Frédéric Vella

Using visual cues to help text entry on PDAs

Text input enhancement is well suited as soon as degraded conditions are encountered, whether due to handicap or use while moving. We propose a novel text input assistance, based on the AZERTY soft keyboard, whose keys are selected one by one thanks to a pointing device. The keys likely to be selected are predicted and contrasted in order to help users visually. We postulate that this kind of help facilitates and accelerates input for novice users under degraded conditions. We have computed the theoretical reduction in time, thanks to the Hick-Hyman law: the theoretical gain, for a novice, is 50%). We plan to further improve help robustness and to carry out empirical validations of the prototype.

Investigating drag and drop techniques for older people with cognitive impairment

Graphical user interfaces and interactions that involve pointing to items and dragging them are becoming more common in rehabilitation and assistive technologies. We are currently investigating interaction techniques to understand point-select-drag interactions for older people with cognitive impairment. In particular, this study reports how older perform such tasks. Significant differences in behavior between all of the interaction techniques are observed and the reasons for these differences are discussed according the Mini Mental Score.

The virtual paddle: an universal interaction for accessible video games

The video games are often inaccessible to disabled motor people of the upper limbs. The specialized games are limited choice of the set of accessible games. We present a new accessible technique of interaction: the Virtual Paddle. We designed it with a user-centered method. It is composed of three steps: questionnaire, brainstorming and paper prototypes. Next, we present the experiment to choose the optimized paddle. Finally we discuss the results and our perspective.

Design and evaluation of Multi-function Scanning System : a case study

We present in this paper an assistive technology of communication and command for quadriplegics. To carry out this assistive technology, a user centered design approach with the patient, his occupational therapists and his family was conducted. Various iterative versions of the prototype have been defined by means of the SOKEYTO platform to meet the needs and the abilities of the quadriplegic person. Options carried out and consecutive choice will be reported as well the difficulties to implement. The assistive technology was used by one quadriplegic person. A qualitative evaluation is also reported.

Adaptation of AAC to the context communication: a real improvement for the user illustration through the VITIPI word completion

This paper describes the performance of the VITIPI word completion system through a text input simulation. The aim of this simulation is to estimate the impact of the linguistic knowledge base size through two metrics: the Key-Stroke Ratio (KSR) and the KeyStroke Per Character (KPC). Our study shows that the performance of a word completion is depending of the % of words not available and the size of the lexicon.

Fitts's law interpretation as ergonomic metrics for motor impaired users

One of the key challenges in developing assistive technology for elder and handicapped people is finding effective means of interaction. Improved target selection has been the topic of many studies in the human–computer interaction (HCI), where the models may also be applied to any graphic user interfaces for disabled people. Fitts’s law (Fitts 1954) was used as an adopted model (Soukoreff and MacKenzie 2004) to predict moving and pointing movements that are required to interact with graphic user interfaces. Fitts’s law establishes relationship between movement time, distance and accuracy. The formulation proposed in Gump et al. (2002) is

Techniques d'optimisation de la saisie de texte sur clavier virtuel

This video aims to show the optimization technics developed in the DIAMANT team to help the motor disabled people to input text with a virtual key-board. The results expected by these technics are to increase the typing rate (words per minute) and in consequence to reduce their motor and eye trouble fatigue.

Transforming medico-educators into design partners to build HMK, a mathematical input keyboard for second graders

Children with severe motor disabilities experience motor fatigue when inputting mathematica formulas with applications such as Open Office or Microsoft Office. To mitigate this feeling we have implemented a user-centred design method for the design of a virtual keyboard for mathematical input called HMK. The objective of this article is to show how mediators of medico-educational can contribute to the design of HMK for college students and high school students with neuro motor handicaps.

HandiMathKey: Mathematical Keyboard for Disabled Person

To type mathematical formula is a tedious task for all of us with the usual applications. Moreover, this task is very tiring for motor impairment. This paper describes the user centred methodology used to design the HandiMathKey virtual keyboard to type more easily the mathematical formula. Then we present a case study that compares the entry time between HandiMathKey and Word office for the mathematic formulas typing. This study shows that the HandiMathkey is easier to use and more efficient.

EyeSchool: An Educational Assistive Technology for People with Disabilities - Passing from Single Actors to Multiple-Actor Environment

Since 2005, public policy in France has strongly been encouraging young people with disabilities inclusion within the regular school system. This has found a direct application through technical innovation, intended to help students being more independent within their learning activities. In this context, the purpose of this paper is to underline the manner in which using assistive information and communication technologies may improve the inclusive education for people with disabilities. The case study we present underlines the complexity of the social world into which the use of a precise assistive tool takes it place.