Biomechanics

Biomechanics is a vast discipline within the field of Biomedical Engineering. It explores the underlying mechanics of how biological and physiological systems move. It encompasses important clinical applications to address questions related to medicine using engineering mechanics principles. Biomechanics includes interdisciplinary concepts from engineers, physicians, therapists, biologists, physicists, and mathematicians. Through their collaborative efforts, biomechanics research is ever changing and expanding, explaining new mechanisms and principles for dynamic human systems. Biomechanics is used to describe how the human body moves, walks, and breathes, in addition to how it responds to injury and rehabilitation. Advanced biomechanical modeling methods, such as inverse dynamics, finite element analysis, and musculoskeletal modeling are used to simulate and investigate human situations in regard to movement and injury. Biomechanical technologies are progressing to answer contemporary medical questions. The future of biomechanics is dependent on interdisciplinary research efforts and the education of tomorrow’s scientists

Advanced Low-Floor Vehicle (ALFV) Specification Research

This report details the results of research on market comparison, operational cost efficiencies, and prototype tests conducted on a novel design for an Advanced Low Floor Vehicle (ALFV), flex-route transit bus. Section I describes how the need for such a bus arises from a combination of diminishing transit funding from the federal government and demographic and transportation factors. Section II describes the unique features of this bus design that render it suitable for rural and urban operation, including improved transit passenger and wheelchair accessibility, reduced maintenance, structural design features, safety provisions, and the technical specifications of this design. Section III details the potential differences in capital and operational costs of procuring and operating this bus in a fleet. Potential cost reductions due to the long-life vehicle concept, maneuverability, operational savings (from APTA Bus Roadeo tests), and reserve fleet savings are explored. Section IV refers to the Federal Transit Administration (FTA) new model bus tests (“Altoona Testing”). However, at the this time, the Altoona Bus Test Report for these tests is not yet released by the bus manufacturer, Ride Solution, Inc., as is its right under the Bus Testing Regulation. The report must be released to the public before this bus can be purchased by a transit agency using FTA funds. In addition to the standard Altoona Bus Test, additional research was conducted to determine the turning ability, suspension travel, ramp travel index, field of view for the driver, compliance to Americans with Disabilities Act (ADA) requirements, and timed assessment of wheelchair securement. Section IV also presents the results of these tests. Section V presents results from a market comparison that included the buses in this mid-size category that were tested at Altoona and are expected to be available for FTA grantees to purchase. The specifications and performance of the ALFV bus are compared with these buses. Section VI presents a flex-route utilization plan, and Section VII provides the results from a survey of transit professionals about their interest in the features of this bus design. Section VIII gives Ride Solution’s experience in developing the concept for ALFV. Conclusions of this report are presented in Section IX, followed by the references and appendices

Neuroergonomic Assessment of Wheelchair Control Using Mobile fNIRS

For over two centuries, the wheelchair has been one of the most common assistive devices for individuals with locomotor impairments without many modifications. Wheelchair control is a complex motor task that increases both the physical and cognitive workload. New wheelchair interfaces, including Power Assisted devices, can further augment users by reducing the required physical effort, however little is known on the mental effort implications. In this study, we adopted a neuroergonomic approach utilizing mobile and wireless functional near infrared spectroscopy (fNIRS) based brain monitoring of physically active participants. 48 volunteers (30 novice and 18 experienced) self-propelled on a wheelchair with and without a PowerAssist interface in both simple and complex realistic environments. Results indicated that as expected, the complex more difficult environment led to lower task performance complemented by higher prefrontal cortex activity compared to the simple environment. The use of the PowerAssist feature had significantly lower brain activation compared to traditional manual control only for novices. Expertise led to a lower brain activation pattern within the middle frontal gyrus, complemented by performance metrics that involve lower cognitive workload. Results here confirm the potential of the Neuroergonomic approach and that direct neural activity measures can complement and enhance task performance metrics. We conclude that the cognitive workload benefits of PowerAssist are more directed to new users and difficult settings. The approach demonstrated here can be utilized in future studies to enable greater personalization and understanding of mobility interfaces within real-world dynamic environments

The overlooked outcome measure for spinal cord injury: use of assistive devices

Although several outcome measures are used to assess various areas of interest regarding spinal cord injuries (SCIs), little is known about the frequency of their use, and the ways in which they transform shared knowledge into implemented practices. Herein, 800 professionals from the International Spinal Cord Society, especially trained for caring in patients with SCI, were invited to respond to an Internet survey collecting information on the use of standardized measures in daily clinical practices. We asked both clinicians and researchers with different areas of interest about their use of functional outcome measures, and, in particular, which scales they habitually use to assess various aspects of clinical practice and rehabilitation. We selected a set of rating scales, which were validated for measuring SCIs (http://www.scireproject.com/outcome-measures). The results show that the areas of interest assessed by most of the participants were neurological status, upper limb, lower limb gait, pain, spasticity, self-care, and daily living. The most widely used rating scales were the spinal cord independence measure, the functional independence measure and the International Standards for Neurological Classification of Spinal Cord Injury. Instead, the majority of respondents did not evaluate the use of assistive technology. Despite the availability of several outcome scales, the practice of evaluating SCIs with standardized measures for assistive technologies and wheelchair mobility is still not widespread, even though it is a high priority in the rehabilitation of SCI patients. The results emphasize the need for a more thorough knowledge and use of outcome scales, thus improving the quality of assistive device evaluation

How a Diverse Research Ecosystem Has Generated New Rehabilitation Technologies: Review of NIDILRR’s Rehabilitation Engineering Research Centers

Over 50 million United States citizens (1 in 6 people in the US) have a developmental, acquired, or degenerative disability. The average US citizen can expect to live 20% of his or her life with a disability. Rehabilitation technologies play a major role in improving the quality of life for people with a disability, yet widespread and highly challenging needs remain. Within the US, a major effort aimed at the creation and evaluation of rehabilitation technology has been the Rehabilitation Engineering Research Centers (RERCs) sponsored by the National Institute on Disability, Independent Living, and Rehabilitation Research. As envisioned at their conception by a panel of the National Academy of Science in 1970, these centers were intended to take a “total approach to rehabilitation”, combining medicine, engineering, and related science, to improve the quality of life of individuals with a disability. Here, we review the scope, achievements, and ongoing projects of an unbiased sample of 19 currently active or recently terminated RERCs. Specifically, for each center, we briefly explain the needs it targets, summarize key historical advances, identify emerging innovations, and consider future directions. Our assessment from this review is that the RERC program indeed involves a multidisciplinary approach, with 36 professional fields involved, although 70% of research and development staff are in engineering fields, 23% in clinical fields, and only 7% in basic science fields; significantly, 11% of the professional staff have a disability related to their research. We observe that the RERC program has substantially diversified the scope of its work since the 1970’s, addressing more types of disabilities using more technologies, and, in particular, often now focusing on information technologies. RERC work also now often views users as integrated into an interdependent society through technologies that both people with and without disabilities co-use (such as the internet, wireless communication, and architecture). In addition, RERC research has evolved to view users as able at improving outcomes through learning, exercise, and plasticity (rather than being static), which can be optimally timed. We provide examples of rehabilitation technology innovation produced by the RERCs that illustrate this increasingly diversifying scope and evolving perspective. We conclude by discussing growth opportunities and possible future directions of the RERC program

THE IMPACT OF A PUSHRIM ACTIVATED POWER ASSIST WHEELCHAIR AMONG INDIVIDUALS WITH TETRAPLEGIA

The goal of this project was to test the influence of a pushrim activated power-assisted wheelchair (PAPAW) on the functional capabilities of individuals with cervical level spinal cord injuries (tetraplegia). This repeated measures design type study was divided into two phases, which included testing in two different laboratory settings: a biomechanics laboratory and an activities of daily living laboratory. Fifteen participants included in both phases were fulltime manual wheelchair users (MWUs) with tetraplegia. The purpose of the first phase of the study was to determine the differences in metabolic demands, stroke frequency, and upper extremity joint range of motion, during PAPAW propulsion and traditional manual wheelchair propulsion. Participants propelled both their own manual wheelchairs and a PAPAW through three different resistances (slight, moderate and high), on a computer controlled wheelchair dynamometer. Variables analyzed during this phase included: mean steady state oxygen consumption, ventilation, heart rate, mean stroke frequency, maximum upper extremity joint range of motion, and propulsion speed. Results from the first phase of the study revealed a significant improvement in kinematic, speed, and metabolic variables when participants were propelling with a PAPAW. In Phase II, participants propelled both their own manual wheelchairs and a PAPAW three times over an activities of daily living course. The course was constructed to reflect certain obstacles that a manual wheelchair user might encounter in his or her daily routine. PAPAWs received higher user ratings than the participant's own manual wheelchair for 10 out of 18 obstacles. Additionally, when using a PAPAW, participants were able to complete the course in the same amount of time while maintaining a lower mean heart rate. For individuals with tetraplegia, PAPAWs have the potential to decrease metabolic demands during propulsion, while increasing or maintaining function within ADLs. Use of this device could help MWUs maintain overall physical capacity while reducing the risk for pain and injuries to the upper extremities, which are often seen among manual wheelchair users with tetraplegia. Future studies with this device should focus on the ability of MWUs with tetraplegia to perform necessary activities of daily living within their home environment and community

Overcoming barriers and increasing independence: service robots for elderly and disabled people

This paper discusses the potential for service robots to overcome barriers and increase independence of elderly and disabled people. It includes a brief overview of the existing uses of service robots by disabled and elderly people and advances in technology which will make new uses possible and provides suggestions for some of these new applications. The paper also considers the design and other conditions to be met for user acceptance. It also discusses the complementarity of assistive service robots and personal assistance and considers the types of applications and users for which service robots are and are not suitable

Practice-based skill acquisition of pushrim-activated power-assisted wheelchair propulsion versus regular handrim propulsion in novices

BACKGROUND: Regular handrim wheelchair (RHW) propulsion is straining for the upper extremities and wheelchair users often experience overuse problems. A recent advancement in wheelchair technology that could assist users is the pushrim-activated power-assisted wheelchair (PAPAW). PAPAWs are challenging to control, yet it is unclear how people learn to use a PAPAW. The purpose of this study is to examine early skill acquisition through practice in PAPAWs and compare it with RHWs. METHODS: Twenty-four able-bodied novices were randomly allocated to either the RHW group or the PAPAW group. The experiment consisted of five sessions with three blocks of 4 min steady-state practice at 1.11 m/s and 0.21 W/kg. Finally, a transfer to the other mode was made. Data were collected with a drag-test, breath-by-breath spirometry, and a motion capture system. The last minute of each four-minute block was used for analysis. A mixed analysis of variance (ANOVA) was used to test for group, time, and interaction effects. RESULTS: Both groups improved their (assisted) mechanical efficiency, reduced their stroke rate, right-left and forward-backward deviation on the treadmill, and had a lower rate of perceived exertion (RPE) over time. (Assisted) mechanical efficiency was higher for the PAPAW group than for the RHW group and RPE was lower. However, left-right and forward-backward deviation was also found to be higher in the PAPAW group. CONCLUSIONS: At the group level the energetic cost of RHW and PAPAW propulsion can be lowered through low-intensity practice in novice users. The PAPAW is more 'efficient' than the RHW given the reduced energy requirement of the user from the motor assist, but more difficult to control. Future studies on PAPAWs should focus on the control needs of the user and their interaction with the power-assist technology