Mechanical Vibrations

Yvon Mori, Consultant, France. Although retired from his main activities as an electronic engineer, he is still Chairman of the SEE French Riviera (Société de l'Electricité, de l'Electronique et des Technologies de l'Information et de la Communication) and the IEEE in France. He is also a COFRAC Auditor for programme 38 and trains engineers in mechanical vibration, shock analysis and electromagnetic compatibility for major companies. Before retirement he was, for 37 years, the manager of the environmental test and evaluation laboratory at Thales Underwater Systems in Sophia Antipolis, France.

Preface ix

Chapter 1 Vibration Theory 1

1.1 Problem 1

1.2 Different types of mechanical signals 4

1.3 Theory of vibration - reminders 19

1.4 Concept of mechanical impedance 46

1.5 Electromechanical analogies 68

1.6 Analog and logic computer simulation 78

1.7 Conclusion 80

Chapter 2 Signal Analysis 81

2.1 Overview 81

2.2 Spectra density of power 85

2.3 FS-Fourier Integral 103

Chapter 3 Test Preparation 109

3.1 Test demand analysis and associated test specifications 109

3.2 Test initiation 111

3.3 Test fixtures 112

3.4 Test execution 125

3.5 Test reporting 126

Chapter 4 Testing 129

4.1 Sine vibration tests 129

4.2 Vibration testing in noise or random 146

4.3 Specific tests 158

Chapter 5 Equipment Applications 163

5.1 Vibration sources and effects 163

5.2 Electronic equipment 167

5.3 Design of electronic equipment to vibrations 170

5.4 Study of a particular case - example of analysis of an electronic bay 191

Chapter 6 Controlling Generations of Vibrations and Shocks 197

6.1 General principles 197

6.2 Typical configuration of the equipment used 199

6.3 Traceability of tests 199

6.4 Control in sinusoidal mode 200

6.5 Random control 207

6.6 Shock and transient control 215

6.7 Combined vibrations control 223

6.8 Control: a few essential rules 227

Chapter 7 Metrology of Measurement and Testing Methods 229

7.1 Introduction to accelerometer sensors 229

7.2 Measurement amplifiers 239

7.3 Validation and verification of the testing means 245

7.4 Control of metrology in a testing laboratory 246

Chapter 8 Testing Means for Vibrations 253

8.1 Electrodynamic exciters 253

8.2 Hydraulic exciters 281

Conclusion 297

Appendices 299

Bibliography 403

Index 407