CHALLENGE
The client needed to replace an outdated RS485 system with a modern Wi-Fi-based ticketing system. The challenge was to control entry gates using "No Touch" sensors and barcode tickets while keeping existing printers.
SOLUTION
- ESP32 PLCs programmed with Arduino IDE
- Local web server via HTTP
- Wi-Fi barcode readers + LCD screens
- Legacy printer reuse via serial-to-Wi-Fi bridge
- Fully open-source & modular solution
IMPLEMENTATION
- 3 months to full operation
- Resolved EMI issues using Industrial Shields hardware
- Wi-Fi signal improved with external antenna
- Offline/online time-stamp ticketing
RESULTS
- 80% ticket cost savings
- 24/7 autonomous system
- Reduced maintenance
- Centralized control with 1 PLC
- Reused existing equipment
