Leonardis D.,PERCRO Laboratory |
Frisoli A.,PERCRO Laboratory |
Barsotti M.,PERCRO Laboratory |
Carrozzino M.,PERCRO Laboratory |
Bergamasco M.,PERCRO Laboratory
Presence: Teleoperators and Virtual Environments | Year: 2014
This study investigates how the sense of embodiment in virtual environments can be enhanced by multisensory feedback related to body movements. In particular, we analyze the effect of combined vestibular and proprioceptive afferent signals on the perceived embodiment within an immersive walking scenario. These feedback signals were applied by means of a motion platform and by tendon vibration of lower limbs, evoking illusory leg movements. Vestibular and proprioceptive feedback were provided congruently with a rich virtual scenario reconstructing a real city, rendered on a head-mounted display (HMD). The sense of embodiment was evaluated through both self-reported questionnaires and physiological measurements in two experimental conditions: with all active sensory feedback (highly embodied condition), and with visual feedback only. Participants’ self-reports show that the addition of both vestibular and proprioceptive feedback increases the sense of embodiment and the individual’s feeling of presence associated with the walking experience. Furthermore, the embodiment condition significantly increased the measured galvanic skin response and respiration rate. The obtained results suggest that vestibular and proprioceptive feedback can improve the participant’s sense of embodiment in the virtual experience. © 2014 by the Massachusetts Institute of Technology.
Berselli G.,University of Modena and Reggio Emilia |
Parvari Rad F.,University of Bologna |
Vertechy R.,Percro Laboratory |
Parenti Castelli V.,University of Modena and Reggio Emilia
2013 IEEE/ASME International Conference on Advanced Intelligent Mechatronics: Mechatronics for Human Wellbeing, AIM 2013 | Year: 2013
In this paper, a quantitative comparison is made between straight beam and curved beam flexures for application on selectively compliant mechanisms. Following a general procedure previously described in the literature, the closed-form compliance equations for both flexural hinges are firstly derived. Then, the two morphologies are compared in terms of maximum achievable rotation and selective compliance (i.e. capability of providing low stiffness along a single desired direction). In particular, the performance of each design solution is quantified by means of purposely defined quality indexes, analytically computed on the basis of the hinges compliance matrix. Finally, the potentials of these types of flexures for the optimal design of compliant robotic fingers are critically discussed. © 2013 IEEE.
Borner H.,TU Munich |
Endo S.,TU Munich |
Frisoli A.,PERCRO Laboratory |
Hirche S.,TU Munich
IEEE World Haptics Conference, WHC 2015 | Year: 2015
While research has demonstrated how vibrotactile devices can be effectively used to guide human behavior, efficient mappings of vibration patterns for spatial guidance in time-critical dynamical tasks have not yet been understood. In this paper, we contrast two types of action-dependent, haptic stimulus designs to demonstrate the different effects of vibrotactile feedback on the human control performance. A wireless bracelet is used to provide patterns of vibrotactile stimuli in real-time, representing either optimal hand velocity or acceleration for the stabilization of an inverted pendulum. The optimal control behavior is supplied by a linear quadratic regulator. The analyses of the participants' stabilization and learning behavior revealed a significant improvement caused by the additional velocity-dependent feedback. The results are consistent with previous research, which indicates that the human sensory-motor system is generally more sensitive to velocity than acceleration information. In summary, the present paper suggests how human-centric vibrotactile stimuli should be designed and how they can be effectively transmitted to the human user for time-critical behavioral guidance. © 2015 IEEE.