Multi-Stage Vision Inspection System

The customer required a comprehensive quality control solution for a product passing through multiple production stations, each demanding a different type of vision inspection.

The goal was to ensure 100% inspection coverage – from pallet verification at the infeed, through external defect detection, to internal inspection of complex product geometries – without extending the production cycle time.

The key technical challenges included:

• Precise inspection of WT pallets, including quantity verification, diameter measurement, detection of damage or contamination, and cleanliness control
• Detection of structural and surface defects in hard-to-reach internal areas, such as deep cavities and internal features
• Synchronization of line-scan cameras and illumination modules with dual servo drive systems, enabling reliable inspection “on the move”
• High throughput requirements:
  • 115 products per cycle
  • Up to 460 internal and external surface measurements per product
  • During a 17.8-second tray inspection cycle, the system performs 460 individual part inspections.
• Challenging optical conditions, including cylindrical components causing the tunnel effect

We designed and implemented a multi-stage vision inspection architecture, tailored to the functional role of each station in the production line.

The solution included:

• Dedicated inspection concepts for infeed pallet verification, external inspection, internal inspection, and unloading verification
• Combination of line-scan and area-scan cameras, selected based on inspection task and geometry
• Customized optics and lighting solutions optimized for each inspection zone
• Tight synchronization between vision systems, motion axes, and servo drives
• Full integration with traceability systems and MES, enabling real-time data availability and process monitoring

The system was designed to maintain inspection stability and repeatability, while preserving the required production dynamics.

During validation, the system demonstrated:

• Stable and repeatable inspection across all stations
• Reliable defect detection for both external and internal product features
• Accurate inspection “on the move” through synchronized motion and image acquisition
• Consistent performance under difficult optical conditions
• Full compliance with throughput and cycle time requirements

The implemented solution enabled:

• Full quality control across the entire production process
• Early detection of defects before downstream operations
• Automated verification of pallets and products at multiple stages

• Elimination of pallet-related defects and handling errors
• Reduced customer complaints, thanks to unloading inspection and early defect detection
• Faster inspection without extending the production cycle time
• Improved process stability and repeatability
• Higher overall line efficiency through automation and real-time quality control

This case study demonstrates that effective vision inspection is not a single station, but a consistently designed system spanning the entire production line. By combining tailored inspection concepts, synchronized motion, and high-performance vision technology, we delivered a robust, scalable quality control solution for demanding industrial applications.

Where inspection is challenging, we build stable and repeatable processes that support both quality and productivity.