Vibration Measurement

Dept. of Mechanical Engineering

Yungpeng Wang

南臺科技大學STUST

Vibration Measurement System

南臺科技大學STUST

A/D

Memory1

Memory2

WeightingDynamic

Frequency Analyzer

Display

Pre-Amplifier

Transducer

Transducer

1. Accelerometer: acceleration

Piezoelectric Accelerometer Charge type ICP type (Integrated Circuit -

Piezoelectric)

2. Vibration Pickup: velocity

3. Proximeter: displacement

南臺科技大學STUST

PZT Accelerometer

Velocity Pickup

Proximeter

Pre-Amplifier

1. Charge Type Piezoelectric Accelerometer

Pre-amplifier: Charge to voltage conversion Amplification Filter

2. ICP Type Piezoelectric Accelerometer

Pre-amplifier: Power supplies Amplication Filter

南臺科技大學STUST

Dynamic Frequency Analyzer

南臺科技大學STUST

1. Overall AnalysisVibration Meter

2. Narrow BandConstant Band Analysis (FFT Analysis)High ResolutionDiagnose for Vibration Source, System

Analysis

Dynamic Frequency Analyzer

南臺科技大學STUST

2. Octave BandConstant Percentage Band Analysis (CPB

Analysis)Vibration Energy DistributionMonitoring, Human Factor Analysis

3. Overall AnalysisVibration Meter

Dynamic Frequency Analyzer

南臺科技大學STUST

3. Octave BandConstant Percentage Band Analysis (CPB

Analysis)Vibration Energy DistributionMonitoring, Human Factor Analysis

Dynamic Frequency Analyzer

南臺科技大學STUST

Two Problems

1. Aliasing Solution: Anti-aliasing filter (Low-pass

filter)

南臺科技大學STUST

Two Problems

2. Leakage Solution: Time Weighting

南臺科技大學STUST