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Cali Fidopiastis

Publications and source records attributed to Cali Fidopiastis.

2 recordsLinked to original sources

Albertian errors in head-mounted displays: I. Choice of eye-point location for a near- or far-field task visualization.

A theoretical investigation of rendered depth and angular errors, or Albertian errors, linked to natural eye movements in binocular head-mounted displays (HMDs) is presented for three possible eye-point locations: the center of the entrance pupil, the nodal point, and the center of rotation of the eye. A numerical quantification was conducted for both the pupil and the center of rotation of the eye under the assumption that the user will operate solely in either the near field under an associated instrumentation setting or the far field under a different setting. Under these conditions, the eyes are taken to gaze in the plane of the stereoscopic images. Across conditions, results show that the center of the entrance pupil minimizes rendered angular errors, while the center of rotation minimizes rendered position errors. Significantly, this investigation quantifies that under proper setting of the HMD and correct choice of the eye points, rendered depth and angular errors can be brought to be either negligible or within specification of even the most stringent applications in performance of tasks in either the near field or the far field.

Computer Simulation↗

An adaptive driver and real-time deformation algorithm for visualization of high-density lung models.

Technological advances in Augmented Reality (AR) and extraction of 3D patient specific medical data led to the creation of medical visualization using AR environments, in which the 3D data is registered and synchronized with the position of the patient. One of the challenges in such visualization environments is maintaining an accurate shape of the 3D data for self-deformable models such as lungs. An accurate deformation of lung model with 3D visualization may significantly increase the teaching and diagnosing ability of physicians. Modeling the deformation of lungs primarily involves the accurate representation of Pressure-volume relationship and the hysteresis in the relationship during inhalation and exhalation. This paper explains a real-time physiologically accurate deformation algorithm and its hardware rendering. We then introduce a novel approach for the representation of accurate pressure volume relationship based on an analogy with classical mechanics. Our simulation results show that the hysteresis obtained is more accurate as compared to current lung models. Thus in our approach a physically realistic deformation of lung model is obtained by the integration of the accurate PV relationship with real-time deformation method.

Algorithms↗