Motion segmentation and estimation through the determination of spatio-temporal primitives in an image sequence

This paper describes a motion estimation scheme front image sequences, which consists of three main stages : local processing, intermediate-level structuring, optic flow field estimation . The first stage is concerned with either the determination of spatiotemporal edges along with their local spatial direction in the image plane and the component of their associated velocity vector perpendicular to this direction, or the segmentation into regions according to motion-based hierarchically performed criteria which take into account an explicit partial motion information . Both designed algorithms utilize principles of local modeling and likely hypothesis testing. Concerning the first one, the defined likelihood ratio test is implemented according to some appropriate mask convolution, the complexity order of which is similar to conventional spatial gradient computation . The purpose of the second stage is to obtain a structured partition of the image, resulting front edge linking and/or region segmentation . Thfienall stage deals with the velocity field estimation, that-is-to-say the reconstruction of the second component of displacement vectors by combining local observations. First, a recursive stochastic gradient, used to achieve the minimization of some simple functional, enables to estimate optic flow along contours . Then, the estimation within delineated domains is considered . Our approach is in particular distinguished by treating beforehand potential discontinuities of the velocity field in the image . Moreover, it provides with a set of intermediate-level spatio-temporal primitives .Schéma d'estimation du mouvement dans des séquences d'images s'articulant en 3 étapes fondamentales: traitement local, structuration intermédiaire, estimation du champ des vitesse

The Crewman's Associate for Path Control (CAPC): an automated driving function

Army Tank Automotive Command, Warren, Mich.http://deepblue.lib.umich.edu/bitstream/2027.42/1134/2/88210.0001.001.pd

Underwater Vehicles

For the latest twenty to thirty years, a significant number of AUVs has been created for the solving of wide spectrum of scientific and applied tasks of ocean development and research. For the short time period the AUVs have shown the efficiency at performance of complex search and inspection works and opened a number of new important applications. Initially the information about AUVs had mainly review-advertising character but now more attention is paid to practical achievements, problems and systems technologies. AUVs are losing their prototype status and have become a fully operational, reliable and effective tool and modern multi-purpose AUVs represent the new class of underwater robotic objects with inherent tasks and practical applications, particular features of technology, systems structure and functional properties