Access technologies facilitate novel and alternative methods for individuals with disabilities to interact with their environment. Finding suitable access solutions for children with severe spastic quadriplegic cerebral palsy can be difficult because of their poor motor control and targeting abilities due to spasticity at the limbs, neck, and head. In this research a multiple camera tongue switch was developed for a 7 year-old case study participant with severe spastic quadriplegia. Remotely via video, this system reacts to tongue protrusions as cues for single-switch access. Having multiple cameras mitigates targeting problems with the head that conventional single camera systems would present. Results of a usability experiment with the participant show that good sensitivity (82%) and specificity (80%) can be achieved with a non-contact tongue protrusion access modality for a user with spastic quadriplegia. Moreover, the experiment verified that the extra cameras improve utility of video-based access technologies for the target population.

Powered wheelchairs offer a means of independent mobility for older adults who are unable to walk and cannot propel a manual wheelchair. Unfortunately, cognitively impaired older adults may be denied this means of independent mobility. There is concern that these adults are unable to drive a powered wheelchair safely or properly. Intelligent wheelchairs offer an approach to address this problem. This research outlines the development and evaluation of an Intelligent Wheelchair System (IWS) that is proposed to make powered wheelchairs safer and easier to use for cognitively impaired older adults. The IWS has anti-collision and navigation functions. Hardware results show a 1000% increase in computational speed compared to the previous IWS. Clinical results with dementia patients show that the IWS has the potential to increase safety by reducing frontal collisions, and by promoting safe completion of movement tasks. Usability of the system may be an issue.

Powered wheelchairs offer a means of independent mobility for older adults who are unable to walk and cannot propel a manual wheelchair. Unfortunately, cognitively impaired older adults may be denied this means of independent mobility. There is concern that these adults are unable to drive a powered wheelchair safely or properly. Intelligent wheelchairs offer an approach to address this problem. This research outlines the development and evaluation of an Intelligent Wheelchair System (IWS) that is proposed to make powered wheelchairs safer and easier to use for cognitively impaired older adults. The IWS has anti-collision and navigation functions. Hardware results show a 1000% increase in computational speed compared to the previous IWS. Clinical results with dementia patients show that the IWS has the potential to increase safety by reducing frontal collisions, and by promoting safe completion of movement tasks. Usability of the system may be an issue.

People with severe motor-impairments due to Spinal Cord Injury (SCI) or Spinal Cord Dysfunction (SCD), often experience difficulty with accurate and efficient control of pointing devices (Keates et al., 02). Usually this leads to their limited integration to society as well as limited unassisted control over the environment. The questions “How can someone with severe motor-impairments perform mouse pointer control as accurately and efficiently as an able-bodied person?” and “How can these interactions be advanced through use of Computational Intelligence (CI)?” are the driving forces behind the research described in this paper. Through this research, a novel fuzzy mouse cursor control system (FMCCS) is developed. The goal of this system is to simplify and improve efficiency of cursor control and its interactions on the computer screen by applying fuzzy logic in its decision-making to make disabled Internet users use the networked computer conveniently and easily. The FMCCS core consists of several fuzzy control functions, which define different user interactions with the system. The development of novel cursor control system is based on utilization of motor functions that are still available to most complete paraplegics, having capability of limited vision and breathing control. One of the biggest obstacles of developing human computer interfaces for disabled people focusing primarily on eyesight and breath control is user’s limited strength, stamina, and reaction time. Within the FMCCS developed in this research, these limitations are minimized through the use of a novel pneumatic input device and intelligent control algorithms for soft data analysis, fuzzy logic and user feedback assistance during operation. The new system is developed using a reliable and cheap sensory system and available computing techniques. Initial experiments with healthy and SCI subjects have clearly demonstrated benefits and promising performance of the new system: the FMCCS is accessible for people with severe SCI; it is adaptable to user specific capabilities and wishes; it is easy to learn and operate; point-to-point movement is responsive, precise and fast. The integrated sophisticated interaction features, good movement control without strain and clinical risks, as well the fact that quadriplegics, whose breathing is assisted by a respirator machine, still possess enough control to use the new system with ease, provide a promising framework for future FMCCS applications. The most motivating leverage for further FMCCS development is however, the positive feedback from persons who tested the first system prototype.

Access technologies facilitate novel and alternative methods for individuals with disabilities to interact with their environment. Finding suitable access solutions for children with severe spastic quadriplegic cerebral palsy can be difficult because of their poor motor control and targeting abilities due to spasticity at the limbs, neck, and head. In this research a multiple camera tongue switch was developed for a 7 year-old case study participant with severe spastic quadriplegia. Remotely via video, this system reacts to tongue protrusions as cues for single-switch access. Having multiple cameras mitigates targeting problems with the head that conventional single camera systems would present. Results of a usability experiment with the participant show that good sensitivity (82%) and specificity (80%) can be achieved with a non-contact tongue protrusion access modality for a user with spastic quadriplegia. Moreover, the experiment verified that the extra cameras improve utility of video-based access technologies for the target population.

The haptic exploration of 2-D images is a challenging problem in computer haptics. Research on the topic has primarily been focused on the exploration of maps and curves. This thesis describes the design and implementation of a system for the haptic exploration of photographs. The system builds on various research directions related to assistive technology, computer haptics, and image segmentation. An object-level segmentation hierarchy is generated from the source photograph to be rendered haptically as a contour image at multiple levels-of-detail. A tool for the authoring of object-level hierarchies was developed, as well as an innovative type of user interaction by region selection for accurate and efficient image segmentation. According to an objective benchmark measuring how the new method compares with other interactive image segmentation algorithms shows that our region selection interaction is a viable alternative to marker-based interaction. The hierarchy authoring tool combined with precise algorithms for image segmentation can build contour images of the quality necessary for the images to be understood by touch with our system. The system was evaluated with a user study of 24 sighted participants divided in different groups. The first part of the study had participants explore images using haptics and answer questions about them. The second part of the study asked the participants to identify images visually after haptic exploration. Results show that using a segmentation hierarchy supporting multiple levels-of-detail of the same image is beneficial to haptic exploration. As the system gains maturity, it is our goal to make it available to blind users.

The CopyCat project is an interdisciplinary effort to create a set of computer-aided language learning tools for deaf children. The CopyCat games allow children to interact with characters using American Sign Language (ASL). Through Wizard of Oz pilot studies we have developed a set of games, shown their efficacy in improving young deaf children's language and memory skills, and collected a large corpus of signing examples. Our previous implementation of the automatic CopyCat games uses automatic sign language recognition and verification in the infrastructure of a memory repetition and phrase verification task. The goal of my research is to expand the automatic sign language system to transition the CopyCat games to include the flexibility of a dialogue system. I have created a labeling ontology from analysis of the CopyCat signing corpus, and I have used the ontology to describe the contents of the CopyCat data set. This ontology was used to change and improve the automatic sign language recognition system and to add flexibility to language use in the automatic game.

A brain-machine interface (BMI) uses signals from the brain to control electronic devices. One application of this technology is the control of assistive devices to facilitate movement after paralysis. Ideally, the BMI would identify an intended movement and control an assistive device to produce the desired movement. To implement such a system, it is necessary to identify different movements involving a single limb and users must be able to issue commands at any instant instead of only during specific time windows determined by the BMI itself. A novel processing technique to identify voluntary movements using only four electrodes is presented. Histograms containing the spectral components of intracranial neural signals displaying power changes correlated with movement were unique for each of three movements performed with one limb. Off-line classification of the histograms allowed the identification of the performed movement with an accuracy of 89%. This movement identification system was interfaced with a neuroprosthesis for grasping, fitted to a tetraplegic individual. The user pressed a button triggering the random selection and classification of a brain signal previously recorded intracranially from a different person while performing specific arm movements. Correct identification of the movement triggered grasping functions. Movement identification accuracy was 94% allowing successful operation of the neuroprosthesis. Finally, two BMIs for the real-time asynchronous control of two-dimensional movements were created using a single electrode. One EEG-based system was tested by a healthy participant. A second system was implemented and tested using recordings from an individual undergoing clinical intracranial electrode implantation. The users modulated their 7 Hz-13 Hz oscillatory rhythm through motor imagery. A power decrease below a threshold activated a ``brain-switch''. This switch was coupled with a novel asynchronous control strategy to control a miniature remotely-controlled vehicle as well as a computer cursor. Successful operation of the EEG system required 6 hrs of training. ECoG control was achieved after only 15 minutes. The operation of the BMI was simple enough to allow users to focus on the task at hand rather than on the actual operation of the BMI.

This study investigates the effects of intensive remediation in reading and assistive technology skills combined with the use of a computer based text to speech reader in a six-week intensive reading program for junior-age students with reading disabilities. The study reports on the strategies used by the teachers, week-by-week student progress, and the results of a criterion-referenced reading assessment. Other themes include student attitudes towards the technology and barriers to implementation. Findings indicate that a computer based text to speech reader provides significant compensatory support, resulting in improved fluency and comprehension scores. Students using technology were able to access paper and on-line text at a higher level. A model which builds on the work of Dyck and Pemberton (2002) and Edyburn (2004b, 2007) is proposed which provides a theoretical framework to assist schools in decisions about remediation or compensation for struggling readers in primary, junior, intermediate, and senior grades.

Assistive technology, specifically, word prediction software holds great promise in supporting the writing process for students with learning disabilities. This thesis reports on a qualitative study that examined eight students’ self-perceptions as learners and writers using word prediction software. Participants were purposefully recruited from a local Learning Disabilities Association’s listserv located in a mid-sized Eastern Ontario city. Three groups of two to three Grades 4-8 students previously identified with a learning disability, and who were already using word prediction software (e.g. Co-Writer or WordQ), attended a 3-hour session. This session included an instructional workshop, and completion of a short reflective writing task followed by a focus group. Separately, participants’ parents attended a focus group. Data for this study includes focus group responses (student and parent), observations from the workshop, and the written student reflections. Using content analysis, emerging themes from participant responses were analyzed. The main themes from this analysis were: (1) students’ perceptions of having an equal opportunity to participate in academic subjects; (2) increased student self-efficacy; and (3) an ad hoc approach to training and the use of assistive technology software in school. These themes were then linked to relevant literature and a set of recommendations was developed for educators. Recommendations for the future included facilitating increased self-efficacy for students with learning disabilities; reducing the ad hoc approach to teacher education by instituting mandatory courses about students with disabilities in teacher education programs; and increased instruction in the use of assistive technology for parents and teachers. / Thesis (Master, Education) -- Queen's University, 2011-06-27 22:45:11.704