Touch Sense & Groove Search

Built a wire-as-probe contact detection feature with a groove search workflow for automatically locating weld joints before welding begins. Integrated as a first-class step type in the executive interpreter using the ROS action-server pattern.

Implemented wire-as-probe contact detection using the welder's built-in touch sense hardware. The robot feeds welding wire at a controlled rate toward the workpiece; on electrical contact, the welder signals the robot to record the absolute position. The welding wire itself acts as the sensor — no additional hardware required.

Developed a groove-search workflow that probes both walls of grooved weld joints and computes the seam centerline from the contact points, providing the seam start position for the welding path. Edge cases like missed contacts are handled with configurable retries.

Integrated touch sensing as a first-class step type in the Python executive interpreter alongside move, weld, and gripper steps. The implementation follows the ROS action-server pattern — enabling the tablet UI to show real-time probe progress and allowing the operator to cancel mid-search. The probe result is stored in the program's variable space for use by subsequent weld steps.