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The purpose of this paper is to focus on an engineering application of the vertebrate musculoskeletal system. The musculoskeletal system has unique mechanisms such as bi‐articular muscle, antagonistic muscle pairs and muscle‐tendon elasticity. The “artificial musculoskeletal system” is achieved through the use of the pneumatic artificial muscles. The study provides a novel method to describe the force property of the articulated mechanism driven by muscle actuator and a transmission.

A musculoskeletal system consists of multiple bodies connected together with rotational joints and driven by mono‐ and bi‐articular actuators. The paper analyzes properties of the musculoskeletal system with statically calculated omni‐directional output forces. A set of experiments has been performed to demonstrate the physical ability of the musculoskeletal robot.

A method to design a musculoskeletal system is proposed based on an analysis of the profile of convex polygon of maximum output forces. The result shows that the well‐designed musculoskeletal system enables the legged robot to jump 0.6 m high and land softly from 1.0 m drop off.

The paper provides a design principle for a musculoskeletal robot. The musculoskeletal system is the bio‐inspired mechanism for all multi‐degrees‐of‐freedom articulated devices, and has the advantages of optimized actuator configuration and force control.

This study aims to improve the muscle model control performance of a tendon-driven musculoskeletal system (TDMS) to overcome disadvantages such as multisegmentation and strong coupling. An adaptive network controller (ANC) with a disturbance observer is established to reduce the modeling error of the musculoskeletal model and improve its antidisturbance ability.

In contrast to other control technologies adopted for musculoskeletal humanoids, which use geometric relationships and antagonist inhibition control, this study develops a method comprising of three parts. (1) First, a simplified musculoskeletal model is constructed based on the Taylor expansion, mean value theorem and Lagrange–d’Alembert principle to complete the decoupling of the muscle model. (2) Next, for this simplified musculoskeletal model, an adaptive neuromuscular controller is designed to acquire the muscle-activation signal and realize stable tracking of the endpoint of the muscle-driven robot relative to the desired trajectory in the TDMS. For the ANC, an adaptive neural network controller with a disturbance observer is used to approximate dynamical uncertainties. (3) Using the Lyapunov method, uniform boundedness of the signals in the closed-loop system is proved. In addition, a tracking experiment is performed to validate the effectiveness of the adaptive neuromuscular controller.

The experimental results reveal that compared with other control technologies, the proposed design techniques can effectively improve control accuracy. Moreover, the proposed controller does not require extensive considerations of the geometric and antagonistic inhibition relationships, and it demonstrates anti-interference ability.

Musculoskeletal robots with humanoid structures have attracted considerable attention from numerous researchers owing to their potential to avoid danger for humans and the environment. The controller based on bio-muscle models has shown great performance in coordinating the redundant internal forces of TDMS. Therefore, adaptive controllers with disturbance observers are designed to improve the immunity of the system and thus directly regulate the internal forces between the bio-muscle models.

The aim of this paper is to present and evaluate a methodology for automatically constructing and applying the physiologically‐realistic boundary/loading conditions for use in the structural finite element analysis of the femur during various exertion tasks (e.g. gait/walking).

To obtain physiologically‐realistic boundary/loading conditions needed in the femur structural finite element analysis, a whole‐body musculoskeletal inverse dynamics analysis is carried out and the resulting muscle forces and joint reaction forces/moments extracted.

The finite element results obtained are compared with their counterparts available in literature and it is found that the overall agreement is acceptable while the highly automated procedure for the finite element model generation developed in the present work made the analysis fairly easy and computationally highly efficient. Potential sources of errors in the current procedure have been identified and the measures for their mitigation recommended.

The present approach enables a more accurate determination of the physiological loads experienced by the orthopedic implants which can be of great value to implant designers and orthopedic surgeons.

The purpose of this paper is to compare fracture‐fixation and bone‐healing promotion efficacies of an intramedullary (IM) nail‐type and an external osteosynthesis plate‐type femoral trochanteric‐fracture implants using the results of a combined multi‐body dynamics and finite element analyses. For both implants, fracture fixation was obtained using a dynamic hip blade which is anchored to the femur head on one end and is connected to the IM rod/plate on the other. The analysis was carried out for two pre‐fracture conditions of the femur: healthy and osteoporotic.

The musculoskeletal dynamics portion of the analysis was used to obtain realistic physiological loading conditions (i.e. muscle forces and joint reaction forces and moments) associated with four typical everyday activities of a patient, namely, walking, lunging, cycling and egress (i.e. exiting a passenger vehicle). The subsequent structural finite element analysis of the fractured femur/implant assembly was employed to quantify fracture‐fixation efficacy (as measured by the extents of lateral (found to be minor), flexural and torsional displacements of the two femur fragments) and the bone‐healing promotion efficacy (as quantified by the fraction of the fractured surface area which experienced desirable contact pressures).

The results obtained show that, in general, the IM‐rod type of implant out‐performs the osteosynthesis plate type of implant over a large range of scenarios involving relative importance of the bone‐healing promotion and fracture‐fixation efficacies, health condition of the femur and the activity level of the patient. More specifically, the more active the patient and the larger extent of osteoporosis in the femur, the more justifiable is the use of the IM‐rod type of implant.

The present approach enables assessment of the fracture‐fixation performance of orthopedic implants under physiologically realistic loading conditions.

The Epidemiologic Transition can help us understand a fundamental puzzle about aging. The puzzle stems from two seemingly contradictory facts. The first fact is that death rates from noninfectious degenerative maladies – the so-called diseases of aging – increase as people age. It seems to be at odds with the historical fact that for nearly a century in which people were aging more than ever before, the aggregate rates of such diseases have been decreasing. In what sense can both be true? Crucial to resolving the puzzle are the age-profiles of such diseases in cohorts that grew up in the different regimes of the Transition. For each cohort, noninfectious diseases had increased with age, resulting in an upward-sloping age profile, which affirms the first fact. As the regimes were transitioning from the Malthusian to the modern one, however, the profiles of successive cohorts had been shifting downward: death rates from noninfectious diseases were shrinking at each age, signifying the newer cohorts’ greater aging potentials. The shifting profiles had been renewing the cohort mix of the population, shaping the century-long descent of such diseases in aggregate, giving rise to the historical fact. The profiles had shifted early in the cohorts’ adult years, associating closely with the newer epidemiologic conditions in childhood. Those conditions appear to be a circumstance under which aging potentials of cohorts could be misgauged, including in one troubling episode in the first half of the nineteenth century when the potentials had reversed.

The study aimed to evaluate the effectiveness of the Healthy e-Elderly People Intervention (HEPI) mobile application in reducing the physical health effects caused by smartphone usage.

This randomized controlled trial involved elderly volunteers residing in different regions of Thailand and using smartphones. The samples included 33 participants in each control and intervention group. The intervention group received the HEPI application with reminder messages, while the control group received the HEPI application without reminder messages. Assessments were conducted at baseline, follow-up 1 (four weeks after the last reminder messages) and follow-up 2 (12 weeks after the last reminder messages). Data analyses (i.e descriptive statistics, independent sample t-tests and repeated-measures analysis of variance) were used to obtain the overall mean change difference between the intervention and control groups at different time points (per-protocol analysis). The priorities of physical health risk were assessed using Health Risk Matrix.

The HEPI mobile application significantly improved knowledge, attitudes and practice scores in both the HEPI with and without reminder messages. The mean physical health risk score in both control and intervention groups was radically decreased from baseline to follow-up 1; lower physical health scores suggested lower health risk.

Increased duration of smartphone usage by elderly individuals in Thailand may result in a risk of developing several serious health conditions. The HEPI application with reminder messages could be used as a tool to benefit smartphone users and would further benefit from a booster after four weeks of intervention.

Aging population is on the rise around the world. Strategies to improve quality of life in this population are being implemented. Exercise is one of those strategies that has been proven to be effective as it produces many health benefits. The purpose of this paper is to determine the effects of Khon exercise on functional fitness in older persons.

In total, 44 older people aged 60–65 years were recruited through a senior club in an urban area. They were divided into two groups: the Khon exercise group (performed exercise for 12 weeks, 60 min/day, 3 times/week) and the control group (engaged in routine physical activity). The Senior Fitness Test, which consisted of chair stand, arm curl, 2-min step, chair sit and reach, back scratch, 8-ft up and go, and body mass index, was performed before and at 12 weeks after the exercise.

After 12 weeks of training, significant differences in chair stand, 2-min step, chair sit and reach, and 8-ft up and go tests were noted between the exercise and control groups.

These findings showed that Khon exercise has positive effects on lower body strength and flexibility, aerobic endurance and balance. Hence, it is recommended for health promotion among older persons.

Human-like musculoskeletal robots can fulfill flexible movement and manipulation with the help of multi joints and actuators. However, in general, sophisticated structures, accurate sensors and well-designed control are all necessary for a musculoskeletal robot to achieve high-precision movement. How to realize the reliable and accurate movement of the robot under the condition of limited sensing and control accuracy is still a bottleneck problem. This paper aims to improve the movement performance of musculoskeletal system by bio-inspired method.

Inspired by two kinds of natural constraints, the convergent force field found in neuroscience and attractive region in the environment found in information science, the authors proposed a structure transforming optimization algorithm for constructing constraint force field in musculoskeletal robots. Due to the characteristics of rigid-flexible coupling and variable structures, a constraint force field can be constructed in the task space of the musculoskeletal robot by optimizing the arrangement of muscles.

With the help of the constraint force field, the robot can complete precise and robust movement with constant control signals, which brings in the possibility to reduce the requirement of sensing feedback during the motion control of the robot. Experiments are conducted on a musculoskeletal model to evaluate the performance of the proposed method in movement accuracy, noise robustness and structure sensitivity.

A novel concept, constraint force field, is proposed to realize high-precision movements of musculoskeletal robots. It provides a new theoretical basis for improving the performance of robotic manipulation such as assembly and grasping under the condition that the accuracy of control and sensory are limited.