Abstract Scope |
A digital twin of commercial robotic welding systems can be developed using commercial computer aided modeling (CAM) software to enable automated path planning for welding, cladding, and additive manufacturing. Using the same CAM software, these robotic welding systems can be converted into hybrid systems by using high capacity tool changers and forced controlled spindle. These agile capabilities can be used to build large structures, additively manufacture features on structures, and finish features during a build. A National Shipbuilding Research Program (NSRP) project was completed to accelerate the transition and implementation of robotic arc DED AM. Multiple commercial robotic welding system were converted into DED test-bed systems. To advance large format capabilities, a multi-process robotic gantry system was developed and integrated for hybrid manufacturing with 11-axis of coordinated motion. This system incorporates a precision 60-kg robot and tool changer for both arc DED and high-speed spindle for feature finishing. For arc DED, the gantry carries two different gas metal arc (GMA) systems for either reciprocating wire feed or pulse metal transfer. For feature finishing, the spindle has the capability to change tools for drilling, burring, grinding, sanding and / or brushing. The system has a range of sensor to enable development of “lights-out” support processes and high productivity builds. The build volumes of the large-format robotic gantry DED system is 8’ high x 14’ wide x 30’ long and even larger pre-engineered systems are commercially available because of this project. A digital twin of the gantry was developed and evaluated for deposition with either the 3-axis gantry, the 6-axis robot, 9- axis of coordinated gantry & robot motion, and 11-axis with the 1-ton tilt/turn positioner. High quality builds that meet MIL-STD-2035 class 1 nondestructive testing requirements were demonstrated on stainless steel and used to build a large-format hollow propeller blade. |