Abstract: The invention relates to a structure for positioning an object in a three-dimensional coordinate system.The object of the invention is to obtain a structure making it possible to orient an object in space without displacing its center of gravity.This object is achieved with the aid of a structure incorporating a support (5), at least five slings (7, 9, 11, 13, 27) for suspending the object (1) on said support (5) and means (33) for regulating the length of each sling.This structure more particularly makes it possible to position a tactical missile with an anechoic or dead room.

Abstract: For training persons having to fire missiles from the shoulder, a simulator is proposed which comprises a simulated launch or firing tube (10), which carries a front, releasable or jettisonable mass (12) and a rear releasable or jettisonable mass (14) at its ends. These masses are held by electromagnets (34, 36). When the person firing or firer presses the trigger (18), the rear mass (14) is ejected to the left followed, with a time lag (.DELTA.t), by the front mass (12). Thus, the load relief and site and bearing movements felt by the firer during a real launch are restored.

Abstract: A system for the transmission of digital data in packets comprising transmission and reception means, wherein:the transmission means are able to form single words taken in a group of words each having 2n bits and constituted by a word M of n bits between which are inserted the n bits of the complement word M, the bits of M being displaced relative to those of M by a number p of ranks, the choice of p defining a single word of the group;in the reception means there is only one single word detector and it functions with n bits, said detector being able to detect the displaced appearances of p ranks of words M and M on each bit sequence of even rank and uneven rank.