Measurement and Experiment
FSI-ZEMAcad. year: 2017/2018
The course familiarizes students with procedures and principles of technical experiment in work of a mechanical engineer. It defines the basics of the modern methods applied for measuring of mechanical quantities, and explains the structure of the measuring and control chain. The course deals with the analysis of the analog and digital signals in time and frequency domain too. A part of the course is also dedicated to the measurement of kinematic quantities, forces, torques, pressure and noise. The course is divided into the following blocks: acoustic measurements in engineering, fundamentals of experimental modal analysis, monitoring of a machine technical condition and service life tests of mechanical units.
Learning outcomes of the course unit
An overview of the contemporary experimental detection possibilities of selected mechanical quantities needed for an assessment of failure-free operation of machines and their parts. They will be provided with fundamental practical knowledge and experience with methods of non-electrical physical quantities measurement. Students gain general knowledge of state-of-art measurement technology and methods of evaluation and interpretation of the experimental results.
Fundamental knowledge in area of mathematics, numerical mathematics, statistics and probability, physics, mechanics and electrical engineering.
Recommended optional programme components
Recommended or required reading
BERNARD, Jaroslav, 1999. Technický experiment. Praha: Vydavatelství ČVUT. ISBN 80-010-1901-2. (CS)
TŮMA, Jiří, 1997. Zpracování signálů získaných z mechanických systémů užitím FFT. Praha: Sdělovací technika. ISBN 80-901-9361-7. (CS)
Planned learning activities and teaching methods
The course is taught through lectures explaining the basic principles and theory of the discipline. Teaching is supplemented by practical laboratory work.
Assesment methods and criteria linked to learning outcomes
Course-unit credit is awarded on the following conditions: active participation in the seminars, good results of elaborated laboratory exercises.
Examination: course is finished by the final test during 5th week. In the test, the student has to prove knowledge of basic terms, important principles and their application.
Language of instruction
The aim of the course is to present contemporary methods, experimental instrumentation and computer technology for measurement of physical quantities to the students. Measured physical quantities are usually used as input parameters for mathematical modeling of machines and machine parts. Verification of such models is also possible by comparison of measured and simulated data. The course deals with analysis of the kinematic quantities, forces, moments, pressures and noise and with processing of obtained results by using of CAT/CAME methods (computer aided testing/computer assisted measurement and evaluation).
Specification of controlled education, way of implementation and compensation for absences
Attendance at lectures is recommended; attendance at laboratory practicals is obligatory and checked by the lecturer. One absence can be compensated by attending a seminar with another study group in the same week, or by elaboration of substitute tasks. In case of longer absence, compensation of missed lessons depends on the instructions of course supervisor – special task elaboration.
Type of course unit
16 hours, optionally
Teacher / Lecturer
1. Technical experiment.
• Process of the technical problem solution.
• Technical experiment as a source of knowledge.
• Fundamentals of the experiment and measurement methods.
• Measurement chain.
2. Transducers of physical quantities.
• Measurement of the physical quantities, classification of the transducers.
• Technical specifications of the transducers.
• Temperature sensors, non-contact pyrometers.
• Accelerometers and gyroscopes with iMEMS technology.
3. Digital signals and data.
• Classification of the analog and digital signals.
• Digital sampling, sampling theorem, aliasing phenomenon.
• Discrete Fourier transformation, FFT fundamentals.
• Aliasing phenomenon in the frequency domain.
4. Time-domain signal analysis.
• Mean, variance, root mean square.
• Crest factor.
• Trend analysis.
• Digital filtration, synchronous detection.
5. Frequency-domain signal analysis.
• Fourier transformation with resampling.
• Application of multispectrum.
• Order analysis, tracking.
• Cepstral analysis.
6. Sound measurement
• Free field, near field, diffusion field.
• Measured quantities, ISO acoustic weighting filters.
• Noise source identification.
• Mapping of the acoustic fields.
7. CAT/CAME systems.
• Measurement chain.
• Plug-in modules (AD, DA, DIO, Count).
• Global Positioning System.
• Methods of localization, GPS errors.
8. Fundamentals of the experimental modal analysis.
• Signal analysis, mechanical system analysis.
• Mechanical and analytical model.
• Classification of the exciters.
• Methods of the oscillation data analysis.
labs and studios
16 hours, compulsory
Teacher / Lecturer
1. Workplace safety in the laboratory.
2. Demonstration of selected laboratory tests.
3. Transducers of the physical quantities.
4. Calibration of the accelerometers and microphones.
5. Specific instruments of LabVIEW.
6. Programming of the measuring application with LabVIEW.
7. Acoustic measuring in a free field conditions.
8. Experimental estimation of modal parameters of a fixed beam.