Dynamic Engineering Measurement Laboratory



The research scope of the Dynamic Engineering Measurement Laboratory (DEML) mainly covers in the fields of vibration, acoustics and ultrasound metrology.

Vibration measurement has a wide range of applications. In additional to the calibration capability of accelerometers, charge amplifier and vibration meters, the DEML is also well equipped with the modal analysis for structural vibrations and enhancement techniques, the experimental analysis and control techniques of floor vibrations for factory buildings, and the monitoring, analysis and preventing techniques of environmental vibrations, and rotor rotating unbalanced and roundout measurement of rotor under spinning test. Also the DEML serves the monitoring and fault diagnostics of mechanical equipments, performance verification of vibration isolators, precision measurement of floor vibrations, etc.. Furthermore, the advanced technology in non-contact precision measurement is under developing at the moment.

In DEML, The calibration service of microphone, sound pressure calibrators, and sound level meters in acoustics field helps to support the high precision measurement application for noise control in production facilities, transportation, and environmental concerns. The laboratory has also developed core technologies in performance test of standard microphones and sound sources, frequency response test of microphones, directionality characteristics of sound-level meters, absorption coefficients and impedance measurement of sound-absorbing materials, performance test and the design service for the anechoic chambers, and wind turbine noise measurement technique, the sound insulation and reverberation time measurement of building or construction, audio performance test of public addressing system and audio device, etc.

In the ultrasound metrology, DEML has included the capabilities of the frequency response characteristics, the sound pressure level and the directionality of ultrasonic probe; for underwater acoustics, the hydrophone sensitivity, the output power and intensity measurements. Also, the DEML has established the ability on ultrasonic scanning technique for structure crack and defect inspection.

Calibration and Measurement Capabilities, CMCs

Since 2004, the calibration and measurement capabilities (CMCs) in the areas of Acoustics, Ultrasound and Vibration (AUV) have been incorporated in BIPM's key comparison database (KCDB.). It declares that DEML's CMCs have gain international recognition and its availability of offering measurement service worldwide.

Technical Services
  • Establishment of calibration systems for accelerometers, vibrometers, charge amplifiers
  • Vibration tests, analysis, and improvement for mechanical components
  • Functionality tests for vibration testing euipments
  • Measurement of micro vibrations, monitoring and analysis of environmental vibrations
  • Seismometer and vibration monitoring system functionality and validation test
  • Stress analysis for structural dynamics, module testing, and finite element analysis
  • Calibration techniques transfer for microphones, sound pressure calibrators, and sound-level meters
  • Sound absorbing coefficient testing equipments
  • Development of online testing systems for electro-acoustic products
  • Emitted noise (sound power, sound pressure) measurements, sound quality evaluation and noise reduction
  • Designing and performance testing service for audiometric booths/ hearing test rooms, semianechoic/anechoic rooms, studio rooms
  • Factory/ working area noise monitoring and reduction strategy
  • Building acoustics evaluation service
  • Audio equipments test and measurement

Research Projects

  • Primary shock calibration using laser interferometry
  • Spinning test technique for rotor roundout and unbalancing
  • Microphone reciprocity calibration technique in free-field conditions
  • Non-Contact vibration measurement technique

 Low Shock Primary Calibration System    Low Shock Primary Calibration system         


 E300 2   

Calibration System for Standard Microphones by Reciprocity Technique