Here are some principles to follow as you develop your own AR safety patterns to make your applications street-smart.
The user’s risk decreases as they are further from a hazard: safety patterns should reflect to this varying risk. With this responsiveness, users would be more inclined to pay attention when they do get activated. They also feel more organic, reflecting the fluidity and extreme fidelity of our physical environment.
One feature of immersive environments such as augmented reality is that users can be looking in any direction. As you develop street-smart patterns, keep in mind that users may not always be looking in the direction you’d like them to look. Your patterns may have to combine different strategies for catching the users’ attention at various orientations.
Humans experience a gap between the moment they notice an alert, and the moment they are able to react to it. Designers of roads and street signs are familiar with this perception-reaction time.
In our tests, AR users demonstrated a similar delayed reaction to AR safety patterns, or did not initially notice safety patterns when they were activated. While this can be partially mitigated with increasing the eye-catching nature of your patterns, it can be just as effective to allow users the buffer time and space to divert their attention from what they are focused on towards the safety pattern. This generally means surfacing the safety pattern early in the buffer zone (i.e. having a generous Detection Buffer).
Safety UI pattern should be eye-catching but should avoid unnecessary obscuring of the environment. This could frustrate or disorient the user.
For example, when designing a safety pattern, consider which aspects of that pattern need to be persistent versus those that can be just momentary. An AR barrier could be persistent to clearly delineate the buffer, but a highlight of a part of the ground could be momentary.
Consider alerting the user’s other senses to catch their attention. Audio and haptic cues could be useful as well to alert users that they have strayed into the buffer zone.
The audio cues could be designed to be coherent with the form of the AR pattern. Consider a glowing fence that fades into view. The corresponding audio cue could resemble the fizzle of an energy beam.
Users come from all kinds of different backgrounds, speak different languages, . They may have mobility-impairment, vision-impairment, color-blindness, and other forms of disabilities.
To address a wide audience, strive for indicators that are understandable by as many people as possible. This could mean minimizing reliance on copy, using instead colors, motion, form or other elements to alert the user. Consider color contrasts that can be detected by color-blind individuals. These are just a few recommendations: refer to the A11y project for more thorough guidelines on Universal Design.