Flexible spacecraft sensor fault adjustment method

Abstract

The present invention discloses a flexible spacecraft sensor fault adjustment method, belonging to the field of aerospace flight control technology. A fault estimation module and a fault tolerance controller are mainly employed by the flexible spacecraft sensor fault adjustment method, and the method comprises the steps that: a filter and an adaptive observer are employed to form a fault estimation module; fault estimation information and sensor output signals are employed to establish the fault tolerance controller through combination of adaptive integral sliding mode control technology; through adoption of the Lyapunov stability theory, the asymptotic stability of a system is proved in a condition of generation of sensor faults; and finally, a simulation experiment result proves the validity of the method provided by the invention. The fault tolerance control problem when sensor measurement offset faults are generated in an operation process of a flexible spacecraft is solved so thataccurate control of an attitude angle in the sensor fault condition is achieved and the system has a high tolerance capability for the faults; and moreover, the method fully takes the consideration of disturbances generated by spacecraft parameter uncertainty and flexible accessories in the design process and is suitable for engineering application.

Description

technical field [0001] The invention belongs to the technical field of aerospace flight control, in particular to a flexible spacecraft sensor fault adjustment method based on adaptive integral sliding mode output feedback control. Background technique [0002] At present, flexible spacecraft is an important basic platform for performing major space tasks such as space exploration, space infrastructure construction, and earth observation. Therefore, research on flexible spacecraft has an important impact on space planning, military activities, scientific research, and political economy. Great attention has been paid by the aerospace powers. Flexible spacecraft usually have flexible accessories such as large and complex deployment antennas, solar panels, and robotic arms. Compared with traditional spacecraft, the structure is more complex, and the attitude dynamic parameters of flexible spacecraft are uncertain. Affected by factors such as manufacturing level, construction c...

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Problems solved by technology

[0004] (1) When using the traditional fault estimation method based on coordinate transformation technology to transform the sensor problem into the actuator problem, there are relatively strict assumptions on the output matrix of the system, which is not conducive to wide application and promotion;

[0005] (2) The accuracy of fault estimation is poor and difficult to control;

[0006] (3) When the sliding mode movement is maintained, it will cause severe chattering of the system;

[0007] (4) It takes too long for the system state to reach the sliding surface, which is not time-sensitive

[0008] For example, Chinese patent CN106094514 discloses an active fault-tolerant control method for flexible spacecraft based on dynamic output feedback control. This method first transforms the dynamic equation of the attitude control system of the flexible spacecraft into a general state space equation, and then establishes an additive sensor Measure the fault model of the offset, and then establish a fault detection and identification module composed of an unknown input observer and a filter to perform real-time detection and online estimation of unknown sensor faults, and finally use the obtained fault estimation value to estimate the information design based on dynamic output feedback A fault-tolerant controller, this method can enable the flexible spacecraft to reach the desired attitude normally when the additive sensor measurement offset failure occurs, and at the same time, the modeling uncertainty and the disturbance caused by the flexible attachment are considered in the design process. The influence caused by the system, and the fault diagnosis and identification module and the fault-tolerant controller can be designed separately; although the patent considers the offset fault of the additive sensor measurement, it does not actually calculate and verify it

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