RU2481250C1 - Spacecraft angular motion stabilisation system - Google Patents

Abstract

FIELD: transport.

SUBSTANCE: invention relates to aerospace engineering and may be used in spacecraft onboard control systems. Proposed system comprises three control channels. Every said control channel comprises control signal setting device, angular velocity transducer, unit of intermittent switching, switch, unit of jet engines, angle transducer, comparator, adding amplifier and relay element connected in series. Comparator is connected with control signal setting device, adding amplifier is connected with angular velocity transducer, and intermittent switching unit is connected with switch.

EFFECT: lower power consumption, decreased weight, minimised quantity of jet engines.

4 dwg

Description

The invention relates to airborne spacecraft (SC) control systems.

A known stabilization system comprising in each control channel a control signal setter, an angle sensor, an angular velocity sensor, a comparison element, a summing amplifier and a relay element [1].

Closest to the proposed invention is a system for stabilizing the angular motion of a spacecraft, containing three control channels, each control channel contains a control signal adjuster, an angular velocity sensor, an angle sensor connected in series, a comparison element, the second input of which is connected to a control signal adjuster, a summing amplifier, and a second the input of which is connected to the angular velocity sensor, and the relay element [2].

In these stabilization systems, jet engines are traditionally used as executive bodies, providing control over the three axes of the spacecraft.

A disadvantage of the known solutions is that traditionally for the implementation of the 3 channels of stabilization of the spacecraft requires 6 pairs of jet engines. Also, with independent control, at certain points in time, in the general case, 6 engines can be switched on simultaneously, which may be unacceptable from the point of view of meeting the requirements for energy consumption.

The technical problem solved in the proposed stabilization system is to reduce energy consumption and reduce the weight of the system.

The specified technical problem is achieved by the fact that in the known system for stabilizing the angular motion of a spacecraft containing three control channels, each of which contains a control signal adjuster, an angular velocity sensor, an angle sensor connected in series, a comparison element, the second input of which is connected to the output of the control signal , the summing amplifier, the second input of which is connected to the output of the angular velocity sensor, and the relay element, are additionally introduced series-connected block odic switching switch, three signal inputs which are connected respectively with the output of the relay elements for each control channel block and jet engines, whose output is the output of the stabilization system.

In Fig. 1, a block diagram of a system for stabilizing the angular motion of a spacecraft is shown; Fig. 2 is a static characteristic of a relay element with a dead zone of a spacecraft control channel along the X axis (similar characteristics have relay elements in the control channels relative to the U and Z axes), Fig. .3 one embodiment of a jet engine layout is presented.

The stabilization system of the angular motion of the spacecraft (figure 1) contains three control channels 1, 2 and 3 relative to the 3 axes of the spacecraft, respectively. Each control channel, for example, control channel 1, has a control signal setter 4 (ZSU), an angular velocity sensor 5 (ДУС), an angle sensor 6 (ДУ) connected in series, a comparison element 7 (ЭС), the second input of which is connected to the output of the signal setter control 4, the summing amplifier 8 (SU), the second input of which is connected to the output of the angular velocity sensor 5, and the relay element 9 (RE), connected in series to the periodic switching unit 10 (BOD), switch 11 (PC), the three signal inputs of which are connected respectively, with output p an oil element 9 of each control channel, and a jet engine block 12 (BRD), the output of which is the output of the system.

The stabilization system of the angular motion of the spacecraft operates as follows.

The control channels 1, 2 and 3, the control signal setting unit 4, respectively, are set _back control signals γ (t), Ψ _backside (t), θ _backside (t). In each channel, by the corresponding control signals γ _ass (t), Ψ _ass (t), ϑ _ass (t), the current signals of the angular position γ (t), Ψ (t), ϑ (t) and the angular velocity ω _x (t ), ω _y (t), ω _z (t) KA the law of regulation (stabilization) is formed. For example, in control channel 1, this law is formed by blocks 4–9.

In the summing amplifier 8, a control signal σ _x (t) is formed in the form:

where Δγ (t) is the mismatch signal generated by the comparison element 7 by the signals γ _ass (t) from the control signal setter 4 and γ (t) from the angle sensor 6:

K _γ , K _ωх - gear ratios of the summing amplifier 8;

ω _x (t) is the angular velocity signal of the spacecraft coming from the angular velocity sensor 5.

Next, the control signal σ _x (t) is fed to the input of the relay element 9, the characteristic of which is shown in Fig.2. The value of the dead zone σ _0x relay element 9 is determined by the required stabilization accuracy. The stabilization accuracy γ ₀ corresponds to:

Received at the output of the relay element 9, the signal F _x (σ _x ) is fed to the 1st input of the switch 11.

Similarly, in the control channels 2 and 3 of the stabilization system, signals F _y (σ _y ) and F _z (σ _z ), respectively, are supplied to the 2 and 3 inputs of switch 11.

The periodic switching unit 10 sets the switching period T of the control signals F _x (σ _x ), F _y (σ _y ) and F _z (σ _z ) at the input of the jet engine block 12 to provide the required angle accuracy.

Figure 3 presents one of the layout of the jet engines RD1, RD2, RD3 and RD4, which allows to implement the proposed system for stabilizing the angular motion of the spacecraft. In this embodiment, jet engines are located relative to each other at a distance of L1 = 2.9 m (along the Y axis), L2 = 1.25 m (along the Z axis) and L3 = 0.75 m (along the X axis).

By the control signals F _x (σ _x ), F _y (σ _y ), F _z (σ _z ) in the block of jet engines 12, the corresponding 2 stabilization engines are turned on, creating a control moment M _control .

The inclusion of engines for the location of jet engines, presented in figure 3, is carried out in accordance with table 1.

Table 1 No. F _x (σ _x ) = 1 F _y (σ _y ) = 0 F _z (σ _z ) = 0 F _x (σ _x ) = - 1 F _y (σ _y ) = 0 F _z (σ _z ) = 0 Fy (σ _y ) = 1 F _x (σ _x ) = 0 F _z (σ _z ) = 0 F _y (σ _y ) = - 1 F _x (σ _x ) = 0 F _z (σ _z ) = 0 F _z (σ _z ) = 1 F _x (σ _x ) = 0 F _y (σ _y ) = 0 Fz (σ _z ) = - 1 Fx (σ _x ) = 0 Fy (σ _y ) = 0 one RD3, RD4 2 RD1, RD2 3 RD1, RD4 four RD2, RD3 5 RD2, RD4 6 RD1, RD3

Thus, the proposed system for stabilizing the angular motion of the spacecraft allows reducing the energy consumption and weight of the system by reducing the number of jet engines used (4 engines are used instead of 12 engines).

Information sources

1. B.V. Raushenbach, E.N. Tokar. Spacecraft orientation control. Moscow, 1974, p. 144.

2. Vasiliev V.N. Spacecraft orientation systems. Moscow, 2009, p. 310.

Claims (1)

The system of stabilization of the angular motion of the spacecraft, containing three control channels, each control channel contains a control signal adjuster, an angular velocity sensor, an angle sensor connected in series, a comparison element, the second input of which is connected to the output of the control signal adjuster, a summing amplifier, the second input of which is connected to the output of the angular velocity sensor, and a relay element, characterized in that the system comprises serially connected periodic switching unit, a switch, t and signal inputs of which are connected respectively with the output of relay elements for each control channel block and jet engines, whose output is the output of the stabilization system.

Images