Abstract: In some examples, an autonomous robotic welding system comprises a workspace including a part having a seam, a sensor configured to capture multiple images within the workspace, a robot configured to lay weld along the seam, and a controller. The controller is configured to identify the seam on the part in the workspace based on the multiple images, plan a path for the robot to follow when welding the seam, the path including multiple different configurations of the robot, and instruct the robot to weld the seam according to the planned path.

Abstract: A snow barrier for a roof having modular components including brackets that slidingly interfit into rails that extend up and down the slope of the roof. The brackets may be rotated to provide fences of differing heights. A corrugated fence is easily installed by reason of a self-positioning, hooked, upper flange formed along the upper edge of the corrugated fence. The corrugated fence may be modular, being built-up of smaller, corrugated strips. Pads may replace the rails in supporting the brackets or the brackets may be fastened directly to the roof.