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Publicações

Publicações por Carlos Barbosa Rodrigues

2017

Consistency of surface electromyography assessment at lower limb selected muscles during vertical countermovement

Autores
Rodrigues, C; Correia, M; Abrantes, JMCS; Nadal, J; Benedetti Rodrigues, MAB;

Publicação
Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBS

Abstract
Given the difficulty of invasive methods to assess muscle action during natural human movement, surface electromyography (sEMG) has been increasingly used to capture muscle activity in relation to kinesiological analysis of specific tasks. Isolated isometric, concentric and eccentric forms of muscle action have been receiving the most attention for research purposes. Nevertheless natural muscle action frequently involves the use of a preceding eccentric muscle action as a form of potentiation of immediate muscle concentric action, in what is designated as muscle stretch-shortening cycle (SSC). The most frequently applied protocols for the evaluation of SSC on vertical jumps are by virtue of their reproducibility and control of experimental conditions, squat jump (SJ) without countermovement (CM), countermovement jump (CMJ) with long CM and drop jump (DJ) with short CM. The methods used to extract information and relationship of the captured signals also present a high diversity, with the question about the consistency of the methods and obtained results. The objective of this study is to evaluate the consistency of the analysis and results by applying different EMGs signal analysis techniques related to strategic muscle groups of the lower limbs at different countermovement evaluated in vertical jumps. Raw sEMG signals of 5 lower limb muscles of 6 subjects during SJ, CMJ and DJ were rectified, filtered and obtained their envelope, and then correlated (CR) for detection of synergistic, agonist and antagonist activity, applied principal component analysis (PCA) for the detection of uncorrelated components explaining maximum variability and normalized cross-correlation (CCRN) for detection of maximum correlations and time lag. CR of EMG envelopes presented higher coactivities (CoA) in DJ relative to SJ and these CoA superior to CMJ with greater synergy in DJ relative to SJ and CMJ that present several loop cycles corresponding to time lag of activity. CCRN of the EMG envelopes presented also higher CoA in DJ when compared to SJ and both higher CoA to CMJ. PCA allowed to detect a principal component (PC) explaining 92.2% of the variability of EMG in DJ, 90.6% in SJ and 78.7% in CMJ, the second PC responsible for the explanation of 4.9% variability in DJ, 6.7% in SJ and 15.3% in CMJ. © 2017 IEEE.

2015

Smartphone Robot for High School Students: RobHiSS

Autores
Martins, B; Costa, A; Caetano, C; Rodrigues, C; Ruao, G; Lopes, I; Aguiar, J; Sousa, P; Silva, P; Correia, T; Sousa, A;

Publicação
PROCEEDINGS OF THE 2015 10TH IBERIAN CONFERENCE ON INFORMATION SYSTEMS AND TECHNOLOGIES (CISTI 2015)

Abstract
This project arose from the absence in the market of a modular smartphone controlled robot capable of encouraging high school students to program and apply the physics and math's knowledge learned into it. Therefore this project's intention was to study the best way to develop a do-it-yourself (DIY) cost effective robot using only components off the shelf (COTS) and benefit from the omnipresence of smartphones. With the objective of making this robot attractive to anyone with low programming skills, it was important to make it configurable in an easy to understand language and a simple user interface, like the ones provided by Scratch and the MIT AppInventor2. The functional, physical and non-functional requirements for this robot and the free software developed are presented and validated attesting that this project was successfully completed.

2018

Innovative analysis of 3D pelvis coordination on modified gait mode

Autores
Rodrigues, C; Correia, MV; Abrantes, JMCS; Nadal, J; Rodrigues, MAB;

Publicação
Lecture Notes in Computational Vision and Biomechanics

Abstract
This study presents innovative analysis at the time, frequency and phase domain of the pelvis angular oscillation at transverse (T), sagittal (S) and coronal (C) planes, assessing its coordination during stiff knee gait (SKG) and slow running (SR) comparing it to normal gait (NG). Case study is considered of an adult male 70 kg mass and 1.86 m height. Computer vision is used with 8 Qualysis 100 Hz cameras tracking position of right and left anterior and posterior superior iliac spine (RAsis, LAsis, RPsis, LPsis) including one complete stride during NG, SKG and SR. 3D position coordinates are obtained from 2D image coordinate of multiple camera image using direct linear transformation (DLT). Inverse kinematics is performed using cartesian position data of RAsis, LAsis, RPsis, LPsis and scaled model to subject dimension. The angles, angular velocities and angular accelerations coordination of the pelvis oscillation at T, S, C planes were assessed using linear and cross correlation analysis (LCA, CCA), fast Fourier transform (FFT) and phase space analysis (PSA). Results point for important complementary analysis on entire series of time, frequency and phase analysis of human movement such as the pelvis coordination assessment on different gait modes. © 2018, Springer International Publishing AG.

2017

Validating subject multibody dynamics estimated action with measured SEMG at lower limb muscles on different gait modes

Autores
Rodrigues, C; Correia, M; Abrantes, J;

Publicação
Proceedings of the 8th ECCOMAS Thematic Conference on MULTIBODY DYNAMICS 2017, MBD 2017

Abstract
This study presents and applies a quantitative metric, based on entire time series of measured surface electromyography (sEMG) from selected lower limb muscles to validate multibody dynamics (MBD) estimated action of the same subject muscles during modified gait, stiff knee gait (SKG) and slow running (SR) in relation to normal gait (NG). MBD is being increasingly applied for estimation of internal actions according to difficulty of its direct measurements under natural conditions of movement and the importance of this estimation for prevention, diagnosis and treatment planning of specific subject skeletal and neuromuscular diseases. Inverse kinematics and inverse dynamics from position and force data have been used to estimate internal joint force moments, with muscle grouping and optimization techniques applied along with musculoskeletal model for estimation of muscle action. Nevertheless kinematic and kinetic input data of human movement must be accurate and employed model for simulation must be personalized to subject, task and moment of application. Also the results provided by the simulation with the musculoskeletal model must be compared with measured results for validation. Comparative analysis of kinematic and kinetic input data of human lower limbs is performed during modified gait modes and a personalized musculoskeletal model employed for MBD estimation of muscle actions and compare estimated muscle actions with measured sEMG of selected muscles on different gait modes, SKG and SR in relation to those registered at NG. The results from quantitative metrics followed qualitative agreement from visual inspection with better agreement between processed sEMG and MBD muscle estimated activity on phase metric than at magnitude, and combined metric presenting overall better agreement at NG and SKG than at SR, pointing to higher ability of the model to predict muscle force patterns in agreement with measured sEMG activity at NG and SKG than at SR and the need to improve model predictions for SR. Applied technique presents as a reproducible quantitative metric based on entire time series, both magnitude and phase, overcoming qualitative and subjective comparing by the observer, reducing time consuming and allowing increase at the number of automatic validation of MBD muscle action estimation.

2018

Generalized Lower Limb Joint Angular Phase Space Analysis of Subject Specific Normal and Modified Gait

Autores
Rodrigues, C; Correia, M; Abrantes, JMCS; Benedetti Rodrigues, MA; Nadal, J;

Publicação
2018 40th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC)

Abstract

2019

Combined phase and magnitude metric for validation of lower limb multibody dynamics muscle action with sEMG

Autores
Rodrigues, C; Correia, M; Abrantes, J; Nadal, J; Benedetti, M;

Publicação
IFMBE Proceedings

Abstract
This study presents and applies combined phase and magnitude metrics for validation of multibody dynamics (MBD) estimated muscle actions with simultaneous registered sEMG of lower limb muscles. Subject-specific tests were performed for acquisition of ground reaction forces and kinematic data from joint reflective markers during NG, SKG and SR. Inverse kinematics and dynamics was performed using AnyBody musculoskeletal personalized modeling and simulation. MBD estimated muscle activity (MA) of soleus medialis (SM) and tibialis anterior (TA) were compared on phase, magnitude and combined metric with simultaneous acquisition of sEMG for the same muscles. Results from quantitative metrics presented better agreement between MDB MA and sEMG on phase (P) than on magnitude (M) with combined (C) metric following the same pattern as the magnitude. Soleus medialis presented for specific subject lower P and M error on NG and SKG than at SR with similar P errors for tibialis anterior and higher error on M for TA at NG and SKG than SR. Separately and combined quantitative metrics of phase and magnitude presents as a suitable tool for comparing measured sEMG and MBD estimated muscle activities, contributing to overcome qualitative and subjective comparisons, need for intensive observer supervision, low reproducibility and time consuming. © Springer Nature Singapore Pte Ltd. 2019.

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