Kevin Caves

Using mobile phones to write in air

Numerous sensors in modern mobile phones enable a range of people-centric applications. This paper envisions a system called PhonePoint Pen that uses the in-built accelerometer in mobile phones to recognize human writing. By holding the phone like a pen, a user should be able to write short messages or draw simple diagrams in the air. The acceleration due to hand gestures can be translated into geometric strokes, and recognized as characters. We prototype the PhonePoint Pen on the Nokia N95 platform, and evaluate it through real users. Results show that English characters can be identified with an average accuracy of 91.9%, if the users conform to a few reasonable constraints. Future work is focused on refining the prototype, with the goal of offering a new user-experience that complements keyboards and touch-screens.

Enhancing AAC connections with the world

The availability of new technologies has changed how we control devices, exchange information, and communicate with others. Significant barriers, however, have prevented many individuals who use augmentative and alternative communication (AAC) from accessing the technology and computer-based activities available in todays “Information Society.” In this paper we discuss the benefits and challenges to increased interoperability between AAC and mainstream technologies. We outline suggested roles and activities for six stakeholder groups: (a) individuals who use AAC, (b) individuals who assist in selecting and supporting use of AAC devices, (c) AAC researchers, (d) AAC device manufacturers, (e) mainstream application developers and technology manufacturers, and (f) public policy makers. We also provide suggestions for future research, public policy, and technical development.

Increasing BCI communication rates with dynamic stopping towards more practical use: an ALS study

OBJECTIVE The P300 speller is a brain-computer interface (BCI) that can possibly restore communication abilities to individuals with severe neuromuscular disabilities, such as amyotrophic lateral sclerosis (ALS), by exploiting elicited brain signals in electroencephalography (EEG) data. However, accurate spelling with BCIs is slow due to the need to average data over multiple trials to increase the signal-to-noise ratio (SNR) of the elicited brain signals. Probabilistic approaches to dynamically control data collection have shown improved performance in non-disabled populations; however, validation of these approaches in a target BCI user population has not occurred. APPROACH We have developed a data-driven algorithm for the P300 speller based on Bayesian inference that improves spelling time by adaptively selecting the number of trials based on the acute SNR of a users EEG data. We further enhanced the algorithm by incorporating information about the users language. In this current study, we test and validate the algorithms online in a target BCI user population, by comparing the performance of the dynamic stopping (DS) (or early stopping) algorithms against the current state-of-the-art method, static data collection, where the amount of data collected is fixed prior to online operation. MAIN RESULTS Results from online testing of the DS algorithms in participants with ALS demonstrate a significant increase in communication rate as measured in bits/min (100-300%), and theoretical bit rate (100-550%), while maintaining selection accuracy. Participants also overwhelmingly preferred the DS algorithms. SIGNIFICANCE We have developed a viable BCI algorithm that has been tested in a target BCI population which has the potential for translation to improve BCI speller performance towards more practical use for communication.

AAC performance and usability issues: the effect of AAC technology on the communicative process.

In this article, Clarks theory of language use is applied to the study of conversations of augmented speakers and their addressees. Discussion focuses on how shared meaning—called common ground—is achieved, the process of grounding utterances under real-time constraints, and how the media characteristics of devices affect the grounding process. A joint action analysis of grounding will be applied to examples of word-board and Voice Output Communication Aid (VOCA)-mediated conversations to show how participants organize their talk around specific media constraints to conduct their conversations and solve communication problems. The authors argue that this model of device-mediated communication performance, or some variety of it, has the potential to reconcile many of the individual research findings in this field within a single explanatory framework. If successful, this approach could be used to evaluate future research with an empirically-based model of communication performance.

A quality assurance study on the accuracy of measuring physical function under current conditions for use of clinical video telehealth.

OBJECTIVE To determine whether conditions for use of clinical video telehealth technology might affect the accuracy of measures of physical function. DESIGN Repeated measures. SETTING Veterans Administration Medical Center. PARTICIPANTS Three healthy adult volunteers for a sample size of n=30 independent trials for each of 3 physical function tasks. INTERVENTIONS None. MAIN OUTCOME MEASURES Three tasks capturing differing aspects of physical function: fine-motor coordination (number of finger taps in 30s), gross-motor coordination (number of gait deviations in 10ft [3.05m]), and clinical spatial relations (identifying the proper height for a cane randomly preset ±0-2in [5.1cm] from optimal), with performance simultaneously assessed in person and video recorded. Interrater reliability and criterion validity were determined for the measurement of these 3 tasks scored according to 5 methods: (1) in person (community standard), (2) slow motion review of the video recording (criterion standard), and (3-5) full speed review at 3 Internet bandwidths (64kps, 384kps, and 768kps). RESULTS Fine-motor coordination-Interrater reliability was variable (r=.43-.81) and criterion validity was poor at 64kps and 384kps, but both were acceptable at 768kps (reliability r=.74, validity β=.81). Gross-motor coordination-Interreliability was variable (range r=.53-.75) and criterion validity was poor at all bandwidths (β=.28-.47). Motionless spatial relations-Excellent reliability (r=.92-.97) and good criterion validity (β=.84-.89) at all the tested bandwidths. CONCLUSIONS Internet bandwidth had differing effects on measurement validity and reliability for the fine-motor task, the gross-motor task, and spatial relations, with results for some tasks at some transmission speeds well below acceptable quality standards and community standards.

Concerns Regarding the Application of Restrictive "Eligibility" Policies to Individuals Who Need Communication Services and Supports: A Response by the National Joint Committee for the Communication Needs of Persons with Severe Disabilities

Sometimes communication supports and services for school-aged children with extensive disabilities are re-duced over time or removed on the basis of inappropri-ate reasons or eligibility criteria that are flawed. Family members may feel unequipped to argue against the de-cisions that schools or agencies make for their child, and professionals may be in a difficult position to disagree with their administrators. The National Joint Committee for the Communication Needs of Persons with Severe Disabilities has written a position statement on these re-strictive eligibility practices. This position statement ad-dresses concerns about inappropriate eligibility criteria and may be used to help individuals, family members, and providers gain access to necessary communication supports and services.

Extraction of spatial information for low-bandwidth telerehabilitation applications.

Telemedicine applications, based on two-dimensional (2D) video conferencing technology, have been around for the past 15 to 20 yr. They have been demonstrated to be acceptable for face-to-face consultations and useful for visual examination of wounds and abrasions. However, certain telerehabilitation assessments need the use of spatial information in order to accurately assess the patients condition and sending three-dimensional video data over low-bandwidth networks is extremely challenging. This article proposes an innovative way of extracting the key spatial information from the patients movement during telerehabilitation assessment based on 2D video and then presenting the extracted data by using graph plots alongside the video to help physicians in assessments with minimum burden on existing video data transfer. Some common rehabilitation scenarios are chosen for illustrations, and experiments are conducted based on skeletal tracking and color detection algorithms using the Microsoft Kinect sensor. Extracted data are analyzed in detail and their usability discussed.

Connecting AAC devices to the world of information technology.

Modern day information technology (IT) is converging around wireless networks. It is now possible to check E-mail and view information from the World Wide Web from commercially available mobile phones. For individuals with disabilities, the ability to access multiple and different types of information not only promises convenience, but also can help to promote independence and facilitate access to public and private information systems. There are many barriers to access for people with disabilities, including technological hurdles, security, privacy, and access to these emerging wireless technologies. However, legislation, advocacy, standards, and research and development can ensure that users of augmentative and alternative communication (AAC) and assistive technology have access to these technologies. This article provides a historical context for the field of AAC and IT development, a review of the current state of these technologies, a glimpse of the potential of wireless information access for the lives of AAC users, and a description of some of the barriers and enablers to making access available to users of AAC and assistive technologies.

One Size Does Not Fit All—Mobility Device Type Affects Speed, Collisions, Fatigue, and Pain

OBJECTIVE To determine whether differences could be detected in mobility outcomes during community mobility and home mobility tasks according to type of mobility assistive device. DESIGN Randomized, repeated measures. SETTING Community mobility task: traversing 341.4m between the rehabilitation clinic and hospital entrance; home mobility task: traversing 39m into and out of a patient training bathroom and bedroom. PARTICIPANTS Community-dwelling, cognitively intact ambulatory veterans (N=59) who used a mobility device within the 14 days prior to the study. INTERVENTIONS Participants tested 3 types of mobility assistive devices with wheels: 4-wheeled walker (WW), manual wheelchair (MWC), and powered wheelchair (PWC). The first and last devices used by each participant were randomly assigned as either MWC or WW. The PWC was always the second device. MAIN OUTCOMES MEASURES Speed (m/s), collisions (total), fatigue (0-10 Likert scale), and pain (0-10 Likert scale, diagram). RESULTS The community mobility task was performed with all 3 devices by 52 (88%) veterans, and the home mobility task was performed with all 3 devices by 53 (90%) participants. In each task, 28 participants used the WW and 28 participants used the MWC as the final device. In the community mobility task, statistically significant differences (P<.05) were seen with ≥1 device comparison for all studied outcomes (eg, standardized mean difference for the MWC compared with the PWC showed -.67 fewer collisions for the MWC). In the home mobility task, speed, collisions, and fatigue showed statistically significant (P<.05) device-related differences (eg, standardized mean difference for the WW compared with the MWC showed -.88 fewer collisions for the WW). CONCLUSIONS We found statistically significant and substantively different effects from 3 commonly used mobility assistive devices with wheels on diverse mobility outcomes when used in typical community mobility and home mobility tasks, providing proof of concept support for a research methodology applicable to comparative outcome studies of diverse mobility aids.

A Pilot Study of Partial Unweighted Treadmill Training in Mobility-Impaired Older Adults

Background. Partial unweighted treadmill training is a potentially effective modality for improving fitness and function in frail elders. We tested the feasibility of partial unweighted treadmill training in older, mobility-impaired veterans. Methods. Eight mobility-impaired elders participated in partial unweighted treadmill training three times/week for twelve weeks. Outcome measures included gait speed, performance-oriented mobility assessment (POMA), eight foot up and go, and the SF-36 physical functioning short form. Results. There was significant improvement in treadmill walking time (+8.5 minutes; P < 0.001), treadmill walking speed (+0.14 meters/second; P = 0.02), and percent of body weight support (−2.2%; P = 0.02). Changes in physical performance included usual gait speed (+0.12 meters/second; P = 0.001), rapid gait speed (+0.13 meters/second; P = 0.01), POMA (+2.4 summary score; P < 0.001), and eight foot up and go (−1.2 seconds; P = 0.05). Conclusions. Partial unweighted treadmill training is feasible in mobility-impaired elders. Improvements in treadmill training capacity resulted in clinically meaningful improvements in fitness levels and improved mobility.