Computing three-dimensional eye position quaternions and eye velocity from search coil signals.
نویسندگان
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.
منابع مشابه
Implications of rotational kinematics for the oculomotor system in three dimensions.
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ورودعنوان ژورنال:
- Vision research
دوره 30 1 شماره
صفحات -
تاریخ انتشار 1990