Project Outcomes Report:
NSF PII award #0849008
October 15, 2012
James W. Beard, PI
“Developing a Mobile, Robotic Welding System”
Many industries such as large shipbuilding and site-based fabrication and construction do not lend themselves to traditional assembly line robotic systems. Large military ships, for example, tend to be unique with each successive ship manufactured having different characteristics. The size and scale of a typical ship combined with the high costs associated with dry-docks or real-estate immediately adjacent to the launch location has led toward a common manufacturing technique in which the structural components of the ship are assembled in multiple locations with only the final assembly occurring in the most expensive location. We call these “unstructured environments” because the building process is not regular (i.e., is not highly dimensionalized). Robotic systems in these environments must be mobile, flexible and adaptable. This creates a unique set of challenges that this project has addressed.
Mobile robotics (robotic systems capable of navigating through the environment to perform motion control tasks) provides new opportunities to improve worker productivity in unstructured environments. Robotic Technologies of Tennessee (RTT) and its University partner, Tennessee Technological University (TTU) have a history of developing automated mobile robotic platforms in unstructured environments such as the power production and shipbuilding industries. Under the NSF STTR program, Robotic Technologies of Tennessee (RTT) has developed and commercialized a climbing mobile robotic welding system suited for welding in unstructured environments such as shipyards or construction of large structures. This system is called the Mobile Robotic Welding System (MRWS). The MRWS is capable of mechanizing weld processes while operating in inverted positions, even upside down.
When compared to manual welding processes or track based automated systems, the MRWS increases productivity, safety and quality. This system allows the weld technician to perform the weld process remotely making the job safer and more comfortable for the operator. This tends to reduce work place injuries related to repetitive motion and flying debris. In addition, the ability to control the welding from a control device allows the worker to remain in a comparatively better ergonomic position which enables older and less physically healthy welders to perform in their jobs longer. Finally, the MRWS better matches the expectations of younger generations of workers giving industrial recruiters a better chance of attracting young workers to join the industry (i.e., the industry is having trouble finding workers).
This system has been approved and qualified for the most stringent welding processes (NAVY requirements for ships) by several Tier-I shipbuilding manufacturers. Two commercial versions of the MRWS have been developed under the NSF STTR program. These systems are in use at the largest US shipyards. RTT’s mobile robotic welding systems have been a featured technology of the National Shipbuilding Research and have been featured at several industry forums (Shiptech 2009 – 2011, Fabtech 2010, 2011, 2012).
Fig. 1 Advanced MRWS-100 in Production
MRWS-Mini
Light weight, portable, highly mobile system for remote welding