hello everyone my name is Daniel Medeiros from the University of Glasgow and I'm here
to present our paper um about passive haptics and perception manipulation and constrained spaces
so people are using VR in their daily lives going instead of more controlled environments they are
using VR in places that are more less control like their home that the virtual environment that needs
to adapt to it so they're home or their office or even in public spaces one interesting use is in
passenger environment since people really pass a lot of time in these environments but one of
the problem is that they have very limited space uh said this constraints need to be
addressed or reappropriated to improve the way people interact with XR one way people use to
use of VR to improve the way people interact is by using passive haptic surface such as walls or
even stimulating people's muscles to really feel that they are touching their virtual object but
in the the one good thing about this constrained environment is to have surfaces all around you
so you basically can calibrate virtual objects on top of these surfaces that you basically make
people feel that you're touching really a virtual object but you're really touching
a physical object so it's part of you have a lot of services such as horizontal surfaces such as
tray tables or even seat bags are present in most of different environments but also you
have to take into account the social context so these different surfaces have a lot of different
things that it needs to be addressed so one of the problems is that the passive has improved
the feeling of presence but surface may be located in uncomfortable positions for a head and hands
it needs to be addressed so we basically uh did ask to do the study to ask two different questions
so how the surface type in case passive haptic surfaces impacts performance and user preferences
in VR and also how the surface orientation impacts performance and user preferences so we in our user
study we had two levels one was surface type where you had passive haptics and two forms of different
um mid-air surfaces with SNAP where people can kind of go through a surface and without snap
the people can go through a surface and also orientations such as horizontal and vertical
so we had real um plain seeds where we basically had cardboard to hide the indentation so people
feel that more like a planar surface which so basically like a tray table and easy
the test that we chose was uh modified fitzlaw task
where you had basically two subtasks one is the reaching test where you they reach for a sphere
that was calibrated um according to the center of the plane where they basically had to reach
for this and then reach for the surface this was one of the subtasks and the next one really needed
to drag between tasks and the surface so we use quantitative metrics such as throughput with a
uh a test metric for performance a path length time precision and we separated these between
the 3D component which is the reaching and the 2D component which is the dragging also we collected
some user preferences through questionnaires such as satisfaction task workload Visual Comfort arm
exertion embodiment which is the how people feel connected to the virtual environment and
also we conducted semi-structure interview for more granular data so we got any results
we found that the passive haptic significantly reduced breaching and dragging times and had the
highest throughput and the shortest path length and also improved their sense people's sense
of embodiment and in terms of mid-air we found that the mid-air with SNAP increased Precision
according to the other one but they had a negative effect of embodiment especially the self-location
because they had to do exaggerated movements to take the hands out of the surface for example
and the mid-air also will had overall more fatigue due to the lack of surface to rest yarn
and in terms of uh surface orientation we had less definitive results for example the
vertical had shorter time but were less precise but when we talk ask people about that in the
qualitative interview people preferred the horizontal due to family reality because it
kind of looks more like a tablet and they they felt that it felt it was more on their space
uh they they also said it was a list a little bit less fatiguing for my hand but in long-term use
it it way it led to more neck fatigue so users preferred a vertical for long-term fatigue like
in in in the case of these we found that we need to one way to overcome these type of problems is
to use perception manipulation to try and render these objects in a more comfortable way it's not
just for the hand but also for the neck one way is to use perception manipulation is which is
done by manipulating what the person is seeing and virtual reality while they do a different action
in real life one way is use haptic retargeting for example where the user uh before the environment
is rotated so the user feels that they're touching multiple cues but in the end they're just you
reaching for one single Cube another one is the redirected walking where people it's actually
seen as they're walking in a in in circles in real life but they're really walking the straight path
but how and normally these uh cases are imperceptual manipulations but in our case due to
the limitation in the space of the environment we have to use perception and manipulation to alter
the virtual space in a perceptible way to increase false comfort and also social acceptability so we
divide the second user study to remap users movement and also the virtual environment
movement to be rendered in more comfortable positions for both the arms and the neck
so for example for the vertical surfaces we employed for translational remapping to remap
the user's movement and the virtual environment to be in a more comfortable position for both
the arms and the neck and in the case of horizontal surfaces we use translational
plus rotational remapping to render them in more comfortable positions for the element
so in the horizontal space is remapping you use different four different ones where we rotated
the the surface and the person's movements to basically like to less extreme rotations and also
like accordingly to the the position accordingly to the to the eyes of the person so do from 45
60 75s and 90 degrees and we added baselines for this and here we show a video of the different
ones so the vertical remapping we see that the process is looking straight ahead whilst
reaching for a surface the horizontal 45 or you have the rotated 45 degrees and the person is
n is in between the person's head and the surface six degrees which is a similar one
75 again this is a more extreme one
and finally 90 degrees
and we see that in this case there are bridging doing a vertical movement but that their movements
are mapped in a vertical way uh we use also like the same type of metrics but included an
extra one and neck fatigue and our results we found the remapped conditions performed
better than Baseline conditions both vertical and horizontal and also less extreme remappings uh the
45 and 60 were preferred to the trade-off between workload comfort and improved Precision compared
to baselines and also notice an increase workload on more extreme rotations the horizontal 75 and
90 and also decreased embodiment scores we now also notice an increased workload on the vertical
remap condition due to the closed mismatch between real and virtual movements so people actually try
to match their where their hands were So based on that we devised three guidelines based on the use
of perception manipulation and passive haptics um so the first one is to appropriate nearby physical
surfaces the second one is use moderate perception remapping to maintain performance and improve
comfort and when remapping vertical surfaces consider the proximity of real and virtual hands
and for more information please read the info paper and thank you