Development Of Assist Devices Research Articles

Assistive devices for the people with disabilities enabled by triboelectric nanogenerators

According to data released by the World Health Organization, more than one billion people in the world experience some form of disability, in which they face all kinds of inconveniences. As a practical tool to help people with disabilities participate in social life, assistive devices for the people with disabilities play an important role in their daily lives. As an effective electromechanical signal conversion technology, triboelectric nanogenerator (TENG) has been successfully applied to various types of biosensors. This review aims to provide an overview of the development of assistive devices for the people with disabilities based on TENG with five categories: hearing, vision, pronunciation, gustation and limb/joint, according to the classification method of the impaired part. Meanwhile, a human–computer interaction system for the people with disabilities is also investigated. Finally, the prospect and potential challenges of this new field are discussed.

Development and control of a home-based training device for hand rehabilitation with a spring and cable driven mechanism.

Rehabilitation at home is rapidly increasing. Although successful results are achieved with treatment methods applied in rehabilitation clinics, there are also some disadvantages in this process, such as dependence on an expert and high costs. Developments in mechatronic technologies have accelerated the development of assistive devices which are designed for use at home. One of the rehabilitation applications is on a hemiplegic hand. In previous studies, some useful devices have been developed for hand rehabilitation. In this study, we suggest a new, low-cost and wearable robotic glove for hand rehabilitation. The specific component of this device is the spring and cable driven system proposed for transmission of motion and force. The device was tested on both unimpaired participants and patients with the hemiplegic hand, and it was proven to be beneficial for hand rehabilitation. As a result of trials with unimpaired participants, the muscle activation of the extensor digitorum and the flexor carpi radialis were increased by 184.1 and 197.8% respectively. The weight of the device was less than 400g, thanks to 3D printed parts.

Real-Time Assessment of Causal Attribution Shift and Stay Between Two Successive Tests of Movement Aids

The development of welfare assistive devices for frail elderly people has attracted significant attention for its effort to improve the quality of life and reduce the burden on caregivers. However, it is challenging to conduct multiple user tests because of the significant burden on the elderly; thus, we need efficient ways to extract insight through different approaches. In this study, we aim to elucidate real-time transitions in users’ emotions and achievement motivation while using such a device. We synthesize an utterance analysis method based on attribution theory, in which all users’ utterances are attributed to four categories (ability, effort, task difficulty, and luck) that follow the developed coding rules. Knowing the transitions in causal attribution allows us to extract salient experiences for users, especially by extracting shifts from them and analyzing why the shift occurred and what exactly was happening before and after the shift. If only salient user experiences can be referenced from the aggregate data, useful information can be extracted in a short time to improve system characteristics and the environment. We discussed the validity and reliability of the proposed method by conducting a user test of an electric-assisted four-wheeled cycle for frail elderly people in Kakegawa city in Shizuoka, Japan. We also succeeded in marking the points that need attention, which is about 33% of the total amount of utterance data (1626 utterances), and thus confirmed the potential of the proposed method. Future research should examine how the developed methodology can help designers improve assistive device development, as well as how it can contribute to other fields such as education and social assistance.

A Smart Parametric 3D Printing Hand Assistive Device With a Practical Physically Intervention Feedback Based on the Embedded IMU Sensor

Assistive devices are one of the crucial medical instruments for rehabilitation. Customized designs are required to match the geometry and dimensions of the affected sites of human bodies. The existing practice of assistive device development remains mostly a manual process, in which an experienced physiotherapist employs simple two-dimensional measurements and visual estimation to handcraft each device. The resulting devices not only vary substantially in fit to wearers, but also are not compatible to modern developmental technologies such as three-dimensional (3D) printing. This study incorporated substantial quantities of anthropometric data to construct a parametric 3D hand model. This study employed a customized assistive device - splint for carpal tunnel syndrome as a target object for testing the feasibility of the proposed method and verified the practicability through 3D printing implementation. Moreover, a wearable device embedded with inertial measurement unit sensor and vibration module will be integrated into the customized assistive device to offer a smart way for rehabilitation. With the help of this developed wearable device, continuously tracking user’s activity wirelessly and provide the real-time physically intervention feedback of vibration module based on back-end monitoring system platform. This new concept by integrating customized design and the IMU sensor and vibration module open a new window for the field of customized assistive device and improve its practical values.

Joint-Development Of Mobility Assistive Devices For Patients With Special Treatment

The skeletal, muscular and nervous systems in human body works together to enable specific movement or posture. Abnormalities in any of these systems may cause this functionality to degrade. Some examples of such diseases are spinal muscular atrophy and celebral palsy. Patients who suffer from these diseases may require assistive devices designed specifically to their anatomy for supporting their posture and mobility. Bioteknik Design in Bandung, is a small local company focusing in the development of assistive device for helping such patients. A collaboration between SGU and Bioteknik was made to help Bioteknik in designing some of their supportive devices. A student internship was assigned in Bioteknik Design to conduct various tasks related to developing assistive devices based on the need of the patient. These tasks include patient anatomy measurement, design and production of the assistive devices suitable for the patient. These tasks are directed towards giving the patient the mobility and the posture needed, so that the opportunity for the patient to move, explore, and connect to their surroundings could be improved. In this project, several assistive devices, e.g. electrical wheelchair (Go-Roll), specific wheel chair with footrest, and feet-controlled wheelchair, have been measured, design and implemented at various stages.

AT-d8sign: methodology to support development of assistive devices focused on user-centered design and 3D technologies

AT-d8sign: methodology to support development of assistive devices focused on user-centered design and 3D technologies

Predicting Perturbed Human Arm Movements in a Neuro-Musculoskeletal Model to Investigate the Muscular Force Response.

Human movement is generated by a dynamic interplay between the nervous system, the biomechanical structures, and the environment. To investigate this interaction, we propose a neuro-musculoskeletal model of human goal-directed arm movements. Using this model, we simulated static perturbations of the inertia and damping properties of the arm, as well as dynamic torque perturbations for one-degree-of freedom movements around the elbow joint. The controller consists of a feed-forward motor command and feedback based on muscle fiber length and contraction velocity representing short-latency (25 ms) or long-latency (50 ms) stretch reflexes as the first neuronal responses elicited by an external perturbation. To determine the open-loop control signal, we parameterized the control signal resulting in a piecewise constant stimulation over time for each muscle. Interestingly, such an intermittent open-loop signal results in a smooth movement that is close to experimental observations. So, our model can generate the unperturbed point-to-point movement solely by the feed-forward command. The feedback only contributed to the stimulation in perturbed movements. We found that the relative contribution of this feedback is small compared to the feed-forward control and that the characteristics of the musculoskeletal system create an immediate and beneficial reaction to the investigated perturbations. The novelty of these findings is (1) the reproduction of static as well as dynamic perturbation experiments in one neuro-musculoskeletal model with only one set of basic parameters. This allows to investigate the model's neuro-muscular response to the perturbations that—at least to some degree—represent stereotypical interactions with the environment; (2) the demonstration that in feed-forward driven movements the muscle characteristics generate a mechanical response with zero-time delay which helps to compensate for the perturbations; (3) that this model provides enough biomechanical detail to allow for the prediction of internal forces, including joint loads and muscle-bone contact forces which are relevant in ergonomics and for the development of assistive devices but cannot be observed in experiments.

A biarticular passive exosuit to support balance control can reduce metabolic cost of walking

Nowadays, the focus on the development of assistive devices just for people with mobility disorders has shifted towards enhancing physical abilities of able-bodied humans. As a result, the interest in the design of cheap and soft wearable exoskeletons (called exosuits) is distinctly growing. In this paper, a passive lower limb exosuit with two biarticular variable stiffness elements is introduced. These elements are in parallel to the hamstring muscles of the leg and controlled based on a new version of the FMCH (force modulated compliant hip) control framework in which the force feedback is replaced by the length feedback (called LMCH). The main insight to employ leg length feedback is to develop a passive exosuit. Fortunately, similar to FMCH, the LMCH method also predicts human-like balance control behaviours, such as the VPP (virtual pivot point) phenomenon, observed in human walking. Our simulation results, using a neuromuscular model of human walking, demonstrate that this method could reduce the metabolic cost of human walking by 10%. Furthermore, to validate the design and simulation results, a preliminary version of this exosuit comprised of springs with constant stiffness was built. An experiment with eight healthy subjects was performed. We made a comparison between the walking experiments while the exosuit is worn but the springs were slack and those when the appropriate springs were contributing. It shows that passive biarticular elasticity can result in a metabolic reduction of 14.7 4.27%. More importantly, compared to unassisted walking (when exosuit is not worn), such a passive device can reduce walking metabolic cost by 4.68 4.24%.

Development of assistive devices to support posture for spinal cord injury persons when driving a vehicle

Development of assistive devices to support posture for spinal cord injury persons when driving a vehicle

Decoding Movement From Electrocorticographic Activity: A Review.

Electrocorticography (ECoG) holds promise to provide efficient neuroprosthetic solutions for people suffering from neurological disabilities. This recording technique combines adequate temporal and spatial resolution with the lower risks of medical complications compared to the other invasive methods. ECoG is routinely used in clinical practice for preoperative cortical mapping in epileptic patients. During the last two decades, research utilizing ECoG has considerably grown, including the paradigms where behaviorally relevant information is extracted from ECoG activity with decoding algorithms of different complexity. Several research groups have advanced toward the development of assistive devices driven by brain-computer interfaces (BCIs) that decode motor commands from multichannel ECoG recordings. Here we review the evolution of this field and its recent tendencies, and discuss the potential areas for future development.

GRID: a model for the development of assistive devices in developing countries

Purpose An” Appropriate Assistive Device” is accessible, affordable and standardised in terms of quality and safety, and most importantly, has the functionality to satisfy the user needs. The cost of research and development (R&D) of such assistive products for a market that has limited purchasing power is a significant hurdle and traditional models of R&D may not work effectively in this case. This paper presents an experience-based viable model for the R&D of assistive devices for users in developing countries. Method The model presented here has been evolved from the functioning of the TTK Centre for Rehabilitation Research and Device Development (R2D2) in IIT Madras, Chennai, India. The model is based on the four pillars of Grants-Research-Industry-Dissemination, hence the name GRID model. We have been effectively using this model involving academia, funding agencies, industry partners and users to develop appropriate assistive devices. Three case studies of assistive device development based on the GRID model are presented in this paper to elucidate practical implementation of the model. Results Using the GRID model, we have successfully accomplished the development of appropriate assistive devices and two of these devices will be launched in the coming months. Conclusions The proposed GRID model is a viable model for the development of appropriate assistive devices in developing countries, and could likely be replicated in other parts of the world as well. IMPLICATIONS FOR REHABILITATION The GRID model is practically viable and provides a systematic approach for the development of high-quality, functional and affordable assistive devices. Implementation of the GRID model to develop assistive devices could attract more funding and committed stakeholders to this space, with the potential to change the assistive device landscape in developing countries by making available more functional and affordable devices. In effect, the model will benefit users of assistive devices by giving them a greater choice of available devices and empowering them to lead a quality life.

Age-related injury risk curves for the lumbar spine for use in low-back-pain prevention in manual handling tasks

This study introduces injury risk curves for the lumbar spine for use in the risk assessment of low back pain (LBP) caused by manual lifting of heavy loads. LBP has been a longstanding problem among industrial workers, giving rise to the development of assistive devices. However, quantitative evaluation methods to verify the safety of such devices have not yet been established. The notable biomechanical criterion of 3.4 kN of lumbar compressive force, defined by the National Institute for Occupational Safety and Health, applies only to young, healthy workers with a fixed risk level. This study on injury risk curves clarified the risk level of injury to the lumbar spine due to lumbar compressive force for individuals within a wide age range. The findings can be applied for the design and evaluation of assistive devices as well as the design of ergonomic guidelines for manual work.

Articulatory and bottleneck features for speaker-independent ASR of dysarthric speech

The rapid population aging has stimulated the development of assistive devices that provide personalized medical support to the needies suffering from various etiologies. One prominent clinical application is a computer-assisted speech training system which enables personalized speech therapy to patients impaired by communicative disorders in the patient’s home environment. Such a system relies on the robust automatic speech recognition (ASR) technology to be able to provide accurate articulation feedback. With the long-term aim of developing off-the-shelf ASR systems that can be incorporated in clinical context without prior speaker information, we compare the ASR performance of speaker-independent bottleneck and articulatory features on dysarthric speech used in conjunction with dedicated neural network-based acoustic models that have been shown to be robust against spectrotemporal deviations. We report ASR performance of these systems on two dysarthric speech datasets of different characteristics to quantify the achieved performance gains. Despite the remaining performance gap between the dysarthric and normal speech, significant improvements have been reported on both datasets using speaker-independent ASR architectures.

Assistive technologies for improving the oral hygiene of leprosy patients residing in a former leprosy colony in Betim, Minas Gerais, Brazil.

BackgroundThis study deals with management of a group of elderly patients with a history of leprosy and hand deformities by a multidisciplinary team of dentists and occupational therapists. Assistive technology devices have been developed to allow such patients to obtain independence in oral self-care and can be a cost-effective approach to improving oral care in this population. The objective of this study was to describe the development of assistive devices to facilitate daily oral hygiene in older people with enduring leprosy-related impairments.MethodologyCase study realized among elders with a history of leprosy residents in a former isolation colony in Betim, Minas Gerais, Brazil. The elders were evaluated for dependence on others for denture hygiene and mouthwash using the Daily Oral Hygiene Activity Index (ADOH). Those deemed partially or completely dependent on others were eligible for an intervention based on assistive technology. We adopted a personalized approach to each case, taking into account medical history, physical impairment and living environment. Six months after the intervention, the participants were assessed again using the ADOH and an unstructured interview about use of the devices.Principal findingsAssistive devices for denture hygiene and mouthwash were developed for 16 elders. These devices facilitated oral hygiene in most patients and there was no worsening in any of the cases. Patients’ report suggested they were satisfied with the devices provided.ConclusionsThis study demonstrated that assistive devices can facilitate oral hygiene activities in leprosy patients. It also reinforces the importance of using a multidisciplinary team for the rehabilitation of these patients.

Influence of talker discontinuity on cortical dynamics of auditory spatial attention

In everyday acoustic scenes, listeners face the challenge of selectively attending to a sound source and maintaining attention on that source long enough to extract meaning. This task is made more daunting by frequent perceptual discontinuities in the acoustic scene: talkers move in space and conversations switch from one speaker to another in a background of many other sources. The inherent dynamics of such switches directly impact our ability to sustain attention. Here we asked how discontinuity in talker voice affects the ability to focus auditory attention to sounds from a particular location as well as neural correlates of underlying processes. During electroencephalography recordings, listeners attended to a stream of spoken syllables from one direction while ignoring distracting syllables from a different talker from the opposite hemifield. On some trials, the talker switched locations in the middle of the streams, creating a discontinuity. This switch disrupted attentional modulation of cortical responses; specifically, event-related potentials evoked by syllables in the to-be-attended direction were suppressed and power in alpha oscillations (8–12 Hz) were reduced following the discontinuity. Importantly, at an individual level, the ability to maintain attention to a target stream and report its content, despite the discontinuity, correlates with the magnitude of the disruption of these cortical responses. These results have implications for understanding cortical mechanisms supporting attention. The changes in the cortical responses may serve as a predictor of how well individuals can communicate in complex acoustic scenes and may help in the development of assistive devices and interventions to aid clinical populations.

Modulation of lower extremity joint stiffness, work and power at different walking and running speeds

Locomotion task and speed changes affect dynamic joint function. Walking and running require different coordination patterns of lower extremity joint mechanics. These coordination differences can result in measurable changes in kinematic and kinetic patterns. When locomotion speed changes, the functional role and movement strategy of each joint is altered. A deeper understanding of joint level mechanics and functional interactions will benefit rehabilitation programs and assistive device development. In this study, joint stiffness, joint mechanical work and power were assessed, as they relate to dynamic function of joints during locomotion. Ten young healthy subjects (5 males, 5 females) participated in a treadmill walking (0.8–2.0 m/s) and running (1.8–3.8 m/s) study. When running speed increased, the stiffness of all three joints tended to increase. The ankle joint played a dominant role during the stance phase of running, generating more positive work than the knee (p = .003) and hip (p = .0001). The knee and hip joint were more dominant in walking and running swing phase energy absorption and generation, respectively. When locomotion speeds increased, stance phase ankle positive work, swing phase knee negative work, and hip joint positive work tended to increase. These findings suggest that change of locomotion speed or task results in definitive changes to lower extremity joint level mechanics patterns.

Development of Assistive Device with Variable Viscoelastic Joint

Development of Assistive Device with Variable Viscoelastic Joint

Survey of the functional priorities in patients with disability due to neuromuscular disorders

Title: Survey of the functional priorities in patients with disability due to neuromuscular disorders.Objective: This study attempts to determine the functional priorities for patients with neuromuscular disorders.Methods: A survey asking about functional priorities with respect to activities of daily living, ankle foot orthotic design, and assistive device design, was distributed to patients with neuromuscular disorders to assess the needs of patients from their perspectives. Descriptive statistics were used to analyse answers.Results: A total of 171 subjects with neuromuscular disorders responded to the questionnaire. Of the respondents with weakness in both the upper and lower extremities, 45% stated that if they had to choose between correction of one or the other, they would prefer that of their lower extremities. Activities that patients most frequently wanted to gain independence with were mobility and transfers (46%), followed by toilet use and hygiene (32%). The most popular control mechanism of an assistive device was voice activation (35%).Conclusion: This study assessed the functional priorities of those with neuromuscular disorders. Although such individuals can experience a range of weakness in the upper and/or lower extremities, common functional priorities were reported: independence with mobility, transfers, toilet use and hygiene. Knowledge of these priorities will help guide development of assistive devices that will restore function in the future.Implications for Rehabilitation Neuromuscular Disorders • Neuromuscular disorders result in disabling weakness; there are few cures and many are unable to carry out activities of daily living. • Information that would be helpful in determining functional priorities is limited. • In a survey of 171 patients with neuromuscular disorders, functional priorities included mobility and transfers (46%), followed by toilet use and hygiene (32%). • Of the respondents with weakness in both the upper and lower extremities, 45% stated that if they had to choose between correction of one or the other, they would prefer that of their lower extremities. • If an assistive device were to be created to help those with neuromuscular disorders, the most popular control mechanism would be voice activation (35%).

A Hybrid FPGA-Based System for EEG- and EMG-Based Online Movement Prediction.

A current trend in the development of assistive devices for rehabilitation, for example exoskeletons or active orthoses, is to utilize physiological data to enhance their functionality and usability, for example by predicting the patient’s upcoming movements using electroencephalography (EEG) or electromyography (EMG). However, these modalities have different temporal properties and classification accuracies, which results in specific advantages and disadvantages. To use physiological data analysis in rehabilitation devices, the processing should be performed in real-time, guarantee close to natural movement onset support, provide high mobility, and should be performed by miniaturized systems that can be embedded into the rehabilitation device. We present a novel Field Programmable Gate Array (FPGA) -based system for real-time movement prediction using physiological data. Its parallel processing capabilities allows the combination of movement predictions based on EEG and EMG and additionally a P300 detection, which is likely evoked by instructions of the therapist. The system is evaluated in an offline and an online study with twelve healthy subjects in total. We show that it provides a high computational performance and significantly lower power consumption in comparison to a standard PC. Furthermore, despite the usage of fixed-point computations, the proposed system achieves a classification accuracy similar to systems with double precision floating-point precision.

Statistical Shape Modeling for Cavopulmonary Assist Device Development: Variability of Vascular Graft Geometry and Implications for Hemodynamics.

Patients born with a single functional ventricle typically undergo three-staged surgical palliation in the first years of life, with the last stage realizing a cross-like total cavopulmonary connection (TCPC) of superior and inferior vena cavas (SVC and IVC) with both left and right pulmonary arteries, allowing all deoxygenated blood to flow passively back to the lungs (Fontan circulation). Even though within the past decades more patients survive into adulthood, the connection comes at the prize of deficiencies such as chronic systemic venous hypertension and low cardiac output, which ultimately may lead to Fontan failure. Many studies have suggested that the TCPC's inherent insufficiencies might be addressed by adding a cavopulmonary assist device (CPAD) to provide the necessary pressure boost. While many device concepts are being explored, few take into account the complex cardiac anatomy typically associated with TCPCs. In this study, we focus on the extra cardiac conduit vascular graft connecting IVC and pulmonary arteries as one possible landing zone for a CPAD and describe its geometric variability in a cohort of 18 patients that had their TCPC realized with a 20mm vascular graft. We report traditional morphometric parameters and apply statistical shape modeling to determine the main contributors of graft shape variability. Such information may prove useful when designing CPADs that are adapted to the challenging anatomical boundaries in Fontan patients. We further compute the anatomical mean 3D graft shape (template graft) as a representative of key shape features of our cohort and prove this template graft to be a significantly better approximation of population and individual patient's hemodynamics than a commonly used simplified tube geometry. We therefore conclude that statistical shape modeling results can provide better models of geometric and hemodynamic boundary conditions associated with complex cardiac anatomy, which in turn may impact on improved cardiac device development.