Mobility Assistive Devices Research Articles

A conceptual framework to assess effectiveness in wheelchair provision.

BackgroundCurrently, inadequate wheelchair provision has forced many people with disabilities to be trapped in a cycle of poverty and deprivation, limiting their ability to access education, work and social facilities. This issue is in part because of the lack of collaboration among various stakeholders who need to work together to design, manufacture and deliver such assistive mobility devices. This in turn has led to inadequate evidence about intervention effectiveness, disability prevalence and subsequent costeffectiveness that would help facilitate appropriate provision and support for people with disabilities.ObjectivesIn this paper, we describe a novel conceptual framework that can be tested across the globe to study and evaluate the effectiveness of wheelchair provision.MethodThe Comparative Effectiveness Research Subcommittee (CER-SC), consisting of the authors of this article, housed within the Evidence-Based Practice Working Group (EBP-WG) of the International Society of Wheelchair Professionals (ISWP), conducted a scoping review of scientific literature and standard practices used during wheelchair service provision. The literature review was followed by a series of discussion groups.ResultsThe three iterations of the conceptual framework are described in this manuscript.ConclusionWe believe that adoption of this conceptual framework could have broad applications in wheelchair provision globally to develop evidence-based practices. Such a perspective will help in the comparison of different strategies employed in wheelchair provision and further improve clinical guidelines. Further work is being conducted to test the efficacy of this conceptual framework to evaluate effectiveness of wheelchair service provision in various settings across the globe.

Design and characterization of a hyperelastic tubular soft composite.

Research in the field of human mobility assistive devices, aiming to reduce the metabolic cost of daily activities, is seeing the benefits of the exclusive use of passive actuators to store and release energy during the gait cycle. Current devices commonly employ either mechanical springs or Pneumatic Artificial Muscles as the primary method of passive actuation. The Pneumatic Artificial Muscle has proven to be a superior actuation choice for these devices, when compared to its alternatives. However, challenges regarding muscle pressure loss and limited elongation potential have been identified. This paper presents a hyperelastic tubular Soft Composite that replicates the distinctive mechanical behaviour of the Pneumatic Artificial Muscle without the need for internal pressurization. The proposed Soft Composite solution is achieved by impregnating a prefabricated polyethylene terephthalate braided sleeve, held at a high initial fibre angle, with a silicone prepolymer. A comprehensive experimental evaluation is achieved on numerous prototypes for a variety of customizable design parameters including: the initial fibre angle, the silicone stiffness, and the braided sleeve style. This research has successfully developed, tested, and validated a novel Soft Composite that can achieve the desired nonlinear stiffness and elongation potential for optimal use as passive actuation in human mobility assistive devices.

Self-efficacy of physical education teachers in including students with cerebral palsy in their classes

Children with cerebral palsy (CP) are often mainstreamed into the general education system, but are likely to be excluded from physical education (PE) classes. A questionnaire was constructed and utilized to measure PE teachers’ self-efficacy (SE) toward inclusion of students with CP in each of three mobility categories (independent, using assistive devices, using wheelchair mobility) and the impact of experience and training on teachers’ SE. Participants in the study were 121 PE teachers from different parts of Israel (mean age: 41.02±9.33 years; range: 25.00–59.00 years). Exploratory factor analysis was used to determine the structure of the sub-scales’ factors’ structure and Cronbach’s Alpha reliability was satisfactory (range 0.872–0.941). Independent t-tests were calculated in order to compare the SE of teachers with and without adapted PE experience. Repeated Analysis of Variance was performed to measure within-group differences in SE. Results revealed that the PE teachers’ SE in teaching students who use mobility assistive devices or wheelchairs was significantly lower compared to teaching those who walk and run unaided (F=19.11; p<0.001). The teachers’ SE towards including CP children who independently ambulate was influenced (p<0.05; d=0.94) by the teacher’s experience (elementary school practicum). SE in the mobility with assistive device group was also significantly influenced (p<0.05; d=0.1) by teaching experience (previous experience and having a specialization in adapted PE). Finally, SE when teaching the wheelchair mobility group was influenced by having an adapted PE specialization (p<0.05; d=0.82). Specialized training in this particular area should be enhanced to increase teachers' SE and enable greater participation of children with CP in general physical education classes

Progressive disability in elderly population among tribals of Telangana: a cross sectional study

BackgroundThe tribal population of Telangana, India, lives in remote and difficult conditions. This study was carried out to find out estimate, the prevalence and progression of disability in elderly population among tribals of Khammam District, Telangana state, India.MethodsA population based cross sectional survey was conducted in villages of Tribal Sub Plan area. Elderly people who are 60 years or older were chosen with a two stage sampling procedure: (1) probability proportion to size was used to select clusters and (2) in each selected cluster households were selected by systematic random sampling. The participants were interviewed with the 36 item Telugu version of the World Health Organization Disability Assessment Schedule (WHODAS 2.0) questionnaire. Socio- demographic information, behavioral measurements, health and social benefit indicators were also assessed. Descriptive analytical methods were used for prevalence estimation and logistic regression was used to examine the associations of progressive age over disability among elderly.ResultsA total of 506 elderly people from 1349 households in 20 villages across 31mandals of Khammam were interviewed. Majority of elderly population among tribals were illiterate (men 88.94%; women 99.33%), used tobacco (men 81.25%; women 57.72%), consumed alcohol (men 80.77%; women 47.32%) and were hypertensive (men 53.85%; women 63.42%). The prevalence of disability was higher in women. Maximum disability in the interviewed elderly population was seen in domains of performing house hold activities, and mobility. In comparison with men, women expressed more disability for majority of domains. As age progressed, the disability for self-care domain increased to a maximum of 2.6 times in men and 6.6 times in women and for mobility domain increased to a maximum of 9.7 times in men and 7.2 times in women.ConclusionsAlthough present disability modifying mobility Assistive Devices (AD) can help elderly in overcoming disability, these are primarily designed for built environments. As the needs, cultural sensitivities, and living environment of elderly population in tribals are unique, newer innovative assistive devices should be designed and developed.

The use of a direct manufacturing prosthetic socket system in a rural community in South Africa: A pilot study and lessons for future research.

Challenges exist with the provision of appropriate mobility assistive devices in rural areas. The use of the direct manufacturing prosthetic socket system is a possible solution to these challenges. The objective of this study was to test and explore the clients' perspectives with the application of this device. Within a mixed-methods approach, a longitudinal sequential explanatory design was applied. The Orthotic and Prosthetic User's Survey was administered to explore the use of the direct manufacturing prosthetic socket system in terms of function, health-related quality of life and client satisfaction. A conveniently selected sample of 21 individuals who suffered a unilateral trans-tibial amputation was included. Data were collected at 1, 3 and 6 months post fitting, and two focus group discussions were also administered. Of the 21 participants recruited, 11 returned for follow up. Although participants reported favourably about the prosthesis, their scores were generally worse than the norms with regard to function and quality of life. Participants highlighted the need for improvement in the cosmetic appearance of the prosthesis. The direct manufacturing prosthetic socket system could be considered as an alternative technique of socket manufacturing for individuals living in rural areas due to the shorter manufacture time and promising initial results, but further research on this topic with a bigger sample is recommended. Clinical relevance The direct manufacturing prosthetic socket system may be considered as an alternative to the traditional prosthetic socket manufacturing technique used in South Africa. As this device requires only one visit and therefore decreased travel by the patients to the hospitals, it could be applicable to more amputees who cannot return to hospital post discharge.

Severity of motor dysfunction in children with cerebral palsy seen in Enugu, Nigeria.

IntroductionChildren with cerebral palsy (CP) have gross motor dysfunction (GMD) of varying degrees of severity. The Gross Motor Function Classification System (GMFCS) is widely used internationally to classify children with CP into functional severity levels. There are few reports on the use of GMFCS in Nigeria to determine the severity of motor dysfunction in children with CP. This study aims to classify children with CP in Enugu on the basis of severity of their GMD in order to ascertain their management needs.MethodsThe study was a cross sectional observational study and sample selection was by consecutive recruitment. One hundred (100) children with CP aged 9 – 96 months, attending two Pediatric Neurology Clinics in Enugu, were consecutively recruited. Relevant history was taken including modalities of treatment received. Neurological examination was done and the GMFCS manual was used to classify the children into levels of severity.ResultsGMD varied in severity in the patients from mild (47%) (GMFCS levels I & II) to moderate (7%) (GMFCS levels III) and to severe (46%) (GMFCS levels IV & V). Those in levels I – III (54%) were ambulatory while those in levels IV & V (46%) were non-ambulatory. Of the 53 that required mobility assistive device, only 6 (11.3%) were using one.ConclusionMore than half of CP patients seen in Enugu were ambulatory with mild to moderate motor dysfunction based on the GMFCS. Only a few of our patients are appropriately rehabilitated with augmentative interventions.

An Assistive Mobility Device for the Blind: White Guide

Presently, for making human life easier with innovative articles various approaches are being used. Blindness is a characteristic, not a disability or defect. Navigating in an unknown environment poses a great difficulty for the visually challenged people. They are dependent for any type of movement. To overcome this smart product is proposed that can be attached to white cane. White cane will help the user with obstacle detection, real time location tracking of the blind, support intimation in case of emergencies and some voice control features. It consists of various sensors to perceive the environment and give haptic feedbacks. The product connects with an Android application via Bluetooth. The main aim is to provide a reliable, safe, affordable and easy to use navigating tool to ease the lives of visually impaired people.

The extent of using mobility assistive devices can partly explain fatigue among persons with late effects of polio - a retrospective registry study in Sweden.

BackgroundFatigue is reported as one of the most disabling symptoms and is common among persons living with late effects of polio. Although fatigue has been studied in the context of people living with late effects of polio, there is a lack of knowledge concerning the association of fatigue and variables of importance for participation in daily life. Therefore, the aim of this study was to explore possible factors associated with fatigue among persons with late effects of polio in Sweden.MethodsThis retrospective registry study consisted of 89 persons with late effects of polio living in Sweden. Fatigue was measured with the Multidimensional Fatigue Inventory (MFI-20) scale, Swedish version. Pearson’s correlation coefficient was used to analyse the correlation between the factors and fatigue, and a multiple linear regression was carried out to explore factors for fatigue.ResultsFatigue statistically significantly correlated with age (r = 0.234, p < 0.05) and the use of mobility assistive devices (r = 0.255, p < 0.05). The multiple linear regression model showed that the factors age (β = 0.304, p < 0.019) and mobility assistive devices (β = 0.262, p < 0.017) were associated with fatigue among persons living with late effects of polio, and the model partly explained 14% of the variation of fatigue.ConclusionsFatigue could partly be explained by the extent of using mobility assistive devices and age. Healthcare professionals should provide and demonstrate the importance of assistive devices to ensure management of fatigue in persons living with late effects of polio.

Community reintegration and related factors in a Nigerian stroke sample.

The goal of stroke rehabilitation has shifted from mere survival of a victim to how well a survivor can be effectively reintegrated back into the community. The present study determined the level of satisfaction with community reintegration (CR) and related factors among Nigerian community-dwelling stroke survivors (CDSS). This was a cross-sectional survey of 71 volunteering CDSS (35 males, 36 females) from selected South-Eastern Nigerian communities. Reintegration to Normal Living Index was used to assess participants' CR. Data was analysed using Spearman rank-order correlation, Kruskal-Wallis and Mann-Whitney U tests at p≤0.05. Participants generally had deficits in CR which was either mild/moderate (52.1%) or severe (47.9%). Scores in the CR domains of distance mobility, performance of daily activities, recreational activities and family roles were particularly low (median scores ≤ 4). CR was significantly correlated with and influenced by age (r=-0.35; p=0.00) and presence/absence of diabetes mellitus (u=3.56.50; p=0.01), pre- (k=6.13; p=0.05) and post-stroke employment (k=18.26; p=0.00) status, type of assistive mobility device being used (AMD) (k=25.39; p=0.00) and support from the community (k=7.15; p=0.03) respectively. CR was generally poor for this CDSS sample. Survivors who are older, having diabetes as co-morbidity, using AMD (particularly wheel-chair) and without employment pre- and/or post-stroke may require keener attention. Rehabilitation focus may be targeted at enhancing mobility functions, vocational and social skills.

Ambulatory activity classification with dendogram-based support vector machine: Application in lower-limb active exoskeleton

Ambulatory activity classification is an active area of research for controlling and monitoring state initiation, termination, and transition in mobility assistive devices such as lower-limb exoskeletons. State transition of lower-limb exoskeletons reported thus far are achieved mostly through the use of manual switches or state machine-based logic. In this paper, we propose a postural activity classifier using a ‘dendogram-based support vector machine’ (DSVM) which can be used to control a lower-limb exoskeleton.A pressure sensor-based wearable insole and two six-axis inertial measurement units (IMU) have been used for recognising two static and seven dynamic postural activities: sit, stand, and sit-to-stand, stand-to-sit, level walk, fast walk, slope walk, stair ascent and stair descent. Most of the ambulatory activities are periodic in nature and have unique patterns of response. The proposed classification algorithm involves the recognition of activity patterns on the basis of the periodic shape of trajectories. Polynomial coefficients extracted from the hip angle trajectory and the centre-of-pressure (CoP) trajectory during an activity cycle are used as features to classify dynamic activities.The novelty of this paper lies in finding suitable instrumentation, developing post-processing techniques, and selecting shape-based features for ambulatory activity classification. The proposed activity classifier is used to identify the activity states of a lower-limb exoskeleton. The DSVM classifier algorithm achieved an overall classification accuracy of 95.2%.

Evaluation of a wrist orthosis on lofstrand crutch-assisted gait.

Lofstrand, or forearm, crutches are a common assistive mobility device for those with functional impairments. However, repeated loading of the wrist and palmar region and continual hyperextension of the wrist during Lofstrand crutch usage may cause wrist strain, pain, and secondary injuries such as carpal tunnel syndrome. In order to reduce risk of injury, a novel wrist orthosis was developed with the intent of improving wrist posture and reducing/redirecting palmar loads from the carpal tunnel region to the adductor pollicis area. Dominant-hand palmar loads and wrist extension angles of 10 healthy, able-bodied subjects were measured during swing-through Lofstrand crutch-assisted gait to demonstrate the orthosis effectiveness. Each subject performed 10 trials each with and without the orthosis. An enhanced understanding of the effects of the wrist orthosis on kinematics and palmar loading was gained through this study. Results indicated a significant decrease in maximum palmar force, contact area, and wrist extension when using the orthosis. Palmar loads were observed to be redirected toward the adductor pollicis when using an orthosis during Lofstrand crutch-assisted gait. Ultimately, this device was effective in redistributing palmar loads with the potential to reduce pain and risk of carpal tunnel syndrome in long-term Lofstrand crutch users.

Health-Promoting Physical Activity of Children Who Use Assistive Mobility Devices: A Scoping Review.

Children with physical disabilities who use assistive mobility devices (AMDs) are at risk for obesity and other secondary health conditions. Habitual physical activity is one lifestyle factor that may prevent obesity and contribute to overall health, and an active lifestyle in childhood improves prospects for lifelong healthy behaviors. Child, family, and environmental facilitators and barriers influence health-promoting physical activity (HPPA) for children without disabilities, but comparable models and levels of understanding for children who use AMDs are lacking. In this scoping review, we identified a similar set of child, family, and environmental facilitators and barriers relevant to HPPA participation among children who use AMDs. Noted gaps in the literature included limited reporting of AMD use, inconsistent HPPA definitions, and inadequate measurement tools for children who are nonambulatory. The identified child, family, and environmental factors provide a framework for occupational therapy practitioners and interprofessional teams to develop HPPA opportunities and interventions for an underserved population.

Burden of disease in adult patients with hypophosphatasia: Results from two patient-reported surveys

BackgroundHypophosphatasia (HPP) is a rare metabolic bone disease caused by loss-of-function mutation(s) in the tissue-nonspecific alkaline (TNSALP) phosphatase gene, which manifests as rickets and/or osteomalacia with systemic complications and affects patients of all ages. The burden of disease is poorly characterized in adult patients. AimsWe assessed patient-reported burden of disease using two surveys reasonably specific for HPP symptomatology, the Hypophosphatasia Impact Patient Survey (HIPS) and the Hypophosphatasia Outcomes Study Telephone interview (HOST). MethodsPatients with HPP were invited to participate via patient advocacy groups or their medical provider. Survey questions captured demography, HPP-related medical history, mobility, and health-related quality of life (using Short Form 12 [version 2] Health Survey [SF-12v2]) via internet report (HIPS) or telephone interview (HOST). ResultsOne hundred twenty-five adults responded (mean [standard deviation, SD] age: 45 [14.3] years). Eighty-four patients (67%) reported pediatric-onset of their symptoms. Common clinical features in the study population included pain (95% of patients), fractures (86% of patients) muscle weakness (62%) and unusual gait (52%). Use of assistive devices for mobility (60%) was also prevalent. Twenty-six percent of patients reported more than 10 fractures. Seventy-four percent of patients had undergone orthopedic/dental surgical procedures. The health profile of patients responding on the SF-12 showed a broad and substantial impact of HPP on health-related quality of life, with domains related to physical ability showing the greatest decrement compared to normative data. ConclusionsIn aggregate, these data indicate that HPP can confer a high burden of illness in adulthood.

Measuring the psychosocial impact of mobility assistive products with elderly people: Findings from Italian surveys

Purpose. In 2014 and 2015 the authors surveyed two samples of 79 and 65 users who had obtained mobility assistive devices from the National Health Service in Italy. The first sample was composed of powered wheelchair users, 71% of them being over 65 years old [1]. The second sample included users of seven different mobility assistive devices: powered wheelchairs, tilting manual wheelchairs, manual wheelchairs with seating system, tracked and wheeled stair-climbing devices, trans-femoral and trans-tibial lower limb prostheses); 42% of them were over 65 years old. Follow-up interviews were conducted in order to collect information about usage, effectiveness, usefulness and economic impact of their assistive device. Method. The instruments used in the interviews, which were conducted at the users’ homes, included an introductory questionnaire and other widely known assessment instruments, one of them being the PIADS (Psychosocial Impact of Assistive Devices Scale) [2], [3]. Results & Discussion. In both samples elderly people (those aged 65 or more) answered the PIADS items in greater numbers than those under 65. Some difficulties in answering the PIADS questions were noticed, which seem to be related to the kind of assistive device rather than to the age of the interviewed person. In the 2015 survey the number of subjects who did not answer the whole PIADS questionnaire was greater among users of assistive devices maneuvered by caregivers (tilting wheelchairs, manual wheelchairs with seating system, tracked and wheeled stair-climbing devices) than among users of devices providing full independence (powered wheelchairs, trans-femoral and trans-tibial lower limb prostheses). Another noteworthy finding is that, although all average scores obtained in the PIADS subscales were positive (about +1 in both samples), for elderly people the scores were a bit lower than those obtained from younger users. This does not occur for electronic wheelchairs users, whose scores don't differ in relation to the age of the interviewed subjects. Building on experience gained during these and previous studies, in the next two years a battery of outcome measurement instruments will be prepared to be used in clinical practice. References. 1. Salatino C, Andrich R, Converti RM, Saruggia M. An observational study of powered wheelchair pro-vision in Italy. Assistive technology 28(1) (2015) 41-52. 2. Andrich R, Pedroni F, Vanni G. Psychosocial Impact of Assistive Devices: Italian localization of the PIADS instrument. In: Craddock G et al (eds), Assistive technology: Shaping the future (AAATE 2003). Amsterdam: IOS Press (2003) 917–921. 3. Jutai J, Day H. Psychosocial Impact of Assistive Devices Scale (PIADS). Technology and Disability 14(3) (2002) 107–111.

The influence of a polymer damper on swing-through crutch gait biomechanics

Forearm crutch technology has evolved slowly compared to other assistive mobility devices, despite the highly repetitive nature of forearm crutch gait and the high incidence of overuse injuries. Using 13 able-bodied volunteers between the ages of 19 and 27, we compared the ground reaction forces of a novel crutch design featuring an elastomeric polymer situated below the handle to an identical design without a damper system and to a commercially available generic rigid forearm crutch model. There were no differences in peak vertical force or impulse between crutches. The crutch with the damper system demonstrated a significantly smaller peak braking force and impulse compared to the generic forearm crutch model. However, the crutch with the damper system demonstrated a significantly larger peak propulsive force and impulse compared to both crutch models. This finding indicates that a forearm crutch with a damper system may help to propel the crutch forward when walking on level surfaces, which could impact forward momentum.

Need and use of assistive devices for personal mobility by individuals with spinal cord injury

Objective: To investigate the provision, use, and unmet need of assistive devices for personal mobility in the Swiss population with spinal cord injury (SCI).Design: Community survey 2012 of the Swiss Spinal Cord Injury Cohort Study.Participants: Individuals aged 16 or older with traumatic or non-traumatic SCI residing in Switzerland.Interventions: Not applicable.Outcome Measures: Provision, frequency of use, and unmet need (i.e. perceiving the need of a device but it not being provided) of 11 mobility devices were assessed by self-report and analyzed descriptively. Provision of devices was further analyzed by sex, age, SCI etiology, SCI severity, and time since SCI.Results: Devices reported highest for provision (N = 492; mean age 55.3 ± 15.1 years; 28.9% female) were adapted cars (78.2%) and manual wheelchairs (69.9%). Provision of various devices markedly varied with age and SCI severity (e.g. 34.6% of those aged 76+ had a walking frame compared to 3.1% of those aged 31–45; 50.0% of participants with complete tetraplegia had a power wheelchair compared to 7.6% of those with complete paraplegia). Many devices were mostly used daily (e.g. manual wheelchair) while others were mostly used less frequently (e.g. handbikes). Unmet need was highest for arm braces (53.2% of those in need) and power assisted wheelchairs (47.3%), and lowest for crutches (11.4%) and manual wheelchairs (4.8%).Conclusion: The devices individuals have or use is largely dependent on their age and SCI severity. While most participants have access to basic mobility devices, there is still a considerable degree of unmet need for certain devices.

Slow Stream Rehabilitation: A New Model of Post-Acute Care

ObjectivesTo identify characteristics and outcomes of elderly patients admitted to a slow stream, low-intensity, and long-duration inpatient rehabilitation (SSR) program after an acute hospitalization because they were unable to tolerate traditional inpatient rehabilitation. DesignSingle group pre-post study with assessments conducted on admission and discharge. SettingBaycrest's 30-bed SSR Unit in Toronto, Ontario, Canada. ParticipantsA total of 104 patients older than 60 years admitted between September 2011 and December 2012. MeasurementsAdmission assessments included demographic data, Functional Independence Measure (FIM), and ability to ambulate. Discharge outcomes included change in motor and total FIM scores from admission to discharge, discharge residential status, and length of stay. ResultsMean age was 81.6 ± 8.4 years and 68.3% were women. Mean changes in motor and total FIM were 21.0 ± 12.2 (P < .001) and 22.6 ± 14.0 (P < .001), respectively. On admission, only 30.8% of patients were ambulatory even with mobility assistive devices, while on discharge, 68.3% of patients were ambulatory; 61.5% of patients returned to their preadmission living arrangement; 8.6% went from their own home to a retirement or relative's home. Only 16.3% were discharged to long-term nursing home care and 13.4% were transferred to an acute hospital. Mean length of SSR stay was 82.5 ± 26.4 days. ConclusionSSR programs can benefit elderly patients at risk for institutionalization after acute hospitalization by improving their functioning and mobility, and allowing them to return to the community.

The iPad as a mobile assistive technology device

Purpose – The purpose of this paper is to present the viewpoint of the authors on the use of the iPad as an assistive technology tool for post-secondary students with disabilities. Design/methodology/approach – Although this paper is not classified as a research article, the viewpoints discussed by the authors are related to a pilot study and continuing case study research they are conducting. Findings – The authors indicate that they have been surprised at the positive results they have observed in the iPad implementation, particularly with students moving to the iPad to continue their studies at the completion of the research. Practical implications – This paper discusses the opportunities and limitations afforded by the use of the iPad with post-secondary students as well as suggestions for implementation. Social implications – After decades of experience in the field of assistive technology, the authors are becoming convinced that the iPad offers significant opportunities for learning for students with disabilities. One of the exciting parts of being involved in these iPad studies has been to observe: the transformation of student study skills, the increased student self-discovery around how they learn, and the increase in student confidence in technology use. Perhaps rather than labeling the iPad as a mobile device or an assistive technology tool, the authors need to look at different terminology to define it. The ownership of this device by post-secondary students is growing every year, and it is a device that does not set students with disabilities apart from their peers. It is a device that can effectively support student learning through built in accessibility features and the use of commonly available and used apps. Perhaps using the term “equalizing technology” to describe the iPad might be more appropriate. Originality/value – This paper discusses the opportunities and limitations afforded by the use of the iPad with post-secondary students as well as suggestions for implementation. This is a rapidly developing area in universities and colleges around the world.

Basic Design of Visual Saliency Based Autopilot System Used for Omnidirectional Mobile Electric Wheelchair

This paper presents a fundamental design of an autopilot system to actualize automatic locomotion for an electric wheelchair with emphasis on simplicity and functionality. For this study, we designed a novel electric wheelchair with advanced mobility using Mecanum wheels that actualize omnidirectional movements without turning and developed a prototype with consideration devoted to the exterior design. Moreover, our developed prototype is considered with devotion of the exterior design. Our design concept is Electric Personal Assistive Mobility Device (EPAMD), which has ease of integration with a person's daily life. To prevent collisions, ranging sensors and depth sensors are used for environmental recognition. This paper presents global locomotion and local locomotion as frame- works for an autopilot. For global locomotion, we address algorithms of visual landmark detection based on visual saliency and the creation of category maps based on adaptive and unsupervised machine learning. Our method visualizes time-series features and their relations on visual landmarks in a low-dimensional space. We examine a novel design and its possible adaptation to an electric wheelchair as an EPAMD, especially intended to improve the independence of elderly people in their daily life.

Conception of Assistive Equipment for Rehabilitation of Patients with Spinal Cord Injury

Mobility is the urgent requisite of post spinal cord injury (SCI) patient. Since the alternative and compensatory approach is considered as the major function of mobility assistive device for post-SCI patients, the device should possess capability to acclimate to the ‘abnormal’ gait generate by the patients who usually undergo alternative and compensatory rehabilitation in their neural circuit. The functional ability of individual should be taking into account. Yet according to the requirement of neuro-protective treatment in post-SCI rehabilitation processing, locomotor-like activity is still an essential factor to patient. This study presents a novel concept and prototype of assistive technology base on foot control strategy to take an equilibrium between mobility and gait realization. To demonstrate that foot-induced over-ground locomotor assistive method is capable of achieving locomotor-like activity (dragging step), simulation analysis and prototype preliminary experiment have been conducted. Simulation analysis show that foot-induced assistance can allow more volitional activity compare to the hip-knee-induced assistive device. Yet the input and disturbance act on such kind of device may be increased. Surface electromyography (sEMG) from muscles of lower limb (right rectus femoris, right biceps femoris and right gluteus maximus) have been recorded during the preliminary experiment, and the mean of integrated EMG (iEMG) was used as evaluation of muscle activity. The result of the testing show that the mean of iEMG in the right gluteus maximus was reduced in the swing phase when the subject moving ahead with the prototype, but no significant change in the right rectus femoris. It may imply that foot-induced over-ground locomotor assistive device can reduce the muscle activity when patient complete locomotor-like movement and retain some amount of residual recruitment of lower limb, instead of substituting arbitrarily.