Abstract: The invention relates to a process and device for regulating at any instant the speed of a mobile member, such as a pulley, moving in a stroke of determined uniform direction, by employing a fluid passing under pressure through an orifice of restricted section. According to the invention, said pressurized fluid is made to pass several times alternately in one direction and in the other through said orifice, during said stroke of determined uniform direction. The invention is more particularly applicable to the deployment of appendices mounted on board space vessels.

Abstract: A method and a device for suspending and driving into oscillation a space telescope oscillating mirror connected to a support whereby angular motions of the oscillating mirror around an oscillation axis are controlled from an auxiliary mass which is adapted to oscillate around said oscillation axis, and potential energy is momentaneously stored, for example in elastic form, when said oscillating mirror and said auxiliary mass come close in opposed phase to respective extreme angular positions. These oscillating mirror and auxiliary mass are preferably connected to the common support through flexible rods bound to said support. Dynamic oscillations in the support are thus minimized so as to allow precise observation in two neighboring directions, particularly for celestial scanning.