Abstract: A method is provided for stabilizing an orientation and height of a person or load-carrying multicopter with a plurality of motors, wherein the drive of the individual motors in flight is continuously calculated by a flight control unit and correspondingly prescribed to the motors using control technology, for which purpose, based on a desired torque ?, of a desired thrust s preferably prescribed by a pilot signal, and of a motor matrix M, the drive of the motors is calculated by a motor allocation algorithm f and provided as a control signal to the motors, wherein the following applies to the drive and the corresponding motor control variables u: u=f(?, s, M).

Abstract: A flight control system that is adapted for controlling movements of a rotary wing aircraft while considering passenger discomfort, to a rotary wing aircraft with such a flight control system, and to a method of operating a flight control system. The flight control system includes sensors configured to generate sensor data based on captured motions of the rotary wing aircraft, motion actuators that are adapted for inducing a translational and/or a rotational movement of the rotary wing aircraft about at least one of a yaw axis, a roll axis, or a pitch axis, and a passenger discomfort-aware control unit that is configured to generate, based on the sensor data, passenger discomfort-aware actuator control signals for controlling the motion actuators of the rotary wing aircraft.

Abstract: A method is provided for stabilizing an orientation and height of a person or load-carrying multicopter with a plurality of motors, wherein the drive of the individual motors in flight is continuously calculated by a flight control unit and correspondingly prescribed to the motors using control technology, for which purpose, based on a desired torque ?, of a desired thrust s preferably prescribed by a pilot signal, and of a motor matrix M, the drive of the motors is calculated by a motor allocation algorithm f and provided as a control signal to the motors, wherein the following applies to the drive and the corresponding manipulated motor variables u: u=f(?, s, M).

Abstract: In a process for discharging a test mass that is free-floating in a surrounding electrode casing on board a satellite, the electrode casing is enclosed by a vacuum tank, and has one or more first electrodes for the application of electrostatic forces and/or moments to the test mass. In addition, the electrode casing also has one or more second electrodes for modulating alternating voltages (particularly, high frequency voltages) for measuring purposes onto the test mass as well as one or more light-emitting elements, which irradiate the test mass, the electrode casing and/or the electrodes particularly with ultraviolet light for generating a photoelectric effect. Automatically and iteratively, a test mass charge of the test mass is determined. A control operation for eliminating the determined test mass charge is carried out until the test mass charge has reached a defined target value.

Abstract: In a process for discharging a test mass that is free-floating in a surrounding electrode casing on board a satellite, the electrode casing is enclosed by a vacuum tank, and has one or more first electrodes for the application of electrostatic forces and/or moments to the test mass. In addition, the electrode casing also has one or more second electrodes for modulating alternating voltages (particularly, high frequency voltages) for measuring purposes onto the test mass as well as one or more light-emitting elements, which irradiate the test mass, the electrode casing and/or the electrodes particularly with ultraviolet light for generating a photoelectric effect. Automatically and iteratively, a test mass charge of the test mass is determined. A control operation for eliminating the determined test mass charge is carried out until the test mass charge has reached a defined target value.

Abstract: A three-axis attitude control for a low-orbiting satellite. A sensor which measures in two axes is a magnetometer, and a satellite is positioned on an inclined orbit at an inclination angle of approximately 25 degrees to approx. 90 degrees. The satellite has been provided with an overall spin by spin wheels, and actuators generate torque on all three axes of the satellite. Accordingly, this is applicable to three-axis attitude control of a low-orbiting satellite that includes a sensor which measures in two axes and that includes one or several spin wheels.

Abstract: A method of determining the position of geostationary satellites by means of signals of at least one navigation satellite. A determination is made of data concerning the transit times of the signals from the at least one navigation satellite to the geostationary satellite by a device of the geostationary satellite, and a determination is made of navigation data of the at least one navigation satellite by an independent navigation device. A determination is made of data concerning the system time of the at least one navigation satellite by an independent navigation device, and a data exchange occurs between the geostationary satellite and the navigation device in order to determine position data of the geostationary satellite from the transit times, the navigation data as well as the system time of the at least one navigation satellite.

Abstract: Described is a device for determining the attitude on board of a satellite (1) with a data transfer device for carrying out optical data exchange between at least two satellites (1, 3); a device for determining one's own attitude; a device for determining the directional vectors in an inertial co-ordinate system from one's own attitude and from attitude data of at least two satellites (1, 3), said attitude data having been transmitted by means of the data transmission device; a device for determining the directional vector directed to the satellites (1, 3) of which there are at least two, in a fixed-body co-ordinate system of the satellite; and a device for attitude determination from the directional vectors determined. Also described is a method for carrying out attitude determination.

Abstract: A method of determining the position of geostationary satellites by means of signals of at least one navigation satellite. A determination is made of data concerning the transit times of the signals from the at least one navigation satellite to the geostationary satellite by a device of the geostationary satellite, and a determination is made of navigation data of the at least one navigation satellite by an independent navigation device. A determination is made of data concerning the system time of the at least one navigation satellite by an independent navigation device, and a data exchange occurs between the geostationary satellite and the navigation device in order to determine position data of the geostationary satellite from the transit times, the navigation data as well as the system time of the at least one navigation satellite.

Abstract: The invention provides GPS navigational system for a satellite in space which comprises a front end section having an input for receiving GPS signals from a plurality of satellites, a digital preprocessor connected to the front end section for digitally preprocessing the GPS signals received from the front end section, and a signal processor connected to the digital preprocessor for decoding the GPS signals to determine a position of the satellite. An on-board computer is provided and a first data bus line connects the data processor and the signal processor for bi-directional data exchange therebetween and a second data bus line connects the signal processor and the on-board computer for bi-directional data exchange therebetween.

Abstract: An attitude controller for a 3-axis stabilized, Earth oriented bias momentum spacecraft is described, where only 2-axis attitude measurements from the Earth sensor are available. In contrast to the classical spacecrafts that are controlled w.r.t. a fixed orbital Earth pointing reference frame, (possibly large angle) time varying reference signals are considered here, i.e. the control task consists of a tracking problem. The controller design consists of a decoupling controller and axis-related PID controllers based on yaw observer estimates.

Abstract: A system for autonomous on-board determination of the position of an earth orbiting satellite consists of a biaxially measuring earth sensor which defines the z-axis (yaw axis) of the satellite and of several biaxially measuring sun sensor measuring heads which are arranged on the satellite structure such that, with the exception of earth shadow phases, they supply a direction vector measurement. Out-of-plane movement of the satellite is propagated by means of a precise model of the satellite dynamics including natural disturbance forces and thrusts during maneuvers on board. In order to compensate sensor uncertainties and the effects of thermal deformations, the satellite orbit is precisely measured at regular intervals (approximately 3 months), and by means of this information, a calibration function (time function for a day) for compensating measured values is determined.

Abstract: A low earth orbiting satellite control arrangement according to the invention has an earth sensor for measuring roll and pitch of the satellite relative to an earth oriented moving reference system, a spin wheel mounted along an axis perpendicular to the orbital plane of the satellite for measuring spin of the satellite, and two magnet coils for generating control. A first of the two magnet coils is aligned substantially in parallel to a roll axis of the satellite, and the second is aligned substantially parallel to the yaw axis. Alternative control algorithms are disclosed for controlling attitude, nutation and spin of the satellite based on information from the earth sensor, spin wheel and an observer which is also mounted on the satellite.

Abstract: The sun search method for a satellite stabilized in three axes according to the invention uses a sun sensor device with a visual field possibly containing gaps, and a rotational speed gyro which measures in a measuring axis that is oriented arbitrarily. A regulating law with the form .tau.=-kGG.sup.T .omega. is used (.tau.=regulating torque, k=amplification factor, G=directional vector of measuring axis of rotational speed gyro, .omega.=rotational speed vector of the satellite). A rotational wheel momentum H which is not parallel to the measuring axis, is generated with the aid of an additional flywheel device.

Abstract: A method and apparatus for steering a low-earth-orbit communication satellite requiring sun-orientation for solar-power accumulation is disclosed. Momentum-bias both maintains nadir pointing and adds yaw-steering moments for sun-trackig attitude control, simultaneously. The method has two principal steps: 1) open-loop momentum decoupling, for correcting the calculated steering torque, and closed-loop attitude compensation, to correct for perturbations about the calculated attitude in accordance with one of two control law definitions. This combines the advantage of stable gyroscopic attitude control with those of open-loop yaw steering.

Abstract: A measurement arrangement is useful for controlling the attitude of a three-axis stabilized satellite equipped with sun-sensors for determining the orientation of the sun (sun vector) with respect to a satellite-fixed coordinate system, as well as with speed gyroscopes for detecting components of the satellite speed of rotation vector .omega.. It is necessary that the measurement range of the sun-sensors cover the round angle in a preselectable plane (for example XY plane) and perpendicularly thereto a limited angular range of maximum .+-..alpha..sub.2max on both sides of the plane. In addition, only an integrating speed gyroscope carrying out measurements in a single measurement axis that encloses with the plane an angle of at least (.pi./2)-.alpha..sub.2max should be provided.

Abstract: A three-axis stabilized, earth-oriented satellite has an attitude control system with regulators, actuators, an earth sensor that carries out measurements along two axes and a sun-sensor arrangement that also carries out measurements along two axes. The field of view of the sun-sensor arrangement covers the round angle on a plane of the satellite-fixed coordinate system. Only the sun-sensor arrangement and the earth sensor act as measurement transducers. A sun and earth acquisition process for such a satellite has the following steps: seeking the sun; setting the sun vector in a first direction of reference; setting the speed of rotation of the satellite around the sun vector at a constant value; setting the sun vector in a second direction of reference, so that by rotating the satellite around the latter the optical axis of the earth sensor sweeps over the earth; and picking up the earth. Special regulating rules are disclosed.