Accessibility of Virtual Reality Environments

Overview

• Virtual reality replaces the real world with a virtual environment created by software. e.g. Oculus Rift, HTC vive, Google cardboard
• Augmented reality supplements the real world with virtual objects. e.g. Microsoft Hololens, Google Glass
• Virtual reality has had mixed reviews from users with disabilities
• Pro: Allows users to experience situations that they cannot control in real life
• Pro: Can offers improved spatial awareness and hand/eye coordination
• Pro: Lends itself to peer mentoring for those requiring assistance
• Pro: Virtual reality is perceived favorably by the public, particularly when linked to theraputic outcomes ⁷
• Con: Virtual reality has a lot of blue-sky thinking associated with it. Viewing virtual reality as a 'cure' for disability raises a number of ethical considerations
• Con: Users who experience difficulties may choose abandon virtual experiences rather than seek assistance

Mobility

• Pro: Virtual environments can offer users the ability to overcome real world physical barriers
• Pro: Avatars allows users to customise how they present themselves to others. Some users choose an avatar with a wheelchair, others do not: some switch between avatars with and without mobility aids ¹
• Con: Interaction in virtual environments often involves precise click targets
• Con: Users with mobility impairments may have difficulty using input devices such as motion controllers
• Con: Users with mobility impairments may have difficulty using head trackers to adjust roll, pitch and yaw
• Con: Users with severe mobility impairments may find locomotion, such as walking or flying, difficult
• Con: Users may have difficulty sensing haptic cues

Mobility Use Cases

• As a user with a mobility impairment, I need to be able to adjust time limits, so I can complete tasks.
• As a user with a mobility impairment, I need to use multiple input devices, so that I can interact with the environment.
• As a user with a mobility impairment, I need a focus indicator, so I can identify which element has focus.

Hearing

• Pro: To date VR has focussed mainly on the visual aspects of virtual reality
• Con: Some virtual experiences rely heavily on audible cues to guide users
• Con: Bluetooth latency impacts upon the ability of users to perceive visual and audio events synchronously
• Con: Users may not be able to communicate using voice chat
• Con: Audio dialog requires captions
• Con: Sign language is not supported

Hearing Use Cases

• As a user with a hearing impairment, I need to be able to turn off ambient soundscapes, so I can hear interface elements such as clicks, bleeps and transitions.
• As a user with a hearing impairment, I need visual or haptic equivalents of aural interfaces, so I can interact with interface elements.
• As a user who hears better in one ear, I need to be able to control the location of spatialized audio, so I can hear interface elements.
• As a user with a hearing impairment, I need captions of dialog, so I can read what is being said.

Cognition

• Pro: If given training and time to learn, users with cognitive impairments can become proficient in virtual environments ¹
• Pro: The vividness and synchronous interaction of virtual environments can allow users to focus their attention more effectively
• Pro: Can allow users with Asperger's Syndrome to learn social skills that might be difficult to grasp in real life ¹
• Pro: Students who need more training and time can usually replicate learning artefacts and interactions
• Pro: Virtual environments can be designed to support error-free training, which can assist cognitive disorders ⁷
• Pro: The distratction offered by Immersive Virtual Reality (IVR) has the potential to diminish pain perception amongst chronic and acute pain sufferers ⁸
• Con: The user interface may be difficult to learn
• Con: Virtual world skills may be difficult to acquire
• Con: Input devices such as wands, joysticks and 3D mice may be difficult to master ⁷
• Con: Some users may experience vertigo
• Con: Users may suffer from motion sickness, due to conflicts between sensory cues or between the virtual environment and what is felt be the body ⁷
• Con: Users may experience disturbed motor skills after using virtual environments, due to a lag in readaptation to the real world environment ⁷
• Con: Flashing or moving objects may cause seizures or migraines ¹

Cognition Use Cases

• As a user with a photosensitive seizure disorder, I need to avoid three flashes in a second, so I do not have a seizure.
• As a user with a cognitive impairment, I need training and time, so that I can learn the environment.
• As a user with a disability, I need suggestions on how to fix input errors, so I can easily correct mistakes.

Low Vision

• Pro: Voice chat can be useful
• Con: Users may have difficulty identifying objects
• Con: Users may have difficulty perceiving events
• Con: Users need to be able to change the text size of the interface and chat windows
• Con: Users may have trouble reading text which lacks sufficient contrast against the background

Low Vision Use Cases

• As a user with low vision, I need to be able to increase text size, so I can read without a screen magnifier.
• As a user with low vision, I need to have sufficient contrast between text and the background, so I can read the text.

Blindness

• Pro: Haptic feedback an alternate means of feedback to users
• Pro: Organisations such as the Web3D Consortium are trying to develop open standards, such as X3D, so that 3D web-based graphics can be intergrated with HTML
• Pro: Mobility and orientation activities in virtual environments can transer to real environments ⁴
• Pro: Sensory substitution devices (SSDs), such as vitual canes and visual to music converters, can be used to aid virtual mobility and perception of shapes and colors ⁴
• Con: Most content of virtual environments is heavily visual
• Con: VR platforms are not designed to work with screen readers such as JAWS or NVDA
• Con: Don't use the usual accessibility APIs
• Con: There is no accepted metadata standard virtual worlds
• Con: Developers do not have access to information for understanding the needs of vision impaired users, or accepted techniques for resolving issues
• Con: Whilst many of the use cases for VR are similar to the web, there are no accessibility guidelines such as alternative text and meta information for objects

Blindness Use Cases

• As a user with no vision, I need verbal descriptions of interactions, objects and locations, so I can navigate.

Olfactory

• Pro: For the most part, users who have difficulty perceiving odours will have little difficutly interacting with virtual environments
• Pro: Many olfactory cues, such as the smell of a burning pot in a cooking activity, can be represented visually, e.g. smoke coming from a pot
• Con: Smell is likely to be an important part of Immersive Virtual Reality (IVR)

Olfactory Use Cases

• As a user who cannot who has difficulty perceiving odours, I need a visual equivalents, so I can perceive olfactory events.

Older Users

• Pro: Rehabilitation activities for stroke in virtual environments can translate to real world outcomes ⁷
• Pro: Gaming features in virtual environments can enhance motivation of stroke sufferers undergoing therapy
• Pro: VR lends itself to home based rehabilitation

Use Cases of Older Users

• As an older user I need training and time, so that I can learn the environment.