Integration of Assistive Technologies into 3D Simulations: Exploratory Studies

Virtual worlds and environments have many purposes, ranging from games to scientific research. However, universal accessibility features in such virtual environments are limited. As the impairment prevalence rate increases yearly, so does the research interests in the field of assistive technologies. This work introduces research in assistive technologies and presents three software developments that explore the integration of assistive technologies within virtual environments, with a strong focus on Brain-Computer Interfaces. An accessible gaming system, a hands-free navigation software system, and a Brain-Computer Interaction plugin have been developed to study the capabilities of accessibility features within virtual 3D environments. Details of the specification, design, and implementation of these software applications are presented in the thesis. Observations and preliminary results as well as directions of future work are also included

Assisted Interaction for Improving Web Accessibility: An Approach Driven and Tested by Userswith Disabilities

148 p.Un porcentaje cada vez mayor de la población mundial depende de la Web para trabajar, socializar, opara informarse entre otras muchas actividades. Los beneficios de la Web son todavía más cruciales paralas personas con discapacidades ya que les permite realizar un sinfín de tareas que en el mundo físico lesestán restringidas debido distintas barreras de accesibilidad. A pesar de sus ventajas, la mayoría depáginas web suelen ignoran las necesidades especiales de las personas con discapacidad, e incluyen undiseño único para todos los usuarios. Existen diversos métodos para combatir este problema, como porejemplo los sistemas de ¿transcoding¿, que transforman automáticamente páginas web inaccesibles enaccesibles. Para mejorar la accesibilidad web a grupos específicos de personas, estos métodos requiereninformación sobre las técnicas de adaptación más adecuadas que deben aplicarse.En esta tesis se han realizado una serie de estudios sobre la idoneidad de diversas técnicas de adaptaciónpara mejorar la navegación web para dos grupos diferentes de personas con discapacidad: personas conmovilidad reducida en miembros superiores y personas con baja visión. Basado en revisionesbibliográficas y estudios observacionales, se han desarrollado diferentes adaptaciones de interfaces web ytécnicas alternativas de interacción, que posteriormente han sido evaluadas a lo largo de varios estudioscon usuarios con necesidades especiales. Mediante análisis cualitativos y cuantitativos del rendimiento yla satisfacción de los participantes, se han evaluado diversas adaptaciones de interfaz y métodosalternativos de interacción. Los resultados han demostrado que las técnicas probadas mejoran el acceso ala Web y que los beneficios varían según la tecnología asistiva usada para acceder al ordenador

Longitudinal Study of Two Virtual Cursors for People With Motor Impairments: A Performance and Satisfaction Analysis on Web Navigation

The lack of dexterity in the upper limbs of people with motor impairments may prevent the use of standard pointing devices, such as mice, to access graphical user interfaces. In these cases, pointing and clicking are usually performed by means of alternative devices such as joysticks, trackballs or standard keyboards. However, target acquisition can still be challenging for this group of people due to their physical condition. Based on previous works, we developed two virtual cursors: the novel cross cursor and the standard area cursor. They are devoted to assist two different groups of users with link selection within web pages: keyboard-only users, and joystick and trackball users, respectively. Both virtual cursors have been evaluated and compared with the original unassisted cursor in a longitudinal study. Eight people with motor impairments participated in an unsupervised experiment from their own personal computers at home. For a period of six weeks, each participant used both a virtual cursor and the original unassisted cursor to freely navigate the Web, and to perform predefined target acquisition tasks. Interaction data was automatically logged throughout the study along with subjective assessments concerning the usability of the virtual cursor being tested. Results show significant improvements for both virtual cursors in six of the seven cursor parameters studied, albeit with performance variations between some participants. The virtual cursors were extensively used for free web navigation and in their subjective assessments both were positively endorsed by participants who also put forward improvement suggestions for future developments

Intelligent Interfaces to Empower People with Disabilities

Severe motion impairments can result from non-progressive disorders, such as cerebral palsy, or degenerative neurological diseases, such as Amyotrophic Lateral Sclerosis (ALS), Multiple Sclerosis (MS), or muscular dystrophy (MD). They can be due to traumatic brain injuries, for example, due to a traffic accident, or to brainste

Advanced Augmentative and Alternative Communication System Based in Physiological Control

Dyskinetic Cerebral Palsy (DCP) is mainly characterized by alterations in muscle tone and involuntary movements. Therefore, these people present with difficulties in coordination and movement control, which makes walking difficult and affects their posture when seated. Additionally, their cognitive performance varies between being completely normal and severe mental retardation. People with DCP were selected as the objective of this thesis due to their multiple and complex limitations (speech problems and motor control) and because their capabilities have a great margin for improvement thanks to physiological control systems. Given their communication difficulties, some people with DCP have good motor con-trol and can communicate with written language. However, most have difficulty using Augmentative and Alternative Communication (AAC) systems. People with DCP gen-erally use concept boards to indicate the idea they want to communicate. However, most communication solutions available today are based on proprietary software that makes it difficult to customize the concept board and this type of control system. This is the motivation behind this thesis, with the aim of creating an interface with characteristics, able to be adapted to the user needs and limitations. Thus, this thesis proposes an Augmentative and Alternative Communication System for people with DCP based on physiological control. In addition, an innovative system for direct con-trol of concept boards with EMG is proposed. This control system is based on a physi-cal model that reproduces the muscular mechanical response (stiffness, inertia and viscosity). It allows for a selection of elements thanks to small pulses of EMG signal with sensors on a muscle with motor control. Its main advantage is the possibility of correcting errors during selection associated with uncontrolled muscle impulses, avoid-ing sustained muscle effort and thus reduced fatigue.La Parálisis Cerebral de tipo Discinésica (DCP) se caracteriza principalmente por las alteraciones del tono muscular y los movimientos involuntarios. Por ello, estos pacientes presentan dificultades en la coordinación y en el control de movimientos, lo cual les dificulta el caminar y afecta su postura cuando están sentados. Cabe resaltar que la capacidad cognitiva de las personas con DCP puede variar desde completamente normal, hasta un retraso mental severo. Las personas con DCP han sido seleccionadas como objetivo de esta tesis ya el margen de mejora de sus capacidades es amplio gracias a sistemas de control fisiológico, debido a sus múltiples y complejas limitaciones (problemas de habla y control motor). Debido a sus dificultades de comunicación, algunas personas con DCP se pueden comunicar con lenguaje escrito, siempre y cuando tenga un buen control motor. Sin embargo, la mayoría tienen dificultades para usar sistemas de Comunicación Aumentativos y Alternativos (AAC). De hecho, las personas con DCP utilizan generalmente tableros de conceptos para indicar la idea que quieren transmitir. Sin embargo, la mayoría las soluciones de comunicación disponibles en la actualidad están basadas en software propietario que hacen difícil la personalización del tablero de conceptos y el tipo de sistema de control. Es aquí donde surge esta tesis, con el objetivo de crear una interfaz con esas características, capaz de adaptarse a las necesidades y limitaciones del usuario. De esta forma, esta tesis propone un sistema de comunicación aumentativo y alternativo para personas con DCP basado en control fisiológico. Además, se propone un Sistema innovador de control directo sobre tableros de conceptos basado en EMG. Este Sistema de control se basa en un modelo físico que reproduce la respuesta mecánica muscular (basado en parámetros como Rigidez, Inercia y Viscosidad), permitiendo la selección de elementos gracias a pequeños pulsos de señal EMG con sensores sobre un músculo con control motor. Sus principales ventajas son la posibilidad de corregir errores durante la selección asociado a los impulsos musculares no controlados, evitar el esfuerzo muscular mantenido para alcanzar un nivel y reducir la fatiga.La Paràlisi Cerebral de tipus Discinèsica (DCP) es caracteritza principalment per les alteracions del to muscular i els moviments involuntaris. Per açò, aquests pacients presenten dificultats en la coordinació i en el control de moviments, la qual cosa els dificulta el caminar i afecta la seua postura quan estan asseguts. Cal ressaltar que la capacitat cognitiva de les persones amb DCP pot variar des de completament normal, fins a un retard mental sever. Les persones amb DCP han sigut seleccionades com a objectiu d'aquesta tesi ja el marge de millora de les seues capacitats és ampli gràcies a sistemes de control fisiològic, a causa dels seus múltiples i complexes limitacions (problemes de parla i control motor). A causa de les seues dificultats de comunicació, algunes persones amb DCP es poden comunicar amb llenguatge escrit, sempre que tinga un bon control motor. No obstant açò, la majoria tenen dificultats per a usar sistemes de Comunicació Augmentatius i Alternatius (AAC). De fet, les persones amb DCP utilitzen generalment taulers de conceptes per a indicar la idea que volen transmetre. No obstant açò, la majoria les solucions de comunicació disponibles en l'actualitat estan basades en programari propietari que fan difícil la personalització del tauler de conceptes i el tipus de sistema de control. És ací on sorgeix aquesta tesi, amb l'objectiu de crear una interfície amb aqueixes característiques, capaç d'adaptar-se a les necessitats i limitacions de l'usuari. D'aquesta forma, aquesta tesi proposa un sistema de comunicació augmentatiu i alternatiu per a persones amb DCP basat en control fisiològic. A més, es proposa un sistema innovador de control directe sobre taulers de conceptes basat en EMG. Aquest sistema de control es basa en un model físic que reprodueix la resposta mecànica muscular (basat en paràmetres com a Rigidesa, Inèrcia i Viscositat), permetent la selecció d'elements gràcies a xicotets polsos de senyal EMG amb sensors sobre un múscul amb control motor. Els seus principals avantatges són la possibilitat de corregir errors durant la selecció associat als impulsos musculars no controlats, evitar l'esforç muscular mantingut per a aconseguir un nivell i reduir la fatiga.Díaz Pineda, JA. (2017). Advanced Augmentative and Alternative Communication System Based in Physiological Control [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/90418TESI

ACCESSIBILITY IN CONTEXT: UNDERSTANDING THE TRULY MOBILE EXPERIENCE OF USERS WITH MOTOR IMPAIRMENTS

Touchscreen smartphones are becoming broadly adopted by the US population. Ensuring that these devices are accessible for people with disabilities is critical for equal access. For people with motor impairments, the vast majority of studies on touchscreen mobile accessibility have taken place in the laboratory. These studies show that while touchscreen input offers advantages, such as requiring less strength than physical buttons, it also presents accessibility challenges, such as the difficulty of tapping on small targets or making multitouch gestures. However, because of the focus on controlled lab settings, past work does not provide an understanding of contextual factors that impact smartphone use in everyday life, and the activities these devices enable for people with motor impairments. To investigate these issues, this thesis research includes two studies, first, an in-person study with four participants with motor impairments that included diary entries and an observational session, and, secondarily, an online survey with nine respondents. Using case study analysis for the in-person participants, we found that mobile devices have the potential to help motor-impaired users reduce the physical effort required for everyday tasks (e.g., turning on a TV, checking transit accessibility in advance), that challenges in touchscreen input still exist, and that the impact of situational impairments to this population can be impeding. The online survey results confirm these findings, for example, highlighting the difficulty of text input, particularly when users are out and mobile rather than at home. Based on these findings, future research should focus on the enhancement of current touchscreen input, exploring the potential of wearable devices for mobile accessibility, and designing more applications and services to improve access to physical world

Collaborative adaptive accessibility and human capabilities

This thesis discusses the challenges and opportunities facing the field of accessibility, particularly as computing becomes ubiquitous. It is argued that a new approach is needed that centres around adaptations (specific, atomic changes) to user interfaces and content in order to improve their accessibility for a wider range of people than targeted by present Assistive Technologies (ATs). Further, the approach must take into consideration the capabilities of people at the human level and facilitate collaboration, in planned and ad-hoc environments. There are two main areas of focus: (1) helping people experiencing minor-to-moderate, transient and potentially-overlapping impairments, as may be brought about by the ageing process and (2) supporting collaboration between people by reasoning about the consequences, from different users perspectives, of the adaptations they may require. A theoretical basis for describing these problems and a reasoning process for the semi-automatic application of adaptations is developed. Impairments caused by the environment in which a device is being used are considered. Adaptations are drawn from other research and industry artefacts. Mechanical testing is carried out on key areas of the reasoning process, demonstrating fitness for purpose. Several fundamental techniques to extend the reasoning process in order to take temporal factors (such as fluctuating user and device capabilities) into account are broadly described. These are proposed to be feasible, though inherently bring compromises (which are defined) in interaction stability and the needs of different actors (user, device, target level of accessibility). This technical work forms the basis of the contribution of one work-package of the Sustaining ICT use to promote autonomy (Sus-IT) project, under the New Dynamics of Ageing (NDA) programme of research in the UK. Test designs for larger-scale assessment of the system with real-world participants are given. The wider Sus-IT project provides social motivations and informed design decisions for this work and is carrying out longitudinal acceptance testing of the processes developed here

Augmenting User Interfaces with Haptic Feedback

Computer assistive technologies have developed considerably over the past decades. Advances in computer software and hardware have provided motion-impaired operators with much greater access to computer interfaces. For people with motion impairments, the main di�culty in the communication process is the input of data into the system. For example, the use of a mouse or a keyboard demands a high level of dexterity and accuracy. Traditional input devices are designed for able-bodied users and often do not meet the needs of someone with disabilities. As the key feature of most graphical user interfaces (GUIs) is to point-and-click with a cursor this can make a computer inaccessible for many people. Human-computer interaction (HCI) is an important area of research that aims to improve communication between humans and machines. Previous studies have identi�ed haptics as a useful method for improving computer access. However, traditional haptic techniques su�er from a number of shortcomings that have hindered their inclusion with real world software. The focus of this thesis is to develop haptic rendering algorithms that will permit motion-impaired operators to use haptic assistance with existing graphical user interfaces. The main goal is to improve interaction by reducing error rates and improving targeting times. A number of novel haptic assistive techniques are presented that utilise the three degrees-of-freedom (3DOF) capabilities of modern haptic devices to produce assistance that is designed speci�- cally for motion-impaired computer users. To evaluate the e�ectiveness of the new techniques a series of point-and-click experiments were undertaken in parallel with cursor analysis to compare the levels of performance. The task required the operator to produce a prede�ned sentence on the densely populated Windows on-screen keyboard (OSK). The results of the study prove that higher performance levels can be i ii achieved using techniques that are less constricting than traditional assistance