Touch screens are becoming the increasingly dominant input device in everything from automated teller machines (ATMs), ticket-vending machines, control monitors in vehicles, and of course on smart phones and tablets and table-type computers. Their iconic approach to buttons and switches that are driven by software rather than the physical nature of a conventional keyboard, mouse or switches means that applications can be adapted to countless layouts and formats. But, there is a big disadvantage to touch screens that simply cannot be avoided – you have to be able to see the screen to use it effectively.
The issue of hand to eye coordination may be one simply of familiarity for most users and tapping and swiping a flat screen generally becomes second nature, albeit potentially more distracting for machine operators and drivers who ought to keep their visual concentration on the job in hand rather than the screen. But for people with problems with their sight, touch screens have the potential to exclude them from the digital age. This is, of course, the point at which developers begin to talk about haptics.
Haptics refers to the sense of touch. It’s what old-fashioned keyboards have in spades but touchscreens lack. Reintroducing the tactile feedback of a keyboard or other conventionally haptic technology seems at first to be a retrograde step, but for the visually impaired or for people with problems with their dexterity, it could reinvigorate the modern computer interface and re-engage those people who are insidiously being disenfranchised by our urge to go smooth…
There are already some touch screen devices that have haptic interactivity. Vibrating screens give the impression of touching “real” buttons, for instance. While gaming consoles often come with motorized components to jolt gripping trigger fingers and such to simulate real sporting sensations. Hiroaki Nishino of Oita University and colleagues there and at Kyushu Island Alliance of ICT, AVOC Co Ltd, and the Institute for Hypernetwork Society, have developed guidelines for developers and manufacturers hoping to market haptic, or tactile, interfaces for their devices based on their experiments with different systems and vibrating stimulus patterns of different types.
They conclude that there are three primary considerations:
- create a set of tactile effects by combining stimuli with different activation time length
- create the effects with strong stimuli
- create the effects by combining a set of patterns with different vibration strength.
The team tested their system in experiments in an exhibition-type environment and invited various people of different ages, gender and occupation to try the system as they believe it will be useful for the general public as well for elderly and vision-impaired people.
“A touch screen interface design with tactile feedback for practical applications” in Int. J. Space-Based and Situated Computing, 2013, 3, 8-21