Design of Traffic Light System

Design of Traffic Light System Contents Task 1 Design Specification Design 1 Complete Block Diagram of the traffic light system State diagram Table Circuit simulation using Multisim software, Task 2 Timing Counter Task 3 Figure 13 (Main red and amber sub amber) Task 4 Remake design LIST IN Tab;e Table 1(State diagramme) Table 2(D type Flip Flop) Table 3(design cost) Table 4(compare table) List in Figure Figure 1: traffic lights system Figure 2(block diagrammed) Figure 3(Moore model) Figure 4 (main red and sub green for 10s) Figure 5 (Main amber and sub red and amber for 2s) Figure 6(main red and sub green for 10s) Figure 7 (Asynchronous counter for timing counter) Figure 8(The Design is 30s counter for main road in Asynchronous counter) Figure 9 (The Design is 20s counter for side road in Asynchronous counter) Figure 10 Main green and sub red Figure 11 (Main amber and sub red and amber) Figure 12 (Main red and sub green) Figure 13 (Main red and amber sub amber) Figure 14(remake design) Design Specification Design specification prepared for a single main and sub -road junction in rural area is given below The green light for the main road will be stay ON for 30s. The green light for the side road will be stay ON for 20s. The amber caution light will say ON for 5s between changes from green to red. Main road and side road timing countdown should display in a 7segment display. Sequence change of the traffic lights show in the Appendix I. The traffic light system for a single main road and sub road junction in a rural area. Complete Block Diagram of the traffic light system Figure 2(block diagrammed) The FSM description stands for Finite state machines. the Finite state machines are the most common controllers of machines. Its In the example Traffic light, the intersection of a main road with a side road is controlled by two traffic lights. FSM has three inputs (T1, T2 and T3) AND six outputs (Rm, Am, Gm, Rs, As and Gs) In here Rm is Red light for main road Am is Amber caution light for main road Gm is Green light for main road Rs is Red light for sub road As is Amber caution light for sub road Gs is green light for sub road T1 time is 30seconds T2 time is 20seconds T3 time is 5seconds Complete Moore model state diagram for traffic light system State diagram Table P.State N.State INPUT Outputs Gm Am Rm Gs As Rs 1 0 0 0 0 1 T1 0 1 0 0 1 1 T3 0 0 1 1 0 0 T2 0 1 1 0 1 0 T3 Table 1(State diagramme) State Assignment in Gray code Here using gray code for states State transection table Here using D type flip flops for design a circuit P.S Q1 Q0 N.S Q1+ Q0+ INPUT Gm Am Rm Gs As Rs 0 0 0 0 0 0 1 0 0 0 0 1 0 1 T1 0 1 0 1 0 1 0 1 0 1 0 0 1 1 1 1 T3 1 1 1 1 1 1 1 1 0 0 1 1 0 0 1 0 T2 1 0 1 0 1 0 1 0 0 1 1 0 1 0 0 0 T3 0 0 Table 2(D type Flip Flop) Simplified equations for the system. From Laws of Boolean Algebra ( The equations are, Circuit simulation using Multisim software, Figure 4 (main red and sub green for 10s) Figure 5 (Main amber and sub red and amber for 2s) Figure 6(main red and sub green for 10s) Timing Counter Figure 10 Main green and sub red Figure 11 (Main amber and sub red and amber) Figure 12 (Main red and sub green) Figure 13 (Main red and amber sub amber) Task 4 Item name quantity Price (Rs) 2 pin AND gate IC 5 120ÃÆ'-5=600 3 pin AND gate IC 2 120ÃÆ'-2=240 2 pin OR gate IC 1 40ÃÆ'-4=40 3 pin OR gate IC 1 40ÃÆ'-1=40 2 pin XOR gate IC 1 40ÃÆ'-1=40 Dual JK FF IC 10 100ÃÆ'-10=1000 Dual D FF IC 1 100ÃÆ'-1=100 DCD 7 Segment decoder IC 5 100ÃÆ'-5=500 7 Segment display 5 50ÃÆ'-5=250 NOT gate IC 2 40ÃÆ'-2=80 Red color LED 2 5ÃÆ'-2=10 Amber color LED 2 5ÃÆ'-2=10 Green color LED 2 5ÃÆ'-2=10 wires 20m 15ÃÆ'-20=300 Power adaptor 2 150ÃÆ'-2=300 Total 3420 Table 3(design cost) Remake design Figure 14(remake design) Compare the cost Item name Previous cost (Rs) New cost(Rs) 2 pin AND gate IC 1ÃÆ'-120 = 120 1ÃÆ'-120 = 120 3 pin AND gate IC 1ÃÆ'-120 = 120 0 XOR gate IC 1ÃÆ'- 40 = 40 0 D type FF IC 1ÃÆ'-100 = 100 1ÃÆ'-100 = 100 Decoder IC 0 1ÃÆ'-100 = 100 NOT gate IC 1ÃÆ'- 40 = 40 2ÃÆ'- 40 = 40 OR gate Ic 1ÃÆ'- 40 = 40 1ÃÆ'- 40 = 40 total 460 400 Table 4(compare table) In new design cost is less than old design Reference à ¯Ã†â€™Ã‹Å"à ¯Ã¢â€š ¬Ã‚  Mano M.M,Michael D.C. (2008).Digital Design.New Delhi:PHI. à ¯Ã†â€™Ã‹Å"à ¯Ã¢â€š ¬Ã‚  Floyd,L.(2011).Digital Fundamentals.10th ed.India:Pearson. p271- 287. à ¯Ã†â€™Ã‹Å"à ¯Ã¢â€š ¬Ã‚  http://www.topssrilanka.com/article24948-new-traffic-ligth-system-atbambalapitiya.html.Lasr à ¯Ã†â€™Ã‹Å"à ¯Ã¢â€š ¬Ã‚  http://www.sundayobserver.lk/2012/06/03/imp01.asp