This paper presents a practical framework and its applications of motion tracking algorithms applied to structural dynamics. Tracking points (“features”) across multiple images are a fundamental operation in many computer vision applications. The aim of this work is to show the capability of computer vision (CV) for estimating the dynamic characteristics of two mechanical systems using a noncontact, markerless, and simultaneous single input multiple output analysis. Kanade–Lucas–Tomasi trackers are used as virtual sensors on mechanical systems’ video from a high speed camera. First we introduce the paradigm of virtual sensors in the field of modal analysis using video processing. To validate our method, a simple experiment is proposed: an Oberst beam test with harmonic excitation (mode 1). Then with the example of a helicopter blade, frequency response functions’ (FRFs) reconstruction is carried out by introducing several signal processing enhancements (filtering and smoothing). The CV experimental results (frequencies and mode shapes) are compared with the classical modal approach and the finite element model (FEM) showing high correlation. The main interest of this method is that displacements are simply measured using only video at fps respecting the Nyquist frequency.

Motions of the temporomandibular joint (TMJ) involve both translation and rotation; however, there may be substantial variations from one human to another, and these variations present significant difficulties when designing TMJ prostheses. The disc–condyle glides along the temporal bone and the condyle centre describe a curve that depends on the individual morphology. This study analyses disc–condyle rotatory and translatory displacements moving all along the temporal bone facets which are mainly composed of two areas: the articular tubercle slope (ATS) and the preglenoid plane separated by the articular tubercle crest. Displacements were quantified using 3D video analysis, and this technique was computer-assisted. From a population of 32 volunteers, we were able to establish a correlation between the kinematic characteristics of the joint and the disc–condyle trajectories. This study quantifies the geometrical characteristics of the ATS and their inter-individual variations, which are useful in TMJ prosthesis design.

This article presents a basic experimental technique and simplified finite element (FE)-based models for the detection, localization, and quantification of impact damage in composite beams around the barely visible impact damage level. Detection of damage is carried out by shift in modal parameters. Localization of damage is done by a topology optimization tool, which showed that correct damage locations can be found rather efficiently for low-level damage. The novelty of this article is that we develop an all in one package dedicated to impact identification by modal analysis. The damaged zones in the FE models are updated by reducing the most sensitive material property, in order to improve the experimental/ numerical correlation of the frequency response functions. These approximate damage models (in terms of equivalent rigidity) give us a simple degradation factor that can serve as a warning regarding the safety of the structure.