A Hand-Held Device Presenting Haptic Directional Cues for the Visually Impaired

Haptic information is essential in everyday activities, especially for visually impaired people in terms of real-world navigation. Since human haptic sensory processing is nonlinear, asymmetric vibrations have been widely studied to create a pulling sensation for the delivery of directional haptic cues. However, the design of an input control signal that generates asymmetric vibrations has not yet been parameterised. In particular, it is unclear how to quantify the asymmetry of the output vibrations to create a better pulling sensation. To better understand the design of an input control signal that generates haptic directional cues, we evaluated the effect of the pulling sensations corresponding to the three adjustable parameters (i.e., delay time, ramp-down step length, and cut-off voltage) in a commonly applied step-ramp input signal. The results of a displacement measurement and a psychophysical experiment demonstrate that when the quantified asymmetry ratio is in a range of 0.3430-0.3508 with an optimised cut-off voltage for our hand-held device, the haptic directional cues are better perceived by participants. Additionally, the results also showed a superior performance in haptic delivery by shear forces than normal forces.

Conceptualizations of well-being in adults with visual impairment: A scoping review

Background

Despite its ubiquity, it is often not clear what organizations and services mean by well-being. Visual impairment (VI) has been associated with poorer well-being and well-being has become a key outcome for support and services for adults living with VI. A shared understanding of what well-being means is therefore essential to enable assessment of well-being and cross-service provision of well-being support.

Objectives

To provide an overview of the ways in which well-being has been conceptualized in research relating to adults living with VI.

Eligibility criteria

Articles were included in the review if the article discussed well-being in the context of adults living with VI, was available in English and as a full text.

Data sources

A systematic search using search terms relating to VI and well-being was conducted in EBSCOHost (Medline, CINHL) and Ovid (Embase Classic, Embase, Emcare 1995, Health + Psychosocial, HMIC Health Management Info, APA, PsycArticles, PsycInfo, PsycTests).

Charting

A team of three reviewers screened titles, abstracts and full-texts articles and extracted data. Ambiguous articles were referred to the research group and discussed.

Results

Of 10,662 articles identified in the search, 249 were included in the review. These referred to 38 types of well-being. The most common types were general well-being (n = 101; 40.6%) emotional well-being (n = 86, 34.5%) and psychological well-being (n = 66, 26.5%). Most articles (n = 150; 60.2%) referred to one type only, with a maximum of 9 listed in one article. A large number of articles did not clearly define well-being. A wide range of indicators of well-being related to the domains of hedonia, mood, positive and negative affect, quality of life, mental health, eudaimonia, self/identity, health, psychological reactions to disability and health problems, functioning, social functioning and environment, were extracted, many of which were used just once.

Conclusions

There remains a lack of consensus on how well-being is conceptualized and assessed in the context of adult VI. A standardized multi-domain approach derived with input from adults with VI and practitioners working with them is required to enable comparison of findings and cross-organizational provision of support.