Nonlinear Dynamics of Upright Human Balance While Using a Passive-Cane

2016 ◽  
Author(s):  
James R. Chagdes ◽  
Joao P. Freire ◽  
Amit Shukla
Keyword(s):  
Nonlinear Dynamics ◽  
Mathematical Model ◽  
Assistive Technology ◽  
Treatment Plan ◽  
Assistive Technologies ◽  
Feedback Gain ◽  
Control Parameters ◽  
Human Posture ◽  
Inverted Pendulum Model ◽  
Potential Applications

Recent mathematical models of human posture have been explored to better understand the space of control parameters that result in stable upright balance. These models have demonstrated that there are two types of instabilities — a leaning instability and an instability leading to excessive oscillation. While these models provide insight into the stability of upright bipedal stance, they are not sufficient for individuals that require the aid of assistive technologies, such as a passive-cane or a walker. Without a valid model one is unable to understand the control parameters required for maintain upright posture or if similar instabilities even exist when assistive technologies are used. Therefore in this study, we developed a mathematical model of human posture while using a passive-cane to examine the nonlinear dynamics of stance. First, we developed a simple mathematical model of cane assisted human stance by adapting the inverted pendulum model of Chagdes et al., [1]. We modeled the human body, upper arm, forearm, cane, and ground as a two-degree-of-freedom, five-bar-linkage with pin joints representing the ankle, shoulder, elbow, and wrist joints. Second, we investigate upright stability in the parameter space of feedback gain and time-delay. We hypothesize that the analysis will show similar instabilities compared to that of a human standing without assistive technology. We also hypothesize that the space of control parameters which stabilize upright equilibrium posture will increase when a cane is incorporated. This study has two potential applications. First, the developed mathematical model could allow clinicians to better assess technology assisted balance and if needed help clinicians to customize a treatment plan for an individual that allows them to avoid unstable postural dynamics. Second, the mathematical model can be used to design customized assistive technology for people of difference physical properties and impairments.

Involving people with dementia and their informal caregivers in the development process of assistive technology: Description and evaluation of a user-centered design (Preprint)

2020 ◽  
Author(s):  
Iris A.G.M. Geerts ◽  
Liselore J.A.E Snaphaan ◽  
Inge M.B. Bongers
Keyword(s):  
Focus Groups ◽  
Assistive Technology ◽  
Field Study ◽  
Development Process ◽  
Technology Development ◽  
Informal Caregivers ◽  
Assistive Technologies ◽  
User Centered Design ◽  
People With Dementia ◽  
User Centered

BACKGROUND Despite the potential value of assistive technology to support people with dementia (PWD) in everyday activities, use of these technologies is still limited. To ensure that assistive technologies better address the specific needs and daily context of PWD and their informal caregivers, it is particularly important to involve them in all different phases of assistive technology development. The literature rarely describes the involvement of PWD throughout the development process of assistive technologies, which makes it difficult to further reflect on and improve active involvement of PWD. OBJECTIVE This two-part study aimed to gather insights on the user-centered design (UCD) applied in the development process of the alpha prototype of the serious game PLAYTIME by describing the methods and procedures of the UCD as well as evaluating the UCD from the perspective of all involved stakeholders. METHODS The first three phases of the user-driven Living Lab of Innovate Dementia 2.0 were applied to directly involve PWD and their informal caregivers through qualitative research methods, including focus groups and a context-field study, in the development of the alpha prototype of PLAYTIME from exploration to design to testing. After the testing phase, a total number of 18 semi-structured interviews were conducted with PWD, their informal caregivers and the project members of PLAYTIME to evaluate the applied UCD from the perspective of all involved stakeholders. The interviews addressed five of the principles for successful UCD and the appropriateness of the different methods used in the focus groups and context-field study. RESULTS Results of the interviews focused, amongst others, on the level of involvement of PWD and their informal caregivers in the development process, the input provided by PWD and their informal caregivers, the value of early prototyping, continuous iterations of design solutions and in-context testing, the role of dementia care professionals in the multidisciplinary project team, and the appropriateness of open- and closed-ended questions for obtaining input from PWD and their informal caregivers. CONCLUSIONS The description and evaluation of the UCD applied in the development process of the alpha prototype of PLAYTIME resulted in several insights on the relevance of UCD for all involved stakeholders as well as how PWD can be involved in the subsequent phases of usable and meaningful assistive technology development.

scholarly journals Normalizing Vision: The Representation and Use of Spectacles and Eyeglasses in Victorian Britain

2021 ◽  
Author(s):  
Gemma Almond
Keyword(s):  
Assistive Technology ◽  
Cultural Context ◽  
Assistive Technologies ◽  
The Body ◽  
Visual Aids ◽  
Medical Texts ◽  
Victorian Britain ◽  
Victorian Period ◽  
First Time ◽  
Material Evidence

Abstract This study explores the representation and use of Victorian visual aids, specifically focusing on how the design of spectacle and eyeglass frames shaped ideas of the ‘normal’ and ‘abnormal’ body. It contributes to our understanding of assistive technologies in the Victorian period by showcasing the usefulness of material evidence for exploring how an object was produced and perceived. By placing visual aids in their medical and cultural context for the first time, it will show how the study of spectacle and eyeglass frames develops our understanding of Victorian society more broadly. Contemporaries drew upon industrialization, increasing education, and the proliferation of print to explain a rise in refractive vision ‘errors’. Through exploring the design of three spectacle frames from the London Science Museum’s collections, this study will show how the representations and manufacture of visual aids transformed in response to these wider changes. The material evidence, as well as contemporary newspapers, periodicals, and medical texts, reveal that visual aids evolved from an unusual to a more mainstream device. It argues that visual aids are a unique assistive technology, one that is able to inform our understanding of how Victorians measured the body and constructed ideas of ‘normalcy’ and ‘abnormalcy’.

State Estimator of Flow as an Integrated Computational Method With the Feedback of Online Experimental Measurement

1997 ◽  
Vol 119 (4) ◽  
pp. 814-822 ◽  
Author(s):  
Toshiyuki Hayase ◽  
Satoru Hayashi
Keyword(s):  
Mathematical Model ◽  
Turbulent Flows ◽  
Experimental Measurement ◽  
Flow Simulation ◽  
Computational Method ◽  
Feedback Gain ◽  
State Estimator ◽  
Output Measurement ◽  
Real Flow ◽  
The Mathematical Model

This paper deals with a state estimator or simply an observer of flow field. The observer, being a fundamental concept in the control system theory, also has a potential in the analysis of flow related problems as an integrated computational method with the aid of experiment. In the framework of the observer, the state of physical flow is estimated from the mathematical model with the feedback of on-line experimental measurement. A SIMPLER based flow simulation algorithm is used as the mathematical model of the real flow and partial experimental measurement of flow is fed back to the boundary condition through the feedback controller. The existence of the feedback-loop essentially distinguishes the observer from ordinary flow simulations. Time variation of the computational result of the observer is expected to converge exactly to that of the physical flow in the whole flow domain even for unstable turbulent flows. A numerical experiment has been performed to confirm the validity of the proposed observer for a turbulent flow through a duct of square cross section. The physical flow to be estimated is modeled by a numerical solution. Appropriate choice for the proportional feedback gain of the observer results in accelerated convergence of the simulation by a factor of 0.012 and reduced error in estimation of the perturbation velocity by a factor of 0.6 in the whole domain or a factor of 0.3 behind the output measurement plane in comparison with the ordinary flow simulation without feedback.

scholarly journals Does assistive technology contribute to social inclusion for people with intellectual disability? A systematic review protocol

BMJ Open ◽  
2018 ◽  
Vol 8 (2) ◽  
pp. e017533 ◽  
Author(s):  
John Owuor ◽  
Fiona Larkan ◽  
Bonnix Kayabu ◽  
Geraldine Fitzgerald ◽  
Greg Sheaf ◽  
...  
Keyword(s):  
Intellectual Disability ◽  
Assistive Technology ◽  
Community Participation ◽  
Interpersonal Relationships ◽  
Social Inclusion ◽  
Research Programme ◽  
Study Groups ◽  
Assistive Technologies ◽  
Second Phase ◽  
Trinity College Dublin

IntroductionThe aim of this review is to answer the following question:Does assistive technology contribute to social inclusion for people with intellectual disability?Previous research on assistive technology has focused on socioeconomic impacts such as education, employment and access to healthcare by people with intellectual disability. There is a need to consolidate evidence on the interaction between intellectual disability, assistive technology, community living and social inclusion.Methods and analysisThe review will consider studies from all settings: geographical, socioeconomic and care (institutional and community care), published in English. Studies reported in other languages with abstracts in English will be included if they can be translated using Google Translate, otherwise such studies will be included in the appendix. The review will include both qualitative and quantitative studies. The intervention in this review refers to the use of assistive technology to promote community participation or interpersonal relationships (social inclusion) for people with intellectual disability. The outcomes will be behavioural and social benefits of using assistive technology by people with intellectual disability. Enhanced interpersonal relationships and community participation by people with intellectual disability. Data analysis will be in two phases. The first phase will involve analysis of individual study designs separately. The second phase will be narrative/thematic synthesis of all study groups.EthicsThe review will not create any ethical or safety concerns.DisseminationAt least one peer-reviewed article in a leading journal such as theBMJis planned. The findings will also be disseminated through a seminar session involving internal audience at Trinity College Dublin and within the Assistive Technologies for people with Intellectual Disability and Autism research programme.PROSPERO registration numberCRD42017065447; Pre-results.

A Mechanical Filter Concept to Suppress Crane Load Oscillations

1997 ◽  
Author(s):  
B. Balachandran ◽  
Y.-Y. Li
Keyword(s):  
Nonlinear Dynamics ◽  
Dynamical Systems ◽  
Control Parameters ◽  
Pivot Point ◽  
Preliminary Results ◽  
Scalar Control ◽  
Load Response ◽  
Mechanical Filter ◽  
Circular Track ◽  
Ship Roll

Abstract In this article, preliminary results obtained in the exploration of a mechanical filter concept for suppressing crane-load oscillations on a ship vessel are presented. The pivot point about which the load oscillates is constrained to follow a circular track in the considered filter. The governing dynamical systems for the cases with and without the filter are presented, and the nonlinear dynamics of these systems is studied with respect to quasi-static variation of different scalar control parameters. It is shown that the presence of the filter helps in eliminating some of the sub-critical bifurcations that may arise in the crane-load response during periodic ship-roll excitations.

Nonlinear Dynamics of the Bombardier Beetle

1999 ◽  
Author(s):  
Richard H. Rand ◽  
Erika T. Wirkus ◽  
J. Robert Cooke
Keyword(s):  
Nonlinear Dynamics ◽  
Mathematical Model ◽  
Differential Equations ◽  
Equilibrium Point ◽  
Defense Mechanism ◽  
Fluid Pressure ◽  
Pulsed Jet ◽  
Dependent Variables

Abstract This work investigates the dynamics by which the bombardier beetle releases a pulsed jet of fluid as a defense mechanism. A mathematical model is proposed which takes the form of a pair of piece wise continuous differential equations with dependent variables as fluid pressure and quantity of reactant. The model is shown to exhibit an effective equilibrium point (EEP). Conditions for the existence, classification and stability of an EEP are derived and these are applied to the model of the bombardier beetle.

Human Performance

2014 ◽  
pp. 267-273
Keyword(s):  
Assistive Technology ◽  
Human Performance ◽  
People With Disabilities ◽  
Critical Factor ◽  
Assistive Technologies ◽  
Working Environments ◽  
The Future ◽  
Performance Issues ◽  
The One ◽  
The Impact

This chapter looks into horizontal issues in ICT advances and discusses how the factor of human performance could help in increasing the impact of eAccessibility and assistive technologies in the future. More specifically, it revisits some of the ideas presented in earlier chapters looking at them from a different angle. The one of maximizing the audience and target group for assistive technologies through the increase in human performance, issues related with exoskeletons for working environments and dual use of assistive technology, sports as a motivator, aesthetics and fashion of prosthetics are discussed from this same perspective. Human performance could be a critical factor for the future of assistive technologies, and today's people with disabilities could become tomorrow's people with super-abilities and leaders in human performance issues.

Effects of Assistive Technologies Combined with Desktop Virtual Reality in Instructional Procedures (1)

2010 ◽  
pp. 299-305
Author(s):  
Gary Dotterer
Keyword(s):  
Virtual Reality ◽  
Assistive Technology ◽  
Learning Process ◽  
Assistive Technologies ◽  
Advanced Technology ◽  
Traditional Methods ◽  
Web Based ◽  
Desktop Virtual Reality ◽  
Instructional Procedures ◽  
Learning Performances

Based on research, desktop virtual reality (DVR) has been shown to have learning benefits over traditional methods of instruction. However, implementing assistive technology (ATs) in DVR would seem to enhance the learning process. This study aimed to examine effects of web-based DVR on learning performances. The literature reviewed for this particular study ultimately shows DVR to be beneficial in training in many fields found in the workforce. The overall advantages utilizing advanced technology in the form of DVR and ATs allow safe and controlled training environments, realistic simulations, and the ability to reconstruct learner processes and interactions.

Investigating Assistive Technologies using Computers to Simulate Basic Curriculum for Individuals with Cognitive Impairments

2010 ◽  
pp. 61-75 ◽  
Author(s):  
Carolyn Kinsell
Keyword(s):  
Assistive Technology ◽  
Transfer Of Learning ◽  
Cognitive Impairments ◽  
Assistive Technologies ◽  
Cognitively Impaired ◽  
Traditional Classrooms ◽  
Active Participant ◽  
Knowledge And Skills ◽  
Computer Based ◽  
Theoretical Foundations

Providing assistive technologies to cognitively impaired students, in the form of computer-based simulations, may improve the transfer of learning at a greater rate than other training media. The underlying premise for using computer-based simulations is that the cognitively impaired student is no longer the passive learner normally found in traditional classrooms. Instead, the cognitively impaired student becomes an active participant with the simulation and learning. In addition, this type of assistive technology provides the student with an opportunity for repeated exposure and practice at a speed in which the student feels comfortable. This chapter discusses the benefits of using computer-based simulations, defines the theoretical foundations that support the transfer of learning, and presents the processes that facilitate individual acquisition and refinement of knowledge and skills. It concludes with a review of the cognitive elements in the creation of mental models and schema.

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