CN101477376A - Fault injection device and method for spacecraft actuating mechanism - Google Patents

Abstract

The invention discloses a spacecraft actuator fault injection device and a fault injection method thereof, which belong to the field of actuator fault analysis and reliability verification. The device of the present invention comprises: a main board, a multi-channel data acquisition card, a multi-channel analog output card, a man-machine interface, a DC voltage stabilizer and a signal adapter board. The method of the present invention extracts and processes the actuator control command signal and the rotational speed feedback signal to obtain the false command signal and the false rotational speed feedback signal. The invention adopts the fault injection method realized by software combined with hardware to inject faults into the actuators of the spacecraft. The invention realizes the fault injection of the executive mechanism, accelerates the generation of system faults, and improves the efficiency of system fault diagnosis; the fault injection device has low cost, strong operability, convenient and reliable use.

Description

Fault injection device and fault injection method for spacecraft actuator

technical field

The invention relates to a spacecraft actuator fault injection device and a fault injection method thereof, belonging to the field of actuator fault analysis and reliability verification in the semi-physical simulation test stage of a spacecraft attitude control system.

Background technique

Fault injection technology is an important means of evaluating the performance of fault-tolerant systems. It speeds up the test process of evaluating fault-tolerant mechanisms by introducing faults into the system consciously. The development cost of spacecraft is high and the cycle is long. In order to ensure the long-life and high-reliability operation of the spacecraft, it is necessary to fully carry out reliability inspections on every link of the spacecraft. The emergency treatment, fault detection and diagnosis link in the event of a failure of the spaceborne actuator is a link that needs to be fully tested on the ground. The fault injection device and method described in the present invention adopts a certain strategy to artificially introduce faults into the actuators of the spacecraft, thereby accelerating the failure of the actuators and providing prerequisites for the reliability verification of the attitude control system scheme.

According to the implementation method of fault injection, it can be divided into simulated fault injection and physical fault injection. The physical fault injection method can be divided into hardware implementation and software implementation of fault injection.

Different fault injection methods have different effects on the same target system, so the efficiency of fault injection is also different. Choosing an appropriate injection method not only saves investment and brings good injection results, but also for a specific system, it is likely that only a certain method can achieve effective fault injection, such as a black box-based system, where the code is invisible and only Provides limited access rights, and at this time only the method of interacting with the interface can be used. Therefore, for the fault injection of the target system, it is very important to select a fault injection method suitable for the system.

Simulated fault injection does not require special hardware support and is inexpensive. But for the target system spacecraft actuator in this paper, it is difficult to establish a system model by means of simulation. The composition of the actuator is complex, and there are many components and parts. If a certain accuracy requirement is met, the hardware description language is used to realize the system simulation model, and the development workload will be huge.

One of the most important problems of the hardware fault injection method is that it directly injects faults into the hardware of the target system, that is, a complete hardware system to be injected is required. In this paper, if the fault injection method implemented by hardware is adopted, the hardware model of the satellite attitude control system part must be established for fault injection experiments. However, the hardware model of the satellite attitude control system requires high technical requirements, a large amount of engineering, and a high cost. Moreover, as the system packaging density becomes higher and higher, it becomes more and more difficult to access the injection node during hardware fault injection, and it may cause damage to the target system. Therefore, hardware fault injection is not suitable for fault injection of expensive development costs such as spacecraft components.

The fault injection method implemented by software is based on a certain fault model, through software methods, by modifying the state variables or data of hardware or software to simulate the occurrence of faults. It does not require additional hardware devices, and the fault injection location can be selected on the hardware or software that can be accessed by program instructions, and the fault injector is simple to implement. However, simple software fault injection cannot simulate the status of real components, and it is difficult to approach the actual system.

Contents of the invention

The technical problem to be solved by the present invention is to propose a device and a fault injection method for spacecraft actuator fault injection aiming at the defects existing in the prior art.

The spacecraft actuator fault injection device of the present invention is characterized in that it includes: a main board, a multi-channel data acquisition card, a multi-channel analog output card, a man-machine interface, a DC voltage stabilizer and a signal adapter board; wherein the output of the signal adapter board The terminal is connected to the input terminal of the multi-channel data acquisition card, the output terminal of the multi-channel data acquisition card is connected to the input terminal of the mainboard, the output terminal of the mainboard is connected to the input terminal of the multi-channel analog output card, and the output terminal of the multi-channel analog output card is connected to the signal converter Connect the input end of the board, the human-machine interface is electrically connected with the main board, and the output end of the DC stabilized power supply is respectively connected to the power interface of the main board, the power interface of the multi-channel data acquisition card, and the power interface of the multi-channel analog output card.

The method for fault injection of the spacecraft actuator fault injection device is characterized in that it comprises the following steps:

a.) Use the man-machine interface to set the fault type, that is, stuck fault, slowly changing fault or constant value bias fault;

b.) The multi-channel data acquisition card is used to receive the command signal output by the on-board computer through the signal adapter board;

c.) The fault type set in step a and the instruction signal described in step b pass through the main board, the multi-channel analog output card, and the signal adapter board to output the pseudo-instruction signal in sequence;

d.) Using the actuator to receive the pseudo-instruction signal described in step c to output the rotational speed signal;

e.) Pass the speed signal described in step d through the signal adapter board, multi-channel data acquisition card, main board, multi-channel analog output card in sequence, and then output the false speed signal to the onboard computer through the signal adapter board.

The invention adopts the fault injection method realized by software combined with hardware to inject faults into the actuators of the spacecraft. The method used in the present invention realizes the fault injection of the actuator without damaging the physical parts of the actuator, accelerates the generation of system faults, and improves the efficiency of system fault diagnosis; for the reliability analysis of the attitude control system scheme and the fault handling of the actuator Validation has played an important role. The fault injection device has the advantages of low cost, strong operability, convenient use and reliability.

Description of drawings

Figure 1: Schematic block diagram of spacecraft actuator fault injection;

Fig. 2: hardware structural diagram of the present invention;

Figure 3: Structural diagram of an embodiment of the present invention;

Figure 4: Flow chart of spacecraft actuator fault injection software.

Detailed ways

As shown in Figure 1. The hardware for fault injection of spacecraft actuators includes onboard computer, fault injection device, man-machine interface and actuators.

as shown in picture 2. The spacecraft actuator fault injection device of the present invention includes: a main board, a multi-channel data acquisition card, a multi-channel analog output card, a man-machine interface, a DC voltage stabilizer and a signal adapter board; wherein the output terminal of the signal adapter board is connected to a multi-channel The input end of the data acquisition card, the output end of the multi-channel data acquisition card are connected to the input end of the main board, the output end of the main board is connected to the input end of the multi-channel analog output card, and the output end of the multi-channel analog output card is connected to the input of the signal adapter board The man-machine interface is electrically connected to the main board, and the output end of the DC stabilized power supply is respectively connected to the power interface of the main board, the power interface of the multi-channel data acquisition card, and the power interface of the multi-channel analog output card.

The method for the fault injection of the spacecraft actuator fault injection device includes the following steps:

a.) Use the man-machine interface to set the fault type, that is, stuck fault, slowly changing fault or constant value bias fault;

b.) The multi-channel data acquisition card is used to receive the command signal output by the on-board computer through the signal adapter board;

c.) The fault type set in step a and the instruction signal described in step b pass through the main board, the multi-channel analog output card, and the signal adapter board to output the pseudo-instruction signal in sequence;

d.) Using the actuator to receive the pseudo-instruction signal described in step c to output the rotational speed signal;

e.) Pass the speed signal described in step d through the signal adapter board, multi-channel data acquisition card, main board, multi-channel analog output card in sequence, and then output the false speed signal to the onboard computer through the signal adapter board.

The set fault types include: (1) stuck fault: collect the feedback signal of the actuator, process the instantaneous feedback signal into a pseudo speed signal, that is, take 0 and output it, and simulate the stuck fault of the actuator; (2) slow-change fault : This fault model generates a linear time-varying fault function, which is injected into the actuator to simulate the slowly changing fault of the actuator; (3) Constant value bias fault: This fault model superimposes a constant value signal on the feedback signal of the actuator, Synthesize the pseudo-feedback signal of the actuator and output it.

As shown in Figure 3, the fault injection device and injection method are described with the flywheel as the actuator, and the flywheel and the fault injection device are connected to a small satellite attitude control semi-physical simulation closed-loop loop, which includes the following parts: satellite motion simulation The computer is used to calculate the satellite attitude and orbital motion equation; the space-borne sensor is used to be sensitive to the current satellite attitude information, the space-borne computer collects the attitude information, calculates the control law, and gives the flywheel instruction information, and the fault injection device is based on the current system state and selection The failure mode injects faults into the flywheel. The main hardware interfaces are:

1. Connect the flywheel speed command channel, flywheel speed feedback signal, and flywheel pseudo-feedback signal processed by the fault injection device to the AD650 multi-channel data acquisition card of the fault injection device through the adapter board;

2. Connect the flywheel pseudo-command signal processed by the fault injection device to the XMM1612 multi-channel analog output card; the DC stabilized voltage source supplies power to the PC104 combination module, that is, the main board. Turn on the fault injection procedure.

The specific working steps of the fault injection device are as follows:

(1) Set the speed change rate range of the flywheel under normal working condition;

(2) From the man-machine interface, inject the flywheel fault information as stuck fault;

(3) The AD650 multi-channel data acquisition card collects the flywheel instruction signal given by the on-board computer;

According to the fault injection information (ie: stuck fault), the fault injection device treats the pseudo command signal of the momentum wheel as 0, and outputs it to the momentum wheel;

(4) Collect flywheel feedback signal. If the momentum wheel speed telemetry is non-zero, the fault injection device processes the flywheel speed feedback signal to 0, and this signal is called a false speed feedback signal, which is sent to the on-board computer.

(5) The fault injection device judges the flywheel speed change rate and the set normal speed change rate range to analyze the relationship between the flywheel pseudo feedback signal and the injection fault. If it exceeds the normal speed change rate range set by the flywheel, it is determined that the flywheel has occurred If the fault phenomenon is stuck, it means that the fault injection is successful.

As shown in Figure 4, it is the flow chart of the fault injection software of the actuator.

Claims (2)

1. a spacecraft topworks fault injection device is characterized in that comprising: mainboard, multi-channel data acquisition card, multichannel analog output card, man-machine interface, direct-flow voltage regulation source and Signals Transfer Board; The input end of the output termination multi-channel data acquisition card of Signals Transfer Board wherein, the input end of the output termination mainboard of multi-channel data acquisition card, the input end of the output termination multichannel analog output card of mainboard, the input end of the output termination Signals Transfer Board of multichannel analog output card, man-machine interface is electrically connected with mainboard, and the output terminal of D.C. regulated power supply connects the power interface of mainboard, the power interface of multi-channel data acquisition card, the power interface of multichannel analog output card respectively.

2. a method of injecting based on the fault of the described spacecraft of claim 1 topworks fault injection device is characterized in that comprising the steps:

A.) adopting man-machine interface that fault type is set is stuck fault, gradual fault or normal value biasing fault;

B.) adopt the multi-channel data acquisition cartoon to cross the command signal that Signals Transfer Board receives spaceborne computer output;

C.) fault type that step a is provided with and the described command signal of step b are successively through mainboard, multichannel analog output card, Signals Transfer Board output pseudoinstruction signal;

D.) adopt the described pseudoinstruction signal of the receiving step c of topworks output speed signal;

E.) the described tach signal of steps d is exported pseudo-tach signal to spaceborne computer by Signals Transfer Board behind process Signals Transfer Board, multi-channel data acquisition card, mainboard, the multichannel analog output card successively again.

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