The contribution to spatial awareness of adding a roll degree-of-freedom (DOF) to telepresence camera platform yaw and pitch was examined in an experiment where subjects judged direction and rotation of stationary target markers in a remote scene. Subjects viewed the scene via head-slaved camera images in a head-mounted display. Elimination of the roll DOF affected rotation judgment, but only a...

BACKGROUND AND PURPOSE Variability in patient head positioning may yield substantial interstudy image variance in the clinical setting. We describe and test three-step technologist and computer-automated algorithms designed to image the brain in a standard reference system and reduce variance. METHODS Triple oblique axial images obtained parallel to the Talairach anterior commissure (AC)-post...

Deviations of the subjective visual vertical in the roll or fronto-parallel plane occur commonly in disorders of the brainstem and have been extensively explored. In contrast, little is known about deviations in other directions. The present retrospective study focused on deviations in the pitch (sagittal) direction in 176 patients with a wide variety of disorders. The test task was to set a se...

In order to study the dynamic behavior of ships navigating in severe environmental conditions it is imperative to develop their governing equations of motion taking into account the inherent nonlinearity of large-amplitude ship motion. The purpose of this paper is to present the coupled nonlinear equations of motion in heave, roll, and pitch based on physical grounds. The ingredients of the for...

In three rhesus monkeys three-dimensional eye positions were measured with the dual search coil technique. Recordings of spontaneous eye movements were made in the light and in the dark, with the monkeys in different static roll or pitch positions. Eye positions were expressed as rotation vectors. In all static positions eye rotation vectors were confined to a plane, i.e. Listing's plane was co...

Attitude control systems for autonomous underwater vehicles are often implemented with separate controllers for pitch motion in the vertical plane and yaw motion in the horizontal plane. We propose a novel time-varying model for a streamlined autonomous underwater vehicle that explicitly displays the coupling between yaw and pitch motion due to nonzero roll angle and/or roll rate. The model fac...

This paper explores the feasibility of roll–pitch–yaw integrated autopilots for a high angle-of-attack missile. Investigation of the aerodynamic characteristics indicates strong cross-coupling effects between the motions in longitudinal and lateral directions. Robust control techniques based on H1 synthesis are employed to design roll– pitch–yaw integrated autopilots. The performance of the pro...

The position of the trunk can be negatively influenced by many diseases. Several methods can be used for identifying defects in balance and coordination as a result of pathology of the musculoskeletal or nervous system. The aim of this article is to examine the relationship between the three methods used for analysis of trunk sway and compare two fundamentally different MoCap systems. We used a...

OBJECTIVES The concept of natural head position (NHP) was first introduced by Broca in 1862, and was described as a person's stable physiologic position "when a man is standing and his visual axis is horizontal." NHP has been used routinely for clinical examination; however, a patient's head position is random during cone-beam computed tomography (CBCT) acquisition. To solve this problem, we de...