Abstract：
:A method is proposed to determine the rigid structure as well as the three dimensional motion of an object from a sequence of orthographically projected images. It is assumed that the velocities as well as the positions of the points attached to the object are observable in the images. The "instantaneous rigidity condition" wich states that the relative position vector between any two points is orthogonal to the corresponding relative velocity vector is derived from the condition of rigidity. Assuming further that the rotational velocity component is constant throughout the period of observation, each of the projected relative velocity vectors is shown to move along one of the elliptical trajectories, all of which are similar to one another. The orientations of the longer axes are common to every trajectory. Then one can determine the equations of the ellipses by observing only two points in three views or three points in two views. The solution is obtained from a set of linear equations. The length of the longer axis enables one to determine the relative velocity. The instantaneous rigidity condition is then used to obtain the relative position. The special cases where the rotational axis is either perpendicular to or parallel with the image plane are discussed. The above results are discussed in relation to the relevant psychophysical observations as well as theoretical studies.
journal_name
Biol Cybernjournal_title
Biological cyberneticsauthors
Sugie N,Inagaki Hdoi
10.1007/BF00335200subject
Has Abstractpub_date
1984-01-01 00:00:00pages
431-6issue
6eissn
0340-1200issn
1432-0770journal_volume
50pub_type
杂志文章abstract：:Diffusion processes have been extensively used to describe membrane potential behavior. In this approach the interspike interval has a theoretical counterpart in the first-passage-time of the diffusion model employed. Since the mathematical complexity of the first-passage-time problem increases with attempts to make t...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00201480
更新日期：1995-10-01 00:00:00
abstract：:Within the field of motor control, there is no consensus on which kinematic and kinetic aspects of movements are planned or controlled. Perturbing goal-directed movements is a frequently used tool to answer this question. To be able to draw conclusions about motor control from kinematic responses to perturbations, a m...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-012-0505-7
更新日期：2012-10-01 00:00:00
abstract：:We present a procedure that optimally adjusts specified parameters of a mathematical model to describe a set of measured data. The technique integrates a dynamic systems-simulation language with a robust algorithm for nonlinear parameter estimation, and it can be implemented on a microcomputer. Sensitivity functions a...
journal_title：Biological cybernetics
pub_type： 杂志文章,评审
doi：10.1007/BF00201441
更新日期：1990-01-01 00:00:00
abstract：:Highly-interconnected networks of nonlinear analog neurons are shown to be extremely effective in computing. The networks can rapidly provide a collectively-computed solution (a digital output) to a problem on the basis of analog input information. The problems to be solved must be formulated in terms of desired optim...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00339943
更新日期：1985-01-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00203135
更新日期：1992-01-01 00:00:00
abstract：:The peripheral auditory system of lizards has been extensively studied, because of its remarkable directionality. In this paper, we review the research that has been performed on this system using a biorobotic approach. The various robotic implementations developed to date, both wheeled and legged, of the auditory mod...
journal_title：Biological cybernetics
pub_type： 杂志文章,评审
doi：10.1007/s00422-016-0701-y
更新日期：2016-10-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00204123
更新日期：1989-01-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-002-0341-2
更新日期：2002-10-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-003-0422-x
更新日期：2003-09-01 00:00:00
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pub_type： 杂志文章
doi：10.1007/s00422-005-0583-x
更新日期：2005-07-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00201423
更新日期：1995-08-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00202786
更新日期：1995-01-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00197609
更新日期：1994-01-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-004-0535-x
更新日期：2005-03-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00335157
更新日期：1981-01-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章,评审
doi：10.1007/s004220050293
更新日期：1996-09-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF02414887
更新日期：1992-01-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-005-0584-9
更新日期：2005-07-01 00:00:00
abstract：:The ability to locomote is a defining characteristic of all animals. Yet, all but the most trivial forms of navigation are poorly understood. Here we report and discuss the analytical results of an in-depth study of a simple navigation problem. In principle, there are two strategies for navigating a straight course. O...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-008-0251-z
更新日期：2008-09-01 00:00:00
abstract：:Statistical properties of spike trains as well as other neurophysiological data suggest a number of mathematical models of neurons. These models range from entirely descriptive ones to those deduced from the properties of the real neurons. One of them, the diffusion leaky integrate-and-fire neuronal model, which is ba...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-016-0690-x
更新日期：2016-06-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-014-0626-2
更新日期：2014-10-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00336922
更新日期：1985-01-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-007-0159-z
更新日期：2007-08-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00319980
更新日期：1982-01-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-018-0770-1
更新日期：2018-10-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s004220050422
更新日期：1998-02-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00320482
更新日期：1986-01-01 00:00:00
abstract：:Two-dimensional scalar fields (e. g. pictures) are often described by way of a linear superposition of simple base functions. It is argued that such decompositions are often unnatural in the sense that the decomposition takes no regard of the structure of the field and it may happen that the parts are more complicated...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00337293
更新日期：1979-08-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-006-0064-x
更新日期：2006-07-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00198096
更新日期：1990-01-01 00:00:00
