Experimental Methods in Mechanical Engineering


It is intended that the students contact with various experimental techniques that allow knowing or predict the responses exhibited by various mechanical systems or structures loaded statically and dynamically. In the presence of these responses, the student is asked to compare them with those obtained by theoretical models that students already have enough knowledge to develop. The explanation of the differences between the results obtained by both routes is one of the important tasks that the student should be able to accomplish. As the various studies are carried out in the group, it is important that the student can promote all their development work and criticism in a group environement.

General characterization





Responsible teacher

Pedro Samuel Gonçalves Coelho, Raquel Albuquerque Soares Brás de Almeida


Weekly - 4

Total - 59

Teaching language



The contents taught in this curricular unit (UC) have a strong connection to subjects previously taught in subjects in the area of ​​​​material resistance, dynamics of rigid bodies, and mechanical vibrations, that is, in the UCs of Applied Mechanics I and II (MA_I and MA_II), Solid Mechanics I and II (MS_I and MS_II) and very important in Mechanical Vibrations and Noise (VMR).

Students who previously enrolled in the UC of Vibrations and Mechanical Noises (VMR) and were considered “absent” or had an assessment of fewer than eight values should not enroll in this UC, because 75% of the experimental work that will carry out requires acquired knowledge in VMR.


Encyclopedie VISHAY d''Analyse des Contraintes" Ed da VISHAY Micromesures.

"Fundamentos de Extensometria Eléctrica" - A.P. Vale Urgueira FCT- 2003

"The Strain Gage Primer",  CC Perry, HR Lissner, McGraw Hill

"Dinâmica - Mecânica Vectorial para Engenheiros",  Beer and Johnston Mc Graw Hill 1998

RS Figliola, DE Beasley; "Theory and Design for Mechanical Measurements", John Wiley Sons

KG McConnell "Vibration Testing - Theory and Practice", John Wiley Sons

Maia et all, "Theoretical and Experimental Modal Analysis", RSP

JH Ginsberg "Mechanical and Structural Vibrations - Theory and Applications", JWS

Teaching method

The curricular unit consists of several modules taught in theoretical classes, some dealing with new material in the course and others making an interconnection of various subjects, however learned throughout the course. Essentially, the first module deals with the response measurement techniques using electrical strain gauges, the second considers the effect of the uncertainties of the equipment and the measurement chain on the final value that is intended to be obtained experimentally and in the third Practical models associated with various matters of rigid body dynamics and mechanical vibrations are developed. Students have to carry out several laboratory works, in groups, to present the respective reports, thus having the opportunity to develop the critical spirit of analysis of the results as well as teamwork.

Evaluation method

The evaluation understands the performance of all laboratory work (LW) and its reports that are subsequently subject to discussion with each group of students, the result of all LW should be positive. All LW has equal weight in the final average of each student. 

Subject matter

Experimental stress analysis: Basic principles of electrical extensometry and photoelasticity. Placement of strain gauges. Wheatstone Bridge. Rosette of extensions. of Stress concentration.

 Dynamics: Determination of the moments of inertia of rigid bodies from the use of the composite and bifilar pendulum.

 Mechanical Vibrations: Introduction to experimental modal analysis of vibratory systems. 

Data Acquisition Systems: Fundamentals of signal theory. Signal processing and conditioning. Transducers: force measurement; pressure; displacement; speed; acceleration; flow.


Programs where the course is taught: