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M. W˛ asowicz
6 Haptics
Apart from visual and acoustic stimuli, people experience their environments through
other modalities, such as motor input [28]. In terms of perception of action, motor
input has been recognized as crucial for wayfinding and navigation [14]. Research
on goal-directed neural mechanism showed that visuals do not have to accurately
resemble real-world environment to be effective, with a fair level of abstraction and
only medium visual detail being enough for a virtual environment to represent its reallife counterpart [29]. In addition, visual flow has been proven to affect perceptual
processes [8]. Human movements can be simulated manually by using an output
device such as gamepad, or alternatively through physical movements within a visual
display setting or on a treadmill [5].
Systems interfacing with the sense of touch and force are called haptic systems.
Virtual reality systems incorporating haptic systems have greater potential in simulating real-world than do those without them. Haptic devices serve two functions:
sensing human manipulation, and simulating force signals from the virtual environment and exerting these forces on the user’s body; the latter function is called
actuation [30]. VR systems exploit the following haptic devices: exoskeletons and
stationary devices; gloves and wearable devices; point-sources and specific task
devices; and locomotive interfaces. Feedback devices are also developed, including
feedback input devices, force feedback devices, and tactile displays [25]. Thanks to
the development of such systems, contemporary VR systems make it possible to simulate object manipulation, motion, and force control tasks, such as grasping, touching
and walking. Full-body motion tracking makes it possible to represent avatars of both
the observer and other people in the virtual environment, thus allowing for visual
feedback of self-movements and multi-user interactions [12]. As was the case with
the simulation of sounds, these devices still call for additional development, in order
to improve their quality.
In terms of touch-to-touch sensory substitution, most devices provide a simple
feedback of vibration. This is because it is difficult to obtain haptic technology
that is convincing in terms of simulating touch. It is a far more sensitive faculty
than both sight and sound because it requires a sensation to be updated as many as
1000 times per second or more, in order to relay a convincing tactile experience.
Feedback data of an object’s surface geometry or texture can be provided by tactile
feedback systems or tactile displays. While haptic interfaces simulate the shape,
weight, or compliance of an object, tactile interfaces simulate the object’s surface
texture. The sensations of contact are generated to the skin, which is capable of
responding to several types of physical sensation: vibrations, small-scale shape or
pressure distribution, and temperature sensations. State-of-the-art systems generate
combinations of these sensations [25].
Haptic sensations acquired through virtual interaction simulate the corresponding
interaction between the human and the real environment, but given the sensitivity of
human skin and body in general, the virtual feeling is extremely difficult to imitate
given today’s technology. Virtual environment comparability research, specifically
M. W˛ asowicz
6 Haptics
Apart from visual and acoustic stimuli, people experience their environments through
other modalities, such as motor input [28]. In terms of perception of action, motor
input has been recognized as crucial for wayfinding and navigation [14]. Research
on goal-directed neural mechanism showed that visuals do not have to accurately
resemble real-world environment to be effective, with a fair level of abstraction and
only medium visual detail being enough for a virtual environment to represent its reallife counterpart [29]. In addition, visual flow has been proven to affect perceptual
processes [8]. Human movements can be simulated manually by using an output
device such as gamepad, or alternatively through physical movements within a visual
display setting or on a treadmill [5].
Systems interfacing with the sense of touch and force are called haptic systems.
Virtual reality systems incorporating haptic systems have greater potential in simulating real-world than do those without them. Haptic devices serve two functions:
sensing human manipulation, and simulating force signals from the virtual environment and exerting these forces on the user’s body; the latter function is called
actuation [30]. VR systems exploit the following haptic devices: exoskeletons and
stationary devices; gloves and wearable devices; point-sources and specific task
devices; and locomotive interfaces. Feedback devices are also developed, including
feedback input devices, force feedback devices, and tactile displays [25]. Thanks to
the development of such systems, contemporary VR systems make it possible to simulate object manipulation, motion, and force control tasks, such as grasping, touching
and walking. Full-body motion tracking makes it possible to represent avatars of both
the observer and other people in the virtual environment, thus allowing for visual
feedback of self-movements and multi-user interactions [12]. As was the case with
the simulation of sounds, these devices still call for additional development, in order
to improve their quality.
In terms of touch-to-touch sensory substitution, most devices provide a simple
feedback of vibration. This is because it is difficult to obtain haptic technology
that is convincing in terms of simulating touch. It is a far more sensitive faculty
than both sight and sound because it requires a sensation to be updated as many as
1000 times per second or more, in order to relay a convincing tactile experience.
Feedback data of an object’s surface geometry or texture can be provided by tactile
feedback systems or tactile displays. While haptic interfaces simulate the shape,
weight, or compliance of an object, tactile interfaces simulate the object’s surface
texture. The sensations of contact are generated to the skin, which is capable of
responding to several types of physical sensation: vibrations, small-scale shape or
pressure distribution, and temperature sensations. State-of-the-art systems generate
combinations of these sensations [25].
Haptic sensations acquired through virtual interaction simulate the corresponding
interaction between the human and the real environment, but given the sensitivity of
human skin and body in general, the virtual feeling is extremely difficult to imitate
given today’s technology. Virtual environment comparability research, specifically