%O Report 
%F Marchand94b
%A Marchand, E.
%A Rutten, E.
%A Chaumette, F.
%T Applying the synchronous approach for real time active visual reconstruction
%N 875
%I IRISA
%X In this paper, we apply the synchronous approach to real time active visual reconstruction. It illustrates the adequateness of signal, a synchronous data flow programming language and environment, for the specification of a system dealing with various domains such as robot control, computer vision and programmation of hierarchical parallel automaton. More precisely, one application consists in the 3D structure estimation of a set of geometrical primitives using an active vision paradigm. At the level of camera motion control, the visual servoing approach (a closed loop with respect to vision data) is specified and implemented in Signal as a function from sensor inputs to control outputs. Furthermore, the 3D reconstruction method is based on the ``structure from controlled motion'' approach (constraining camera motion for optimal estimation). Its specification is made in parallel to visual servoing, and involves the delay mechanism of signal for the specification of filters. This reconstruction involves focusing on each object; we thus present a perception strategy for connecting up several estimations, using tasks hierarchies interruption and time intervals in signal. The integration of these techniques is validated experimentally by their implementation on a robotic cell, from which we present experimental results
%U ftp://ftp.irisa.fr/techreports/1994/PI-875.ps.gz
%8 October
%D 1994