🚦 Two-Way Traffic System (Multisim Design)

📌 Overview

This project is a Digital Logic Design implementation of a two-way traffic signal control system using logic gates and D flip-flops in Multisim. The design simulates a traffic signal controlling two roads at an intersection, ensuring smooth traffic flow through alternating red, yellow, and green signals.

🎯 Objective

The goal is to design a traffic signal system using combinational logic circuits and flip-flops to regulate traffic flow efficiently at an intersection.

🛠️ Equipment & Software

• Multisim Software
• Logic Gates: NOT, XOR, NAND, AND gates
• Flip-Flops: D flip-flops (7474N)
• Traffic Light Indicators
• Switches & Power Sources

🔧 Design & Implementation

The traffic system follows a four-phase sequence:

1. Road 1 Green, Road 2 Red → Road 1 is open while Road 2 is stopped.
2. Road 1 Yellow, Road 2 Red → Warning before Road 1 stops.
3. Road 1 Red, Road 2 Green → Road 1 stops, Road 2 opens.
4. Road 1 Red, Road 2 Yellow → Warning before Road 2 stops.

Logic Expressions Used:

Boolean expressions were used to determine traffic light behavior:

• A̅ = A̅B + AB̅ = A ⊕ B
• B̅ = B̅t + A̅B̅ x̅y + AB̅xy̅
• Output Logic:
  • Red1 = A̅B̅, Yellow1 = A̅B, Green1 = A
  • Red2 = AB̅, Yellow2 = AB, Green2 = A̅

📌 Procedure in Multisim

1. Open Multisim and place components:
   • Logic gates (74LS04N, 74LS86N, 74LS00N, 74LS10N, 74LS08N)
   • Flip-flops (7474N)
   • Traffic light signals
2. Connect power sources (VCC, GND, Clock Voltage).
3. Configure switches for manual input.
4. Implement logic circuit wiring based on Boolean expressions.
5. Attach probes to traffic light signals for output verification.
6. Run the simulation to test traffic light transitions.

🔬 Observations

• The system successfully controls traffic flow as expected.
• Inputs trigger correct light transitions based on flip-flop states.
• Traffic lights function in a cyclic manner, ensuring smooth alternation between roads.

🏁 Conclusion

The two-way traffic system was successfully implemented using logic gates and flip-flops in Multisim. The system accurately followed the four-phase sequence, validating the Boolean expressions and logical design.

📂 Project Files Included:

• Multisim Design File (.ms12) – Full circuit schematic.
• Simulation Screenshots – Captures of the working model.
• Project Report (.pdf) – Detailed documentation.

🚀 Feel free to explore and modify the design! 😊