What a Seam Tracking & Seam Finding Sensor Does
A seam tracking sensor and a seam finding sensor solve two related but different problems!!
A seam tracking sensor and a seam finding sensor solve two related but different problems, and this series handles both. The sensor projects a laser line across the joint and reads its 3D profile through an integrated camera, using laser triangulation to calculate the exact position, width, and depth of the seam. That data is passed to the host control unit, which communicates directly with the robot controller or PLC in real time. The distinction between tracking and finding comes down to timing and how the correction is applied.
Seam Tracking: Real-Time Correction While Welding
In tracking mode, the sensor scans just ahead of the torch while welding is in progress and continuously feeds joint position data to the robot controller. As the robot moves along its programmed path, it adjusts that path on the fly to follow the actual seam rather than the taught path. This matters because parts rarely sit exactly where they were taught: thermal distortion during welding, fixture wear, and normal part-to-part tolerance all shift the joint slightly from one workpiece to the next. Real-time tracking compensates for these shifts as they happen, which keeps weld bead placement consistent, reduces the rejection rate on parts with tolerance variation, and removes the need to slow the robot down "just in case" the joint has drifted.
Seam Finding: Locating the Joint Before Welding Starts
In finding mode, the sensor scans the joint before the arc or laser starts, locating the precise start point and overall path so the robot can correct its program before welding begins. This is the better approach when the main issue isn't deformation during welding but inconsistent part placement going into the cell — for example when parts come from a stamping or casting process with natural dimensional variation, or when fixtures introduce slight rotation or offset from one cycle to the next. Seam finding eliminates the manual re-teaching that would otherwise be needed every time a batch of parts doesn't sit exactly as expected, and it's commonly used together with tracking for a complete pre-weld-and-during-weld correction workflow.
Works With Your Existing Robot Cell
This series communicates with more than 40 robot and controller brands, including KUKA, FANUC, YASKAWA, ABB, Panasonic, Staubli, OTC, UR, and JAKA. If you're integrating into an existing cell rather than building a new one, the sensor is designed to be added without replacing your current robot or controller.
