Course detail
Experimental Mechanics
FSI-REM Acad. year: 2019/2020 Winter semester
The course is concerned with the following topics: Fundamentals of methods of electrical measurement of mechanical quantities. Elaboration of continuous and discrete stochastic processes
in the time and the frequency domain. Methods for the determination of stresses and strains at a point and in a certain area of a body (especially resistance strain gages, reflection photoelasticity and brittle lacquers). Measurement of kinematic quantities, forces, torques and pressures.
Language of instruction
Czech
Number of ECTS credits
5
Supervisor
Learning outcomes of the course unit
Students will have a clear idea of current possibilities of experimental examination of selected mechanical quantities which are necessary for reliability assessment of machines and their elements. They will acquire basic practical knowledge and experiences and will be able to formulate real requirements for these activities in specialized institutions and professionally evaluate their results.
Prerequisites
Basic knowledge of analogue and digital engineering, measurement of electrical and non-electrical quantities, mathematical statistics, mechanics of bodies, strength of materials.
Planned learning activities and teaching methods
The course is taught through lectures explaining the basic principles and theory of the discipline. Teaching is suplemented by practical laboratory work.
Assesment methods and criteria linked to learning outcomes
Course-unit credit requirements: active participation in the seminars, good results of elaborated laboratory exercises, solving additional tasks in case of longer excusable absence.
Examination – combined (written and oral). In written part students have to prove knowledge of basic terms, important principles and their application; in the oral part the discussion over written part and records from laboratory exercises follows. None of these must be evaluated by the failing degree F.
Aims
The course objective is to make students familiar with current methods, instrumentation and computing technique for determination of input data which are necessary for computer modelling of machines and their elements and results verification. The course is focused especially on methods of investigation of stresses and strains, kinematic quantities, forces, torques, pressures and noise and on results elaboration using CAT/CAME systems.
Specification of controlled education, way of implementation and compensation for absences
Attendance at practical training is obligatory. One absence can be compensated by attending a seminar with another group in the same week, or by working out of substitute assignments. More absences are compensated by additional assignments according to the instructions of the tutor.
The study programmes with the given course
Programme M2A-P: Applied Sciences in Engineering, Master's
branch M-IMB: Engineering Mechanics and Biomechanics, compulsory
Programme M2A-P: Applied Sciences in Engineering, Master's
branch M-MET: Mechatronics, compulsory
Type of course unit
Lecture
26 hours, optionally
Teacher / Lecturer
Syllabus
1. Introduction into methodology of experimental work. Measuring chain.
2. Passive sensors of mechanical quantities.
3. Active sensors of mechanical quantities.
4. Continuous and discrete signals – methodology of their processing.
5. Digital signal filtering.
6. Devices for measurement of mechanical quantities.
7. Measurement of kinematic quantities.
8. Methods for determination of stresses and deformations of bodies.
9. Properties of resistance strain gages.
10. Criteria for optimal selection of strain gages.
11. Optical methods (photoelasticity, moiré, holography, specle.)
12. Brittle lacquers. Methods for measurement of residual stresses. Cracks detection.
13. Measurement of forces, torques and pressures.
Laboratory exercise
39 hours, compulsory
Teacher / Lecturer
Syllabus
1. Precaution for laboratory practice. Uncertainties in measurement
2. Theoretical problems in statistical elaboration of results of measurement
3. Problems in correlation and regression
4. Determination of gage factor of strain gage
5. Strain gages connection. Plain stress measurement – combination of bending and torque
6. Computer processing of random processes
7. Comparison of bar and chord in bending. Assessment of load cell spring element
8. Vibration of rotor systems
9. Vibration of blade
10. Local bending stresses in shell – theory and experiment
11. Comparison of self-compensation of strain gages
12. Transmission and reflection photoelasticity
13. Measurement of residual stresses by the hole drilling method