On scaling strategies for the full-body postural control of virtual mannequins

Abstract

a b s t r a c tDue to its intrinsic complexity, full-body postural input has been mostly limited to off-line motion capture and to on-line puppetry of a virtual character with little interaction with its environment (e.g. floor). The motion capture technology is now mature enough to envision the on-line full-body postural control of virtual mannequins involved in precise reaching tasks. We have investigated such tasks for mannequins of differing body heights in comparison to that of the system user. Such broad-range avatar control is relevant for virtual prototyping in various industrial sectors as a single person is responsible for evaluating a virtual prototype for a full range of potential end-users. In the present paper we report on two scaling strategies that can be enforced in such a context of height-differing avatar control. Both scaling strategies have been evaluated in a wide-range reach study both in front of a stationary immersive display and with an HMD. A comparison is also made with a baseline scenario, which exploits a simple rigid shape (i.e. a proxy), to assess the specific influence of controlling a complex articulated avatar.

Characterizing embodied interaction in First and Third Person Perspective viewpoints

“…Similarly, more experimentation would be necessary to compare our results with reaching behavior in reality. Using appropriate perspectives could for instance compensate for the known limitations of VR for reaching [3], throwing [4] or other natural interaction movements. Evaluating the transfer of skill from VR training to the real situation would in turn provide information on the benefit of providing subjects with a feedback on their body and their surrounding (such as in 3PP).…”

“…In VR, the usage of orthogonal third person viewpoints has been explored and was for instance recommended to help setting the posture of a motion controlled virtual body [3]. The use of 3PP is also recommended to compensate for the compression of distance perception inherent to immersion systems such as large stereoscopic projection.…”

“…the experienced location of the self. From a more practical standpoint, changing the perspective from first (1PP) to third person perspective (3PP) allows taking a new and potentially more informative point of view within a VR application (such as for training [3,17,4]). The problem is that 3PP breaks the natural condition in which subjects experience self-location with respect to their real bodies, and might consequently lower the sense of embodiment and the sense of presence.…”

Integrated Analytic and Linearized Inverse Kinematics for Precise Full Body Interactions

“…However, even now few motion capture hardware and software can provide a robust and precise real-time participant registration with virtual objects and obstacles. The problem is made even more complex whenever the participant wishes to feel immersed as a virtual counterpart with a differing body size as analyzed in [BMT09]. We believe that methods and algorithms tackling such precision issues will find their way in the game sector in the near future.…”

Immersive singularity-free full-body interactions with reduced marker set

“…However, even now few motion capture hardware and software can provide a robust and precise real‐time participant registration with virtual objects and obstacles. The problem is even more complex as evaluating a virtual prototype requires to impersonate a wide range of virtual mannequins with differing body characteristics representative of a population distribution 3. An additional mapping stage is necessary to handle proportion differences between the user input motion and the controlled target entity 4, 5.…”