Haptic Sphere vs Haptic Cone. Comparison of the
two haptic guides (sphere and cone) give means 46.44
and 69.66 with std (14.18, 12.74) respectively, having
ANOVA result as significant.
The analysis of task completion time can be seen in
the figure 6, where
1: spherical guide(no haptic) + stereo display
2: spherical haptic guide + stereo display
3: Conical guide(no haptic) + stereo display
4: Conical haptic guide + stereo display
4.3.2 Subjective Evaluation
In this section we analyze the users’ responses and
comments collected through questionnaire. Summa-
rizing the response we observed that both visual and
haptic guides provide assistance to users in objects’
selection but they preferred haptic guides because of
their active nature. The spherical guide enabled them
to complete the task in lesser time as compared to the
conical one because it restricted the users to make se-
lection from a single direction for the sake of preci-
sion.
Figure 6: Task completion time & level of guidance under
various conditions.
5 CONCLUSIONS
In order to remove the inconveniences observed in
Follow-Me, we proposed haptic guides which not only
provide active guidance (attractive force toward the
object) to the user to select an object but also physi-
cally restricts his/her hand’s movement whenever re-
quired. We implemented two versions of haptic guide.
The spherical haptic guide that provides assistance in
object selection from all directions. The second is
a conical haptic guide which impart guidance when
the object selection is required from a specific direc-
tion. Here the guide not only gives attractive force
towards the object but also resist the exit of virtual
pointer through the walls of the cone. Two groups,
each composed of 10 young volunteers performed the
task to evaluate the haptic guides.
We observed for both types of haptic guides a reduc-
tion in task’s completion time, especially for the con-
ical haptic guide. It was also noted that task’s com-
pletion time increased in case of conical haptic guide
as compared to the spherical haptic guide.
Evaluating the subjective responses collected through
questionnaire, both the groups reported that haptic
guides provided them significant guidance in object
selection, made the task easier and thus resulted in
increasing performance. Another important point is
that SPIDAR can be successfully used in large scale
virtual environment not only to have free movements
(without force) in the environment but also to gener-
ate realistic forces if required.
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