Man-Machine Interface System for Neuromuscular Training and Evaluation Based on EMG and MMG Signals

This paper presents the UVa-NTS (University of Valladolid Neuromuscular Training System), a multifunction and portable Neuromuscular Training System. The UVa-NTS is designed to analyze the voluntary control of severe neuromotor handicapped patients, their interactive response, and their adaptation to neuromuscular interface systems, such as neural prostheses or domotic applications. Thus, it is an excellent tool to evaluate the residual muscle capabilities in the handicapped. The UVa-NTS is composed of a custom signal conditioning front-end and a computer. The front-end electronics is described thoroughly as well as the overall features of the custom software implementation. The software system is composed of a set of graphical training tools and a processing core. The UVa-NTS works with two classes of neuromuscular signals: the classic myoelectric signals (MES) and, as a novelty, the myomechanic signals (MMS). In order to evaluate the performance of the processing core, a complete analysis has been done to classify its efficiency and to check that it fulfils with the real-time constraints. Tests were performed both with healthy and selected impaired subjects. The adaptation was achieved rapidly, applying a predefined protocol for the UVa-NTS set of training tools. Fine voluntary control was demonstrated to be reached with the myoelectric signals. And the UVa-NTS demonstrated to provide a satisfactory voluntary control when applying the myomechanic signals

Feasibility of Muscle Synergy Outcomes in Clinics, Robotics, and Sports: A Systematic Review

In the last years, several studies have been focused on understanding how the central nervous system controls muscles to perform a specific motor task. Although it still remains an open question, muscle synergies have come to be an appealing theory to explain the modular organization of the central nervous system. Even though the neural encoding of muscle synergies remains controversial, a large number of papers demonstrated that muscle synergies are robust across different tested conditions, which are within a day, between days, within a single subject and between subjects that have similar demographic characteristics. Thus, muscle synergy theory has been largely used in several research fields, such as clinics, robotics and sports. The present systematical review aims at providing an overview on the applications of muscle synergy theory in clinics, robotics and sports; in particular, the review is focused on the papers that provide tangible information for: (i) diagnosis or pathology assessment in clinics; (ii) robot-control design in robotics; and (iii) athletes’ performance assessment or training guidelines in sports

A New Labeling Approach for Proportional Electromyographic Control

Different control strategies are available for human machine interfaces based on electromyography (EMG) to map voluntary muscle signals to control signals of a remote controlled device. Complex systems such as robots or multi-fingered hands require a natural commanding, which can be realized with proportional and simultaneous control schemes. Machine learning approaches and methods based on regression are often used to realize the desired functionality. Training procedures often include the tracking of visual stimuli on a screen or additional sensors, such as cameras or force sensors, to create labels for decoder calibration. In certain scenarios, where ground truth, such as additional sensor data, can not be measured, e.g., with people suffering from physical disabilities, these methods come with the challenge of generating appropriate labels. We introduce a new approach that uses the EMG-feature stream recorded during a simple training procedure to generate continuous labels. The method avoids synchronization mismatches in the labels and has no need for additional sensor data. Furthermore, we investigated the influence of the transient phase of the muscle contraction when using the new labeling approach. For this purpose, we performed a user study involving 10 subjects performing online 2D goal-reaching and tracking tasks on a screen. In total, five different labeling methods were tested, including three variations of the new approach as well as methods based on binary labels, which served as a baseline. Results of the evaluation showed that the introduced labeling approach in combination with the transient phase leads to a proportional command that is more accurate than using only binary labels. In summary, this work presents a new labeling approach for proportional EMG control without the need of a complex training procedure or additional sensors

Biomechatronics: Harmonizing Mechatronic Systems with Human Beings

This eBook provides a comprehensive treatise on modern biomechatronic systems centred around human applications. A particular emphasis is given to exoskeleton designs for assistance and training with advanced interfaces in human-machine interaction. Some of these designs are validated with experimental results which the reader will find very informative as building-blocks for designing such systems. This eBook will be ideally suited to those researching in biomechatronic area with bio-feedback applications or those who are involved in high-end research on manmachine interfaces. This may also serve as a textbook for biomechatronic design at post-graduate level

Recovery of arm-hand function after stroke: developing neuromechanical biomarkers to optimize rehabilitation strategies.

The aim of this thesis was to explore the neuromechanics of recovery of arm-hand function after stroke. A literature review revealed six articles that measured biomechanical and electromyographical outcome measures simultaneously, while applying active and passive tasks and multiple movement velocities to separate neural and non-neural contributors to movement disorders after stroke. Therefore, a neuromechanic assessment protocol was developed. Parameters were responsive to clinical status and had good to excellent test-retest reliability. Selective muscle activation was assessed with high measurement reliability and was significantly lower in chronic stroke patients compared to healthy participants. Longitudinally, neuromechanical parameters were combined with data on arm-hand function at six months after stroke. Paresis and diminished modulation of reflexes were associated with poor functional outcome. Changes in tissue properties were represented by a shift in wrist rest angle towards flexion and decline in passive range of motion. Increase in active range of motion and steady rest angle contributed most to prediction of functional outcome. The precision diagnostics provided by a neuromechanical assessment protocol could support clinical decision making and should be used in prediction models and as biomarkers in recovery of arm-hand function after stroke, for example by improving the selection of time-window and patients.ZON/MW grant 89000001LUMC / Geneeskund

Aerospace Medicine and Biology: A continuing bibliography with indexes (supplement 248)

This bibliography lists 364 reports, articles and other documents introduced into the NASA scientific and technical information system in July 1983

The effect of shoulder stability training on upper limb function and quality of life in patients with hemiplegia

A dissertation submitted to the Faculty of Health Sciences, University of the Witwatersrand, in fulfilment of the requirements for the degree of Master of Science in Physiotherapy Johannesburg, 2016INTRODUCTION Stroke is a major cause of mortality and long-term adult disability and has a significant physical and psychosocial impact on individuals and their Health-Related Quality of Life (HRQoL). The loss of upper limb function post-stroke directly impacts on shoulder girdle stability of the affected side. Shoulder girdle stability is essential for optimal functioning of the upper limb; good shoulder function is a prerequisite for effective hand function and the execution of the expected tasks with regard to activities of daily living (ADL). It is well known that the rehabilitation of the upper limb post-stroke remains challenging. AIM The aim of the study was to determine the effect of shoulder stability training using the Biodex Balance System (BBS) on shoulder girdle stability, upper-limb function, pain control and HRQoL in patients with hemiplegia post-stroke. METHODS The study utilised a quantitative longitudinal randomised control trial design with single blinding. Participants who met the inclusion criteria and who gave informed consent were assigned to one of two groups, the experimental or the control group, using computer-generated random numbers with concealed allocation. Participants were included in the study if they met the following criteria: were either male or female patients, who had a stroke, resulting in hemiplegia and/or shoulder instability, and were between the ages of 18 and 85 years. In addition to usual care, shoulder girdle stability training using the BBS was given to the participants in the experimental group. Assessments were done at baseline and one, three and six month’s post-baseline. All the participants were assessed by the research assistant using the following: pain measured by the Wong-Baker FACES Pain Rating Scale, the functionality of the upper limb measured by the Fugl-Meyer Assessment Upper Extremity, the shoulder girdle stability measured by the Postural Stability Test on the BBS and HRQoL measured by the SF-36v2 Health Survey. RESULTS AND DISCUSSION A total of 17 participants were included in the main study after screening and, 53% were males. The median age of the study sample was 53 years. The control group comprised more female (n=5) than male (n=2) participants, while the experimental group comprised more male (n=7) than female (n=3) participants. All the participants in the control group were right-handed implying that more of them had their dominant hand affected than those in the experimental group. At baseline the two groups were comparable with regard to shoulder girdle stability, upper limb function and the HRQoL, but were not comparable regarding pain, as the control group experienced significantly more pain than the experimental group. There were no statistically significant differences between the two groups with regard to shoulder girdle stability on any of the three BBS stability levels neither at the baseline (p=0.69) nor at one-month follow-up post-baseline (p=0.77). There was no significant difference in upper limb function (baseline p=0.5, one month follow-up post-baseline p=0.93) between the control and the experimental groups for the entire study period. The severity of the impairment of upper limb function for both the control and the experimental group was comparable at baseline and improved from moderate (56-79) to mild (>79) during the duration of the study. At baseline the participants in the control group already expierienced more pain than the experimental group (p=0.05). Participants in the control group experienced significantly more shoulder pain than the experimental group at the one-month followup (p=0.02), but no differences were found at the three- (p=0.17) and sixmonths( p=0.12) follow-up post-baseline. At baseline a statistically significant difference was found regarding the impact of emotional problems on role limitation (p = 0.03) and pain (p = 0.05) between the two groups, with the control group indicating lower scores than the experimental group. At one month a statistically significant difference was found between the two groups regarding the extent of impaired social functioning (p = 0.05). The participants in the experimental group reported improvement in their health over time (baseline = 67.5 and six-month follow-up post baseline = 86.11). None of the factors investigated in this study impacted on HRQoL outcomes over time. CONCLUSION Shoulder girdle stability training using the BBS did not result in significant improvements in shoulder girdle stability, upper limb function, pain relief and HRQoL post-stroke in this cohort. The findings in this study could have been influenced by the small sample size (the power calculation was done only for the shoulder girdle stability) and also by participants in the control and experimental group continuing with their standard care, which included an intensive rehabilitation programme. This could have been a confounding factor impacting on the outcome. Further research in this field is required.MT201

Aerospace medicine and biology: A continuing bibliography with indexes (supplement 342)

This bibliography lists 208 reports, articles and other documents introduced into the NASA Scientific and Technical Information System during October 1990. Subject coverage includes: aerospace medicine and psychology, life support systems and controlled environments, safety equipment, exobiology and extraterrestrial life, and flight crew behavior and performance

Cognitive Reasoning for Compliant Robot Manipulation

Physically compliant contact is a major element for many tasks in everyday environments. A universal service robot that is utilized to collect leaves in a park, polish a workpiece, or clean solar panels requires the cognition and manipulation capabilities to facilitate such compliant interaction. Evolution equipped humans with advanced mental abilities to envision physical contact situations and their resulting outcome, dexterous motor skills to perform the actions accordingly, as well as a sense of quality to rate the outcome of the task. In order to achieve human-like performance, a robot must provide the necessary methods to represent, plan, execute, and interpret compliant manipulation tasks. This dissertation covers those four steps of reasoning in the concept of intelligent physical compliance. The contributions advance the capabilities of service robots by combining artificial intelligence reasoning methods and control strategies for compliant manipulation. A classification of manipulation tasks is conducted to identify the central research questions of the addressed topic. Novel representations are derived to describe the properties of physical interaction. Special attention is given to wiping tasks which are predominant in everyday environments. It is investigated how symbolic task descriptions can be translated into meaningful robot commands. A particle distribution model is used to plan goal-oriented wiping actions and predict the quality according to the anticipated result. The planned tool motions are converted into the joint space of the humanoid robot Rollin' Justin to perform the tasks in the real world. In order to execute the motions in a physically compliant fashion, a hierarchical whole-body impedance controller is integrated into the framework. The controller is automatically parameterized with respect to the requirements of the particular task. Haptic feedback is utilized to infer contact and interpret the performance semantically. Finally, the robot is able to compensate for possible disturbances as it plans additional recovery motions while effectively closing the cognitive control loop. Among others, the developed concept is applied in an actual space robotics mission, in which an astronaut aboard the International Space Station (ISS) commands Rollin' Justin to maintain a Martian solar panel farm in a mock-up environment. This application demonstrates the far-reaching impact of the proposed approach and the associated opportunities that emerge with the availability of cognition-enabled service robots