초록 ▼

A spacecraft according to the invention includes a pair of propellant tanks, with the nominal center of mass of the spacecraft located therebetween. Propellant is coupled from the tanks to a velocity-change-inducing thruster by a controllable coupling arrangement. Unwanted torques may occur which te

A spacecraft according to the invention includes a pair of propellant tanks, with the nominal center of mass of the spacecraft located therebetween. Propellant is coupled from the tanks to a velocity-change-inducing thruster by a controllable coupling arrangement. Unwanted torques may occur which tend to perturb the attitude. An attitude control arrangement generates an error signal in response to deviations of the attitude from the desired attitude. The error signal is processed to control the propellant coupling arrangement, to cause propellant to be used preferentially from at least one of the tanks in a manner which tends to move the actual center of mass relative to the axis of thrust or line of action of the thruster. In one embodiment of the invention, the controllable coupling arrangement includes a manifold for coupling propellant from the tanks to the thruster, a tank of pressurizing gas, and a controllable manifold coupling the tank of pressurizing gas to the propellant tanks. The attitude error signal is processed to control the pressurant gas pressure in the propellant tanks, to thereby tend to feed preferentially from one tank to the thruster, to thereby move the center of mass toward (or sometimes away from) the axis of thrust of the thruster.

대표청구항 ▼

[ What is claimed is:] [1.] A spacecraft, comprising:a three-axis stabilized body;first and second spaced-apart propellant tanks, with the nominal center of mass of said body and propellant tanks therebetween;a first thruster coupled to said body, and having its axis of thrust passing through said n

[ What is claimed is:] [1.] A spacecraft, comprising:a three-axis stabilized body;first and second spaced-apart propellant tanks, with the nominal center of mass of said body and propellant tanks therebetween;a first thruster coupled to said body, and having its axis of thrust passing through said nominal center of mass;a load of propellant in said propellant tanks, with a distribution which may, in conjunction with other portions of said body of said spacecraft, cause the location of the actual center of mass to deviate from said nominal center of mass;propellant coupling means coupled to said propellant tanks and to said first thruster, for supplying propellant to said first thruster from said propellant tanks during operation of said thruster, whereby said operation may result in torques which perturb the attitude of said spacecraft, which, if an attitude control thruster is provided, may require energization of said attitude control thruster for maintaining said attitude;attitude sensing means coupled to said body for sensing deviation of said attitude from a desired attitude for generating signals indicative of said deviation; andcontrol means coupled to said attitude sensing means and to said propellant coupling means, for controlling said propellant coupling means in response to said error signals, only during operation of said first thruster, in a manner which preferentially feeds propellant from one of said first and second tanks to said first thruster in a manner which tends to move said actual center of mass relative to said axis of thrust in a manner which tends to maintain said attitude.