INTRODUCTION

Earlier chapters describe equipment used in vibration measurements. For example, detailed information concerning transducers, their characteristics, and how these characteristics are influenced by environmental factors is given in Chap. 12. The various measurement system components and the characteristics which determine their selection are described in Chaps. 13 and 14. The use of such measurement systems in vibration problems may involve only one or two engineers as in monitoring the condition of machinery in a factory (Chap. 16), in some problems in modal testing (Chap. 21), in measurements in building structures (Chap. 24), in measuring torsional vibration in reciprocating and rotating engines (Chap. 38), and in the balancing of rotating machinery (Chap. 39). In contrast, in the aerospace industry, some measurement problems are so complex that teams of engineers and several divisions of the company may be involved. Yet all these examples share certain basic measurement procedures. It is these basic procedures (rather than measurement details, which vary from problem to problem) that are considered here. Thus, this chapter includes a general discussion of (1) planning measurements to achieve stated objectives, (2) selecting the type of measurements which should be made to achieve these objectives, (3) selecting transducers, (4) mounting transducers, (5) mounting cable and wiring (including shielding and grounding), (6) selecting techniques for the field calibration of the overall measurement system, (7) collecting and logging the data obtained, and (8) conducting a measurement error analysis.

The best method of analyzing the vibration measurement data, once they...