Adaptive Lifting Index (aLI) for Real-Time Instrumental Biomechanical Risk Assessment: Concepts, Mathematics, and First Experimental Results.

When performing lifting tasks at work, the Lifting Index (LI) is widely used to prevent work-related low-back disorders, but it presents criticalities pertaining to measurement accuracy and precision. Wearable sensor networks, such as sensorized insoles and inertial measurement units, could improve biomechanical risk assessment by enabling the computation of an adaptive LI (aLI) that changes over time in relation to the actual method of carrying out lifting. This study aims to illustrate the concepts and mathematics underlying aLI computation and compare aLI calculations in real-time using wearable sensors and force platforms with the LI estimated with the standard method used by ergonomists and occupational health and safety technicians. To reach this aim, 10 participants performed six lifting tasks under two risk conditions. The results show us that the aLI value rapidly converges towards the reference value in all tasks, suggesting a promising use of adaptive algorithms and instrumental tools for biomechanical risk assessment.

Ergonomic human-robot collaboration in industry: A review.

In the current industrial context, the importance of assessing and improving workers' health conditions is widely recognised. Both physical and psycho-social factors contribute to jeopardising the underlying comfort and well-being, boosting the occurrence of diseases and injuries, and affecting their quality of life. Human-robot interaction and collaboration frameworks stand out among the possible solutions to prevent and mitigate workplace risk factors. The increasingly advanced control strategies and planning schemes featured by collaborative robots have the potential to foster fruitful and efficient coordination during the execution of hybrid tasks, by meeting their human counterparts' needs and limits. To this end, a thorough and comprehensive evaluation of an individual's ergonomics, i.e. direct effect of workload on the human psycho-physical state, must be taken into account. In this review article, we provide an overview of the existing ergonomics assessment tools as well as the available monitoring technologies to drive and adapt a collaborative robot's behaviour. Preliminary attempts of ergonomic human-robot collaboration frameworks are presented next, discussing state-of-the-art limitations and challenges. Future trends and promising themes are finally highlighted, aiming to promote safety, health, and equality in worldwide workplaces.

A Directional Vibrotactile Feedback Interface for Ergonomic Postural Adjustment.

The objective of this paper is to develop and evaluate a directional vibrotactile feedback interface as a guidance tool for postural adjustments during work. In contrast to the existing active and wearable systems such as exoskeletons, we aim to create a lightweight and intuitive interface, capable of guiding its wearers towards more ergonomic and healthy working conditions. To achieve this, a vibrotactile device called ErgoTac is employed to develop three different feedback modalities that are able to provide a directional guidance at the body segments towards a desired pose. In addition, an evaluation is made to find the most suitable, comfortable, and intuitive feedback modality for the user. Therefore, these modalities are first compared experimentally on fifteen subjects wearing eight ErgoTac devices to achieve targeted arm and torso configurations. The most effective directional feedback modality is then evaluated on five subjects in a set of experiments in which an ergonomic optimisation module provides the optimised body posture while performing heavy lifting or forceful exertion tasks. The results yield strong evidence on the usefulness and the intuitiveness of one of the developed modalities in providing guidance towards ergonomic working conditions, by minimising the effect of an external load on body joints. We believe that the integration of such low-cost devices in workplaces can help address the well-known and complex problem of work-related musculoskeletal disorders.

An Online Method to Detect and Locate an External Load on the Human Body with Applications in Ergonomics Assessment.

In this work, we propose an online method to detect and approximately locate an external load induced on the body of a person interacting with the environment. The method is based on a torque equilibrium condition on the human sagittal plane, which takes into account a reduced-complexity model of the whole-body centre of pressure (CoP) along with the measured one, and the vertical component of the ground reaction forces (vGRFs). The latter is combined with a statistical analysis approach to improve the localisation accuracy, (which is subject to uncertainties) to the extent of the industrial applications we target. The proposed technique eliminates the assumption of known contact position of an external load on the human limbs, allowing a more flexible online body-state tracking. The accuracy of the proposed method is first evaluated via a simulation study in which various contact points on different body postures are considered. Next, experiments on human subjects with three different contact locations applied to the human body are presented, revealing the validity of the proposed methodology. Lastly, its benefit in the estimation of human dynamic states is demonstrated. These results add another layer to the online human ergonomics assessment framework developed in our laboratory, extending it to more realistic and varying interaction conditions.

Mobilidade funcional em idosos institucionalizados e não institucionalizados / Functional mobility in institutionalized and non-institutionalized elderly

INTRODUÇÃO: Quedas são importante causa de morbidade e mortalidade na terceira idade, com consequências que vão desde pequenas lesões até a morte. A medida da mobilidade funcional pode ser usada para predizer o risco de quedas e para mensurar o resultado de intervenções que busquem reduzi-lo. OBJETIVOS: Avaliar e comparar uma medida de mobilidade funcional em idosos residentes na comunidade e em uma instituição de longa permanência para idosos (ILPI), e verificar sua relação com idade e sexo nos diferentes locais de moradia. MATERIAIS e MÉTODOS: Participaram deste estudo observacional, analítico e transversal, 413 idosos, sendo 72 institucionalizados (80,9 ± 8,1anos; 53 mulheres) e 341 da comunidade (69,8 ± 7,5 anos; 269 mulheres). Para avaliar o grau de mobilidade funcional, foi utilizado o teste do levantar e caminhar cronometrados (TUG). RESULTADOS: Não foi detectada diferença estatística entre as médias do TUG apresentadas pelos sexos, tanto na comunidade (p>0,05), quanto na ILPI (p>0,05). Homens e mulheres residentes na ILPI apresentaram média de TUG significativamente maior que homens e mulheres da comunidade (p<0,01). Foi detectada diferença significativa entre as médias de TUG, quando comparadas em termos de faixa etária (p=0,003). CONCLUSÃO: A mobilidade funcional é maior entre os idosos que residem na comunidade, os quais, portanto, apresentam menor risco de quedas. Homens e mulheres apresentam nível semelhante de desempenho na mobilidade funcional, a qual decresce com a idade, em todas as faixas etárias. Sugerem-se intervenções que auxiliem ambos os grupos a melhorarem sua mobilidade e, portanto, a diminuir o risco de quedas.

INTRODUCTION: Falls are a major cause of morbidity and mortality in old age, with consequences ranging from minor injuries to death. The measure of functional mobility can be used to predict the risk of falls and to measure the result of interventions that seek to reduce it. OBJECTIVES: To assess and compare a functional mobility measure in elderly people living in the community and in a long stay institution (LSI), and determine its relation to age and sex in the different places of residence. MATERIALS AND METHOD: This observational, analytical and cross-sectional study used data from two other observational studies carried out in the city of Porto Alegre, Brazil. A total of 413 elderly people took part in this study; out of those 72 were institutionalized (average age = 80.9 ± 8.1years) and 341 lived in the community (69.8 ± 7.5 years). The Timed Up and Go Test (TUG) was used to evaluate the degree of functional mobility. RESULTS: No statistical difference was found in the TUG mean values presented by the genders, both in the community (p>0.05) and in the LSI (p>0.05). Institutionalized men and women showed significantly higher TUG mean than those living in the community (p<0.01). A significant difference was detected between the TUG means, when compared in terms of age group (p = 0.003). CONCLUSION: Functional mobility decreases with age in men and women, but does not differ between the sexes. Elderly people living in the community were faster than the institutionalized ones and therefore had a lower risk of falls. It is clear that there is a need for interventions that help both groups improve their mobility and reduce the risk of falls.

Efeitos da mobilização neural em terra e na água: um estudo comparativo / Effects of neural mobilization on land and water: a comparative study

Durante a realização de testes neurodinâmicos existe uma atividade muscular protetora, que possui como objetivo evitar o alongamento neural excessivo. na imersão em águas aquecidas ocorre um relaxamento de tecidos moles, permitindo assim um aumento do arco de movimento. O objetivo do estudo foi verificar o ganho de amplitude de movimento (ADM) de cotovelo após a realização da técnica de mobilização neural em terra e na água, através do teste neurodinâmico "Upper Limb Tension Test" (ULTT1) para o nervo mediano, comparando os resultados obtidos. A amostra foi composta de 20 sujeitos. Estes realizaram a técnica de mobilização neural mantida por 3 minutos uma vez na água e outra em terra. Assim foi obtido o ganho da ADM de cotovelo pré e pós técnica em cada meio. A amostra apresentou uma melhora em relação à ADM de cotovelo tanto em terra quanto na água. 16 sujeitos apresentaram melhores na água e apenas 4 em terra. O ganho mediano da ADM de cotovelo na água foi de 23º enquanto em terra foi de 7º. Embora em ambos os meios ocorra uma melhora significativa da excursão neural (p<0,01), a técnica de mobilização neural possui uma efetividade maior quando realizada na água (p<0,01). Este estudo apresentou uma maior efetividade da técnica de mobilização neural realizada na água comparada com a realização em terra.

It is know that while neurodynamic tests are being realized, there is a muscle protector activity which avoids the exceeding neural prolongament. A relaxing on the soft tissues occurs with an immersion in warm water, permitting an increase of the movement arch. To verify the elbow movement amplitude gain after the realization of the neural mobilization technique in the earth and in the water, through the neurodynamic test for the median nerve "Upper Limb Tension Test" (ULTT1). The sample was formed of 20 people. The neural mobilizationa technique for 3 minutes once in the water and then in the earth. Thus it was obtained, in each environment, the elbow's amplitude gain before and after the technique, using a universal goniometer. The sample showed an improvement in elbow's amplitude as much in the earth as in the water. 16 people presented better results in the water and only 4 in the earth. The medium elbow's amplitude gain in the water was of 23º while in the earth it was of 7º. Although in both enviroments there are significant improvements of elbow's range of motion (P<0,01), the neural mobilization technique has a better effectiveness when realized in the water (P<0,01). This research showed better effectivenes of the neural mobilization technique realized in the water in comparison with the one realized in the earth.