Seam Tracking with Vision and Through-Arc

Even perfect programs fail when parts vary. That’s why modern welding cells rely on adaptive seam tracking — using vision or through-arc sensing to guide the robot in real time.

1. Vision-Based Tracking

Laser profilometers or cameras detect joint geometry before each weld. The system dynamically shifts the path to stay within ±0.2 mm of the seam, even with part tolerances.

2. Through-Arc Sensing

Current and voltage variations reveal lateral deviation during welding. Through-arc control is ideal for MIG and TIG but requires clean signal processing and arc stability.

3. Hybrid Tracking

Combining both methods — vision for pre-scan and through-arc for dynamic correction — provides the most robust solution in variable production environments.

Example

A heavy-equipment OEM integrated through-arc seam tracking on 6-axis robots. Rework fell by 35%, and welding speed increased 18%.

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Conclusion

Adaptive seam tracking converts static programs into intelligent weld paths. Whether using vision or through-arc sensing, consistency improves — even when parts don’t.