Analysis of required coefficient of friction in running and walking

Vidal, Andrea Brugnoli; Monezi, Lucas Antônio; Sarro, Karine Jacon; Barros, Ricardo Machado Leite de

doi:10.1080/14763141.2019.1601251

Cited by 5 publications

(4 citation statements)

References 30 publications

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“…Recreational running is becoming an increasingly popular pastime [ 1 ], with approximately 15% and 70% of amateur athletes currently engaging in this activity in the United Kingdom and the United States, respectively [ 2 , 3 ]. Various studies have shown that 50% of runners suffer an injury each year [ 4 ], although there are discrepancies in the literature, due to incidence values that vary from 18.2% to 92.4% [ 5 ] and reported prevalence ranging from 46% to 90% among amateur runners [ 6 , 7 ].…”

Section: Introductionmentioning

confidence: 99%

Wearable Sensors Detect Differences between the Sexes in Lower Limb Electromyographic Activity and Pelvis 3D Kinematics during Running

Moltó

Pardo

Cuenca

et al. 2020

Sensors

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Each year, 50% of runners suffer from injuries. Consequently, more studies are being published about running biomechanics; these studies identify factors that can help prevent injuries. Scientific evidence suggests that recreational runners should use personalized biomechanical training plans, not only to improve their performance, but also to prevent injuries caused by the inability of amateur athletes to tolerate increased loads, and/or because of poor form. This study provides an overview of the different normative patterns of lower limb muscle activation and articular ranges of the pelvis during running, at self-selected speeds, in men and women. Methods: 38 healthy runners aged 18 to 49 years were included in this work. We examined eight muscles by applying two wearable superficial electromyography sensors and an inertial sensor for three-dimensional (3D) pelvis kinematics. Results: the largest differences were obtained for gluteus maximus activation in the first double float phase (p = 0.013) and second stance phase (p = 0.003), as well as in the gluteus medius in the second stance phase (p = 0.028). In both cases, the activation distribution was more homogeneous in men and presented significantly lower values than those obtained for women. In addition, there was a significantly higher percentage of total vastus medialis activation in women throughout the running cycle with the median (25th–75th percentile) for women being 12.50% (9.25–14) and 10% (9–12) for men. Women also had a greater range of pelvis rotation during running at self-selected speeds (p = 0.011). Conclusions: understanding the differences between men and women, in terms of muscle activation and pelvic kinematic values, could be especially useful to allow health professionals detect athletes who may be at risk of injury.

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Section: Introductionmentioning

confidence: 99%

Wearable Sensors Detect Differences between the Sexes in Lower Limb Electromyographic Activity and Pelvis 3D Kinematics during Running

Moltó

Pardo

Cuenca

et al. 2020

Sensors

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“…23 One way to describe the friction force or estimate the magnitude of the resistance of the relative movement between bodies, is through the coefficient of friction (COF), which can be static (ls) or dynamic (ld). 19,24,25 Some researches showed that the friction coefficient of the printed parts varies according to parameters such as: building orientation, layer thickness, raster angle, air gap, and infill density. 23,[26][27][28] The adjustment of the printing variables has an impact on the improvement of the characteristics of the parts, such as the smoothing of the surfaces-that is, reducing the roughness and the magnitude of the staircase effect 23 -and minimizing the porosity, 28 which generates a decrease in the COF.…”

Section: Introductionmentioning

confidence: 99%

Effect of the angle of the laid-up filaments on the surfaces on the coefficient of static friction between parts manufactured by extrusion-based 3D printing

Santana

Alves

Netto

2020

Proceedings of the Institution of Mechanical Engineers, Part L:

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Three-dimensional printers, particularly the extrusion-based ones, are driving a global academic, industrial, and social revolution. The accessibility of the technology has allowed a number of enthusiasts and scientists to dedicate efforts to improve the technical properties of the parts produced. However, there is little literature on the measurement of the coefficient of friction, especially the static one, between a pair of printed parts. In this sense, an investigation was carried out in two stages, in which at first the static coefficient of friction was measured, through a simple apparatus based on the concept of the inclined plane, varying the angle of the filaments laid up on the surfaces of the two parts in contact. The parameter was analyzed at three levels—0°, 45°, and 90°—in components manufactured in poly(lactic acid) and poly(ethylene glycol terephthalate). In the second part of the research, a case study was carried out to test and validate the effects of the best and worst friction conditions on the behavior of the insertion force of snap-fit connections. The results obtained show a significant influence of the filament angle in the interaction between two printed parts. Combinations of contact with different angles decrease the static coefficient of friction, while faces with equal angles tend to increase the magnitude of the response, especially if the arrangement of the filaments allows a fit of the surfaces opposite to sliding. The static coefficient of friction of poly(lactic acid) varied from 0.12 to 0.38, while the static coefficient of friction of poly(ethylene glycol terephthalate) varied from 0.13 to 0.21. The responses of the inclined plane test allowed to predict the behavior of the insertion force and plan the design of quick fittings.

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“…Four of these force actuators are organized into pairs such that normal forces f n and their corresponding friction forces μ f n can be generated in a positive or negative (antero-posterior or medio-lateral) direction corresponding to the foot contact planes. The friction coefficient μ was set to 0.5, which corresponds to the coefficient measured during walking ( Vidal et al, 2021 ). The last force actuator, aligned with the vertical axis, can generate only a force normal to the surface ( Figure 3B ).…”

Section: Methodsmentioning

confidence: 99%

Prediction of ground reaction forces and moments during walking in children with cerebral palsy

Kloeckner

Visscher

Taylor

et al. 2023

Front. Hum. Neurosci.

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IntroductionGait analysis is increasingly used to support clinical decision-making regarding diagnosis and treatment planning for movement disorders. As a key part of gait analysis, inverse dynamics can be applied to estimate internal loading conditions during movement, which is essential for understanding pathological gait patterns. The inverse dynamics calculation uses external kinetic information, normally collected using force plates. However, collection of external ground reaction forces (GRFs) and moments (GRMs) can be challenging, especially in subjects with movement disorders. In recent years, a musculoskeletal modeling-based approach has been developed to predict external kinetics from kinematic data, but its performance has not yet been evaluated for altered locomotor patterns such as toe-walking. Therefore, the goal of this study was to investigate how well this prediction method performs for gait in children with cerebral palsy.MethodsThe method was applied to 25 subjects with various forms of hemiplegic spastic locomotor patterns. Predicted GRFs and GRMs, in addition to associated joint kinetics derived using inverse dynamics, were statistically compared against those based on force plate measurements.ResultsThe results showed that the performance of the predictive method was similar for the affected and unaffected limbs, with Pearson correlation coefficients between predicted and measured GRFs of 0.71–0.96, similar to those previously reported for healthy adults, despite the motor pathology and the inclusion of toes-walkers within our cohort. However, errors were amplified when calculating the resulting joint moments to an extent that could influence clinical interpretation.ConclusionTo conclude, the musculoskeletal modeling-based approach for estimating external kinetics is promising for pathological gait, offering the possibility of estimating GRFs and GRMs without the need for force plate data. However, further development is needed before implementation within clinical settings becomes possible.

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Analysis of required coefficient of friction in running and walking

Cited by 5 publications

References 30 publications

Wearable Sensors Detect Differences between the Sexes in Lower Limb Electromyographic Activity and Pelvis 3D Kinematics during Running

Wearable Sensors Detect Differences between the Sexes in Lower Limb Electromyographic Activity and Pelvis 3D Kinematics during Running

Effect of the angle of the laid-up filaments on the surfaces on the coefficient of static friction between parts manufactured by extrusion-based 3D printing

Prediction of ground reaction forces and moments during walking in children with cerebral palsy

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