I'm currently working on designing an incandescent traffic light system and could use some guidance on extending and optimizing my design. Initially, I've successfully implemented the required specifications for a single lamp. Now, I'm looking to scale up the design to accommodate three traffic lamps in a cost-effective and efficient manner.

Current Progress:

For a single lamp, I've developed the following block diagram and corresponding schematic. Simulation results indicate satisfactory functionality. Here are the details:

Expansion Plan:

My plan is to extend this design to incorporate three lamps, preferably in a parallel configuration. However, I have concerns about potential synchronization issues with the 555 timers, leading to simultaneous illumination of multiple lamps.

Key Components:

The timing of the lamps is controlled by 555 timers, as illustrated in the attached figure. Additionally, a daylight detector is employed to switch between two brightness levels, facilitated by a relay/SPDT setup.

Seeking Advice:

Optimization Tips: I would appreciate any suggestions on optimizing the design for three lamps while maintaining efficiency and cost-effectiveness.

Synchronization Concerns: How can I ensure that the 555 timers remain synchronized to prevent overlapping lamp activation? Additionally I want each 555 timer to switch on the mains for its corresponding lamp via a relay.

Safety Considerations: As I haven't conducted physical testing yet, are there any potential safety hazards I should be aware of with this circuitry?

I'm open to any insights, tips, or recommendations that could help improve and refine my design. Thank you in advance for your assistance!