%0 Journal Article
%T Virtual Sectioning and Haptic Exploration of Volumetric Shapes in the Absence of Visual Feedback
%A Tatiana V. Evreinova
%A Grigori Evreinov
%A Roope Raisamo
%J Advances in Human-Computer Interaction
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/740324
%X The reduced behavior for exploration of volumetric data based on the virtual sectioning concept was compared with the free scanning at the use of the StickGrip linkage-free haptic device. Profiles of the virtual surface were simulated through the penholder displacements in relation to the pen tip of the stylus. One or two geometric shapes (cylinder, trapezoidal prism, ball, and torus) or their halves and the ripple surface were explored in the absence of visual feedback. In the free scanning, the person physically moved the stylus. In the parallel scanning, cross-sectional profiles were generated automatically starting from the location indicated by the stylus. Analysis of the performance of 18 subjects demonstrated that the new haptic visualization and exploration technique allowed to create accurate mental images, to recognize and identify virtual shapes. The mean number of errors was about 2.5% in the free scanning mode and 1.9% and 1.5% in the parallel scanning mode at the playback velocity of 28£żmm/s and 42£żmm/s, respectively. All participants agreed that the haptic visualization of the 3D virtual surface presented as the cross-sectional slices of the workspace was robust and easy to use. The method was developed for visualization of spatially distributed data collected by sensors. 1. Introduction Even in the absence of direct contact and visual feedback, people have to explore physical properties such as friction and roughness, compliance and stiffness of environment (in geophysics and monitoring), and materials (nondestructive testing). Complementing visual information, the existing haptic shape-rendering algorithms focus on rendering the interaction between the tip of a haptic probe and the virtual surface. Using haptic interface and analyzing the effects of different types of the force feedback, the operator of the hand-held detector can feel the change of roughness, rigidity, and other physical properties of a contact. However, human perception of spatially distributed data, for example, the surface topography with varying stiffness, relying on single-point-based exploration techniques often fails to provide a realistic feeling of the complex topological 3D surfaces and intersections [1¨C7]. Although manual palpation can be very effective, free scanning with a single-point inspection is unnatural and significantly increases the cognitive load to establish the right relations between successive samples of sensory information separated in space and time [8]. Haptic recognition and identification of spatial objects, their unique shape, and
%U http://www.hindawi.com/journals/ahci/2013/740324/