Computing three-dimensional eye position quaternions and eye velocity from search coil signals.

نویسندگان

  • D Tweed
  • W Cadera
  • T Vilis
چکیده

The four-component rotational operators called quaternions, which represent eye rotations in terms of their axes and angles, have several advantages over other representations of eye position (such as Fick coordinates): they provide easy computations, symmetry, a simple form for Listing's law, and useful three-dimensional plots of eye movements. In this paper we present algorithms for computing eye position quaternions and eye angular velocity (not the derivative of position in three dimensions) from two search coils (not necessarily orthogonal) on one eye in two or three magnetic fields, and for locating primary position using quaternions. We show how differentiation of eye position signals yields poor estimates of all three components of eye velocity.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Implications of rotational kinematics for the oculomotor system in three dimensions.

1. This paper develops three-dimensional models for the vestibuloocular reflex (VOR) and the internal feedback loop of the saccadic system. The models differ qualitatively from previous, one-dimensional versions, because the commutative algebra used in previous models does not apply to the three-dimensional rotations of the eye. 2. The hypothesis that eye position signals are generated by an ey...

متن کامل

Mathematics of three-dimensional eye rotations

The recording of three-dimensional eye position has become the accepted standard in oculomotor research. In this paper we review the mathematics underlying the representation of three-dimensional eye movements. Rotation matrices, rotation vectors and quaternions are presented, and their relations described. The connection between search coils and rotation matrices is explained, as well as the c...

متن کامل

Recording three-dimensional eye movements: scleral search coils versus video oculography.

PURPOSE This study compared the performance of a video-based infrared three-dimensional eye tracker device (Chronos) with the scleral search coil method. METHODS Three-dimensional eye movements were measured simultaneously with both systems during fixation, saccades, optokinetic stimulation, and vestibular stimulation. RESULTS Comparison of fixation positions between -15 degrees and +15 deg...

متن کامل

Three Dimensional Analysis of Caloric Nystagmus and Effect of Visual Suppression in Cats

Background and Objectives:The caloric test is considered to be one of the most sensitive parameters in the diagnosis of peripheral vestibular disorders, although it can test only the function of the lateral semicircular canals. In this study, the authors measured the eye movements and visual suppression of caloric nystagmus in cats three dimensionally using a magnetic search coil system. Materi...

متن کامل

Three-dimensional kinematics of saccadic and pursuit eye movements in humans: Relationship between Donders’ and Listing’s laws

For Listing's law to be obeyed during eye movements, the "half-angle rule" must be satisfied: the eye velocity axis must tilt away from Listing's plane by half the angle of eye position eccentricity from primary position. We aimed to determine if this rule is satisfied during horizontal and vertical pursuit compared with saccades. Three-dimensional (3-d) eye rotation data were acquired from fiv...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Vision research

دوره 30 1  شماره 

صفحات  -

تاریخ انتشار 1990