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The design of a new robotic orthosis to fully assist various overhead operations in the shipbuilding industry is proposed, and a dynamics simulation and an experimental study are conducted to validate the performance of impedance control of the new orthosis. There are considerable payloads from cables and reaction forces from injection parts during the blasting cleaning and painting in the shipbuilding process, and these can lead to work-related musculoskeletal disorders in the shoulder and elbow joints. Thus, in this research, the entire robotic orthosis designed for the dynamics simulation consists of joints with a total of 6 degrees of freedom (DOF): a 2-DOF shoulder, a 1-DOF elbow, and a 3-DOF wrist. The equations of motion of the designed robotic orthosis have been obtained on the basis of a relative-coordinate formulation. The contact force between the robotic orthosis and the human hand, gravitational force, and the control forces were considered as external forces. The results of the dynamics simulation are significant and show that the transient motions of robotic orthosis can be well controlled by using an impedance control scheme, while the compliance control is able to control only the steady-state motions. The control of transient motions is important because any unexpected impact forces or undesired dynamic behaviours in human–robot interactions may negatively affect both the worker's physical conditions and the quality of the work. Thus, in this research, we validate the suitability of the impedance control scheme in the described applications. Moreover, for simplicity of the experimental study and for considering the minimally required DOF in painting and blasting, only 3-DOF motions were considered in the dynamics simulation in this research. Finally, the obtained experimental results fully support the idea that the impedance control scheme is appropriate to control the robotic orthosis for overhead operations requiring a high degree of accuracy. [ABSTRACT FROM PUBLISHER]

Background and Objectives: While body weight support (BWS) intonation is vital during conventional gait training of neurologically challenged subjects, it is important to evaluate its effect during robot assisted gait training. In the present research we have studied the effect of BWS intonation on muscle activities during robotic gait training using dynamic simulations. Methods: Two dimensional (2-D) musculoskeletal model of human gait was developed conjointly with another 2-D model of a robotic orthosis capable of actuating hip, knee and ankle joints simultaneously. The musculoskeletal model consists of eight major muscle groups namely; soleus (SOL), gastrocnemius (GAS), tibialis anterior (TA), hamstrings (HAM), vasti (VAS), gluteus maximus (GLU), uniarticular hip flexors (iliopsoas, IP), and Rectus Femoris (RF). BWS was provided at levels of 0, 20, 40 and 60% during the simulations. In order to obtain a feasible set of muscle activities during subsequent gait cycles, an inverse dynamics algorithm along with a quadratic minimization algorithm was implemented. Results: The dynamic parameters of the robot assisted human gait such as joint angle trajectories, ground contact force (GCF), human limb joint torques and robot induced torques at different levels of BWS were derived. The patterns of muscle activities at variable BWS were derived and analysed. For most part of the gait cycle (GC) the muscle activation patterns are quite similar for all levels of BWS as is apparent from the mean of muscle activities for the complete GC. Conclusions: Effect of BWS variation during robot assisted gait on muscle activities was studied by developing dynamic simulation. It is expected that the proposed dynamic simulation approach will provide important inferences and information about the muscle function variations consequent upon a change in BWS during robot assisted gait. This information shall be quite important while investigating the influence of BWS intonation on neuromuscular parameters of interest during robotic gait training. [ABSTRACT FROM AUTHOR]

Background: Recent advances in technology have made possible the delivery of health services to patients remotely, and telerehabilitation for stroke survivors has emerged as a promising intervention. This systematic review assessed the clinical effectiveness of telerehabilitation (TR) programmes on quality-of-life (QoL) of stroke survivor compared to standard care. Methods: MEDLINE, CINAHL, AMED, Web of Science, and Scopus databases were searched from inception to 10 June 2022. Studies were considered eligible for inclusion if they fulfilled the following criteria: assessed the efficacy of different telerehabilitation models in poststroke patients, employed randomised controlled trial, and non-randomised design, stroke survivor adults age ≥ 18 years, health-related quality of life outcome, and full text available. Data were extracted by two independent researchers. Risk of bias was assessed by the Cochrane Handbook for Systematic Reviews of Interventions. A meta-analysis was performed among trials presenting with similar clinical characteristics. Results: A total of 11 eligible studies that met the inclusion criteria were included in the review. These studies were conducted in Brazil (n = 1), Italy (n = 2), the Netherlands (n = 1), South Korea (n = 1), Taiwan (n = 1), United Kingdom (n = 1) and United States (n = 4) between 2004 and 2020. Except for blinding of participants to study group allocation, all the studies were (>50%) at low risk of bias to considering adequate sequence generation, allocation concealment, blinding of trial personnel or outcome assessors, evaluation of incomplete outcome data, and lack of selective reporting. The meta-analysis (n = 5) included 306 individuals with duration of follow-up ranged between 4 and 12 weeks. We found that there were no statistically significant difference (SMD = 0.089, confidence interval (CI) 95% = −0.184 to 0.362, p = 0.522) for Stroke Impact Scale between the interventions and the control. Conclusion: The review provides evidence for the effectiveness of TR interventions to improve the QoL of stroke survivors in a short term. Further research studies are required to examine the effectiveness of TR interventions for stroke survivors in a long-term follow-up. [ABSTRACT FROM AUTHOR]

Introduction: Robot-assisted neuro-rehabilitation is gaining acceptability among the physical therapy community. The ankle is one of the most complicated anatomical joints in the human body and neurologic injuries such as stroke often result in ankle and foot disabilities. Areas covered: Robotic solutions for the ankle joint physical therapy have extensively been researched. Significant research has been conducted on the mechanism design, actuation as well as control of these ankle rehabilitation robots. Also, the experimental evaluations of these robots have been conducted with healthy and neurologically impaired subjects. This paper presents a comprehensive review of the recent developments in the field of robot-assisted ankle rehabilitation. Mechanism design, actuation, and various types of control strategies are discussed. Also, the experimental evaluations of these ankle rehabilitation robots are discussed in the context of the evaluation of robotic hardware with healthy subjects as well as motor function outcomes with neurologically impaired subjects. Expert opinion: Significant progress in the mechanism design, control, and experimental evaluations of the ankle rehabilitation robots have been reported. However, more sensing and reference trajectory generation methods need to be developed as well as more objective quantitive evaluations that need to be conducted for establishing the clinical significance of these robots. [ABSTRACT FROM AUTHOR]

Task-specific rehabilitation is a key indicator for successful rehabilitation to improve the upper limb performance after stroke. Assistive robotic and non-robotic devices are emerging to provide rehabilitation therapy; however, the effectiveness of task-specific training programs using assistive training devices compared with task-specific usual care training has not been summarized yet. Therefore, the effectiveness of task-specific training using assistive arm devices (TST-AAD) compared with task-specific usual care (TSUC) on the upper limb performance of patients with a stroke was investigated. To assess task specificity, a set of criteria was proposed: participation, program, relevant, repeated, randomized, reconstruction and reinforced. Out of 855 articles, 17 fulfilled the selection criteria. A meta-analysis was performed on the Fugl-Meyer Assessment scores in the subacute and chronic stages after stroke and during follow-up. Both TST-AAD and TSUC improved the upper limb performance after stroke. In the sub-acute phase after stroke, TST-AAD was more effective than TSUC in reducing the upper limb impairment, although findings were based on only three studies. In the chronic phase, TST-AAD and TSUC showed similar effectiveness. No differences between the two types of training were found at the follow-up measurements. Future studies should describe training, device usage and criteria of task specificity in a standardized way to ease comparison. Arm or hand function is often undertreated in stroke patients, assistive training devices may be able to improve the upper limb performance. Task-specific training using assistive devices is effective in improving the upper limb performance after stroke. Task-specific training using assistive devices seems to be more effective in reducing impairment compared with task specific usual care in the subacute phase after stroke, but they are equally effective in the chronic phase of stroke. [ABSTRACT FROM AUTHOR]

Aiming at the position and pose control requirement of the ankle rehabilitation robot, two schemes of 3-PRS (Prismatic-Revolute-Spherical) parallel ankle rehabilitation robots are proposed, and the analysis and simulation of the control strategy are carried out. Two schemes of 3-PRS ankle rehabilitation robots are statically analysed by the finite element method. Through the stress comparison of the two schemes, the stable one is determined. Three control strategies including the traditional PID control, PID control based on the genetic algorithm and adaptive fuzzy PID control are proposed. A multidisciplinary co-simulation platform is established by the combination of ADAMS, SOLIDWORKS and MATLAB, and the three control strategies are verified. The best control strategy for the rehabilitation robots is determined by comparing control effects. This study lays a solid foundation for research on the control of the rehabilitation robots. [ABSTRACT FROM AUTHOR]

The objective of this work is to design a neuro-fuzzy compensated PID control for passive gait rehabilitation using a lower extremity exoskeleton system. A prototype of 6-DOFs exoskeleton device is developed to assist the children of age 8–10 years old. A dummy having a well-matched body attributes to a healthy child (10 years) is utilized in this work to carry out the experimental runs. Kinect-LabVIEW setup is employed to compute the desired joint angles in the sagittal plane for a healthy gait trajectory. The Euler–Lagrange method is utilized to formulate the dynamic analysis of the exoskeleton system. As the performance of existing control strategies for gait rehabilitation devices is still debatable; therefore, a robust neuro-fuzzy compensated PID control strategy is designed in this work. The asymptotic stability of the proposed control scheme is proved mathematically by Lyapunov theorem. Thereafter, the proposed control strategy is implemented on the exoskeleton-dummy setup in real-time and compared with the classical PID control strategy. From experimental runs, the root mean square error (RMSE) for proposed control scheme is found to be less by 40% nearly while tracking the desired gait trajectory. The robustness of the proposed controller is also validated by varying lower limb masses of dummy and by providing an external disturbance. It is observed that proposed controller is more robust to deal with the input disturbance as compared to parametric uncertainty. Finally, the low values of settling time in both the directions ensures the fast convergence of proposed controller. [ABSTRACT FROM AUTHOR]

To identify the short-term effects of robotic-assisted gait training (RAGT) on walking distance, gait speed and functionality of cerebral palsy (CP) patients, and to verify if the effects of RAGT are maintained in the long term. A systematic literature review was performed in PubMed, PEDro, CINAHL, and LILACS databases. Studies were included considering: (1) population (CP individuals); (2) study design (experimental studies); (3) type of intervention (RAGT); (4) outcome (gait parameters and function); and (5) period (short and long term). This systematic review included seven articles in meta-analysis. Only walking distance, thru six minutes walking test, increased statistically after RAGT. However, RAGT demonstrated large clinical effects differences (minimal clinically important difference – MCID) in gait speed and Gross Motor Function Measure score (dimensions D and E), for CP population. After RAGT intervention, differences in short term (comparison 1) were maintained in long term (comparison 2) for all outcomes. Gait speed results were not significant. Evidence from the present study demonstrated that RAGT can be an important intervention to improve gait parameters and functionality, in children with CP, that are maintained over long-term. Robotic-assisted gait training (RAGT) is a beneficial treatment for children with cerebral palsy (CP). RAGT improvements in walking distance are maintained over the long-term in children with CP. RAGT demonstrated large clinical effect differences in gait speed and functionality in CP population. [ABSTRACT FROM AUTHOR]

The objective of this study was to examine the feasibility of an 8-week walking training programme using a novel assistive gait training device in individuals with chronic spinal cord injury (SCI). This study was a pilot, single group, pretest-posttest study design. Participants received walking training, 3 sessions a week for 8 weeks. Participants were trained on a treadmill using a novel assistive gait training device. Feasibility data about recruitment, retention, compliance, and participants' performance, and participants' perception were collected throughout the study period. 11 participants with chronic SCI (8 males, 3 females, age: 38 ± 10 years old, injury levels T3-L1; injury onset 8 ± 10 years) completed the study. The recruitment rate of 27.2% reached in this study was acceptable. Throughout the period of training, all participants were able to progress in their walking performance with respect to treadmill speed, walking distance, duration of training, and percentage of body weight support. The overall compliance rate of participants with training sessions was 96.2 ± 6.5%. From responses to the end intervention questionnaire, the majority of participants showed positive perception to the walking training programme as well as the assistive gait training. The 8 weeks of walking training was feasible in individuals with chronic SCI. The assistive gait training device was feasible and safe to use in individuals with paraplegia. Clinical Trials Registration Number: NCT03940274 The use of a novel assistive gait training device using a pulley system with a pulling cable walking training is feasible. The novel assistive gait training device will reduce workload by allowing physical therapists to work on an ergonomic position while providing the necessary stepping assistance for the patient's legs/feet during walking on a treadmill. The novel assistive gait training device is developed to provide a low-cost assistive device to be used in walking rehabilitation for people with spinal cord injury. [ABSTRACT FROM AUTHOR]

People with mobility impairments have reported that improving their walking is one of the most important goals of their rehabilitation. Novel robotic technologies using powered exoskeletons for the lower limb could potentially offer efficient and less labour-intensive approaches to rehabilitation with shorter recovery times. To gather users' and carers' perspectives of assistive device use to provide information to design personalised and safe mobility rehabilitation technology. Semi-structured interviews were carried out with people with experience of mobility impairments. Iterative data collection was used to gather information about the social phenomena surrounding patient interaction and requirements for assistive devices for mobility impairments. Cycles of continuous data collection and thematic analysis using a theoretical, semantic approach was used to develop key themes within the data. We interviewed eight people: six people with mobility impairments and two carers. We identified five main themes: relationship with assistive technology, requirements for assistive technology, function and goal setting, personal factors to assistive device use and psychosocial factors to assistive device use. There was variability in the importance placed on each theme, particularly in the trade-off between the function and comfort of assistive technology. Patients emphasised the need for assistive technology to be personalised; they reported the ability to stand, control spasticity and involvement in community roles as key goals of their rehabilitation. These results highlight the variation in requirements for assistive technology between people with different mobility impairments; individuals' experiences are unique and future prototypes need to account for different levels of impairments and personal goals. These findings will also inform the user evaluation stage of assistive device testing. The acceptability of assistive devices is dependent upon a number of factors, including personalisation, comfort and function. Future pilot studies should gather qualitative data to determine the acceptability of actual device use. [ABSTRACT FROM AUTHOR]

Stroke is the leading cause of long-term disability in developed countries. Due to population aging, the number of people requiring rehabilitation after stroke is going to rise in the coming decades. Robot-mediated neurorehabilitation has the potential to improve clinical outcomes of rehabilitation treatments. A statistical analysis of the literature aims to focus on the main trend of this topic. A bibliometric survey on post-stroke robotic rehabilitation was performed through a database collection of scientific publications in the field of rehabilitation robotics. By covering the last 20 years, 17,429 sources were collected. Relevant patterns and statistics concerning the main research areas were analyzed. Leading journals and conferences which publish and disseminate knowledge in the field were identified. A detailed nomenclature study was carried out. The time trends of the research field were captured. Opinions and predictions of future trends that are expected to shape the near future of the field were discussed. Data analysis reveals the continuous expansion of the research field over the last two decades, which is expected to rise considerably in near future. More attention will be paid to the lower limbs rehabilitation and disease/design specific applications in early-stage patients. [ABSTRACT FROM AUTHOR]

Parallel robots are preferred over serial robots owing to their enhanced accuracy and rigidity which comes from their higher stiffness. However, there are applications both in industry and in healthcare where higher accuracy is required alongside high compliance (reduced stiffness). Accuracy and compliance being conflicting to each other are difficult to achieve simultaneously. To address this issue, an intrinsically compliant 6-dof parallel robot is proposed in this work. Kinematic and analytical modeling is performed for its conceptual design to obtain the Jacobian matrix and thereby map the joint and Cartesian spaces. Robot's structure design is analyzed, and the wrench analysis is also carried out to estimate the link forces and stiffness. It is shown that by small changes in the proposed robot design; its compliance can be altered making it suitable for a range of applications. It is also shown mathematically that the robot design can be optimized to maintain higher accuracy together with higher compliance. To carry out design optimization, three important performance criteria, namely; global condition number (for higher accuracies), norm of link forces (to reduce actuator power requirement) and robot compliance (for response to an external wrench) are mathematically formulated. Later, a multi-criteria optimization is performed using an evolutionary algorithm to simultaneously optimize these performance criteria. From the final robot design selected, it is evident that a higher robot compliance with optimal condition number and link forces can be achieved. [ABSTRACT FROM AUTHOR]

We provide an overview of some biomedical technologies able to relieve everyday impairments in neurological patients. Two literature searches from 2009 to 2020 were conducted using PubMed, Embase, Cinahl and Scopus. The studies meeting the criteria for eligibility constituted 224 of the 6257 identified studies. The first literature search resulted in the identification of 53 different neurological impairments. The following impairments were selected as the most general: six motor (walking/gait abnormality, paralysis/paresis, hypertonia, dystonia, tremor and ataxia), three cognitive (memory, attention/concentration and executive dysfunction), two sensory (visual and hearing impairments) and three uncategorized impairments (communication impairments, sleep abnormalities and seizures/epilepsies). The second literature search resulted in the identification of 22 biomedical technologies able to compensate or rehabilitate the neurological impairments. This review identified some of the common neurological impairments across diseases and showed that technology can be beneficial for neurological patients by helping them with everyday living. The review also found that different aspects such as personal aspects of the intended users (e.g., impairments) and physical and environmental context of the task play an essential role in the usefulness of the technology. Neurological diseases are globally the leading cause of disability, whereby there is a great need for rehabilitation of neurological impairments. Assistive technology can compensate for permanent impairments or be used in rehabilitation as an alternative to usual therapy or an adjunct to increase overall therapy time. This study provides an overview of existing assistive technology and how patients with neurological impairments can benefit from technology. [ABSTRACT FROM AUTHOR]

Utilizing exoskeleton devices to help elderly or empower workers is a growing field of research in robotics. The structure of an exoskeleton can vary depending on user's physical dimensions, joints or muscles targeted for assistance, and maximum achievable actuator torque. In this research, a Human-Model-In-the-Loop (HMIL) constrained optimization technique is proposed to design the RoboWalk lower-limb exoskeleton. RoboWalk is an under-actuated non-anthropomorphic assistive robot, that besides applying the desired assistive force, exerts an undesirable disturbing force leading to the user's fall. The HMIL method uses the augmented human-robot 2D model to take RoboWalk and human body's joint torques into account during optimization. The superiority of HMIL method is proven by comparing the results with other strategies in the literature. Obtained results reveal elimination of the disturbing forces, 2 N.m. reduction in average human knee-joint torque, and significant decrease in the actuator required torque. [ABSTRACT FROM AUTHOR]

Evolution of gait rehabilitation robotic devices for stroke survivors has aimed at providing transparency to user's efforts and implementing 'assist-as-needed' paradigm. Alteration of muscle activity and synergies recruitment has been noticed in trials involving healthy subjects but no analytic tool has been proposed to understand root causes. In this paper, a simplified neuro-mechanical model is introduced for simulating lower limbs' muscle activity during unrestrained and device-constrained gait, taking into consideration exoskeleton-plus-treadmill and end-effector categories. Muscle control is based on the key hypothesis that optimality criterion pursues co-occurrence between effort minimisation and modularity during regular gait. Results highlight that modelised motion constraints on lower body raise additional redundancies which alter muscle activity and increase intervention external to unrestrained gait synergies. Accordingly, the developed simulations help to identify the inherent limitations of current technology: further degree of freedom addition to exoskeleton-plus-treadmill device could be useful but impractical, while end-effector devices would benefit significantly from an improved interaction management. [ABSTRACT FROM AUTHOR]

Transcranial direct current stimulation (TDCS) and robot-assisted therapy (RAT) proved to be promising interventions in post-stroke rehabilitation. However, the effects of combining the two treatments are not significantly clear. To determine the effects of combined therapy using transcranial direct current stimulation (tDCS) with robot-assisted therapy (RAT) in the impairment of the upper limb in stroke rehabilitation. The Cochrane Library, MEDLINE, Embase, Google Scholar, and Trial Registries were systematically searched for randomised controlled trials in May 2020. As the outcome, the Fugl-Meyer Assessment score (FMS) was used. A pairwise and a network meta-analysis were performed. 5 RCTs with RAT versus RAT + tDCS groups and 21 RCTs with RAT versus the control group with 892 people were analysed. Of these studies, 10 RCTs evaluated acute-subacute (<8 weeks) people, while 16 chronic people. By analysing the FMS with a pair-wise meta-analysis, we demonstrate significant improvements only in the RAT alone compared to the control (acute-subacute, SMD:4.09 (1.31, 6.87) and chronic, SMD:2.22 (0.99, 3.45)). Instead, performing a network meta-analysis, through an analysis of the surface under the cumulative ranking curve (SUCRA) we report a ranking of the effectiveness of the interventions. We assess SUCRA in acute-subacute stroke: Control:0.23, RAT + tDCS:0.31, RAT:0.96 and in chronic stroke: Control:0.06, RAT + tDCS:0.62, RAT:0.82. RAT is, respectively, 96% and 82% likely to be the best-ranked treatment. Despite the limitations, this network meta-analysis appears to demonstrate through the rank of interventions that adding tDCS to RAT is not useful in upper-limb stroke rehabilitation. [ABSTRACT FROM AUTHOR]

Emerging technologies such as robotics and virtual reality (VR) are being trialled and implemented into physiotherapy practice. As emerging technologies compete for market share, trials on emerging technologies are at risk of spin. For consumers to make informed decisions about whether to use a new technology, trials should accurately portray the results. If spin is present, outcomes may not be comparable to the results reported when interventions are implemented clinically. To determine the amount and type of spin in abstracts of physiotherapy clinical trials that use robotic or VR interventions. A secondary objective is to determine the agreement between raters, both experienced and inexperienced, using an existing 7-item checklist with updated item definitions. We will perform two meta-research reviews on a random set of 100 robotics (study 1) and 100 VR (study 2) trials, from any year, indexed in the PEDro database. Using the updated spin checklist, the abstract of each trial will be assessed in corroboration with full-text. The total spin score and proportion of studies with spin for each item will be reported. Agreement between experienced and inexperienced raters will be determined using kappa statistics. Rater confidence in rating each item will be collected. We will identify if spin is present in robotics and VR literature and evaluate if the spin checklist can be confidently and consistently used by raters. We hope this research will facilitate best-practice reporting of research findings so emerging technologies will be implemented with realistic expectation of clinical outcome. [ABSTRACT FROM AUTHOR]

Purpose: The Lokomat is a commercially available robotic gait trainer, applied for gait rehabilitation in post-stroke hemiparetic patients. Selective and well-dosed clinical use of the Lokomat training parameters, i.e. guidance, speed and bodyweight support, requires a good understanding of how these parameters affect the neuromuscular control of post-stroke hemiparetic gait. Materials and methods: Ten stroke patients (unilateral paresis, 7 females, 64.5 ± 6.4 years, >3months post-stroke, FAC scores 2–4)) walked in the Lokomat under varying parameter settings: 50% or 100% guidance, 0.28 or 0.56m/s, 0% or 50% bodyweight support. Electromyography was recorded bilaterally from Gluteus Medius, Biceps Femoris, Vastus Lateralis, Medial Gastrocnemius, and Tibialis Anterior. Pressure sensors placed under the feet were used to determine the level of temporal gait symmetry. Results: Varying guidance and bodyweight support had little effect on muscle activity, but increasing treadmill speed led to increased activity in both the affected (Biceps Femoris, Medial Gastrocnemius, Tibialis Anterior) and unaffected leg (all muscles). The level of temporal symmetry was unaffected by the parameter settings. Conclusions: The Lokomat training parameters are generally ineffective in shaping short term muscle activity and step symmetry patients with hemiparetic stroke, as speed is the only parameter that significantly affects muscular amplitude. Trial Registration: d.n.a. The Lokomat is a commercially available gait trainer that can be used for gait rehabilitation in post-stroke hemiparetic patients. This study shows that muscle amplitude is generally low during Lokomat guided walking, and that treadmill Speed is the main training parameter to influence muscular output in stroke patients during Lokomat walking. Varying Guidance and Bodyweight Support within a clinical relevant range barely affected muscle activity, and temporal step symmetry was unaffected by variation in any of the training parameters. Based on the findings it is advised to increase speed as early as possible during Lokomat therapy, or use other means (e.g. feedback or instructions) to stimulate active involvement of patients during training. [ABSTRACT FROM AUTHOR]

Brain–computer interfaces (BCI) decode user's intentions to control external devices. However, performance variations across individuals have limited their use to laboratory environments. Handedness could contribute to these variations, especially when motor imagery (MI) tasks are used for BCI control. To further understand how handedness affects BCI control, performance differences between two monozygotic twins were analysed during offline movement and MI tasks, and while twins controlled a BCI using right-hand MI. Quantitative electroencephalography (qEEG), brain structures' volumes, and neuropsychological tests were assessed to evaluate physiological, anatomical and psychological relationships with BCI performance. Results showed that both twins had good motor imagery and attention abilities, similar volumes on most subcortical brain structures, more pronounced event-related desynchronization elicited by the twin performing non-dominant MI, and that this twin also obtained significant higher performances with the BCI. Linear regression analysis implied a strong association between twins' BCI performance, and more pronounced cortical activations in the contralateral hemisphere relative to hand MI. Therefore, it is possible that BCI performance was related with the ability of each twin to elicit cortical activations during hand MI, and less associated with subcortical brain structures' volumes and neuropsychological tests. [ABSTRACT FROM AUTHOR]

This paper aims to address the trajectory control of a lower limb rehabilitation robot which works under passive mode. Udwadia–Kalaba approach is a novel and concise method to address the control of constrained systems with holonomic and nonholonomic constraints. According to Udwadia–Kalaba approach, the fundamental equation of lower limb rehabilitation robot considering the resistance of human muscles is first obtained, then a closed-form expression of the joint control torques is obtained. In practice, it is quite difficult to meet the control target due to various uncertainties such as the initial condition deviation from the constraints, the uncertainty of model, and the external disturbance. To deal with this condition, an adaptive control on the basis of Udwadia–Kalaba approach is presented. The uniform boundedness and the uniform ultimate boundedness of the proposed control are verified by the Lyapunov method. Experiments and simulations are performed to show the simplicity, efficiency and accuracy of the proposed control. Specifically, the tracking trajectory of the robot is designed based on the data collected from the experiments. The simulation results show that the proposed control can be used in the lower limb rehabilitation robot. [ABSTRACT FROM AUTHOR]

Background: Traumatic brain injury (TBI) is a clinical condition characterized by damage due to a mechanical physical event, which has a devastating impact on both the patient and his/her family. The purpose of this study is to evaluate the effects of robotic neurorehabilitation using Lokomat with virtual reality (VR) on attention processes and executive functions in patients with TBI. Materials and Methods: This is a retrospective case-control study. Fifty-six TBI patients have been included in the analysis, using an electronic recovery data system. The enrolled patients were divided into two groups: the experimental group (LPG) underwent rehabilitation training with Lokomat Pro, equipped with a VR screen, whereas the control group (LNG) performed rehabilitation training using Lokomat Nanos, without VR. The two groups matched for age, sex, education, brain lesions, interval from TBI. The rehabilitation protocol consisted of a total of 40 training sessions. Results: LPG and LNG had a significant improvement in mood and in the perception of physical well-being. However, only the LPG had a significant improvement in global cognitive, executive and attention functions. Furthermore, LPG presented a significant enhancement of the quality of life, with regard to the perception of the mental and physical state. Conclusion: Our study supports the idea that Lokomat is a useful tool in the rehabilitation of patients with TBI; in particular, the integration of the VR device can implement the cognitive and behavioral functions of TBI patients, enhancing also their physical and mental well-being. [ABSTRACT FROM AUTHOR]

Purpose: To establish feasibility, acceptability, and preliminary efficacy of an adapted version of a commercially available, virtual-reality gaming system (the Personalised Stroke Therapy system) for upper-limb rehabilitation with community dwelling stroke-survivors. Method: Twelve stroke-survivors (nine females, mean age 58 years, [standard deviation 7.1], median stroke chronicity 42 months [interquartile range 34.7], Motricity index 14–25 for shoulder and elbow) were asked to complete nine, 40-min intervention sessions using two activities on the system over 3 weeks. Feasibility and acceptability were assessed through a semi-structured interview, recording of adverse effects, adherence, enjoyment (using an 11-point Likert scale), and perceived exertion (using the BORG scale). Assessments of impairment (Fugl–Meyer Assessment Upper extremity), activity (ABILHAND, Action Research Arm Test, Motor Activity Log-28), and participation (Subjective Index of Physical and Social Outcome) were completed at baseline, following intervention, and at 4-week follow-up. Data were analysed using Thematic Analysis of interview and intervention field-notes and Wilcoxon Signed Ranks. Side-by-side displays were used to integrate findings. Results: Participants received between 175 and 336 min of intervention. Thirteen non-serious adverse effects were reported by five participants. Participants reported a high level of enjoyment (8.1 and 6.8 out of 10) and rated exertion between 11.6 and 12.9 out of 20. Themes of improvements in impairments and increased spontaneous use in functional activities were identified and supported by improvements in all outcome measures between baseline and post-intervention (p < 0.05 for all measures). Conclusions: Integrated findings suggested that the system is feasible and acceptable for use with a group of community-dwelling stroke-survivors including those with moderately-severe disability. To ensure feasibility of use and maintenance of an appropriate level of challenge, gaming technologies for use in upper-limb stroke rehabilitation should be personalised, dependent on individual need. Through the use of hands-free systems and personalisation, stroke survivors with moderate and moderately-severe levels of upper-limb impairment following stroke are able to use gaming technologies as a means of delivering upper-limb rehabilitation. Future studies should address issues of acceptability, feasibility, and efficacy of personalised gaming technologies for delivery of upper-limb stroke rehabilitation in the home environment. Findings from this study can be used to develop future games and activities suitable for use in stroke rehabilitation. [ABSTRACT FROM AUTHOR]

Purpose: The assistive knee exoskeleton device is used for supporting the surrounding ligaments, tendons, and muscles of the injured knee joint. Various knee exoskeletons have been discussed; however, their shape synthesis is not reported. This study aims to present the shape synthesis of the assistive knee device. Moreover, four-bar linkage is used for the knee exoskeleton, in this study. Methods: Clinical biomechanical data are adapted from gait database for one gait cycle. Using the clinical gait data, position and static force analyses are performed to obtain a set of orientations and unknown forces. Simultaneously, CAD models are prepared, and the obtained forces are applied to the CAD models of the four-bar linkage knee exoskeleton. Consequently, the threshold is obtained for each component of the knee exoskeleton and the unwanted material below the threshold is removed. Results: A reduction of 45% in the peak actuating force is observed in comparison with the literature. Besides, a total reduction of 21% in the mass of four-bar knee exoskeleton is observed in contrast to the base models when shape synthesis is performed. Conclusions: An assistive knee exoskeleton is developed using the shape synthesis methodology in which four-bar linkage is used. New shapes of thigh and shank attachments are obtained. The developed knee exoskeleton can be used by persons with the injured knee for supporting the ligaments, tendons, and muscles. Besides, control technology can be implemented to make it useful for persons with monoplegia. Assistive knee exoskeleton devices proved to be an important tool for providing support to injured knee joints. Typically single axis joints are observed in the lower limb exoskeletons which can be replaced with linkage mechanisms to obtain the desired range of motion. In this study, four-bar linkages are used for the knee exoskeleton in which cranks and rockers are connected to the lateral and medial sides of the knee joint, for connecting shank and thigh attachments. Shape synthesis is performed on the components of four-bar exoskeleton through the evaluated reaction forces. The components are assembled to form an assistive knee exoskeleton which can be used by any person with injured knee joint. [ABSTRACT FROM AUTHOR]

Background: Upper limb (UL) hemiparesis is a common, disabling and persistent problem, and a major contributor to poor well-being and quality of life in persons after stroke. Conventional UL rehabilitation has had limited success. Novel combined interventions are being investigated in an effort to stimulate greater recovery. Objective: To identify and assess the efficacy of interventions combined with task-specific training aimed at UL motor recovery after stroke. Methods: A systematic search was undertaken in databases including MEDLINE, MEDLINE In-Process, EMBASE, AMED, CINAHL, OTseeker, and PEDro. Key inclusion criteria were: peer-reviewed articles published in English, adults after stroke, and an intervention combined with task-specific training targeted to improve motor function and/or impairment of the UL following stroke. Findings from included studies were synthesized qualitatively and meta-analyzed where there was sufficient homogeneity. Results: From 3494 citations identified, 120 papers (72 randomized controlled trials and 4 pseudo-randomized controlled trials) were included. Adjunctive interventions (21 categories) identified included electrical stimulation, transcranial magnetic stimulation, robotic devices, mental practice, action observation, trunk restraint, virtual reality, and resistance training. Of the interventions meta-analyzed, only peripheral nerve stimulation demonstrated small additional benefits over those of task-specific training alone for UL impairment, as measured by the Fugl-Meyer scale (MD 2.69, 95% CI 1.12, 4.26). Several individual studies found benefits for other interventions combined with task-specific training, but further investigations are needed to provide more comprehensive evidence of their efficacy. Conclusion: To date, there is little evidence that adding another intervention to TST confers additional benefits and therefore there is no evidence to guide rehabilitation professionals. Further research is required as heterogeneity of studies limited ability to conduct meta-analyses. [ABSTRACT FROM AUTHOR]

Bionic pectoral fins play an essential role in achieving the superior swimming ability of the bio-inspired undersea monitoring platform by producing desired movements and propulsion forces. This paper discusses the hydrodynamic modelling and experiments of a bionic pectoral fin inspired by the cownose ray. A simplified hydrodynamic model of the oscillatory bionic pectoral fin is built. A physical prototype of the bionic pectoral fin is developed based on the structure and movement parameters extracted from the cownose ray. Performances of the bionic pectoral fin in producing lift force and propulsion force are tested using a towing-tank experimental platform and compared with the results from corresponding simulations. Feasibility of the hydrodynamic simulation and the bionic design method are verified. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this review is to analyse the different existing technologies for gait rehabilitation, focusing mainly in robotic devices. Those robots help the patient to recover a lost function due to neurological gait disorders, accidents or after injury. Besides, they facilitate the identification of normal and abnormal features by registering muscle activity providing the doctor important data where he can observe the evolution of the patient. Method: A deep literature review was realized using selected keywords considering not only the most common medical and engineering databases, but also other available sources that provide information on commercial and scientific gait rehabilitation devices. The founded literature for this review corresponds to control techniques for gait rehabilitation robots, since the early seventies to the present year. Results: Different control strategies for gait analysis in rehabilitation devices have been developed and implemented such as position control, force and impedance control, haptic simulation, and control of EMG signals. These control techniques are used to analyze the force of the patient during therapy, compensating it with the force generated by the mechanism in the rehabilitation device. It is observed that the largest number of studies reported, focuses on the impedance control technique. Leading to include new control techniques and validate them using the necessary protocols with ill patients, obtaining reliable results that allows a progressive and active rehabilitation. Conclusions: With this exhaustive review, we can conclude that the degree of complexity of the rehabilitation device influences in short and long-term therapeutic results since the movements become more controlled. However, there is still a lot of work in the sense of motion control in order to perform trajectories that are more alike the natural movements of humans. There are many control techniques in other areas, which seek to improve the performance of the process. These techniques may possibly be applicable in gait rehabilitation devices, obtaining controllers that are more efficient and that adapts to different people and the necessities that entail every disease. Implications for Rehabilitation: Rehabilitation helps people to improve the activities of their daily life, allowing them to observe their progress in the functional abilities as the months pass by with intensive and repetitive therapies. There is a mobility issue when the patient needs to move to the hospital or to the laboratory, which is not always feasible. For overcoming it, patients use the equipment at home to perform their daily therapy. However, they need the sufficient knowledge about its operation, also about the therapeutic movements, the therapy duration and the movement speed. Besides, is necessary to place the equipment in a proper and lively environment that helps to forget or reduce pain while the patient moves his joints progressively. The purpose of robotic rehabilitation devices is to generate repetitive and progressive movements, according to the motor disability. There are training trajectories to follow, which motivate patients to generate active movements. The benefits of robotic rehabilitation depend on the ability of each patient to adapt to the speed and load variations generated by the device, improving and reinforcing motor functions in therapy, especially in patients with advanced disabilities in early rehabilitation. Multi-joint rehabilitation devices are more effective than single-joint rehabilitation devices because they involve a higher number of muscles in the therapy. The greater the number of degrees of freedom (DoF) of the device, it cushions its effect in the patient because the inertia is reduced and higher torques are generated. The assistive technological devices allows to explore different rehabilitation techniques that motivate the patient in therapy, increasing appropriately the energy and pressure in the blood which is reflected in gradually recovering his ability to walk. [ABSTRACT FROM AUTHOR]

Fractional order PID (FOPID) controllers have recently found an increasing application in different fields of control. Comparing to traditional PID algorithms, FOPID controllers provide more flexibility and better performances. The simple and non-model-based structure of FOPID controllers has boosted their usage in real-world applications. However, due to having two more control parameters than regular PID controllers and the non-linear structure of FOPID controllers, the tuning procedure of these controllers is still a challenge. The authors of the present paper have recently proposed a Taguchi-based gain tuning algorithm for tuning of control parameters of FOPID controller. The present paper is an experimental evaluation of the proposed method. A custom made SEA, FUM-LSEA, is used as the test bed in this study. Deriving a dynamic model of the FUM-LSEA, feed-forward terms are added to the controller to compensate for disturbances from motions of the output block. Optimal gains and orders of the controller are obtained through a set of experiments suggested by the Taguchi method. The Taguchi optimized controller is also compared to a Ziegler-Nichols tuned controller. The experimental results indicate 45% improvements in force tracking error. [ABSTRACT FROM AUTHOR]

Modeling the curving motion of humans in actual environment is rarely done because of the complexity and variability of the turning motion. In this study, various gait motions, including straight, round corner, and circular walks, were recorded and analyzed using factor analysis. As a result, we successfully extracted several factors that represent turning motions, such as long stride motion, turning motion led by the inner leg, and turning motion led by the outer leg. In particular, we found that the natural curving motion, which is a motion that results when turning around a round corner, is widely and continuously distributed on the factor space. Although several typical stepping strategies were reported by related studies, we found that the stepping motion changes between straight and turning gaits in the factor space during natural curving motions. Thus, the classification of curving motion into several typical distinct stepping patterns is probably insufficient to understand the natural curving motion. Furthermore, natural curving motions that comprise circular curving motions that were believed to represent typical curving motions was not validated. On the other hand, this result also suggests the possibility of generating curving motions for a physical assistant robot by combining straight gait and circler curving motion. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to evaluate the efficacy of a robotic-assisted gait training (RAGT), together with a conventional exercise program (CEP), to improve PD ambulation, as compared to standard gait training. Methods: Thirty-eight patients with mild PD stage (H&Y 2-2.5) were randomly assigned to an experimental group (EG) or a control group. The 19 patients in EG received 30 min RAGT (using Lokomat device), whereas the 19 controls received a conventional gait training; both groups received 30 min of CEP. Participants were evaluated before (T0), immediately after (T1), and 12 weeks after the end of treatment (T2), by using 10-MWT, Tinetti Test and the motor score of the UPDRS-III. Results: We found that Tinetti Walking (TW) (X²(3) = 31.75; p < 0.001), Tinetti Balance (X&#178(3) = 74.07; p < 0.001), UPDRS-III (X&#178(3) = 6.87; p < 0.001) and GDS (X&#178(3) = 28.83; p < 0.001) scores were affected by the type of the rehabilitative treatment. At T2, we found a significant difference between the two groups for TW (t D 2.62; p < 0.02, d = 0.85). Concerning all the study outcomes, a significant improvement was observed from T0 to T1 in both groups. However, the functional motor gain at T2 was maintained only in the EG. Conclusions: RAGT may significantly improve walking ability, motor function and for a maximum period of three months. Thus, our findings support the importance of a RAGT as a valid rehabilitative tool for PD. [ABSTRACT FROM AUTHOR]

The development of rehabilitation has traditionally focused on measurements of motor disorders and measurements of the improvements produced during the therapeutic process; however, physical rehabilitation sciences have not focused on understanding the philosophical and scientific principles in clinical intervention and how they are interrelated. The main aim of this paper is to explain the foundation stones of the disciplines of physical therapy, occupational therapy, and speech/language therapy in recovery from motor disorder. To reach our goals, the mechanistic view and how it is integrated into physical rehabilitation will first be explained. Next, a classification into mechanistic therapy based on an old version (automaton model) and a technological version (cyborg model) will be shown. Then, it will be shown how physical rehabilitation sciences found a new perspective in motor recovery, which is based on functionalism, during the cognitive revolution in the 1960s. Through this cognitive theory, physical rehabilitation incorporated into motor recovery of those therapeutic strategies that solicit the activation of the brain and/or symbolic processing; aspects that were not taken into account in mechanistic therapy. In addition, a classification into functionalist rehabilitation based on a computational therapy and a brain therapy will be shown. At the end of the article, the methodological principles in physical rehabilitation sciences will be explained. It will allow us to go deeper into the differences and similarities between therapeutic mechanism and therapeutic functionalism. [ABSTRACT FROM PUBLISHER]

PurposeTo determine whether gait training with a hybrid assistive limb (HAL) as an exoskeleton robotic device was safe and could increase functional mobility and gait ability in subacute stroke patients.MethodsThe participants were eight patients with post-stroke hemiparesis whose walking impairment and gait recovery curves had plateaued. The intervention program was gait training using HAL and a walker for 20 min daily 5 days a week for 5 weeks. The 10-m maximum walking speed (MWS), self-selected walking speed (SWS) and 2-min-walk test (2MT) without HAL were used as primary outcome measures to determine the effects of training. The Berg Balance Scale (BBS), Fugl-Meyer Assessment of Motor Recovery after Stroke (FMA) and functional ambulation category (FAC) were assessed as secondary outcomes. These measures were assessed before and after the 5-week intervention program and were analyzed statistically using a pairedt-test.ResultsAll eight participants completed the intervention program with no adverse events. There were significant increases in MWS, SWS and 2MT. BBS, FMA and FAC also increased, but not significantly.ConclusionThe new HAL exoskeleton robotic device was efficient and safe for improving motor function and gait in patients in the subacute stage after stroke.Implications for RehabilitationGait training using HAL will improve gait ability of individuals with post stroke.The HAL achieve intensive gait training without increase spasticity and abnormal gait pattern. [ABSTRACT FROM PUBLISHER]

Purpose: (1) To assess a robotic device (Handexos) during the design process with regard to usability, end user satisfaction and safety, (2) to determine whether Handexos can improve the activities of daily living (ADLs) of spinal cord injury (SCI) patients and stroke patients with upper-limb dysfunction.Methods: During a 2-year development stage of the device, a total of 37 participants (aged 22–68), 28 clinicians (experts) and nine patients with SCI or stroke (end users) were included in a user-centered design process featuring usability tests. They performed five grasps wearing the device. The assessments were obtained at the end of the session by filling out a questionnaire and making suggestions.Results: The experts’ opinion was that the modified device was an improvement over the preliminary version, although this was not reflected in the scores. Whereas end user scores for comfort, grasp, performance and safety were above the sufficiency threshold, the scores for year 2 were lower than those for year 1.Conclusions: The findings demonstrate that although Handexos meets the initial functional requirements and underlines the potential for assisting SCI and post-stroke subjects in ADLs, several aspects such as mechanical complexity and low adaptability to different hand sizes need to be further addressed.Implications for RehabilitationWearable robotics devices could improve the activities of daily living in patients with spinal cord injury or stroke.They could be a tool for rehabilitation of the upper limb.Further usability tests to improve this type of tools are recommended. [ABSTRACT FROM PUBLISHER]

Purpose: Robot-assisted gait training (RAGT) can complement conventional therapies in children with cerebral palsy. We investigated changes in walking-related outcomes between children with different Gross Motor Function Classification System (GMFCS) levels and the dose–response relationship. Methods: Data from 67 children (3.9–19.9 years) with GMFCS levels II–IV were evaluated retrospectively. Every child received RAGT with the Lokomat complementing a multidisciplinary rehabilitation program. Changes in various walking-related outcomes were assessed. Results: Walking-related outcomes did not improve differently between GMFCS level groups. Significant within-group improvements were mainly observed in children with GMFCS level IV. A dose–response relationship was present for children with GMFCS levels III and IV. Conclusions: Our results indicated that, although children with a GMFCS level IV walked less during an average Lokomat session, they experienced significant improvements in walking-related outcomes. Further, training dose correlated with changes in walking-related outcomes. However, between-group differences in changes in walking-related outcomes were not significant. [ABSTRACT FROM AUTHOR]

Purpose: Rehabilitation professionals have little information concerning lower limb exoskeletons for people with paraplegia. This study has four objectives: (1) Outline the characteristics of the exoskeletons’ design and their usefulness evidence as assistive mobility devices in the community for the Rewalk™, Mina, Indego®, Ekso™ (previously known as the eLEGS™) and Rex®; (2) document functional mobility outcomes of using these exoskeletons; (3) document secondary skills and benefits achieved with these exoskeletons, safety, user satisfaction and applicability in the community; and (4) establish level of scientific evidence of the selected studies.Method: A systematic review of the literature (January 2004 to April 2014) was done using the databases PubMed, CINAHL and Embase and groups of keywords associated with “exoskeleton”, “lower limb” and “paraplegia”.Results: Seven articles were selected. Exoskeleton use is effective for walking in a laboratory but there are no training protocols to modify identified outcomes over the term usage (ReWalk™: 3 months, Mina: 2 months and Indego®: 1 session). Levels of evidence of selected papers are low.Conclusions: The applicability and effectiveness of lower limb exoskeletons as assistive devices in the community have not been demonstrated. More research is needed on walking performance with these exoskeletons compared to other mobility devices and other training contexts in the community.Implications for rehabilitationCharacteristics of the exoskeletons’ design and their usefulness evidence as assistive mobility devices in the community are addressed for the Rewalk™, Mina, Indego®, Ekso™ and Rex® ReWalk™, Indego® and Mina lower limb exoskeletons are effective for walking in a laboratory for individuals with complete lower-level SCI.The ReWalk™ has the best results for walking, with a maximum speed of 0.51 m/s after 45 sessions lasting 60 to 120 min; it is comparable to the average speed per day or per week in a manual wheelchair.The level of scientific evidence is low. Other studies are needed to provide more information about performance over the longer term when walking with an exoskeleton, compared to wheelchair mobility, the user’s usual locomotion, the use of different exoskeletons or the training context in which the exoskeleton is used. [ABSTRACT FROM PUBLISHER]

Chronic neuropathic pain (CNP) is a common condition associated with spinal cord injury (SCI) and has been reported to be severe, disabling and often treatment-resistant and therefore remains a clinical challenge for the attending physicians. The treatment usually includes pharmacological and/or nonpharmacological approaches. Body weight supported treadmill training (BWSTT) and locomotion training with driven gait orthosis (DGO) have evolved over the last decades and are now considered to be an established part in the rehabilitation of SCI patients. Conventional locomotion training goes along with improvements of the patients' walking abilities in particular speed and gait pattern. The neurologic controlled hybrid assistive limb (HAL®, Cyberdyne Inc., Ibraki, Japan) exoskeleton, however, is a new tailored approach to support motor functions synchronously to the patient's voluntary drive. This report presents two cases of severe chronic and therapy resistant neuropathic pain due to chronic SCI and demonstrates the beneficial effects of neurologic controlled exoskeletal intervention on pain severity and health-related quality of life (HRQoL). Both of these patients were engaged in a 12 weeks period of daily HAL®-supported locomotion training. In addition to improvements in motor functions and walking abilities, both show significant reduction in pain severity and improvements in all HRQoL domains. Although various causal factors likely contribute to abatement of CNP, the reported results occurred due to a new approach in the rehabilitation of chronic spinal cord injury patients. These findings suggest not only the feasibility of this new approach but in conclusion, demonstrate the effectiveness of neurologic controlled locomotion training in the long-term management of refractory neuropathic pain.Implications for RehabilitationCNP remains a challenge in the rehabilitation of chronic SCI patients.Locomotion training with the HAL exoskeleton seems to improve CNP in chronic SCI.HAL locomotion training is feasible and safe in the rehabilitation of chronic SCI patients. [ABSTRACT FROM PUBLISHER]

This study presents apatient-specific muscle force estimation model(PMFE) for the potential use with swing-assist rehabilitation robots. This model employs a static optimization algorithm based on a computer-based musculoskeletal model, which provides patient-specific anthropometric parameters and muscle moment arms. Joint moments and muscle forces estimated by thecomputed muscle control(CMC) method using kinematic data from six healthy adolescents at their comfortable speed were used to evaluate the PMFE. The simulation results show that muscle forces estimated from the PMFE match well with those from the CMC, and the PMFE has significant computational efficiency (the entire swing phase takes only 0.02 s). As a case study, a novelpatient-specific biological command-based controller(PSBc), based on the PMFE, was developed to control a human-inspired swing-assist rehabilitation robot. The PSBc is evaluated by both simulation and robot experiment. The simulation results and the preliminary experiment results demonstrate that the PSBc could track both desired knee angles and desired forces. The results show the possibility of applying biomechanics methodology to the rehabilitation robot field. [ABSTRACT FROM PUBLISHER]

This paper describes an evaluation of muscle activity of volunteers while they undergo gait-like motion in their dorsal position supported by our lower-extremity motion simulator (LoMS) that is magnetic resonance imaging (MRI) compatible. Our LoMS is designed to provide gait-like motion for a wearer in his/her dorsal position while a functional MRI measures his/her brain activity. A purpose of providing gait-like motion by LoMS is to enable a wearer in the dorsal posture to move his/her lower extremities like gait. LoMS is controlled with torque control based on predictive control method to convert the gravity effect of the dorsal posture into the caudal posture. The performance providing gait-like motion is evaluated from two viewpoints of muscle activities: bioelectrical potential (BEP) transition and inhibition of musculus soleus during the motion. There were correlation of BEP transition at iliopsoas, quadriceps femoris, musculus tibialis anterior, and musculus soleus. The inhibition during the gait-like motion provided by LoMS was similar to the inhibition during treadmill gait. The inhibition is modulated by a level of cerebellum, brainstem and spinal. Therefore, it is considered that LoMS induces the motor sensation in the level of cerebellum, brainstem, and spinal by providing the gait-like motion. [ABSTRACT FROM PUBLISHER]

Purpose: To develop an aquatic exercise device to facilitate locomotive motor output and achieve repetitive physiological gait patterns to improve movement dysfunctions.Methods: A custom designed leg movement apparatus (LMA) consisted of closed 4-linkage mechanisms and one-length changeable link using a spring. Three-dimensional motions and electromyographic (EMG) activities were recorded in eight healthy subjects to evaluate the reproducibility of the physiological gait patterns using the LMA with or without a spring apparatus in water.Results: Using the LMA with a spring apparatus compared to walking in water, the foot trajectories and the time course of the elevation angles in each lower limb joint kinematics were preserved. The time-series of the EMG showed reciprocal modulation between agonist and antagonist muscle groups in the hip and ankle joints. However, the amplitudes of the tibialis anterior muscle in the first half and rectus femoris in the last half of the movement cycle were reduced using the LMA with a spring apparatus.Conclusion: We developed a novel aquatic exercise device to reproduce physiological gait patterns. The LMA with a spring apparatus would be particularly valuable in therapy for movement dysfunctions to facilitate locomotive motor outputs.Implications for RehabilitationThe leg movement apparatus with spring for underwater use (LMA) would be effective gait training to induce the locomotor-like EMG activities.Hydrotherapy with the LMA has advantages over the partial body weight support treadmill training on land with a robotic device; (1) the LMA is electrically and mechanically safe, and (2) the LMA would require self-effort to generate the gait pattern for movement disorders, or also enable passive gait training by the physiotherapists. [ABSTRACT FROM PUBLISHER]

Many systems and control methods have been proposed as mobility supports for the physically disabled and elderly individuals. In this research, we focus on a wearable-type system that supports the elderly with their walking. Different from typical control methods of wearable-type walking support systems, we propose a simple control method based on the spring–mass model. As a walking aid that does not require additional motions, such as sit-to-stand, this simple system is beneficial for two reasons. First, it reduces the calculation cost of deriving the support joint torque of the user; second, the wearable device hardware can be simply constructed from low-power actuators and springs rather than high-power actuators. In stance phase support mode, our motion control method compensates for a part of the force applied to the upper body as a leg muscle support. During the swing phase, walking is supported by a trajectory-following method using the impedance control as well as the spring–mass model. The proposed methods are applied to a prototype of a wearable-type walking support system, and evaluated in a series of experiments on human subjects. [ABSTRACT FROM AUTHOR]

The authors explored task-specific stability during accurate multifinger force production tasks with different numbers of instructed fingers. Subjects performed steady-state isometric force production tasks and were instructed not to interfere voluntarily with transient lifting-and-lowering perturbations applied to the index finger. The main results were (a) intertrial variance in the space of finger modes at steady states was larger within the subspace that had no effect on the total force (the uncontrolled manifold [UCM]); (b) perturbations caused large deviations of finger modes within the UCM (motor equivalence); and (c) deviations caused by the perturbation showed larger variance within the UCM. No significant effects of the number of task fingers were noted in any of the 3 indicators. The results are discussed within the frameworks of the UCM and referent configuration hypotheses. The authors conclude, in particular, that all the tasks were effectively 4-finger tasks with different involvement of task and nontask fingers. [ABSTRACT FROM AUTHOR]

This paper presents a novel voltage-based adaptive impedance force control for a lower limb rehabilitation robot. The impedance parameters are adaptively regulated by a gradient descent algorithm for adjusting the human force in performing therapeutic exercises. Although the proposed control is based on voltage control strategy, it differs from the common torque control strategy. One of the advantages is that it is free from the dynamical models of the robot and patient. Compared with a torque control scheme, it is simpler, less computational, and more efficient while it considers the actuators. The control approach is verified by stability analysis. Simulation results show the efficiency of the control approach applied on a lower limb rehabilitation robot driven by an electric motor. A comparison on performing isometric exercise shows that the voltage-based adaptive impedance force control is superior to both voltage-based impedance control and torque-based impedance control. [ABSTRACT FROM AUTHOR]