Augmented and virtual reality experiences present significant barriers for disabled people, making it challenging to fully engage with immersive platforms. Whilst researchers have started to explore potential solutions addressing these accessibility issues, we currently lack a comprehensive understanding of research areas requiring further investigation to support the development of inclusive AR/VR systems. To address current gaps in knowledge, we led a series of multidisciplinary sandpits with relevant stakeholders (i.e., academic researchers, industry specialists, people with lived experience of disability, assistive technologists, and representatives from disability organisations, charities, and special needs educational institutions) to collaboratively explore research challenges, opportunities, and solutions. Based on insights shared by participants, we present a research agenda identifying key areas where further work is required in relation to specific forms of disability (i.e., across the spectrum of physical, visual, cognitive, and hearing impairments), including wider considerations associated with the development of more accessible immersive platforms.

This paper presents an assessment of the variability in freehand grasping of virtual objects in an exocentric mixed reality environment. We report on an experiment covering 480 grasp based motions in the transition phase of interaction to determine the level of variation to the grasp aperture. Controlled laboratory conditions were used where 30 right-handed participants were instructed to grasp and move an object (cube or sphere) using a single medium wrap grasp from a starting location (A) to a target location (B) in a controlled manner. We present a comprehensive statistical analysis of the results showing the variation in grasp change during this phase of interaction. In conclusion we detail recommendations for freehand virtual object interaction design notably that considerations should be given to the change in grasp aperture over the transition phase of interaction.

This article presents an analysis into the accuracy and problems of freehand grasping in exocentric Mixed Reality (MR). We report on two experiments (1710 grasps) which quantify the influence different virtual object shape, size and position has on the most common physical grasp, a medium wrap. We propose two methods for grasp measurement, namely, the Grasp Aperture (GAp) and Grasp Displacement (GDisp). Controlled laboratory conditions are used where 30 right-handed participants attempt to recreate a medium wrap grasp. We present a comprehensive statistical analysis of the results giving pairwise comparisons of all conditions under test. The results illustrate that user Grasp Aperture varies less than expected in comparison to the variation of virtual object size, with common aperture sizes found. Regarding the position of the virtual object, depth estimation is often mismatched due to under judgement of the z position and x, y displacement has common patterns. Results from this work can be applied to aid in the development of freehand grasping and considered as the first study into accuracy of freehand grasping in MR, provide a starting point for future interaction design.

This paper presents a first study into the use of dual view visual feedback in an exocentric MR environment for assisting freehand grasping of virtual objects. Recent work has highlighted problems associated with user errors in freehand grasping, via an analysis of virtual object type, location and size. Our work presents an extension to this, where 30 participants are recruited for two experiments (one assessing object size and the second object position), giving 1710 grasps in total. We report on results following the same protocol of the aforementioned study using a dual view visual feedback method. Results show that dual view visual feedback significantly increases user z placement accuracy and improves grasp placement in the x and y axes, however completion time is significantly higher. No improvement was found in user grasp aperture using dual view visual feedback for changes in object size and position.