SBIR-STTR Award

Longhurst Engineering, PLC, and Vanderbilt University propose an in-space friction stir welding (FSW) machine for joining complex structural aluminum components. The proposed FSW machine is innovative because it can be deployed by 2 people and be used to weld complex surfaces that extend beyond linear welding applications. The in-space FSW machine is a 3 axis system that can be mounted to work pieces of varying geometry, position, and orientation through the use of a high performance vacuum system or mechanical clamps. The key enabler of the proposed FSW machine is a self adjusting and self aligning FSW (SAA-FSW) tool that eliminates the need for automated actuators. In addition, a collection of force reduction techniques will be included as part of the system. When combined together, it is theorized that the effect will be significant and will lead to the advancement of FSW by reducing structural rigidity requirements of FSW machines.Our work plan begins by determining the net effect of the combined force reduction techniques. Substantial effort is given to the development of a preliminary SAA-FSW tool which includes experimental welding. Lastly, a preliminary set of engineering plans will be delivered based upon the results from the development of the SAA-FSW tool and force reduction techniques.

Potential NASA Commercial Applications:
(Limit 1500 characters, approximately 150 words) The successful development of a 2 person portable FSW machine will enable in-space applications of FSW. This includes the joining and assembling of panels as well as in-situ repair operations needed for prolong and deep space missions beyond low Earth orbit. By no longer preassembling the structures, greater payload densities could be achieved, which would reduce the overall costs. The welding and assembly would then be done at the point of use via the in-space FSW machine.In addition, the SAA-FSW tool technology can be used to replace or substitute the actuating mechanisms used with NASA's self-reacting FSW tool technology. With the SAA-FSW tool, automatic actuation and control systems are eliminated.

Potential NON-NASA Commercial Applications:
(Limit 1500 characters, approximately 150 words) Boeing, Lockheed Martin, and other aerospace companies have FSW applications very similar to NASA that would benefit from this portable system. These companies would increase the efficiency of welding operations by having a portable FSW machine to supplement existing immobile machines. Perhaps the most potential for a portable FSW machine lies with small businesses that will be poised to enter the FSW industry within the next couple of years as the major FSW patents expire. Entry into the FSW industry requires a rather significant investment to obtain the large machines. With a small portable FSW machine, entry will be much easier for these companies.

Technology Taxonomy Mapping:
(NASA's technology taxonomy has been developed by the SBIR-STTR program to disseminate awareness of proposed and awarded R/R&D in the agency. It is a listing of over 100 technologies, sorted into broad categories, of interest to NASA.) In Situ Manufacturing Joining (Adhesion, Welding) Machines/Mechanical Subsystems Spacecraft Design, Construction, Testing, & Performance (see also Engineering; Testing & Evaluation)