A--MODAL EXTRACTION DURING BASE DRIVE EXCITATION AND ACOUSTIC PRE-TEST ANALYSIS

NASA GRC has a requirement for MODAL EXTRACTION DURING BASE DRIVE EXCITATION AND ACOUSTIC PRE-TEST ANALYSIS. NASA GRC intends to contract with ATA Engineering, Inc, for this effort. ATA has a detailed understanding of the hardware being analyzed/tested that other vendors do not have and is proficient in the models/hardware. Any other contractors would require up front time to familiarize themselves with the models/hardware, which would impact the schedule and cost. The period of performance shall be June 1, 2015, through November 1, 2015. STATEMENT OF WORK: Part A A method is needed for extracting fixed base modes while a structure is mounted on a shake table. The key to the method is to use resultant accelerations of the table (such as rigid body accelerations) as references when calculating frequency response functions (FRFs). When this is done, the modes extracted from the resulting FRFs correspond to fixed base modes. NASA Glenn needs technical support during a modal survey performed on the MVF 3-DOF shaker. The modal survey will be a commissioning test using a representative test article to verify the MVF 3-DOF shake table. The contractor shall provide off-site and on-site support to help NASA Glenn with extracting modal parameters of the test article. The contractor support requirements shall be three weeks: two weeks in length, with an additional week to document results in an engineering report. The contractor will receive, from NASA GRC, time-history files containing acceleration data from the test article and shake table while the shake table is undergoing dynamic characterization runs used to calculate transfer functions from shaker control signals to test article accelerations. The contractor shall analyze this preliminary data. Once familiar with the preliminary data sets, the contractor shall travel to NASA Glenn to implement the methodology at the MVF. The method shall be documented to help NASA Glenn personnel conduct future fixed base modal surveys at its test facility. The contractor shall support weekly tag-ups to ensure the technology transfer to government. PART B NASA GRC requires the development of vibroacoustic models of the Orion E-STA test article. A low frequency finite element method/boundary element method (FEM/BEM) model and a high-frequency statistical energy analysis (SEA) model will be developed by the contractor. These models will be used to predict the vibration response of the E-STA structure during the acoustic test and to evaluate differences in vibration response between the test and flight articles. NASA GRC will provide model data and test plans. The Government intends to acquire a commercial item using FAR Part 12. Interested organizations may submit their capabilities and qualifications to perform the effort in writing to the identified point of contact not later than 4:30 p.m. local time on May 19, 2015. Such capabilities/qualifications will be evaluated solely for the purpose of determining whether or not to conduct this procurement on a competitive basis. A determination by the Government not to compete this proposed effort on a full and open competition basis, based upon responses to this notice, is solely within the discretion of the government. Oral communications are not acceptable in response to this notice. All responsible sources may submit an offer which shall be considered by the agency. NASA Clause 1852.215-84, Ombudsman, is applicable. The Center Ombudsman for this acquisition can be found at http://prod.nais.nasa.gov/pub/p ub_library/Omb.html .