That's a fantastic question! If I were designing a lights-out factory from scratch today, I'd definitely leave some legacy concepts behind while betting big on emerging technologies. Here's what I'd do:

First, I'd abandon:

• Rigid, fixed automation systems - The old-school approach where machines do one thing and can't adapt. Today's factories need flexibility to handle product variations and rapid changeovers.
• Isolated legacy systems - Those standalone PLCs and SCADA systems that don't talk to each other. In a lights-out factory, everything needs to be interconnected and data-driven.
• Manual quality inspection - Human eyes checking products is too slow and inconsistent for 24/7 autonomous operation.
• Scheduled maintenance - Waiting for equipment to fail or following fixed maintenance schedules just doesn't cut it when you're running without human oversight.

Now for the technologies I'd bet my career on:

• Digital Twins - This would be my foundation. A complete virtual replica of the factory that lets me simulate, optimize, and predict outcomes before implementing anything in the physical world. It's like having a crystal ball for manufacturing.
• Edge AI - Putting AI right on the factory floor where decisions need to happen in milliseconds. This enables real-time quality monitoring, predictive maintenance, and adaptive control without waiting for cloud processing.
• AI-powered robotics - Not just programmed robots, but systems that can learn, adapt, and handle unexpected situations autonomously.
• 5G-enabled IIoT - Ultra-reliable, low-latency connectivity that ties everything together, from sensors to robots to control systems.

The real magic happens when these technologies work together - digital twins creating the virtual playground, edge AI making split-second decisions on the factory floor, and AI systems continuously learning and optimizing the entire operation. It's about creating a factory that's not just automated, but truly intelligent and self-optimizing.