ), and amber for each approach ( 3 seconds ).
  • 6.
  • 7. Intersection-1- This is the first intersection linking Kajang, Babgi, and (UKM) as shown in the figure below.
  • 8.
  • 9. DATA OF INTERSECTION: 1 assenger 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
  • 10. Phase Traffic Flows in 1 hour Total Car Lorry<5 Lorry>5 Trail Mini Bus M/cycle (pcu/hr) ton ton er 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
  • 11. 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
  • 12. Intersection-2- The second intersection links Kajang, UKM, and Sepakat as shown in the figure below.
  • 13.
  • 14. 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
  • 15. Phase Traffic Flows in 1 hour Total Car Lorry<5to Lorry>5to Traile Mini Bus M/cycle (pcu/hr) n n r 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 Time Lanes Flow per Lane Flow (pcu/hr) Flows Saturation Split (pcu/hr) (pcu/hr) Flow 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
  • 16. 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 = 63 sec 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
  • 17. Intersection-3- This is the third intersection which links Kajang, UKM, and the highway as shown in the figure below.
  • 18.
  • 19. DATA OF INTERSECTION: 3 Traffic Flows in 15 KAJANG Ukm HIGHWAY 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
  • 20. Phase Traffic Flows in 1 hour Total Car Lorry<5to Lorry>5to Trailer Mini Bus M/cycle (pcu/hr) n n 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 UNIT 1 1.75 2.25 3 2.5 2.75 0.35 Phase Number of Saturation Saturation Flow Actual Flows Flow / Green Lanes Flow per Lane (pcu/hr) (pcu/hr) Saturation Time Split (pcu/hr) Flow 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
  • 21. 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
  • 22. Summary of results for cycle time ( C₀ ) and effective green time ( Ge) Intersection Cycle time C₀ (sec ) Effective Green time Ge (sec) 1 111 65 2 154 140 3 175 160
  • 23. 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 seconds. Intersection 1: Phase Green time (sec ) Cycle time = 175 sec Total of amber and all red time = (3+2) x3=15 sec 1 71 Total green time = 175-15=160sec 2 60 Phase 1 green time = 160* 0.44=70.4sec =71 sec 3 29 Phase 2 green time =160 Total 160 *0.37=59.2sec=60sec Phase 3 green time = 160*0.18=28.8sec=29sec
  • 24. Intersection 2: Cycle time = 175 sec Total of amber and all red time = (3+2) Phase Green time (sec ) x3= 15sec Total green time = 175-15 =160sec Phase 1 green time 1 60 =160*0.37=59.2sec=60sec Phase 2 green time =160*0.45= 72sec 2 72 Phase 3 green time = 160*0.17=27.2sec =28sec 3 28 Total 160
  • 25. Intersection 3: Cycle time =175 sec Phase Green time (sec ) Total of amber and all red time = (3+2) x3=15 sec Total green time = 175-15= 1 55 160 sec Phase 1 green time = 55sec 2 71 Phase 2 green time = 71sec 3 34 Phase 3 green time = 34 sec Total 160
  • 26. 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 meter in second L = Distance between intersections in meter Loss1 = Loss Time associated with vehicles starting from rest at the first downstream signal (2 seconds can be used as a default).
  • 27. -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 phase Green time 1 55 2 71 3 34 total 160 RELATIVE OFFSET= 134 , ABSOLUTE OFFSET=134 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