Design and Assist-as-Needed Control of Flexible Elbow Exoskeleton Actuated by Nonlinear Series Elastic Cable Driven Mechanism

Exoskeletons can assist the daily life activities of the elderly with weakened muscle strength, but traditional rigid exoskeletons bring parasitic torque to the human joints and easily disturbs the natural movement of the wearer’s upper limbs. Flexible exoskeletons have more natural human-machine interaction, lower weight and cost, and have great application potential. Applying assist force according to the patient’s needs can give full play to the wearer’s remaining muscle strength, which is more conducive to muscle strength training and motor function recovery. In this paper, a design scheme of an elbow exoskeleton driven by flexible antagonistic cable actuators is proposed. The cable actuator is driven by a nonlinear series elastic mechanism, in which the elastic elements simulate the passive elastic properties of human skeletal muscle. Based on an improved elbow musculoskeletal model, the assist torque of exoskeleton is predicted. An assist-as-needed (AAN) control algorithm is proposed for the exoskeleton and experiments are carried out. The experimental results on the experimental platform show that the root mean square error between the predicted assist torque and the actual assist torque is 0.00226 Nm. The wearing experimental results also show that the AAN control method designed in this paper can reduce the activation of biceps brachii effectively when the exoskeleton assist level increases.

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AnkFall—Falls, Falling Risks and Daily-Life Activities Dataset with an Ankle-Placed Accelerometer and Training Using Recurrent Neural Networks

Sensors ◽

10.3390/s21051889 ◽

2021 ◽

Vol 21 (5) ◽

pp. 1889

Author(s):

Francisco Luna-Perejón ◽

Luis Muñoz-Saavedra ◽

Javier Civit-Masot ◽

Anton Civit ◽

Manuel Domínguez-Morales

Keyword(s):

Elderly Person ◽

Fall Detection ◽

The Elderly ◽

Daily Life Activities ◽

Learning Classifier ◽

The People ◽

Activity Types ◽

Remote Monitoring Systems ◽

Secondary Study

Falls are one of the leading causes of permanent injury and/or disability among the elderly. When these people live alone, it is convenient that a caregiver or family member visits them periodically. However, these visits do not prevent falls when the elderly person is alone. Furthermore, in exceptional circumstances, such as a pandemic, we must avoid unnecessary mobility. This is why remote monitoring systems are currently on the rise, and several commercial solutions can be found. However, current solutions use devices attached to the waist or wrist, causing discomfort in the people who wear them. The users also tend to forget to wear the devices carried in these positions. Therefore, in order to prevent these problems, the main objective of this work is designing and recollecting a new dataset about falls, falling risks and activities of daily living using an ankle-placed device obtaining a good balance between the different activity types. This dataset will be a useful tool for researchers who want to integrate the fall detector in the footwear. Thus, in this work we design the fall-detection device, study the suitable activities to be collected, collect the dataset from 21 users performing the studied activities and evaluate the quality of the collected dataset. As an additional and secondary study, we implement a simple Deep Learning classifier based on this data to prove the system’s feasibility.

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A Bibliometric Analysis of Human-Machine Interaction Methodology for Electric-Powered Wheelchairs Driving from 1998 to 2020

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18147567 ◽

2021 ◽

Vol 18 (14) ◽

pp. 7567

Author(s):

Xiaochen Zhang ◽

Lanxin Hui ◽

Linchao Wei ◽

Fuchuan Song ◽

Fei Hu

Keyword(s):

The Elderly ◽

Research Field ◽

Future Research ◽

Human Machine Interaction ◽

Research Directions ◽

The Past ◽

Power Wheelchairs ◽

The Disabled ◽

Future Research Directions ◽

Machine Interaction

Electric power wheelchairs (EPWs) enhance the mobility capability of the elderly and the disabled, while the human-machine interaction (HMI) determines how well the human intention will be precisely delivered and how human-machine system cooperation will be efficiently conducted. A bibliometric quantitative analysis of 1154 publications related to this research field, published between 1998 and 2020, was conducted. We identified the development status, contributors, hot topics, and potential future research directions of this field. We believe that the combination of intelligence and humanization of an EPW HMI system based on human-machine collaboration is an emerging trend in EPW HMI methodology research. Particular attention should be paid to evaluating the applicability and benefits of the EPW HMI methodology for the users, as well as how much it contributes to society. This study offers researchers a comprehensive understanding of EPW HMI studies in the past 22 years and latest trends from the evolutionary footprints and forward-thinking insights regarding future research.

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How to simultaneously optimize muscle strength, power, functional capacity, and cardiovascular gains in the elderly: an update

AGE ◽

10.1007/s11357-012-9503-x ◽

2013 ◽

Vol 35 (6) ◽

pp. 2329-2344 ◽

Cited By ~ 31

Author(s):

Cadore EL ◽

Izquierdo M

Keyword(s):

Muscle Strength ◽

Functional Capacity ◽

The Elderly

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A Power-Assisted Cart with the Optimal Assistance Ratio and Disturbance Observer-Based Methods for Walking Assistance Applications

Applied Sciences ◽

10.3390/app11031079 ◽

2021 ◽

Vol 11 (3) ◽

pp. 1079

Author(s):

Xianglong Wan ◽

Jiaxin Ma ◽

Yichi Zhang ◽

Takahiro Endo ◽

Fumitoshi Matsuno

Keyword(s):

Healthy Subjects ◽

Disturbance Observer ◽

The Elderly ◽

Operational Efficiency ◽

Motor Output ◽

Experimental Results ◽

Control Methods ◽

Road Surfaces

In this paper, we propose two control methods for driving a power-assisted cart made for walking assistance for the elderly. The optimal assistance ratio (OAR) and disturbance observer-based (DOB) methods properly adjust the motor output of the cart with high operational efficiency in response to changes in the environment. Healthy subjects walked with the cart on several road surfaces under various conditions, and the experimental results indicate the high operational efficiency of the two proposed methods. Meanwhile, their drawbacks are also discussed herein. The two methods can be used separately or combined according to the application. The OAR method is more suitable for indoor use, while the DOB method is applicable for outdoor applications. Combining these two methods could overcome the mentioned drawbacks.

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Comparison of Times of Synchronization of Chaotic Burke-Shaw Attractor with Active Control and Integer and Optimum Fractional-Order Pecaro Carroll Method

10.21203/rs.3.rs-263593/v1 ◽

2021 ◽

Author(s):

Ali Durdu ◽

Yılmaz Uyaroğlu

Keyword(s):

Active Control ◽

Fractional Order ◽

Chaotic Attractor ◽

Secure Communication ◽

Chaotic Systems ◽

Control Method ◽

Initial Conditions ◽

Data Communication ◽

Experimental Results ◽

Active Control Method

Abstract Many studies have been introduced in the literature showing that two identical chaotic systems can be synchronized with different initial conditions. Secure data communication applications have also been made using synchronization methods. In the study, synchronization times of two popular synchronization methods are compared, which is an important issue for communication. Among the synchronization methods, active control, integer, and fractional-order Pecaro Carroll (P-C) method was used to synchronize the Burke-Shaw chaotic attractor. The experimental results showed that the P-C method with optimum fractional-order is synchronized in 2.35 times shorter time than the active control method. This shows that the P-C method using fractional-order creates less delay in synchronization and is more convenient to use in secure communication applications.

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Muscle strength cut-points for metabolic syndrome detection among adults and the elderly from Brazil

Applied Physiology Nutrition and Metabolism ◽

10.1139/apnm-2020-0758 ◽

2021 ◽

Vol 46 (4) ◽

pp. 379-388

Author(s):

Tiago Rodrigues de Lima ◽

David Alejandro González-Chica ◽

Eleonora D’Orsi ◽

Xuemei Sui ◽

Diego Augusto Santos Silva

Keyword(s):

Metabolic Syndrome ◽

Muscle Strength ◽

Lifestyle Modification ◽

Handgrip Strength ◽

Area Under The Curve ◽

Roc Curves ◽

The Elderly ◽

Youden Index ◽

Cross Sectional ◽

Cut Points

We aimed to determine cut-points for muscle strength based on metabolic syndrome diagnosis. This cross-sectional analysis comprised data from 2 cohorts in Brazil (EpiFloripa Adult, n = 626, 44.0 ± 11.1 years; EpiFloripa Aging, n = 365, 71.6 ± 6.1 years). Metabolic syndrome was assessed by relative handgrip strength (kgf/kg). Metabolic syndrome was defined as including ≥3 of the 5 metabolic abnormalities according to the Joint Interim Statement. Optimal cut-points from Receiver Operating Characteristic (ROC) curves were determined. Adjusted logistic regression was used to test the association between metabolic syndrome and the cut-points created. The cut-point identified for muscle strength was 1.07 kgf/kg (Youden index = 0.310; area under the curve (AUC)) = 0.693, 95% CI 0.614–0.764) for men and 0.73 kgf/kg (Youden index = 0.481; AUC = 0.768, 95% confidence interval (CI) = 0.709–0.821) for women (age group 25 to < 50 years). The best cut-points for men and women aged 50+ years were 0.99 kgf/kg (Youden index = 0.312; AUC = 0.651; 95% CI = 0.583–0.714) and 0.58 kgf/kg (Youden index = 0.378; AUC = 0.743; 95% CI = 0.696–0.786), respectively. Cut-points derived from ROC analysis have good discriminatory power for metabolic syndrome among adults aged 25 to <50 years but not for adults aged 50+ years. Novelty: First-line management recommendation for metabolic syndrome is lifestyle modification, including improvement of muscle strength. Cut-points for muscle strength levels according to sex and age range based on metabolic syndrome were created. Cut-points for muscle strength can assist in the identification of adults at risk for cardiometabolic disease.

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Novel fractional hybrid impedance control of series elastic muscle-tendon actuator

Industrial Robot the international journal of robotics research and application ◽

10.1108/ir-10-2020-0236 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Mohammad Javad Fotuhi ◽

Zafer Bingul

Keyword(s):

Contact Stress ◽

Impedance Control ◽

Robustness Analysis ◽

Simulation Models ◽

Experimental Results ◽

Uncertain Environments ◽

Content Type ◽

Force Tracking ◽

Comparative Results ◽

Series Elastic

Purpose This paper aims to develope a novel fractional hybrid impedance control (FHIC) approach for high-sensitive contact stress force tracking control of the series elastic muscle-tendon actuator (SEM-TA) in uncertain environments. Design/methodology/approach In three different cases, the fractional parameters of the FHIC were optimized with the particle swarm optimization algorithm. Its adaptability to the pressure of the sole of the foot on real environments such as grass (soft), carpet (medium) and solid floors (hard) is far superior to traditional impedance control. The main aim of this paper is to derive the dynamic simulation models of the SEM-TA, to develop a control architecture allowing for high-sensitive contact stress force control in three cases and to verify the simulation models and the proposed controller with experimental results. The performance of the optimized controllers was evaluated according to these parameters, namely, maximum overshoot, steady-state error, settling time and root mean squared errors of the positions. Moreover, the frequency robustness analysis of the controllers was made in three cases. Findings Different simulations and experimental results were conducted to verify the control performance of the controllers. According to the comparative results of the performance, the responses of the proposed controller in simulation and experimental works are very similar. Originality/value Origin approach and origin experiment.

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PENGARUH SENAM JANTUNG SEHAT SERI-I TERHADAP DAYA TAHAN JANTUNG-PARU, KEKUATAN OTOT DAN KADAR TNF-? PLASMA PADA LANJUT USIA

JURNAL ILMU FAAL OLAHRAGA INDONESIA ◽

10.51671/jifo.v1i1.37 ◽

2019 ◽

Vol 1 (1) ◽

pp. 1

Author(s):

Ajeng Fitria ◽

Leonardo Lubis ◽

Ambrosius Purba

Keyword(s):

Muscle Strength ◽

Health Workers ◽

The Elderly ◽

Moderate Intensity ◽

P Value ◽

Back Muscle ◽

Back Muscle Strength ◽

Shoulder Muscles ◽

Before And After ◽

Post Test

The increasing number of elderly and elderly life expectancy is a challenge for health workers. Decreased cardiac endurance, muscle strength and increased incidence of inflammation will occur in the elderly as we get older. health cardio exercises series-I is an aerobic exercise that has moderate intensity and is carried out for 30 minutes, research is needed to analyze the effect on cardiac endurance, muscle strength and decrease plasma TNF-? levels in the elderly. Research design with experimental method, pre-test and post-test design approach. The study was conducted for 4 weeks on 25 samples which were divided into 3 groups of frequency of health cardio exercises series-I to measure endurance of the heart. A 6-minute road test and muscle strength were used for hand grip strength dynamometer, test back and leg dynamometer. Measurement of plasma TNF-? levels is carried out using the Elisa method. The data was then analyzed using paired t-test to see differences before and after health cardio exercises series-I. The results showed health cardio exercises series-I performed 3x / mg can increase the heart's endurance compared to the frequency of 4x / mg and 5x / mg (-16.11 vs 15.62 vs -47.62 meters). health cardio exercises series-I frequency of 3x / mg and 4x / mg can increase back muscle strength (p-value = 0.019, p <0.05) and the frequency of 5x / mg can increase the strength of attractive shoulder muscles. (p-value = 0.033, p <0.05). Health cardio exercises series-I performed 3x / mg, 4x / mg and 5x / mg did not have a significant effect on plasma TNF-? protein expression in the elderly (0.506 vs 0.856 vs. 0.382, p <0.05). It is suggested that the elderly can do I-1 series heart exercise with a frequency of 3x / mg to increase the heart's lung endurance and back muscle strength, a health cardio exercises series-I 4x / mg series to increase muscle strength of the back back, a series of health cardio exercises series-I frequency of 5x / mg to increase attractive shoulder muscle strength.

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The influence of the practice of physical activity on the quality of life, muscle strength, balance, and physical ability in the elderly

Revista Brasileira de Geriatria e Gerontologia ◽

10.1590/s1809-98232013000100012 ◽

2013 ◽

Vol 16 (1) ◽

pp. 117-126 ◽

Cited By ~ 1

Author(s):

Mariana Martinez Orlando ◽

Maria Stella Peccin da Silva ◽

Império Lombardi Junior

Keyword(s):

Quality Of Life ◽

Physical Activity ◽

Muscle Strength ◽

The Elderly ◽

Physical Capacity ◽

Cross Sectional ◽

Elderly Individuals ◽

Assess Quality ◽

The City

INTRODUCTION: Ageing has become a huge public health challenge due to the need to find solutions for improving quality of life. OBJECTIVE: This study aimed to assess quality of life, muscle strength, balance and physical capacity among elderly practitioners and non-practitioners of physical activity. MATERIALS AND METHODS: An observational, cross-sectional study was carried out involving 74 elderly individuals in the city of Santos (state of São Paulo, Brazil), divided into two groups: practitioners and non-practitioners of physical activity. The International Physical Activity Questionnaire was used for the classification of the participants. The generic SF-36 questionnaire was used to assess quality of life. The Berg scale was used for the analysis of balance. Dynamometry was used for the muscle strength test. The six-minute walk test was used for the assessment of physical capacity. RESULTS: Significant differences were found between elderly practitioners and non-practitioners of physical activity regarding quality of life (p = 0.001), muscle strength (p = 0.001), balance (p = 0.001) and physical capacity (p = 0.001). The data also showed that aspects of quality of life were strongly correlated with physical capacity among the non-practitioners of physical activity (r = 0.741). CONCLUSION: Elderly individuals in the city of Santos (Brazil) who practice physical activity have better quality of life, muscle strength, physical capacity and balance in comparison to those who do not practice physical activity.

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