2. PURPOSE, OBJECTIVE, AND BACKGROUND OF WORK TO BE PERFORMED: THE FUNDAMENTAL AERO PROGRAM (FAP), SUBSONIC…

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2. PURPOSE, OBJECTIVE, AND BACKGROUND OF WORK TO BE PERFORMED: THE FUNDAMENTAL AERO PROGRAM (FAP), SUBSONIC FIXED WING (SFW) PROJECT, IS PERFORMING FOUNDATIONAL RESEARCH IN THE AREA OF NONLINEAR AERODYNAMIC MODELING. MILITARY AND CIVILIAN REQUIREMENTS FOR PERFORMANCE AND SAFETY IMPROVEMENTS HAVE FOCUSED INTERNATIONAL RESEARCH ON IMPROVING THE FIDELITY OF AERODYNAMIC MODELING ESPECIALLY IN PORTIONS OF THE FLIGHT ENVELOPE WHERE NONLINEAR UNSTEADY BEHAVIORS OCCUR. A KEY ASPECT OF THE SFW MODELING EFFORT IS TO PRODUCE A COMPREHENSIVE METHODOLOGY FOR OBTAINING APPROPRIATE AERODYNAMIC MATH MODELS OVER AN EXTENDED FLIGHT ENVELOPE. THE METHODOLOGY INCLUDES DEVELOPMENT OF GROUND AND FLIGHT TEST TECHNIQUES AND IDENTIFICATION ALGORITHMS FOR OBTAINING THE MATH MODELS FROM MEASURED DATA. THIS SFW EFFORT, TO DATE, HAS LACKED THE MODERN DESIGN OF EXPERIMENT (DOE) AND RESPONSE SURFACE MODELING (RSM) TECHNOLOGIES THAT CAN IMPROVE ACCURACY AND EFFICIENCY OF THE EXPERIMENTAL PROCESS. THE LONG TERM GOAL OF THIS TASK IS TO INCORPORATE DOE/RSM TECHNOLOGY INTO THE DEVELOPMENT OF GROUND-BASED DYNAMIC TEST TECHNIQUES. TO SUPPORT ADVANCED DYNAMIC TESTING, NASA LARC IS DEVELOPING APPROPRIATE WIND TUNNEL MODELS AND A NEW DYNAMIC TEST RIG (DR) FOR THE LARC 12-FOOT WIND TUNNEL (LARC 12-FT) THAT WILL ALLOW A BROAD SPECTRUM OF TEST TECHNIQUES INCLUDING DOE/RSM TECHNOLOGY. 3. DESCRIPTION OF THE WORK TO BE PERFORMED: THE CONTRACTOR SHALL PERFORM THE FOLLOWING TASK REQUIREMENTS: DURING THE PROPOSED PERIOD, THE RESEARCH WILL BE CLOSELY COORDINATED WITH THE NASA FAP/SFW PROJECT TM. THE PROPOSED RESEARCH PROGRAM WILL INCLUDE THREE PARTS: (1) DYNAMIC RIG CONTROL SOFTWARE, (2) DYNAMIC RIG VALIDATION, AND (3) DOE/RSM DYNAMIC TEST METHODS. SUBTASK 3.1 DYNAMIC RIG CONTROL SOFTWARE DEVELOP NEW CONTROL SOFTWARE THAT SHALL FACILITATE THE USE OF ARBITRARY EXPERIMENTAL INPUTS AND DOE/RSM TECHNOLOGY. SOFTWARE SHALL BE WRITTEN USING LABVIEW. AS A FIRST STEP, CONTROL ALGORITHMS ARE BEING DEVELOPED FOR A SMALL MODEL OF THE DYNAMIC RIG KNOWN AS THE MINI-ROLL RIG. THE CONTRACTOR SHALL ASSIST THE NASA ENGINEER IN DEVELOPING CONTROL SOFTWARE FOR THE MINI-RIG TO LATER BE TRANSFERRED TO THE LARC 12-FT DR. THE SOFTWARE SHALL ALLOW THE USER TO CONTROL THE RIG, MONITOR THE CURRENT POSITION OF THE RIG, AND PROVIDE FEEDBACK IF THE USER EXCEEDS THE LIMITS OF THE ROLL RIG. ONCE THIS TASK IS COMPLETE, THE SOFTWARE SHALL BE UPLOADED, BENCH TESTED, AND IMPLEMENTED ON THE LARGER SCALE DYNAMIC RIG IN THE LARC 12-FT WIND TUNNEL. SUBTASK 3.2 DYNAMIC RIG VALIDATION LEVERAGE THE POWER OF DESIGN OF EXPERIMENTS (DOE) AND RESPONSE SURFACE METHODOLOGY (RSM) TO EXERCISE, VALIDATE, AND EXAMINE THE SOURCES OF ERROR ON THE DR. THESE METHODS SHALL ALSO ALLOW FOR OPTIMIZATION OF THE RIG TO BE CONDUCTED. DIAGNOSTIC TESTS SHALL BE DEVELOPED TO ASCERTAIN THE OPERATIONAL READINESS OF THE RIG FOR DYNAMIC TESTING. THESE TESTS SHALL INCLUDE ASSESSMENT OF TWO IMPORTANT ASPECTS OF THE TEST FACILITY: (1) CAPABILITY TO MEASURE STATIC AND DYNAMIC TIME HISTORIES OF THE AERODYNAMIC FORCES AND MOMENTS, AND (2) ASSESSMENT OF INPUT COMMAND FIDELITY AND OUTPUT DATA QUALITY AS A FUNCTION OF THE FULL RANGE OF ANGLE OF ATTACK, SIDESLIP, INPUT AMPLITUDES, AND FREQUENCIES. PRIMARY INPUT DATA OF INTEREST ARE TUNNEL SETTINGS, RIG POSITION, AND FIDELITY OF RIG MOTIONS TO INPUT COMMAND TIME HISTORIES. COMMAND TIME HISTORIES INCLUDE RAMPS, FREQUENCY SWEEPS, AND SINGLE HARMONIC INPUTS. PRIMARY OUTPUT DATA OF INTEREST ARE STATIC MAP COEFFICIENTS, AND AERODYNAMIC COEFFICIENT TIME HISTORIES, WHERE . FOR SMALL AMPLITUDE OR LINEAR AERODYNAMIC CASES, IN-PHASE AND OUT-OF-PHASE COEFFICIENTS, AND RESPECTIVELY, WHERE AND , PROVIDE ADDITIONAL OUTPUTS OF INTEREST. USING DESIGN OF EXPERIMENTS AND RESPONSE SURFACE METHODS UNDER GUIDANCE OF THE CONTRACT PROFESSOR AND IN COLLABORATION WITH NASA ENGINEERS, THE CONTRACTOR SHALL DEVELOP DIAGNOSTIC TESTS TO ASCERTAIN THE OPERATIONAL READINESS OF THE DR FOR DYNAMIC TESTIN