Devin Burns PhD, Force Balance Engineer, NASA Langley Research Center
The presentation will highlight the significance of a wind tunnel force balance in ground-based experimental aeronautics research and development at NASA. The competing design objectives associated with the balance acting as a structural component and a precision force transducer will be explained. Traditional manufacturing practices used to produce force balances, which currently require six months of fabrication time, will be reviewed.
Single-component additively manufactured 316L stainless steel force transducers were produced as part of a feasibility study and will be discussed. The transducers consisted of cantilever test beams fabricated using select laser melting. Strain gages were applied to the beams and a calibration process was performed to access the transducer performance relative to a transducer quality material fabricated using traditional manufacturing techniques.
Finally, current efforts to replicate a conventionally manufactured five-component balance from ultra high-strength steel using additive manufacturing will be discussed. This effort seeks to assess selective laser melting’s ability to produce complex geometric features common to force balances and the spring quality of the laser melted material. A manufacturing plan including heat treatments and secondary machining processes will be outlined that offers the potential to reduce fabrication time from months to weeks.