Sensors and Instrumentation, Aircraft/Aerospace and Dynamic Environments Testing, Volume 7: Proceedings of the 40th IMAC, A Conference and Exposition ... Society for Experimental Mechanics Series)

Sensors and Instrumentation, Aircraft/Aerospace and Energy Harvesting, Volume 7: Proceedings of the 40th IMAC, A Conference and Exposition on Structural Dynamics, 2020, the seventh volume of nine from the Conference brings together contributions to this important area of research and engineering. The collection presents early findings and case studies on fundamental and applied aspects of Shock & Vibration, Aircraft/Aerospace, Energy Harvesting & Dynamic Environments Testing including papers on: Alternative Sensing & Acquisition Active Controls Instrumentation Aircraft/Aerospace & Aerospace Testing Techniques Energy Harvesting Preface Contents 1 Test Data Measurement Uncertainty Analysis 1.1 Introduction 1.2 Background 1.3 Random Uncertainty 1.4 Systematic Uncertainty 1.5 Final Uncertainty Calculation 1.6 Consultant 1.7 ASME and ISO Compliance 1.8 Example 1.9 Conclusion 2 Forced Vibrations of Damped Non-homogeneous Timoshenko Beams Nomenclature 2.1 Introduction 2.2 Basic Structure 2.3 Solution Approaches 2.3.1 Analytical Approach 2.3.2 Numerical Approach 2.4 Numerical Examples 2.4.1 Free/Fixed Boundary Conditions 2.4.2 Fixed/Fixed Boundary Conditions 2.5 Assumed Modes Method 2.6 Conclusion References 3 Parametric Simulations of the BARC Model in SDOF and MIMO Configurations for Estimating Service Environment Severity 3.1 Introduction 3.2 Methods 3.2.1 Structure Modeling in ABAQUS 3.2.2 Usage of Existing Data 3.2.3 Boundary Conditions and Parameterization 3.3 Analysis 3.3.1 History Outputs 3.3.2 Implicit Analysis Boundary Conditions Modal Analysis Mode-Based Steady-State Dynamics 3.3.3 Explicit Analysis Boundary Conditions Computational Cost 3.3.4 Frequency Response and Data Analysis Spectral Measurements Scalar Measurements Correlation Measurements 3.4 Results and Discussion 3.5 Conclusion Appendix Appendix A: Accelerometer Frequency Responses Frequency Responses of Each Accelerometer in the x-Direction Accelerometer 1 Accelerometer 3 Accelerometer 5 Frequency Responses of Each Accelerometer in the y-Direction Accelerometer 1 Accelerometer 3 Accelerometer 5 Frequency Responses of Each Accelerometer in the z-Direction Accelerometer 1 Accelerometer 3 Accelerometer 5 References 4 Experimental Modal Analysis of a Resonant Plate During a Mid-Field Pyroshock Replication Test 4.1 Introduction 4.2 Theory and Background 4.2.1 Modal Analysis 4.2.2 Formulation of SWAT-TEEM 4.3 Modal Analysis of the Resonant Plate Test 4.4 Conclusion References 5 A Parameter Study of the Matrix Power Control Algorithm 5.1 Introduction 5.2 Explanation of MPCA 5.3 Simulation Models 5.4 Simulation Results 5.5 Experimental Results 5.6 Conclusion References 6 Acoustic Resonance Testing on Production Lines with the Smart Impulse Hammer WaveHitMAX 6.1 Introduction 6.2 Background 6.3 Technical Implementation 6.4 Measurement Setup 6.5 Analysis 6.5.1 Feature Extraction 6.5.2 Feature Selection 6.5.3 Classification 6.6 Conclusion References 7 Techniques for Modifying MIMO Random Vibration Specifications 7.1 Introduction 7.2 Typical MIMO Testing Process 7.3 Options for MIMO Response-Control Specifications When Data Is Not Available 7.3.1 Use a Generic Straight-Line Specification from a Standard 7.3.2 Apply the Specification from the Old System to the New System 7.3.3 Modify the Specification to Account for the Differences Between A and B 7.4 Techniques for Specification Modification 7.4.1 Frequency Averaging and Frequency Modification 7.4.2 DOF Averaging 7.5 Example Using the BARC 7.6 Observations 7.6.1 Frequency Averaged Specification 7.6.2 Frequency Modified Specification 7.6.3 All DOF Averaged SPEC 7.6.4 Group DOF Averaged SPEC 7.7 Conclusion References 8 On the Selection of Mode Shapes Used in Optimal Sensor Placement 8.1 Introduction 8.2 The Railway Bridge and Numerical Modeling 8.3 Application of the EFI Method and the Optimal Sensor Placement 8.4 Conclusion References 9 Thoughts on Automatic Impulse Hammer Parameters and Sensor Fixation Methods 9.1 Introduction 9.2 Automated Impulse Hammer Parameters 9.2.1 System Description 9.2.2 Influence of the Bolt Mass 9.2.3 Influence of the Spring Stiffness 9.3 Sensor Fixation Parameters 9.3.1 Technical Properties of Fixation Methods 9.3.2 Experimental Setup 9.3.2.1 Normal Direction 9.3.2.2 Tangential Direction 9.4 Summary References 10 Modal Correlation of Complex Aerospace Joints Using Automated Variable Substitution Nomenclature 10.1 Introduction 10.2 Analysis Approach 10.2.1 Design Variable Definition 10.2.2 Symbolic Substitution 10.2.3 Iteration Value Assignment 10.2.4 Nastran SOL200 Deck Setup 10.3 Shell Automation Script 10.3.1 Initial Script Setup 10.3.2 Iteration Loop Definition 10.3.3 Shell Script Execution 10.3.4 Output Review 10.4 Case Study 10.5 Conclusion References 11 Multi-Shaker Testing at the Component Level 11.1 Introduction 11.2 Field and Laboratory Configurations 11.3 System Tests 11.4 ICE Tests 11.5 SDOF Tests 11.6 Overall System, ICE, and SDOF Comparison 11.7 Conclusion References 12 Balancing Impedance and Controllability in Response Reconstruction 12.1 Introduction 12.2 Assembly and Environment Definitions 12.3 MIMO Simulations 12.3.1 Roving Hammer FRFs 12.3.2 Mathematical Model 12.3.3 Shaker Selection Algorithm 12.4 Methodology 12.5 MIMO Reconstruction 12.6 Simulation with Condition Number Threshold 12.6.1 Condition Number Threshold Implementation 12.6.2 Simulation Results with Condition Number Threshold 12.7 Conclusion References 13 Challenges and Considerations When Using Hydraulic Modal Shaking in Large-Scale Modal Testing 13.1 Background 13.2 Hydraulic Actuator Basics 13.3 Hydraulic Actuator Nonlinear Distortion 13.4 Shaker Performance Limits 13.5 Operational and Safety Concerns 13.6 Pretest Analysis: End-to-End Force Response Simulation 13.7 Hydraulic Multi-Axis Shaker Vibration Test Facilities and Beyond 13.8 Conclusion References 14 Damage and Loose Rivet Detection on an Airbus A320 Panel Using Non-contact Measurement Techniques 14.1 Introduction 14.2 Experimental Setup 14.2.1 Digital Image Correlation (DIC) Setup 14.2.2 Laser Doppler Vibrometer (LDV) Setup 14.3 Results 14.3.1 DIC Full-Field Modal Analysis and Damage Detection 14.3.2 Damage Detection with Nonlinear Analysis 14.3.3 Damage Detection with ML Techniques 14.4 Conclusions References 15 Localisation of Sonic Sources on a Contemporary Violin Made on a Guarneri del Gesù Model 15.1 Introduction 15.2 Sound Source Localisation Methods 15.3 Experimental Setup 15.4 Sound Source Localisation 15.4.1 Localisation of Sound Sources 15.4.2 Structural Mode Shape Qualitative Analysis 15.5 Conclusion References