The document discusses various haptic feedback techniques for virtual reality experiences. It describes active haptics which use computer-controlled devices to provide tactile or force feedback, and passive haptics which use physical props registered to virtual objects. Haptic retargeting techniques are introduced to allow one physical prop to represent multiple virtual objects, including body warping, world warping, and hybrid warping. Body warping shifts the rendering of the user's body to align with props. World warping manipulates the virtual world's coordinates. Hybrid warping combines both techniques. Examples from Microsoft Research demonstrate haptic retargeting illusions using a single physical cube mapped to different virtual cubes. The document concludes by discussing potential applications of these
2. What do Haptics mean?
Simply, touch feedbacks that
provides a satisfying sence of
presence in virtual reality.
3. It’s time to …
touch it!
We’ve seen virtual reality
4. Touch In IVEs
A virtual hand penetrates a
virtual object because there is
no real object to touch.
Experiences such as the one
indicated in the figure destroy
the illusion upon which the
usefulness of VEs depends.
5. Haptic Feedback Solutions
There are two broad classes of haptic
feedback solutions in VEs:
1. active-haptic feedback (or active
haptics)
2. passive-haptic feedback (or
passive haptics)
6. Active Haptics
Active haptics are computer
controlled devices that supply
tactile or force feedback to the
user through electric, electronic, or
mechanical means.
Example: In the case of Robotic
Shape Displays, a robotic arm
places a real object correctly in
front of the user’s hand
7. Passive Haptics
physical props to which virtual objects are
registered
traditionally, for every virtual object to be
touched, there must be an analogous physical
prop.
That is, traditional passive haptics use a one-
to-one mapping between real and virtual
objects
8. Passive Haptics (Cont.)
Limitation:
an entire real-world infrastructure would need
to be built and changed whenever a virtual
scene is changed
Solution:
Haptic Retargeting
i.e. Mapping need not be one to one
9. Haptic Retargeting (HR)
Definition:
reusing the passive haptics of the same real
physical objects across multiple virtual
objects.
This can be generalized to finding a mapping
between the virtual and real coordinate
systems.
10. Mapping requirements
1. The mapping is dynamic; i.e. the solution
should support interactive manipulations and
not require careful placement of objects or
pre-computed solutions.
2. The mapping is minimally noticeable (or
unnoticeable) and therefore minimally
disturbing to the person.
11. Techniques For HR Solution
There are three approaches:
I. Body Warping(a.k.a. hapic hand)
II. World Warping(a.k.a. redirected passive haptics)
III. Hybrid Warping(both World and Body manipulation)
13. Body Warping Example
consider a simple arrangement:
a real cube A positioned on the desk in front of the user
and the virtual cube A′ shifted slightly to the right.
to ensure that the virtual hand meets the real cube, a
translation to the right must be applied
Shift the entire rendering of the body to the right
14. Place your screenshot here
Microsoft Research
Dynamic Repurposing of
Passive Haptics, Minecraft
Game
15. Top-down view of setup with
Kinect (green), Oculus HMD (blue) and Oculus DK2 Camera (red).
16. Arrangement of cubes
Left: before the demonstration task begins
Right: two cubes removed once the HMD is put on
In each phase, pressing a button initiates a new trial,
mapping the single physical cube to one of the three virtual
cubes using Body Warping.
17.
18. Place your screenshot here
Body Warping
(a) causes hand to drift
away from expected body
position
(b) with a body-friendly
warp, alignment can be
achieved without
drastically separating hand
from body.
19. 1 for 3 Illusion!
Body Warping
Microsoft Research
Minecraft Project
21. “
World Warping Means …
Manipulating the virtual world’s
coordinate system.
i.e. Moving the virtual world to align
different virtual objects in turn with the
same real object.
22. Place your screenshot here
Ring of Cubes Illusion!
Progressively maps a single
physical cube to different
virtual cubes arranged in
an arc around the button,
and within the user’s reach.
25. Hybrid Warping
Combines Body and World Warping
such that :
1. head motions activate World
Warping
2. hand motions activate Body
Warping
26. 1. The real cube first aligned with the green cube (left)
2. Moving towards the red cube with World Warping
while the user looks around (middle)
3. The alignment is completed with Body Warping as
they reach for it (right).
36. References
[1] M. Azmandian, M. Hancock, H. Benko, E. Ofek, A. Wilson, Haptic Retargeting:
Dynamic Repurposing of Passive Haptics for Enhanced Virtual Reality Experiences,
Microsoft Research, SIGCHI, 2016
[2] L. Kohli, Redirected Touching, Doctoral Dissertation, Frederick P. Brooks, The
University of North Carolina at Chapel Hill, NC, USA, 2013
[3] T. Narumi, K. Matsumoto, Y. Ban, Y. Yanase, T. Tanikawa, M. Hirose, Unlimited
corridor: redirected walking techniques using visuo haptic interaction, ACM SIGGRAPH
2016 Emerging Technologies, The University of Tokyo, 2016
[4] “How VR could have you walking in circles in future without knowing it,” [Online].
Available: https://techcrunch.com/2016/08/05/. [Accessed 17 May 2017]
[5] F. Steinicke ; G. Bruder ; L. Kohli ; J. Jerald ; K. Hinrichs, Taxonomy and
Implementation of Redirection Techniques for Ubiquitous Passive Haptic Feedback,
Cyberworlds, 2008 International Conference, Hangzhou, China, IEEE, January 2009
