Simulation of conditions met by extraterrestrial satellites

Abstract

Abstract 1,027,017. Apparatus for testing satellites. ELECTRONIQUE MARCEL DASSAULT. Aug. 13, 1964 [June 9, 1964], No. 33065/64. Heading F3A. [Also in Divisions E2 and G3] Apparatus in which a body 20 is suspended under conditions which simulate the behaviour of an artificial satellite comprises a support rotatable about a vertical axis, the body being suspended from the support along the axis of rotation, and a device providing a mutual feedback control of the rotary movements of the body and its support about their common axis. The suspension means is selected to have the lowest possible resistance to torsion and a high resistance to stresses perpendicular to the vertical axis. The body 20 is suspended from a framework 24 by an elongated member 22, the framework being supported by a rotatable plate 40 within an evacuated chamber 51 provided with observation windows 52. The member 22 may consist of three steel strips, Fig. 3, symmetrically arranged and a similar member 25 may connect the body 20 to the base of the framework 24. Light from a source S, simulating a star, is received within the body 20 through a telescope L and a mirror 35 reflects light to a collimating telescope 36 mounted on the framework 24. Within the body 20 is a fly wheel driven electrically to control the orienta tion of the satellite in response to external signals. The mounting plate 40 is fixed to the rotor 44 of a reversible electric motor M. The apparatus may be used to test the alignment of telescope L with a light source or to test pneumatic means for directing the satellite. In testing the behaviour of the flywheel 21, a signal is transmitted to start the wheel 21 rotating, and light reflected from the mirror 35 to the telescope 36 is transmitted to a device 49, which then transmits a signal to an amplifier 47 proportional to the resultant torque on the body 20 produced by the flywheel. Amplifier 47 feeds the signal to start the motor M, which then rotates the plate 40 in a direction to restore the satellite to the zero position. The sensitivity of the telescope 36 determines the instant at which the restoring motion of plate 40 is started and this is dependent upon the suspension of the body 20. By transmitting a signal to the motor M through a circuit 50, the framework may be rotated and the effect on the body 20 observed through the windows 52. A thrust-bearing which aligns the axis in the vertical position comprises a stationary part 60 surrounding a movable part 69. Within the part 60 is an annular duct 68 filled with compressed air at constant pressure and communicating through channels 66, 67 with recesses 61 beneath plate 40 and recesses 64 adjacent the part 69. Thus as the pressure rises in recesses 61 the plate is pushed upwards and if the part 69 tilts consequent rise in pressure in a recess 64 restores the part 69 to the vertical.

Inventors

No inventors recorded.

Bibliographic Details