Accession Number : ADP001205

Title :   Kinematics of Image Flows,


Personal Author(s) : Waxman,Allen M.

Report Date : JUN 1983

Pagination or Media Count : 7

Abstract : This study concerns a new formulation and method for solution of the image flow problem. It is relevant to the maneuvering of a robotic system through an environment containing other moving objects and/or terrain. The tow-dimensional image flow is generated by the relative rigid body motion of a smooth, textured object along the line of sight to a monocular camera. By analyzing this evolving image sequence, one hopes to extract the instantaneous motion (described by six degrees of freedom) and local structure (slopes and curvatures) of the object along the line of sight. The formulation relates a new local representation of an image flow to object motion and structure by twelve nonlinear, algebraic equations. The representation parameters, termed observables, are given by the two components of image velocity, three components of rate-of-strain, spin, and six independent image gradients of rate-of-strain and spin, evaluated at the point on the line of sight. This representation is motivated by the deformation of a finite element of flowing continuum. A method for solving these equations was devised and successfully implemented on a VAX-750 computer. A number of examples were explored revealing two classes of ambiguous scenes (i.e., nonunique solutions are obtained). A sensitivity analysis was also begun in order to estimate noise levels in the representation parameters which still yield acceptable solutions. Estimates of computing time required for this approach to image flow analysis indicate that real-time implementation is not out of the question. (Author)

Descriptors :   *Image processing, *Kinematics, *Two dimensional flow, *Nonlinear algebraic equations, Robotics, Visual perception, Degrees of freedom, Transformations, Problem solving, Gradients, Cameras, Real time, Installation, Motion, Finite element analysis, Slope, Curvature, Line of sight

Distribution Statement : APPROVED FOR PUBLIC RELEASE