CIRCLING INTERFACE: AN ALTERNATIVE INTERACTION METHOD FOR ON-SCREEN OBJECT MANIPULATION

An alternative interaction method, called the circling interface, was developed and evaluated for individuals with disabilities who find it difficult or impossible to consistently and efficiently perform pointing operations involving the left and right mouse buttons. The circling interface is a gesture-based interaction technique. To specify a target of interest, the user makes a circling motion around the target. To specify a desired pointing command with the circling interface, each edge of the screen is used. The user selects a command before circling the target. Empirical evaluations were conducted with human subjects from three different groups (individuals without disability, individuals with spinal cord injury, and individuals with cerebral palsy), comparing each group's performance on pointing tasks with the circling interface to performance on the same tasks when using a mouse button or dwell-clicking software. Across all three groups, the circling interface was faster than the dwelling interface (although the difference was not statistically significant). For the single-click operation, the circling interface was slower than dwell selection, but for both double-click and drag-and-drop operations, the circling interface was faster. In terms of performance accuracy, the results were mixed: for able-bodied subjects circling was more accurate than dwelling, for subjects with SCI dwelling was more accurate than circling, and for subjects with CP there was no difference. However, if errors caused by circling on an area with no target or by ignoring circles that are too small or too fast were automatically corrected by the circling interface, the performance accuracy of the circling interface would significantly outperform dwell selection. This suggests that the circling interface can be used in conjunction with existing pointing techniques and this combined approach may provide more effective mouse use for people with pointing problems. Consequently, the circling interface can improve clinical practice by providing an alternative pointing method that does not require physically activating mouse buttons and is more efficient than dwell-clicking. It is also expected to be useful for both computer access and augmentative communication software

Effectiveness of Morse Code as an Alternative Control Method for Powered Wheelchair Navigation

We applied Morse code as an alternative input method for powered wheelchair navigation to improve driving efficiency for individuals with physical disabilities. In lab trials performed by four testers, it demonstrated significant improvement in driving efficiency by reducing the driving time, compared to traditional single switch wheelchair navigation

Computer Access Technologies for Controlling Assistive Robotic Manipulators: Potentials and Challenges

One of the most challenging barriers to a successful application of the assistive robots is how to enable users who have special needs to interact with the robot aids in an efficient and comfortable manner, since the conventional control method using a traditional joystick combined with buttons and/or knobs demands fine motor control and good dexterity resulting in cognitive and physical workload. Adopting computer access technology, which has provided an alternative means to allow people who have a wide range of special needs to independently access their computer, can be a practical solution to this issue. In this paper, we reviewed and discussed the potentials and challenges of computer access technologies as an alternative control method for controlling assistive robotic manipulators, focusing on most widely adopted interventions in the clinical settings, including alternative pointing, keyboard-only access, switch scanning interface and speech recognition

Modeling an Automatic Adjustment of Scanning Rate Using Fuzzy Inference Logic

Single-switch scanning is one of the slowest way for people with severe motor impairments to access a wide range of assistive technologies, such as entering text into computer applications, manipulating alternative and augmentative communication devices, and operating power wheelchairs. Automating scanning rate adjustment has been investigated as a means of improving selection rate by several research groups [1-6], using probabilistic methods such as uncertainty factors and Bayesian networks. In practice, however, when assessing and documenting their client’s needs, clinicians tend to prefer specifying linguistic values, such as slow, medium, and fast, rather than numerical values. In this respect, fuzzy logic can be an alternative to the existing approaches because it can capture the meaning of linguistic variables whose values are words rather than numbers [7, 8]. This paper describes our approach to modeling the automatic adjustment of scan rate using fuzzy logic

Three Dimentional Computer Vision-Based Alternative Control Method for Assistive Robotic Manipulator

JACO (Kinova Technology, Montreal, QC, Canada) is an assistive robotic manipulator that is gaining popularity for its ability to assist individuals with physical impairments in activities of daily living. To accommodate a wider range of user population especially those with severe physical limitations, alternative control methods need to be developed. In this paper, we presented a vision-based assistive robotic manipulation assistance algorithm (AROMA) for JACO, which uses a low-cost 3D depth sensing camera and an improved inverse kinematic algorithm to enable semi-autonomous or autonomous operation of the JACO. The benchtop tests on a series of grasping tasks showed that the AROMA was able to reliably determine target gripper poses. The success rates for the grasping tasks ranged from 85% to 100% for different objects

ARoMA-V2: Assistive Robotic Manipulation Assistance with Computer Vision and Voice Recognition

We have designed and developed a handy alternative control method, called ARoMA-V2 (Assistive Robotic Manipulation Assistance with computer Vision and Voice recognition), for controlling assistive robotic manipulators based on computer vision and user voice recognition. Potential advantages of ARoMA-V2 over the traditional alternatives include: providing completely hands-free operation; helping a user to maintain a better working posture; Allowing the user to work in postures that otherwise would not be effective for operating an assistive robotic manipulator (i.e., reclined in a chair or bed); supporting task specific commands; providing the user with different levels of intelligent autonomous manipulation assistances; giving the user the feeling that he or she is still in control at any moment; and being compatible with different types of new and existing assistive robotic manipulators

Shared Control of Assistive Robotic Manipulators

The continuum of controlling an assistive robotic manipulator (ARM) ranges from manual control to full autonomy. Shared control of an ARM operates in the space between manual control and full autonomy. This paper reviews the status quo on shared control of ARMs. Though users and ARMs can divide responsibilities for a manipulation task in different ways, most research in this area focus on maximizing robot autonomy and minimizing user control, while other work split the responsibilities more evenly between the ARM and the user. User studies in this area are very limited. More research is needed to investigate the overall performance, workload, and satisfaction across different levels of autonomy for the shared control of ARMs

Hydrogenated polymorphous silicon: establishing the link between hydrogen microstructure and irreversible solar cell kinetics during light soaking

This thesis is dedicated to hydrogenated polymorphous silicon (pm-Si:H) and solar cells based on this material. pm-Si:H is a nanostructured thin film deposited by conventional PECVD method. The effects of various deposition parameters (gas flow ratio, pressure, RF power, Ts) on material properties were investigated in order to optimize its quality. The strategy was to combine a wide range of diagnostics (spectroscopic ellipsometry, hydrogen exodiffusion, SIMS, FTIR, AFM, etc.). Due to the contribution of plasma synthesized silicon nanoparticles, the process condition of pm-Si:H shows the difference in contrary to a-Si:H deposition through ionized radicals. Studies on pm-Si:H deposition process allows to fabricate pm-Si:H PIN solar cells with a high initial efficiency of 9.22 % and fill factor of 74.1, but also demonstrate unusual light-induced effects, namely i) a rapid initial degradation, ii) an irreversible degradation, and iii) large macroscopic structural changes. Comprehensive investigation on the light-induced degradation kinetics of pm-Si:H PIN layer stacks reveals a pronounced hydrogen accumulation and delamination at the substrate/p-type layer interface under light-soaking, leading to macroscopic structural changes, e.g., peel-off and solar cell area loss. We have found that a PIN structure leads to facilitated delamination during lightsoaking, which we attribute to hydrogen accumulation at the substrate/p-layer interface, while use of a NIP structure prevents the hydrogen accumulation and delamination. This lead us to fabricate pm-Si:H NIP solar cells showing a high stabilized efficiency of 8.43 %, that shows a small (10 %) light-induced degradation after light-soaking for 500 hours.Cette thèse est consacrée au silicium polymorphe hydrogéné (pm-Si:H). Elle porte tout d'abord sur une étude du pm-Si :H puis sur une étude des cellules photovoltaïques fabriquées à partir de ce matériau. Le pm-Si:H est formé de couches minces nanostructurées et peut être déposé par PECVD conventionnelle. Les effets des différents paramètres de dépôt (mélanges gazeux, pression, puissance RF, température du substrat) sur les propriétés du matériau ont été étudiés pour optimiser sa qualité. La caractérisation des couches a été un enjeu primordial. Pour cela, nous avons choisi de combiner une palette très large de méthodes de caractérisation (ellipsomètrie spectroscopique, exodiffusion d'hydrogène, SIMS, FTIR, AFM, etc...). A cause de la contribution des nanoparticules de silicium dans le plasma, la nature du dépôt du pm-Si:H montre la différence contrairement au a-Si:H pour lequel le dépôt se fait par le biais de radicaux ionisés. L'étude des conditions du procédé nous a conduit à fabriquer des cellules solaires d'un rendement initial de 9.22 % avec un facteur de forme élevé (74.1), mais aussi de démontrer des effets de vieillissement inhabituels, tels que i) une dégradation initiale rapide, ii) une dégradation irréversible, et iii) de grands changements structuraux macroscopiques. Nous avons découvert que le principal problème se situe entre le substrat et la couche mince de silicium. L'hydrogène moléculaire diffuse et s'accumule à l'interface entre le substrat et la couche mince, ce qui introduit un délaminage local qui a pour conséquence une dégradation initiale rapide des performances des cellules. Nous avons trouvé que sous éclairement une structure PIN facilite l'accumulation d'hydrogène et le délaminage à l'interface entre le substrat et la couche dopée p. Cependant, l'utilisation d'une structure NIP empêche l'accumulation d'hydrogène et le délaminage. Cela nous a permis de fabriquer des cellules solaires pm-Si:H de structure NIP d'un rendement stable de 8.43 %, mais aussi de démontrer une degradation minimale (10 %) après un vieillissement de 500 heures

The Use of Microsoft Windows on Intel-Based McIntosh Platform

The successful use of micro computers is regarded as the fundamental necessity for an occupational and educational placement of people with visual impairments. People with visual impairments have long been actively adopting computers and assistive technology devices as integral parts of their lives. For example, 2002 NTIA survey reported that people with visual impairments use computers more often than people who are sighted in the area of playing games, searching for information on products or services, making online purchases, and gathering information on news, weather, and sports. It further suggested that people with visual impairments use E-Mail as a significant means of communication. From a technological standpoint, number of products, protocols, and guidelines are devised to facilitate the use of computers. As a result, people with visual impairments now have relatively rich options to choose when completing tasks using computers. For example, several screen reading products are available in assisting visually impaired users for accessing information on computer screen. However, it has also been factual that people with visual impairments have limitations in choosing appropriate platforms that these assistive technology software could be operated. Over the years, the personal computer market has been divided by IBM-based open architecture computers and Power-PC based McIntosh computers. On the other hand, it can also be viewed from the point of the operating systems, where Microsoft Windows and Apple’s proprietary operating system. Data made available by Net Applications credits Mac OS X with a share of 7.31% of the operating system market with Windows at 91.79%. Out of this, Windows Vista accounts for 10.48% while Mac OS has 3.28% and Mac Intel 76.91%. The figures released by Net Applications are illustrative of the operating system market at the end of December 2007. Wide selection of assistive technology software and hardware devices for people with visual impairments were developed on Microsoft Window-based platform and as a result, visually impaired computer users were limited to Intel-based computers. Furthermore, assistive technology specialists were limited to Microsoft Window-based computers as well because more software used by their clients were developed on this platform. In 2005, Apple decided to use Intel-based chipsets and processors on their personal computers, making it possible for the Windows operating system run natively on the architecture

On-screen Target Acquisition through Mouse Movement Recognition

In this paper we present a new design idea as an alternative to improve on-screen target acquisition for individuals who have difficulty pointing by inferring the user’s intended target from the user’s mouse movements. The intended target is inferred based on real-time mouse movement information and the properties of all user interface elements currently displayed on the computer screen. During preliminary testing of the prototype application, the software reduced pointing errors and the physical effort needed to operate a pointing device. The software is compatible with a range of existing pointing technologies