Method and apparatus for controlling the attitude of a satellite in space by thruster reaction forces without loss of thruster fluid into space. A jet of gas, preferably compressed air, comprising reaction mass stored in a reservoir on board, is discharged in a predetermined direction into an endless enclosed evacuated volume. The molecules of discharged gas are scavenged from the volume and recompressed and restored to the reservoir. The discharged gas is scavenged sufficiently rapidly from the...

The attitude of a spacecraft can be effectively controlled in three axes using the combination of a gravity gradient boom and three electromagnets. The electromagnets are controlled according to a control law that takes into consideration signals from a magnetometer and a signal indicating the orbital angular velocity of the spacecraft. During the acquisition phase of the flight, the gravity gradient boom is not extended and electromagnets are operated according to a control law that only takes ...

A mechanism with one foot pedal for controlling the fore-and-aft attitude of a high-speed boat having the usual cavitation or trim plate. When the foot pedal is depressed the cavitation plate is lowered through an interconnecting assembly of pivoted members to lower the bow of the boat against any upending tendency as it accelerates from a dead stop in the water. As the boat speed increases, release of pressure on the foot pedal causes movement of the cavitation plate to an upper position, where...

A multi-element piezo-electric transducer is mounted on the wall or frame of a body and is held in a predetermined position relative to the body. The support element of the transducer is subjected to an altering force by the force applying element of the transducer which applied such force when the attitude of the body changes. The altering force is transmitted to the piezo-electric element of the transducer by way of the support element. The altering force bends or otherwise deforms the piezo-e...

An effective vehicle attitude control method in which the abrupt change of the vehicle attitude due to the acceleration slip control can be quickly controlled. When the slippage of a drive wheel is determined to be greater than a predetermined value, the drive force of the drive wheel is controlled and, at the same time, the suspension characteristic is altered to a harder state. For preferentially keeping maneuverability and riding comfort, the altered suspension characteristic may be restored ...

An attitude control system using magnetic torquing is enhanced using a momentum wheel which is pivoted if the sensed error signal about the roll axis exceeds a given threshold. The momentum wheel is pivoted under control of a stepping motor through a first angle proportional to the detected average roll error, and one-half nutation period later through an equal angle in the same direction. Alternatively, the momentum wheel is pivoted over first and second angles of different values wherein the d...

Disclosed is a valve having a body having an inlet channel, an outlet channel in fluid communication with the inlet channel, and a flow-monitoring region situated medially between the inlet and outlet channels. Further provided within the body is a secondary channel having a first end and a second end, the first end in fluid communication with the inlet side of the flow-monitoring region and the second end extending to the outside of the body. The first end of the secondary channel is provided w...

An attitude control system for satellites includes a sensor (10) for generating output signals in response to variations in the attitude of the satellite. These signals are applied to a Kalman filter (12) which models the dynamic state of the satellite and instructs an attitude controller (13) to generate control signals for controlling the actuators. The system is responsive to the actual physical performance of the actuators to provide feed back to the modelling circuit.

A pressure and attitude responsive valve comprises a resilient substantially cylindrical hollow valve body having an opening in one end to receive a pressurized fluid to be regulated. The opposite valve body end is closed by a frusto-conical end wall having a central opening therein. A valve ball, larger than the opening but smaller than the valve body bore, is disposed within the valve body to open or close the opening depending on the attitude of the valve body. Longitudinal slits in the wall ...

A system for measuring the attitude of the platform that is movable relative to a fixed frame. The system comprises at least three platform mounting assemblies, each of the three mounting assemblies comprising (a) an isolation mount interconnecting the platform to the frame, the isolation mount permitting the platform to move relative to the frame, and (b) a means for measuring the movement of a point on the platform relative to the frame along three orthogonal axes. For each of the three mounti...