RU2736522C1 - Method of orientation of spacecraft - Google Patents

Abstract

FIELD: astronautics.

SUBSTANCE: invention relates to control of orientation of spacecrafts (SC) with solar panels (SP). Method includes orientation of the SC relative to the direction to the Sun using an additional autonomous control circuit (ACC) connected in violation of the said SC orientation. SP is fixed relative to the housing SC. When entering the shadow section of the orbit from the serviceable on-board computer (OBC), the maximum duration of this section is started. After exiting from the shadow section in case of OBC fault by the timer signal, the SC is switched to the ACC mode, and if the OBC is OK, the timer is switched off. Timer is started from pulse signal of terminator or according to information from OBC. At fixed SP for their orientation to Sun SC is introduced into passive spin mode. At negative energy balance in case of loss of SP orientation to the Sun, economical mode of accumulator batteries operation is used.

EFFECT: technical result is high reliability and survivability of SC with provision of stable power supply during the whole period of SC active existence.

1 cl, 1 dwg

Description

Appointment

The invention relates to the field of space technology and can be used on spacecraft (SC) to ensure orientation to the Sun during abnormal operation of the SC.

State of the art

Spacecraft control includes, first of all, spacecraft attitude control to obtain the required position of the spacecraft body relative to external landmarks (control of the spacecraft rotational motion around the center of mass).

After launching the spacecraft into orbit, the control of the angular position in order to orient the spacecraft instruments to the objects under study becomes the main flight mode (see V.N.Vasiliev. Spacecraft attitude control systems, M., 2009, pp. 10-11), therefore, the most important task of modern space technology is the improvement of the attitude system, which allows for a long time to determine with high accuracy the direction of the spacecraft axes relative to the axes of a certain coordinate system, i.e. the angular position of the spacecraft, as well as its angular velocity.

There is a method and device for controlling the motion of a spacecraft with a controlled attitude (patent, RF, No. 2669481), which consists in automatic compensation of errors of the strapdown attitude control system included in the attitude control system of the spacecraft caused by systematic errors in the angular velocity sensor unit, in comparison with the readings of the angular velocity sensor unit. speed and a block of star sensors in error correction devices, in generating signals for correcting systematic errors of a block of angular velocity sensors, in processing them in a microcomputer, in controlling a microcomputer by executive bodies, to provide them with an appropriate mechanical effect on the spacecraft body in yaw, roll and pitch, which differs by orienting the spacecraft in a given orbit with the aid of a spacecraft orientation device containing a solar sensor and a three-dimensional magnetometer or an infrared vertical sensor, the solar batteries are automatically set according to the solar sensor in a fixed position relative but the spacecraft hulls, to obtain their maximum illumination, guaranteeing a positive energy balance in the event of any malfunctions in the operation of the attitude control system, including failures in the operation of the central computer, control the solar array attitude control device from the ground control center according to rigid logic in case of failures, include and the block of star sensors is turned off to control the spacecraft attitude according to a given controlled algorithm and according to control commands from the ground control center.

The main disadvantage of this method is that it does not take into account the failure of the central computer when the spacecraft passes the shadow area, which affects its survivability. So, if during normal operation of the spacecraft during the passage of the shadow section, a malfunction occurs in the operation of the central computer ("hovering"), then there will be no information about the end of the shadow section and the spacecraft will not go into operation using an autonomous control loop (control of the orientation of solar batteries according to rigid logic).

There is a known method of orientation of a spacecraft (patent, RF, No. 2706743), taken as a prototype of the invention, including the orientation of the spacecraft relative to the direction to the Sun and the Earth using an on-board computer according to information from sensors for determining the angular position, orientation of the spacecraft relative to the direction to the Sun using an additional an autonomous control loop connected to control in case of violation of the orientation of the spacecraft relative to the direction to the Sun, with the appropriate installation of solar batteries not rigidly fixed to the spacecraft body in a fixed position relative to the spacecraft body; when controlling the spacecraft using a serviceable on-board computer, upon entering the shadow section, a timer is started, provided in the control unit of the spacecraft, with a duration equal to the maximum duration of the shadow section; after leaving the shadow area with a faulty on-board computer, according to the timer signal, the spacecraft is switched to operation mode using an autonomous control loop, and with a working on-board computer, according to information from the on-board ballistic software, the timer is turned off, and the spacecraft is controlled according to the information from a working on-board computer ...

The main disadvantage of the prototype is that if the on-board computer is faulty, the timer with a duration equal to the maximum duration of the shadow section does not start when entering the shadow section due to the fact that the shadow parameters (start and end times) for each loop are calculated using the on-board ballistic software on-board computer. As a result, the spacecraft loses its orientation to the Sun and Earth, which can lead to the failure of the spacecraft.

In addition, in the prototype with a faulty on-board computer and a negative energy balance of the power supply system, measures are not provided for choosing a rational mode that increases the resource of its operation, and there is also no optimization of the method for orienting solar batteries, the panels of which are rigidly fixed to the case in modern spacecraft.

The purpose of the proposed method of orientation of the spacecraft is to increase the reliability and survivability of the spacecraft during its long-term autonomous operation in space.

Disclosure of invention

The proposed method of orientation of the spacecraft consists in the fact that the spacecraft is oriented relative to the direction to the Sun and the Earth using the on-board computer according to the information from the sensors for determining the angular position, the orientation of the spacecraft relative to the direction to the Sun using an additional autonomous control loop connected to control in case of disorientation the spacecraft relative to the direction to the Sun, with the corresponding installation of solar panels in a fixed position relative to the spacecraft body; when controlling the spacecraft using a working on-board computer, when entering the "shadow" interval of the orbit, a timer is started, provided in the control unit of the spacecraft, with a duration equal to the maximum duration of the "shadow" interval of the orbit; after leaving the "shadow" interval of the orbit with a faulty on-board computer, according to the timer signal, the spacecraft is switched to operation mode using an autonomous control loop, and with a working on-board computer, the timer is turned off according to information from the onboard ballistic software, and the spacecraft is controlled according to information a serviceable on-board computer.

The essence of the invention lies in the fact that a terminator pulse signal is generated and when the spacecraft enters the "shadow" interval of the orbit, the timer is started from the terminator pulse signal or according to information from the onboard ballistic software of the onboard computer with a duration equal to the maximum duration of the shadow area; for solar cells, the panels of which are rigidly fixed to the spacecraft body, use the rotation of the spacecraft body in the "passive" spinning mode to orient the solar batteries to the Sun; with a negative energy balance of the power supply system associated with an unplanned loss of orientation of the solar batteries of the spacecraft to the Sun, an economical mode of operation of the storage batteries of the power supply system is used.

Graphic illustrations

The given graphical figure 1 shows an example of the implementation of the proposed method of orientation of a spacecraft through a device containing the following positions:

- On-board computer (electronic computing device) - 1;

- BIB (strapdown inertial unit) - 2;

- DP (spacecraft position sensors relative to the Sun, Earth, stars) - 3;

- SE (power supply system) - 4;

- SB (solar panels) - 5;

- AB (storage battery) - 6;

- ARC (regulation and control equipment) - 7;

- Additional autonomous control loop - 8;

- Timer - 9;

- Orientation control system SB (solar batteries) - 10;

- IO (executive bodies) -11;

- KA body - 12;

- Terminator signal generator - 13;

- Element OR - 14;

- RAM (random access memory) - 15;

- ROM (read only memory) - 16;

- MP (microprocessor) -17

- BU KA (spacecraft control unit) - 18.

Control commands (CU) are transmitted from the ground control complex to the on-board computer 1, to the BU KA 18 and to the additional autonomous control loop 8, and telemetric information (TM) is transmitted from the on-board computer 1 to the ground control complex via the telemetry channel.

Description of the proposed method

When the spacecraft is separated from the rocket or the upper stage, the process of damping is carried out, then with the help of BIB 2, DP 3 and IO 11 of the control unit BU KA 18 (see patent, RF, No. 2669481) the process of alignment (alignment of the axes of the spacecraft coordinate system with the orbital coordinate systems) and subsequent stabilization of the spacecraft. At the end of the process of damping and stabilizing the spacecraft, in the automatic mode, the attitude control system SB 10 (for solar panels whose panels are not rigidly fixed to the spacecraft body, see, for example, the Kondor-E spacecraft, the main contractor of JSC VPK NPO Mashinostroyenia , Reutov), under the action of the drive motors located in it, the solar batteries SB 5 are set in position relative to the spacecraft body 12 to obtain the maximum possible value of the current generated by the SB 5 at the current point of the spacecraft's orbit (approaching the fulfillment of the condition cosα = l = const, where α is the angle between the perpendicular to the surface of SB 5 and the direction to the Sun). Solar batteries SB 5, in which their panels are rigidly fixed to the hull in a number of modern spacecraft (see, for example, the Kanopus-V spacecraft, the lead executor AO "Corporation" VNIIEM ", Moscow), is oriented to the Sun by turning the spacecraft body 12 by the control unit of the spacecraft BU KA 18 (BIB 2, DP 3 and IO 11), including twisting the spacecraft 12 body around the direction on the Sun (the "passive" spin mode with the orientation of SB 5 on the Sun, i.e. solar orientation mode). In this case, each time during the target work (for example, conducting a survey), the spacecraft body 12 is rotated from the solar orientation mode to the orbital orientation (for example, the longitudinal axis of the spacecraft, which coincides with the longitudinal axis of the optoelectronic module, is directed to the nadir during the sub-satellite survey. points) and maintaining this orientation (active orientation mode), and then, upon completion of the target work, the spacecraft body 12 is turned back into the “passive” spin mode with the SB 5 orientation toward the Sun (see patent, No. 2621933).

Radical protection against an emergency on a spacecraft associated with a loss of orientation to the Sun when the spacecraft moves at flight "light" intervals of the orbit can be an automatic transition from the main to a backup mode of spacecraft attitude control relative to the direction to the Sun, while the use of on-board computer 1 is temporarily stopped ... Such a mode of operation cannot provide the full functionality of the spacecraft, but it guarantees a positive energy balance, which ensures the survivability of the spacecraft. The transition to the standby attitude control mode is carried out according to the "hard" logic, i.e. without using the on-board computer 1, when the spacecraft is affected by various factors of outer space, for example, local static discharges, leading to the failure of the on-board computer 1. In the standby mode of the spacecraft attitude control, an additional autonomous control loop 8 is put into operation, which installs SB 10 through the attitude control system (for solar batteries, the panels of which are not rigidly fixed to the KA 12 body) or through BIB 2, DP 3 and IO 11 of the BU KA 18 spacecraft control unit (for solar batteries whose panels are rigidly fixed to the KA 12 body, the "passive" mode twists with the orientation of SB 5 to the Sun) solar batteries SB 5 to obtain their maximum illumination, and the subsequent resumption of the spacecraft orientation using the on-board computer 1 is carried out by radio command (CU) from the ground control center (see patent, RF, No. 2669481).

When the spacecraft moves in the flight "shadow" intervals of the orbit, its power supply is carried out exclusively from the storage batteries of the AB, in this mode a negative energy balance occurs. The shadow parameters (start and end times) for each orbit are calculated by the onboard ballistic software of the onboard computer 1. If during normal operation of the spacecraft during the passage of the "shadow" interval of the orbit, the onboard computer malfunctions, then all software will completely cease to function, and there will be information about the end of the shadow area. Consequently, the spacecraft will start to lose orientation. And since the on-board computer is faulty, the sign of the end of the shadow area will not be generated upon exiting the shadow section of the spacecraft. As a result, the spacecraft will not be able to restore the orientation of the solar panels to the Sun, which, in turn, will lead to a deep discharge of AB 6 and a possible failure of the spacecraft. Therefore, in the spacecraft control unit BU KA 18, as in the prototype, a timer 9 is provided, with a duration equal to the maximum duration of the spacecraft passage through the "shadow" orbit interval (the duration of the spacecraft passage through the orbit changes with a change in its inclination, as well as seasonal operating conditions), which is launched according to information from the onboard ballistic software when controlling the spacecraft using a serviceable onboard computer when entering the "shadow" interval of the orbit. However, in the event of a malfunction of the on-board computer near the terminator ("light-shadow" boundary), when entering the "shadow" interval of the orbit, timer 9 will not be started, and upon the exit of the spacecraft from the "shadow" interval of the orbit, the sign of the end of the "shadow" interval. It should be noted that the terminator area is characterized by adverse effects on the spacecraft, since On the surface of the spacecraft, a significant gradient of potential can arise due to the non-equalization of the potentials of the illuminated and unlit surfaces of the spacecraft. The so-called differential charging of the surface occurs, which can also arise due to the difference in the secondary emission characteristics of materials on the surface, the difference in the conditions for the ingress of plasma on individual parts of the surface and the presence of structural inhomogeneities (see R.Yu.Dorofeev. "Improving the energy efficiency of the space power supply system spacecraft by using the energy of the electrostatic charge of the surface of the spacecraft in orbital operating conditions. "Russian Space Systems, 53 Aviamotornaya St., Moscow, 111250, Russia e-mail: myhavkedah@mail.ru. Electronic journal" Proceedings of MAI. " Issue No. 68.).

To eliminate this significant drawback of the prototype in the proposed method, pulses are generated by the signal shaper of the terminator 13 in a continuous mode with a repetition period equal to the duration of the orbit, which, in the event of a malfunction of the on-board computer in the terminator region, enable timer 9 to start.

As a terminator signal generator 13, you can use, for example, random access memory RAM 15 of a static type with a capacity of 256 bytes based on a LSI type M1821RU55, a read-only memory device ROM 16 built on a single microcircuit of the M1623RT1A type with single electrical programming and an MP 17 microprocessor of the M1821VM85A type, which implements all functions for organizing work, synchronizing and performing the necessary computing operations. When the MP 17 accesses the RAM 15, information is written into the memory cells of the RAM 15 or the transfer of information from the memory cells of the RAM 15, in the absence of access, the RAM cells 15 are in the information storage mode. The ROM 16 is flashed with software, which includes a set of operating and control programs, as well as tables of time constants (time settings). In accordance with the software embedded in the ROM 16, the MP 17 microprocessor organizes the work in several hard cycles, while the ROM 16 is accessed only by the MP 17 signal and the contents of the selected ROM 16 memory cell are output to the bus.

When the spacecraft passes orbit in the terminator region, according to information from the on-board ballistic software using the on-board computer 1 (according to the KU from the ground control complex with a faulty on-board computer 1), entering the terminator signal generator 13, at its output (RAM port 15), a sequence of continuous impulse signals with a repetition period corresponding to the duration of a given orbit (formed according to a time setting in ROM 16). Timer 14 is started with a signal from the output of the OR element 14, generated according to information from the on-board ballistic software when controlling the spacecraft using a serviceable on-board computer 1 or from the terminator signal generator 13 supplied to the inputs of the OR element 14. Therefore, during the entire service life of the spacecraft, timer 9 will start reliably, including with a faulty on-board computer 1 (no on-board ballistic software) in the terminator area. As an element OR 14, you can use the 564LE5 microcircuit. Depending on the orbital inclination and the seasonal operating conditions of the spacecraft, the repetition period of the terminator impulse signals is corrected according to information from the onboard ballistic software using the onboard computer 1 supplied to the terminator signal generator 13.

To improve the reliability and survivability of the power supply system of the SC 4 spacecraft due to emerging situations associated with an unplanned loss of orientation of the SB 5 to the Sun, the ARC 7 regulation and control equipment uses an economical mode of operation of storage batteries (see patent, RF, No. 2706762).

Thus, the claimed invention

позволяет надежно обеспечить эффективную ориентацию панелей солнечных батарей относительно направления на Солнце в течение всего срока активного существования космического аппарата;

allows you to reliably ensure the effective orientation of solar panels relative to the direction to the Sun during the entire active life of the spacecraft;

при отрицательном энергобалансе системы электропитания обусловленным незапланированной потерей ориентации солнечных батарей космического аппарата на Солнце, позволяет использовать экономичный режим работы аккумуляторных батарей системы электропитания и тем самым обеспечить высокую надежность и живучесть космического аппарата.

with a negative energy balance of the power supply system caused by an unplanned loss of orientation of the solar batteries of the spacecraft to the Sun, it allows the use of an economical mode of operation of the power supply system batteries and thereby ensure high reliability and survivability of the spacecraft.

In addition, the installation of solar panels with panels fixed both not rigidly and rigidly on the body of the spacecraft, expands the functionality in case of violation of the orientation of the spacecraft relative to the direction to the Sun while maintaining high reliability and survivability of the spacecraft.

Claims (1)

A method of orientation of a spacecraft, including orientation of a spacecraft relative to the direction to the Sun and the Earth using an on-board computer according to information from sensors for determining the angular position, orientation of the spacecraft relative to the direction to the Sun using an additional autonomous control loop connected to control in case of violation of orientation of the spacecraft relative to the direction on the Sun, and with the installation of solar panels, not rigidly fixed on the body of the spacecraft, in a fixed position relative to the body of the spacecraft, and when controlling the spacecraft using a serviceable on-board computer when entering the shadow interval of the orbit, a timer is started, provided in the control unit of the spacecraft spacecraft, with a duration equal to the maximum duration of the shadow interval of the orbit, and after leaving the shadow interval of the orbit in the event of a malfunction the on-board computer, according to the timer signal, the spacecraft is switched to the operation mode using an autonomous control loop, and if the on-board computer is in good working order, the timer is turned off according to the information from the on-board ballistic software, and the spacecraft is controlled according to the information of the working on-board computer, characterized in that a pulse the terminator signal and when the spacecraft enters the shadow interval of the orbit, the timer is started from a pulse signal of the terminator or according to information from the onboard ballistic software of the onboard computer, while solar batteries, the panels of which are fixed on the spacecraft body, use the rotation of the spacecraft body in passive mode twists for the orientation of solar batteries to the Sun, while with a negative energy balance of the power supply system due to an unplanned loss of orientation of the solar batteries of the spacecraft on The sun uses an economical mode of operation of the battery power supply system.

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