Mechanical Measurements

by Beckwith, Thomas G.; Marangoni, Roy D.; Lienhard, V, John H.

• ISBN13: 9780201847659
• ISBN10: 0201847655
• Edition: 6th
• Format: Paperback
• Copyright: 2006-08-07
• Publisher: Pearson

Summary

In the field of mechanical measurements, Mechanical Measurements continues to set the standard. With an emphasis on precision and clarity, the authors have consistently crafted a text that has helped thousands of students grasp the fundamentals of the field. Mechanical Measurements 6th edition gives students a methodical, well thought-out presentation that covers fundamental issues common to all areas of measurement in Part One, followed by individual chapters on applied areas of measurement in Part Two. This modular format fits several different course formats and accommodates a wide variety of skill levels.

Table of Contents

Preface	xv
I Fundamentals of Mechanical Measurement	1	(363)
1 The Process of Measurement: An Overview	2	(13)
1.1 Introduction	2	(1)
1.2 The Significance of Mechanical Measurement	3	(1)
1.3 Fundamental Methods of Measurement	4	(1)
1.3.1 Direct Comparison	4	(1)
1.3.2 Using a Calibrated System	4	(1)
1.4 The Generalized Measuring System	5	(3)
1.4.1 First, or Sensor-Transducer, Stage	5	(1)
1.4.2 Second, or Signal-Conditioning, Stage	5	(1)
1.4.3 Third, or Recording-Readout, Stage	6	(2)
1.5 Types of Input Quantities	8	(2)
1.5.1 Time Dependence	8	(1)
1.5.2 Analog and Digital Signals	8	(2)
1.6 Measurement Standards	10	(1)
1.7 Calibration	10	(1)
1.8 Uncertainty: Accuracy of Results	11	(1)
1.9 Reporting Results	12	(1)
1.9.1 Laboratory Note or Technical Memo	12	(1)
1.9.2 Full Report	13	(1)
1.9.3 Technical Paper	13	(1)
1.10 Final Remarks	13	(2)
2 Standards and Dimensional Units of Measurement	15	(349)
2.1 Introduction	15	(1)
2.2 Historical Background of Measurement in the United States	16	(1)
2.3 The SI System	17	(3)
2.3.1 Establishment of the SI System	17	(2)
2.3.2 Metric Conversion in the United States	19	(1)
2.4 The Standard of Length	20	(1)
2.4.1 Relationship of the Meter to the Inch	20	(1)
2.5 The Standard of Mass	21	(1)
2.6 Time and Frequency Standards	21	(1)
2.7 Temperature Standards	22	(3)
2.8 Electrical Standards	25	(1)
2.9 Conversions Between Systems of Units	26	(4)
2.10 Summary	30	(4)
3 Assessing and Presenting Experimental Data	34	(73)
3.1 Introduction	34	(1)
3.2 Common Types of Error	35	(7)
3.2.1 Classification of Errors	36	(5)
3.2.2 Terms Used in Rating Instrument Performance	41	(1)
3.3 Introduction to Uncertainty	42	(1)
3.4 Estimation of Precision Uncertainty	43	(3)
3.4.1 Sample versus Population	43	(2)
3.4.2 Probability Distributions	45	(1)
3.5 Theory Based on the Population	46	(5)
3.6 Theory Based on the Sample	51	(12)
3.6.1 An Example of Sampling	52	(2)
3.6.2 Confidence Intervals for Large Samples	54	(1)
3.6.3 Confidence Intervals for Small Samples	55	(6)
3.6.4 Hypothesis Testing for a Single Mean for a Small Sample Size (n less than or = to 30) 59
3.6.5 Hypothesis Testing for a Single Mean for a Large Sample Size (n > or = to 30)	61	(1)
3.6.6 The t-Test Comparison of Sample Means	62	(1)
3.7 The Chi-Square (χ²) Distribution	63	(8)
3.7.1 Goodness of Fit Based on the Gaussian Distribution	67	(4)
3.8 Statistical Analysis by Computer	71	(1)
3.9 Bias and Single-Sample Uncertainty	71	(2)
3.9.1 Single-Sample Precision Uncertainty	73	(1)
3.10 Propagation of Uncertainty	73	(2)
3.11 Examples of Uncertainty Analysis	75	(7)
3.11.1 Rating Resistors	75	(3)
3.11.2 Expected Uncertainty for Flowmeter Calibration	78	(4)
3.12 Minimizing Error in Designing Experiments	82	(1)
3.13 Graphical Presentation of Data	82	(10)
3.13.1 General Rules for Making Graphs	83	(2)
3.13.2 Choosing Coordinates and Producing Straight Lines	85	(7)
3.14 Line Fitting and the Method of Least Squares	92	(5)
3.14.1 Least Squares for Line Fits	92	(2)
3.14.2 Uncertainty in Line Fits	94	(1)
3.14.3 Software for Curve Fitting	94	(3)
3.15 Summary	97	(10)
4 The Analog Measurand: Time-Dependent Characteristics	107	(33)
4.1 Introduction	107	(1)
4.2 Simple Harmonic Relations	107	(2)
4.3 Circular and Cyclic Frequency	109	(1)
4.4 Complex Relations	110	(12)
4.4.1 Beat Frequency and Heterodyning	117	(1)
4.4.2 Special Waveforms	118	(1)
4.4.3 Nonperiodic or Transient Waveforms	118	(4)
4.5 Amplitudes of Waveforms	122	(1)
4.6 Frequency Spectrum	122	(2)
4.7 Harmonic, or Fourier, Analysis	124	(11)
4.7.1 The Discrete Fourier Transform	125	(2)
4.7.2 Frequencies in Discretely Sampled Signals: Aliasing and Frequency Resolution	127	(4)
4.7.3 An Example of Discrete Fourier Analysis	131	(4)
4.8 Summary	135	(5)
5 The Response of Measuring Systems	140	(44)
5.1 Introduction	140	(1)
5.2 Amplitude Response	141	(1)
5.3 Frequency Response	141	(1)
5.4 Phase Response	142	(1)
5.5 Predicting Performance for Complex Waveforms	142	(3)
5.6 Delay, Rise Time, and Slew Rate	145	(1)
5.7 Response of Experimental System Elements	145	(3)
5.8 Simplified Physical Systems	148	(1)
5.9 Mechanical Elements	148	(3)
5.9.1 Mass	148	(1)
5.9.2 Spring Force	149	(1)
5.9.3 Damping	150	(1)
5.10 An Example of a Simple Mechanical System	151	(1)
5.11 The Importance of Damping	152	(1)
5.12 Dynamic Characteristics of Simplified Mechanical Systems	153	(1)
5.13 Single-Degree-of-Freedom Spring-Mass-Damper Systems	153	(1)
5.14 The Zero-Order System	154	(1)
5.15 Characteristics of First-Order Systems	154	(7)
5.15.1 The Step-Forced First-Order System	155	(2)
5.15.2 The Harmonically Excited First-Order System	157	(4)
5.16 Characteristics of Second-Order Systems	161	(9)
5.16.1 The Step-Excited Second-Order System	161	(3)
5.16.2 The Harmonically Excited Second-Order System	164	(3)
5.16.3 General Periodic Forcing	167	(3)
5.17 Electrical Elements	170	(2)
5.18 First-Order Electrical System	172	(4)
5.19 Simple Second-Order Electrical System	176	(2)
5.20 Calibration of System Response	178	(1)
5.21 Summary	179	(5)
6 Sensors	184	(45)
6.1 Introduction	184	(1)
6.2 Loading of the Signal Source	185	(1)
6.3 The Secondary Transducer	185	(2)
6.4 Classification of First-Stage Devices	187	(3)
6.5 Variable-Resistance Transducer Elements	190	(1)
6.6 Sliding-Contact Devices	190	(2)
6.6.1 Potentiometer Resolution	192	(1)
6.6.2 Potentiometer Linearity	192	(1)
6.7 The Resistance Strain Gage	192	(1)
6.8 Thermistors	192	(1)
6.9 The Thermocouple	193	(1)
6.10 Variable-Inductance Transducers	193	(5)
6.10.1 Simple Self-Inductance Arrangements	195	(1)
6.10.2 Two-Coil Mutual-Inductance Arrangements	195	(3)
6.11 The Differential Transformer	198	(1)
6.12 Variable-Reluctance Transducers	198	(1)
6.13 Capacitive Transducers	199	(3)
6.14 Piezoelectric Sensors	202	(2)
6.15 Semiconductor Sensors	204	(5)
6.15.1 Electrical Behavior of Semiconductors	204	(1)
6.15.2 pn-Junctions	205	(2)
6.15.3 Photodiodes	207	(2)
6.16 Light-Detecting Transducers	209	(4)
6.16.1 Thermal Detectors	209	(1)
6.16.2 Photon Detectors	210	(1)
6.16.3 Applications	210	(3)
6.17 Hall-Effect Sensors	213	(1)
6.18 Some Design-Related Problems	214	(9)
6.18.1 Manufacturing Tolerances	215	(2)
6.18.2 Some Temperature-Related Problems	217	(4)
6.18.3 Methods for Limiting Temperature Errors	221	(2)
6.19 Summary	223	(6)
7 Signal Conditioning	229	(61)
7.1 Introduction	229	(1)
7.2 Advantages of Electrical Signal Conditioning	230	(1)
7.3 Modulated and Unmodulated Signals	230	(1)
7.4 Input Circuitry	231	(1)
7.5 The Simple Current-Sensitive Circuit	232	(2)
7.6 The Ballast Circuit	234	(2)
7.7 Voltage-Dividing Circuits	236	(2)
7.7.1 The Voltage-Dividing Potentiometer	236	(1)
7.7.2 Loading Error	237	(1)
7.7.3 Use of End Resistors	238	(1)
7.8 Small Changes in Transducer Resistance	238	(3)
7.9 Resistance Bridges	241	(8)
7.9.1 The Voltage-Sensitive Wheatstone Bridge	244	(2)
7.9.2 The Current-Sensitive Wheatstone Bridge	246	(1)
7.9.3 The Constant-Current Bridge	246	(1)
7.9.4 The AC Resistance Bridge	247	(1)
7.9.5 Compensation for Leads	248	(1)
7.9.6 Adjusting Bridge Sensitivity	249	(1)
7.10 Reactance or Impedance Bridges	249	(2)
7.11 Resonant Circuits	251	(1)
7.11.1 Undesirable Resonance Conditions	251	(1)
7.12 Electronic Amplification or Gain	252	(3)
7.13 Electronic Amplifiers	255	(1)
7.14 Operational Amplifiers	256	(8)
7.14.1 Typical Op-Amp Specifications	258	(1)
7.14.2 Applications of the Op Amp	259	(5)
7.15 Special Amplifier Circuits	264	(2)
7.15.1 Instrumentation Amplifiers	264	(1)
7.15.2 The Charge Amplifier	264	(2)
7.16 Filters	266	(1)
7.17 Some Filter Theory	267	(6)
7.18 Active Filters	273	(1)
7.19 Differentiators and Integrators	273	(2)
7.20 Shielding and Grounding	275	(2)
7.20.1 Shielding	275	(1)
7.20.2 Grounding	276	(1)
7.21 Component Coupling Methods	277	(2)
7.22 Summary	279	(11)
8 Digital Techniques in Mechanical Measurements	290	(45)
8.1 Introduction	290	(2)
8.2 Why Use Digital Methods?	292	(1)
8.3 Digitizing Mechanical Inputs	293	(1)
8.4 Fundamental Digital Circuit Elements	293	(9)
8.4.1 Basic Logic Elements	293	(4)
8.4.2 Combination of Logic Elements: The Flip-Flop	297	(1)
8.4.3 IC Families	297	(3)
8.4.4 IC Oscillators and Clock Signals	300	(1)
8.4.5 Digital Displays	301	(1)
8.5 Number Systems	302	(2)
8.6 Binary Codes	304	(6)
8.6.1 Binary-Coded Decimal	304	(1)
8.6.2 Position Encoders and Gray Code	305	(1)
8.6.3 Alphanumeric Codes	306	(4)
8.6.4 Bar Codes	310	(1)
8.7 Some Simple Digital Circuitry	310	(6)
8.7.1 Events Counter	310	(2)
8.7.2 Gating	312	(1)
8.7.3 Frequency Meter	312	(1)
8.7.4 Wave Shaping	313	(1)
8.7.5 Integrated-Circuit Counter and Frequency Meter	313	(1)
8.7.6 Multiplexing and Demultiplexing	314	(2)
8.8 The Computer as a Measurement System	316	(1)
8.9 The Microprocessor	317	(2)
8.10 The Microcomputer	319	(1)
8.10.1 Read-Only Memory (ROM)	319	(1)
8.10.2 Random Access Memory (RAM)	319	(1)
8.10.3 Input and Output Ports (I/O Ports)	320	(1)
8.10.4 External Buses	320	(1)
8.11 Analog-to-Digital and Digital-to-Analog Conversion	320	(8)
8.11.1 A Digital-to-Analog Converter	322	(1)
8.11.2 An Analog-to-Digital Converter	323	(2)
8.11.3 Analog-to-Digital Conversion Considerations	325	(1)
8.11.4 Digital Signal Processing	326	(2)
8.12 Digital Images	328	(1)
8.13 Getting It All Together	329	(1)
8.14 Summary	330	(5)
9 Readout and Data Processing	335	(29)
9.1 Introduction	335	(1)
9.2 The Electronic Counter	336	(4)
9.2.1 Event Counter	336	(1)
9.2.2 Time-Interval Meter	336	(3)
9.2.3 Events per Unit Time (EPUT) Meter	339	(1)
9.2.4 Count Error	339	(1)
9.3 Analog Electric Meter Indicators	340	(6)
9.3.1 Voltmeter Sensitivity	341	(1)
9.3.2 The Current Meter	342	(1)
9.3.3 AC Meters	342	(3)
9.3.4 The Multimeter and Resistance Measurement	345	(1)
9.4 Meters with Electronic Amplification	346	(1)
9.5 Digital-Readout Multimeters	346	(1)
9.6 The Cathode-Ray Oscilloscope (CRO)	347	(6)
9.6.1 Oscilloscope Amplifiers	348	(3)
9.6.2 Sawtooth Oscillator or Time-Base Generator	351
9.6.3 Synchronization or Triggering	151	(202)
9.7 Additional CRO Features	353	(2)
9.7.1 Multiple Trace	353	(1)
9.7.2 Magnification and Delayed Sweep	353	(1)
9.7.3 Digital Storage Oscilloscopes	353	(2)
9.7.4 Single-Ended and Differential Inputs	355	(1)
9.8 XY-Plotters	355	(1)
9.9 Digital Waveform Recorders	355	(1)
9.10 The Spectrum Analyzer	356	(2)
9.11 LabVIEW	358	(6)
II Applied Mechanical Measurements	364	(358)
10 Measurement of Count, Events per Unit Time, Time Interval, and Frequency	365	(21)
10.1 Introduction	365	(1)
10.2 Use of Counters	366	(2)
10.2.1 Electronic Counters	366	(1)
10.2.2 EPUT Meters	367	(1)
10.2.3 Time-Interval Meter	367	(1)
10.3 Stroboscopy and High-Speed Imaging	368	(4)
10.3.1 The Stroboscope	368	(2)
10.3.2 High-Speed Imaging	370	(2)
10.4 Frequency Standards	372	(3)
10.4.1 Global Positioning System Signals	373	(1)
10.4.2 Radio Time and Frequency Transmission	374	(1)
10.4.3 Quartz-Crystal Oscillators	374	(1)
10.4.4 Complex-Wave Oscillators and Function Generators	375	(1)
10.5 Lissajous Figures for Finding Frequency and Phase Relations	375	(4)
10.6 Heterodyne and Phase-Lock Measurements of Frequency	379	(3)
10.7 Measurement of Rotary Motion	382	(4)
11 Displacement and Dimensional Measurement	386	(27)
11.1 Introduction	386	(1)
11.2 A Problem in Dimensional Measurement	387	(1)
11.3 Gage Blocks	388	(3)
11.4 Assembling Gage-Block Stacks	391	(1)
11.5 Surface Plates	391	(1)
11.6 Temperature Problems	392	(2)
11.7 Use of Comparators	394	(1)
11.8 Monochromatic Light	395	(1)
11.9 The Interferometer	396	(2)
11.10 Measuring Microscopes	398	(4)
11.10.1 Fixed-Scale Microscopes	398	(2)
11.10.2 Filar Microscopes	400	(1)
11.10.3 Traveling and Traveling-Stage Microscopes	400	(1)
11.10.4 The Draw-Tube Microscope	400	(1)
11.10.5 Focusing	401	(1)
11.10.6 Digital Microscopes	402	(1)
11.11 Whole-Field Displacement Measurement	402	(1)
11.12 Displacement Transducers	402	(1)
11.13 The Differential Transformer or LVDT	403	(4)
11.13.1 Input Power	405	(1)
11.13.2 Advantages of the LVDT	406	(1)
11.14 Surface Roughness	407	(6)
12 Strain and Stress: Measurement and Analysis	413	(45)
12.1 Introduction	413	(3)
12.2 Strain Measurement	416	(1)
12.3 The Electrical Resistance Strain Gage	417	(1)
12.4 The Metallic Resistance Strain Gage	418	(3)
12.5 Selection and Installation Factors for Bonded Metallic Strain Gages	421	(1)
12.6 Circuitry for the Metallic Strain Gage	422	(1)
12.7 The Strain-Gage Ballast Circuit	423	(1)
12.8 The Strain-Gage Bridge Circuit	424	(3)
12.8.1 Bridges with Two and Four Arms Sensitive to Strain	425	(1)
12.8.2 The Bridge Constant	426	(1)
12.8.3 Lead-Wire Error	427	(1)
12.9 The Simple Constant-Current Strain-Gage Circuit	427	(1)
12.10 Temperature Compensation	428	(1)
12.10.1 The Adjacent-Arm Compensating Gage	428	(1)
12.10.2 Self-Temperature Compensation	428	(1)
12.11 Calibration	429	(2)
12.12 Commercially Available Strain-Measuring Systems	431	(1)
12.12.1 The Basic Indicator	432	(1)
12.13 Strain-Gage Switching	432	(1)
12.14 Use of Strain Gages on Rotating Shafts	432	(2)
12.15 Stress—Strain Relationships	434	(5)
12.15.1 The Simple Uniaxial Stress Situation	434	(1)
12.15.2 The Biaxial Stress Situation	435	(4)
12.16 Gage Orientation and Interpretation of Results	439	(7)
12.16.1 Gages Connected in Series	445	(1)
12.17 Special Problems	446	(2)
12.17.1 Cross Sensitivity	446	(1)
12.17.2 Plastic Strains and the Postyield Gage	446	(1)
12.17.3 Fatigue Applications of Resistance Strain Gages	446	(1)
12.17.4 Cryogenic Temperature Applications	446	(1)
12.17.5 High-Temperature Applications	447	(1)
12.17.6 Creep	448	(1)
12.17.7 Residual Stress Determination	448	(1)
12.18 Final Remarks	448	(10)
13 Measurement of Force and. Torque	458	(31)
13.1 Introduction	458	(2)
13.2 Measuring Methods	460	(1)
13.3 Mechanical Weighing Systems	461	(3)
13.3.1 The Analytical Balance	461	(1)
13.3.2 Multiple-Lever Systems	462	(2)
13.3.3 The Pendulum Force-Measuring Mechanism	464	(1)
13.4 Elastic Transducers	464	(7)
13.4.1 Calibration Adjustment	468	(1)
13.4.2 The Proving Ring	469	(2)
13.5 Strain-Gage Load Cells	471	(4)
13.6 Piezoelectric Load Cells	475	(1)
13.7 Ballistic Weighing	475	(2)
13.8 Hydraulic and Pneumatic Systems	477	(2)
13.9 Torque Measurement	479	(6)
13.9.1 Mechanical and Hydraulic Dynamometers	480	(3)
13.9.2 Electric Dynamometers	483	(2)
13.10 Transmission Dynamometers	485	(4)
14 Measurement of Pressure	489	(38)
14.1 Introduction	489	(1)
14.2 Static and Dynamic Pressures in Fluids	490	(2)
14.3 Pressure-Measuring Transducers	492	(1)
14.4 Manometry	493	(5)
14.5 Bourdon-Tube Gages	498	(1)
14.6 Elastic Diaphragms	498	(3)
14.6.1 Flat Metal Diaphragms	500	(1)
14.6.2 Corrugated Metal Diaphragms	500	(1)
14.6.3 Semiconductor Diaphragms	501	(1)
14.7 Additional Pressure Transducers	501	(5)
14.7.1 Strain Gages and Flat Diaphragms	501	(1)
14.7.2 Inductive Transducers	502	(1)
14.7.3 Piezoelectric Transducers	502	(1)
14.7.4 Capacitative Transducers	503	(1)
14.7.5 Strain-Gage Pressure Cells	504	(2)
14.8 Measurement of High Pressures	506	(2)
14.8.1 Electrical Resistance Pressure Gages	506	(2)
14.9 Measurement of Low Pressures	508	(3)
14.9.1 The McLeod Gage	508	(1)
14.9.2 Thermal Conductivity Gages	509	(1)
14.9.3 Ionization Gages	510	(1)
14.10 Dynamic Characteristics of Pressure-Measuring Systems	511	(4)
14.10.1 Gas-Filled Systems	512	(1)
14.10.2 Liquid-Filled Systems	513	(2)
14.11 Calibration Methods	515	(12)
14.11.1 Periodic Pressure Sources	516	(1)
14.11.2 Aperiodic Pressure Sources	517	(10)
15 Measurement of Fluid Flow	527	(50)
15.1 Introduction	527	(2)
15.2 Flow Characteristics	529	(2)
15.3 Obstruction Meters	531	(10)
15.3.1 Obstruction Meters for Incompressible Flow	531	(2)
15.3.2 Venturi Tube Characteristics	533	(1)
15.3.3 Flow-Nozzle Characteristics	534	(1)
15.3.4 Orifice Characteristics	534	(7)
15.3.5 Relative Merits of the Venturi, Flow Nozzle, and Orifice	541	(1)
15.4 Obstruction Meters for Compressible Fluids	541	(4)
15.4.1 Choked Flow and the Critical Flow Venturi Meter	544	(1)
15.5 Additional Flowmeters	545	(7)
15.5.1 Turbine Meters	545	(2)
15.5.2 Electromagnetic Flowmeters	547	(1)
15.5.3 Coriolis Flowmeters	548	(1)
15.5.4 Vortex Shedding Flowmeters	549	(1)
15.5.5 Ultrasonic Flowmeters	550	(1)
15.5.6 Positive Displacement Flowmeters	550	(1)
15.5.7 The Variable-Area Meter	551	(1)
15.6 Calibration of Flowmeters	552	(2)
15.7 Measurements of Fluid Velocities	554	(1)
15.8 Pressure Probes	555	(7)
15.8.1 Incompressible Fluids	556	(1)
15.8.2 Compressible Fluids	557	(1)
15.8.3 Total-Pressure Probes	557	(1)
15.8.4 Static-Pressure Probes	558	(2)
15.8.5 Direction-Sensing Probes	560	(2)
15.9 Thermal Anemometry	562	(3)
15.10 Doppler-Shift Measurements	565	(5)
15.10.1 Laser-Doppler Anemometry	566	(3)
15.10.2 Ultrasonic-Doppler Anemometry	569	(1)
15.11 Flow Visualization	570	(7)
16 Temperature Measurements	577	(79)
16.1 Introduction	577	(6)
16.2 Use of Thermal Expansion	583	(3)
16.2.1 Liquid-in-Glass Thermometers	583	(1)
16.2.2 Calibration and Stem Correction	584	(2)
16.2.3 Bimetal Temperature-Sensing Elements	586	(1)
16.3 Pressure Thermometers	586	(2)
16.4 Thermoresistive Elements	588	(8)
16.4.1 Resistance Thermometers	588	(2)
16.4.2 Instrumentation for Resistance Thermometry	590	(3)
16.4.3 Thermistors	593	(3)
16.5 Thermocouples	596	(17)
16.5.1 Application Laws for Thermocouples	598	(1)
16.5.2 Thermocouple Materials and Construction	598	(3)
16.5.3 Values of the Thermocouple EMF	601	(1)
16.5.4 Measurement of Thermocouple EMF	602	(8)
16.5.5 Electronic Instruments	610	(2)
16.5.6 Thermopiles and Thermocouples Connected in Parallel	612	(1)
16.6 Semiconductor-Junction Temperature Sensors	613	(1)
16.7 The Linear Quartz Thermometer	613	(2)
16.8 Pyrometry	615	(10)
16.8.1 Radiation Pyrometry Theory	616	(4)
16.8.2 Total-Radiation Pyrometry	620	(2)
16.8.3 Spectral-Band Pyrometry	622	(2)
16.8.4 Infrared Pyrometry	624	(1)
16.8.5 Thermal Imaging	625	(1)
16.9 Other Methods of Temperature Indication	625	(1)
16.10 Temperature Measurement Errors	626	(12)
16.10.1 Errors Associated with Convection, Radiation, and Conduction	626	(6)
16.10.2 Measurement of Temperature in Rapidly Moving Gas	632	(2)
16.10.3 Temperature Element Response	634	(3)
16.10.4 Compensation for Temperature Element Response	637	(1)
16.11 Measurement of Heat Flux	638	(4)
16.12 Calibration of Temperature-Measuring Device;	642	(14)
17 Measurement of Motion	656	(35)
17.1 Introduction	656	(1)
17.2 Vibrometers and Accelerometers	657	(1)
17.3 Elementary Vibrometers and Vibration Detectors	657	(2)
17.4 Elementary Accelerometers	659	(1)
17.5 The Seismic Instrument	659	(1)
17.6 General Theory of the Seismic Instrument	660	(5)
17.6.1 The Vibration Pickup	662	(1)
17.6.2 Phase Shift in the Seismic Vibrorneter	663	(2)
17.6.3 General Rule for Vibrometers	665	(1)
17.7 The Seismic Accelerometer	665	(3)
17.7.1 Phase Lag in the Accelerometer	667	(1)
17.7.2 Practical Design of Seismic Instruments	667	(1)
17.8 Calibration	668	(1)
17.9 Calibration of Vibrometers	669	(1)
17.10 Calibration of Accelerometers	669	(1)
17.10.1 Static Calibration	669	(1)
17.10.2 Steady-State Periodic Calibration	670	(1)
17.11 Response of the Seismic Instrument to Transients	670	(3)
17.12 Measurement of Velocity by the Laser Velocity Transducer	673	(1)
17.13 Vibration and Shock Testing	673	(1)
17.14 Vibrational Exciter Systems	674	(4)
17.14.1 Electromagnetic Systems	674	(1)
17.14.2 Mechanical-Type Exciters	675	(1)
17.14.3 Hydraulic and Pneumatic Systems	676	(1)
17.14.4 Relative Merits and Limitations of Each System	676	(2)
17.15 Vibration Test Methods	678	(1)
17.15.1 The Brute-Force Method	678	(1)
17.15.2 The Resonance Method	678	(1)
17.16 Shock Testing	679	(1)
17.17 Shock Rigs	680	(4)
17.17.1 Air Gun Shock-Producing Devices	681	(1)
17.17.2 Spring-Loaded Test Rigs	681	(1)
17.17.3 A Hydraulic-Pneumatic Rig	681	(1)
17.17.4 Gravity Rigs	682	(1)
17.17.5 Relative Merits and Limitations of Each Shock Rig	683	(1)
17.18 Practical Shock Testing	684	(7)
18 Acoustical Measurements	691	(31)
18.1 Introduction	691	(1)
18.2 Characterization of Sound (Noise)	692	(2)
18.3 Basic Acoustical Parameters	694	(6)
18.3.1 Sound Pressure	694	(1)
18.3.2 Sound Pressure Level	694	(2)
18.3.3 Power, Intensity, and Power Level	696	(1)
18.3.4 Combination of Sound Pressure Levels	697	(2)
18.3.5 Attenuation with Distance	699	(1)
18.4 Psychoacoustic Relationships	700	(2)
18.5 Sound-Measuring Apparatus and Techniques	702	(8)
18.5.1 Microphones	702	(2)
18.5.2 The Sound Level Meter	704	(2)
18.5.3 Frequency Spectrum Analysis	706	(4)
18.5.4 The Discrete Fourier Transform	710	(1)
18.6 Applied Spectrum Analysis	710	(2)
18.7 Measurement and Interpretation of Industrial and Environmental Noise	712	(3)
18.7.1 Equivalent Sound Level, Leq	712	(1)
18.7.2 Sound Exposure Level (SEL)	713	(1)
18.7.3 Sound Intensity Measurement	713	(2)
18.8 Notes on Some Practical Aspects of Sound Measurements	715	(2)
18.9 Calibration Methods	717	(1)
18.10 Final Remarks	718	(4)
III Appendices	722	(40)
A Standards and Conversion Equations	723	(3)
B Theoretical Basis for Fourier Analysis	726	(5)
C Number Systems	731	(5)
D Some Useful Data	736	(4)
E Stress and Strain Relationships	740	(15)
F Statistical Tests of Least Squares Fits	755	(4)
Answers to Selected Problems	759	(3)
Index	762