Examination and comparison of different methods to model closed loop kinematic chains using Lagrangian formulation with cut joint, clearance joint constraint and elastic joint approaches

This work aims at presenting, in a comprehensive manner, several approaches to model and simulate closed loop topologies using the classical Lagrangian formulation. One of the great advantages of the Lagrangian approach is its simplicity and easiness of obtaining the equations of motion. However, a critical aspect arises when the mechanical systems include closed loop topologies, since the process of deriving the equations of motion becomes a complex task. The key point of the present study is to convert the closed loop nature into open systems, which ultimately simplifies the modeling process when the Lagrangian formulation is utilized. For this purpose, three different methods are considered, namely those based on the cut joint approach, the clearance joint constraint model, and the elastic joint formulation are used. In the sequel of this process, a slider-crank mechanism is utilized as a demonstrative application example, and the main results are compared with those obtained with the well-established Newton-Euler method for constrained multibody systems. Moreover, this example allows the comparison of the main characteristics and peculiarities of the described approaches.This work has been supported by Portuguese Foundation for Science and Technology, under the national support to R&D units grant, with the reference project UIDB/04436/2020 and UIDP/04436/2020, as well as through IDMEC, under LAETA, project UIDB/50022/202

Estimating anatomically plausible segment orientations using a kinect one sensor

Abstract in proceedings of the Fourth International Congress of CiiEM: Health, Well-Being and Ageing in the 21st Century, held at Egas Moniz’ University Campus in Monte de Caparica, Almada, from 3–5 June 2019.This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.info:eu-repo/semantics/publishedVersio

Aprendizagem da Língua Gestual Portuguesa como M2: contributos da análise cinemática na identificação de possíveis erros fonológicos no parâmetro movimento

info:eu-repo/semantics/publishedVersio

On the modeling of biomechanical systems for human movement analysis: a narrative review

The rising importance of movement analysis led to the development of more complex biomechanical models to describe in detail the human motion patterns. The models scaled from simplistic two-dimensional to three-dimensional representations of body including detailed joint, muscle, tendon, and ligament models. Different computational methodologies have been proposed to extend traditional kinematic and dynamic analysis to include not only the evaluation of muscle forces but also the action of the central nervous system. Hence, a large number of models varying in complexity and target application are available in literature. This narrative review aims to provide an overview of the modeling of biomechanical systems used for the analysis of human movement within the framework of multibody dynamics, for those enrolled in engineering, clinical, rehabilitation and sports applications. The review includes detailed and generic models, as well as the main methodologies applied to model muscle activation and contraction dynamics. Numerous skeletal, musculoskeletal and neuromusculoskeletal models with variable degrees of complexity, accuracy and computational efficiency were identified. An important remark is that the most suitable model depends on the study objectives, detail level of the depicted anatomical structures, target population or performed motion. Summarizing, biomechanical systems have evolved remarkably during the last decades. Such advances allowed to gain a deep knowledge on how the human nervous system controls the movement during different activities, which has been used not only to optimize motor performance but also to develop solutions that allow impaired people to regain motor function in cases of disability, among other applications.This work has been supported by Portuguese Founda tion for Science and Technology, under the national support to R&D units grant, with the reference project UIDB/04436/2020 and UIDP/04436/2020, as well as through IDMEC, under LAETA, Pro ject UIDB/50022/2020 and PTDC/CCI-COM/30274/2017. The second author expresses her gratitude to the Portuguese Foundation for Science and Technology through the PhD Grant (2021.04840.BD