A method for securing an aircraft wheel load signal

Abstract

The present application belongs to the field of flight control technology, and particularly relates to a kind of safety protection methods of airplane wheel load signal, the method includes: according to landing gear is put down to position signal, landing gear is put up to position signal and landing gear handle position signal determines wheel load bearing signal precondition;According to wheel load bearing signal precondition and original wheel load signal determines protection wheel load signal;According to radio altitude, wheel speed and atmospheric surface speed signal synthesis out when airplane wheel load signal failure wheel load reconstruction value signal;According to wheel load signal failure mark protection wheel load signal and wheel load reconstruction signal are selected as wheel load integrated value signal output;Before wheel load integrated value signal output, through two-state state machine with timer, the instantaneous jump of the wheel load integrated value signal is inhibited, and is output as wheel load output value output.The present application can effectively deal with the abnormal conditions such as failure, error, jump of wheel load signal, improve the reliability of airplane air / ground state judgment, and improve flight control safety.

Description

Technical Field

[0001] This application belongs to the field of flight control technology, and specifically relates to a method for the safety protection of aircraft wheel-borne signals. Background Technology

[0002] The landing gear load signal (or wheel load signal) indicates whether the aircraft is currently on the ground by measuring whether the landing gear struts are compressed and under load. It is an important parameter for pilots to judge the aircraft's air / ground status and a key core signal of modern aircraft fly-by-wire flight control systems.

[0003] In modern fly-by-wire flight control systems, aircraft typically execute different control laws and exhibit different handling response characteristics in the air and on the ground. Furthermore, the difference in air / ground status also involves the activation / deactivation of protective functions such as angle of attack, overload, and speed protection. Therefore, wheel-mounted signals used to determine the aircraft's air / ground status are crucial for the safe operation of modern aircraft fly-by-wire flight control systems.

[0004] To ensure high reliability of wheel-mounted signals, redundancy is typically configured in engineering practice. Furthermore, when all redundant wheel-mounted signals fail, they are usually reconstructed to a fixed state as a safety value. Despite this, simultaneous failures of redundant wheel-mounted signals still occur in actual aircraft operation, impacting flight safety. Moreover, the method of reconstructing to a fixed safety value cannot accurately reflect the aircraft's true air / ground status, leading to a significant degradation in aircraft control performance.

[0005] To enhance the fault tolerance of modern fly-by-wire flight control systems and make the air / ground status judgment of the flight control system more reliable and safer, it is necessary to use heterogeneous signals to protect and reconstruct the aircraft wheel-borne signals. Summary of the Invention

[0006] To address the aforementioned problems, this application provides a method for ensuring the safety of aircraft wheel-mounted signals, characterized by comprising:

[0007] The prerequisites for wheel load bearing signals are determined based on the landing gear lowering-in signal, the landing gear retraction-in signal, and the landing gear handle position signal.

[0008] The protective wheel load signal is determined based on the preconditions of the wheel load signal and the original wheel load signal; the wheel load reconstruction value signal when the aircraft wheel load signal fails is synthesized based on the radio altitude, wheel speed and air speed signal.

[0009] Based on the wheel-mounted signal fault indicator, the wheel-mounted protection signal and the wheel-mounted reconfiguration signal are selected and output as the wheel-mounted comprehensive value signal.

[0010] Before the wheel load composite value signal is output, the instantaneous jump of the wheel load composite value signal is suppressed by a two-state state machine with a timer, and then output as the wheel load output value.

[0011] The wheel load bearing signal prerequisite is valid when any one of the following three conditions is true: the landing gear lowered to position signal is true, the landing gear retracted to position signal is false, or the landing gear handle lowered signal is true.

[0012] The protection wheel load signal is valid when both the preconditions for the wheel load signal and the original wheel load signal are valid.

[0013] The specific methods for determining the wheel load reconfiguration value signal include:

[0014] The wheel load reconstruction value signal is valid when the radio altitude is less than the threshold, the wheel speed is greater than the threshold, and the speedometer speed is less than the threshold simultaneously.

[0015] The selection of the wheel load composite value signal includes: when the wheel load signal fault mark is valid, the wheel load reconstructed value signal is used as the wheel load composite value signal; when the wheel load signal fault mark is invalid, the protection wheel load signal is used as the wheel load composite value signal.

[0016] The specific method for suppressing the instantaneous jump of the wheel load composite value signal includes: if the wheel load composite value signal is continuously invalid for n1 consecutive seconds, the wheel load output value is invalid; if the wheel load composite value is continuously valid for n2 consecutive seconds, the wheel load output value is valid; if neither of the above two conditions is met, the wheel load output value remains unchanged from its previous state.

[0017] When the landing gear is in the lowered position signal is true or the landing gear is in the retracted position signal is false, the landing gear lowered status signal is valid; when the landing gear lowered status signal is valid or the landing gear handle position signal is lowered, the wheel load bearing signal prerequisite is valid.

[0018] The advantages of this application include: This invention provides a safety protection method for aircraft wheel-borne signals. Using landing gear position signals and landing gear handle signals as preconditions, it logically protects the wheel-borne signals, effectively preventing dangerous wheel-borne signal malfunctions during flight. Using radio altitude, wheel speed, and airspeed signals to logically reconstruct the aircraft's grounding state serves as a backup in case of wheel-borne signal failure, effectively improving the accuracy of the flight control system's air / ground status judgment under wheel-borne failure conditions and ensuring the control performance of the flight control system. Using a two-state machine with a timer effectively suppresses interference from instantaneous signal jumps on the wheel-borne output results, improving the stability of the wheel-borne judgment results. Furthermore, the landing gear handle, landing gear lowered, and landing gear retracted signals used in the preconditions, as well as the radio altitude, wheel speed, and airspeed signals used in the reconstruction logic, are all from different sources than the wheel-borne signals, effectively avoiding common-mode faults with the wheel-borne signals. Finally, all of the above signals are conventional and common signals on modern aircraft. The protection logic provided by this invention can be implemented through software and algorithms without adding additional hardware, demonstrating good economic efficiency. In summary, this invention provides better safety protection against failure modes and abnormal conditions such as failure, error, and jump in aircraft wheel-borne signals, and improves the safety and stability of wheel-borne signals and aircraft air / ground status judgment, thus having high application value in the aviation and aerospace industries. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of a safety protection method for aircraft wheel-mounted signals according to this application. Detailed Implementation

[0020] To make the technical solution and advantages of this application clearer, the technical solution of this application will be described in a clearer and more complete manner below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only some embodiments of this application, and are only used to explain this application, not to limit this application. It should be noted that, for ease of description, only the parts related to this application are shown in the accompanying drawings. Other related parts can be referred to the general design. In the absence of conflict, the embodiments and technical features in the embodiments of this application can be combined with each other to obtain new embodiments.

[0021] Furthermore, unless otherwise defined, the technical or scientific terms used in this application description shall have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms "upper," "lower," "left," "right," "center," "vertical," "horizontal," "inner," and "outer," etc., used in this application description to indicate relative direction or positional relationship are used only to indicate relative orientation or positional relationship, and do not imply that the device or component must have a specific orientation, or be constructed and operated in a specific orientation. When the absolute position of the described object changes, its relative positional relationship may also change accordingly, and therefore should not be construed as a limitation on this application. The terms "first," "second," "third," and similar terms used in this application description are used only for descriptive purposes to distinguish different components, and should not be construed as indicating or implying relative importance. The terms "a," "one," or "the," etc., used in this application description should not be construed as an absolute limitation on quantity, but should be construed as indicating the existence of at least one. The terms "including," "comprising," etc., used in this application description mean that the element or object preceding the word covers the element or object listed after the word and its equivalents, without excluding other elements or objects.

[0022] Furthermore, it should be noted that, unless otherwise explicitly specified and limited, terms such as “installation,” “connection,” and “linkage” used in the description of this application should be interpreted broadly. For example, a connection can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; or it can be a connection within two components. Those skilled in the art can understand its specific meaning in this application according to the specific circumstances.

[0023] like Figure 1 As shown, the method includes: precondition logic for wheel-borne signal carrying, equivalent reconstruction logic for wheel-borne signal faults, comprehensive judgment logic for preconditions / equivalent reconstruction and original wheel-borne signals, and delay stabilization logic for wheel-borne output results. Specifically: 1) Precondition logic uses the aircraft landing gear down-to-position signal, landing gear retracted-to-position signal, and landing gear handle position signal to synthesize the landing gear down status indicator, serving as the precondition for the aircraft wheel-borne signal carrying; 2) Equivalent reconstruction logic uses radio altitude, wheel speed, and air speed signals to synthesize the aircraft touchdown taxiing status indicator, serving as a reconstruction alternative for aircraft wheel-borne signal faults; 3) Comprehensive judgment logic uses multi-level AND and OR gate logic to synthesize the original wheel-borne signal, preconditions, and equivalent reconstruction, improving the wheel-borne judgment logic's tolerance to input signal faults; 4) Delay stabilization logic uses a two-state machine with a timer to suppress the interference of instantaneous signal jumps on the wheel-borne judgment result, improving the stability of the judgment result. Specifically, it includes:

[0024] (1) Precondition logic.

[0025] The landing gear deployment status is determined by combining the landing gear lowering position signal, landing gear retraction position signal, and landing gear handle position signal, serving as a prerequisite for the aircraft wheel load bearing signal. The system uses both the landing gear deployment status and landing gear handle position signals for logical judgment, with an "OR" logic between the two input signals and the output signal to accommodate situations where either the landing gear deployment status or landing gear handle position signal fails.

[0026] The determination of the landing gear status uses two signals simultaneously: landing gear in the lowered position and landing gear not in the retracted position. The two input signals are connected by an "OR" logic to accommodate the situation where either the landing gear in the lowered position or the landing gear in the retracted position signal fails.

[0027] The above two layers of judgment logic can also be equivalent to one layer, that is, the three input conditions "landing gear down in position is true", "landing gear retracted in position is not true" and "landing gear handle down is true" are combined using "OR" logic. If any one of the input conditions is satisfied, it is considered that "the precondition of wheel load bearing is true".

[0028] (2) Equivalent Reconstruction Logic.

[0029] The status indicator of whether the aircraft is taxiing or touching down is determined by combining radio altitude, wheel speed, and airspeed signals, and serves as the reconstructed value in case of a wheel-mounted signal failure.

[0030] The specific logic is as follows: when the three conditions of "radio altitude is less than the threshold value", "wheel speed is greater than the threshold value", and "indicator speed is less than the threshold value" are met simultaneously, the aircraft is considered to be in a ground taxiing state and can be used as an equivalent reconstructed signal for "wheel-borne signal carrying".

[0031] (3) Comprehensive judgment logic.

[0032] It includes two aspects: the logic for using preconditions and the logic for using reconstructed signals.

[0033] The precondition and the original wheel load signal form an AND gate logic, thereby achieving the following: the output protective wheel load is consistent with the original wheel load signal only when the precondition is true; when the precondition is not true, the output protective wheel load is non-load (0) regardless of whether the original wheel load signal is loaded (1) or not loaded (0).

[0034] The wheel-mounted signal and wheel-mounted reconfiguration signal are selected by the "wheel-mounted signal fault indicator". If the fault indicator is not true, the wheel-mounted signal is output; if the fault indicator is true, the wheel-mounted reconfiguration value signal is output.

[0035] (4) Delayed stability logic.

[0036] By using a two-state machine with a timer, the interference of instantaneous signal transitions on the wheel load output results is suppressed, thereby improving the stability of the judgment results.

[0037] The specific logic is as follows: if the wheel load comprehensive value is continuously unloaded (0) for n1 consecutive seconds, the wheel load output value is unloaded (0); if the wheel load comprehensive value is continuously loaded (1) for n2 consecutive seconds, the wheel load output value is loaded (1); if neither of the above two conditions is met, the wheel load output value is kept unchanged by the "keep previous value" module.

[0038] The advantages of this application include: This invention provides a safety protection method for aircraft wheel-borne signals. Using landing gear position signals and landing gear handle signals as preconditions, it logically protects the wheel-borne signals, effectively preventing dangerous wheel-borne signal malfunctions during flight. Using radio altitude, wheel speed, and airspeed signals to logically reconstruct the aircraft's grounding state serves as a backup in case of wheel-borne signal failure, effectively improving the accuracy of the flight control system's air / ground status judgment under wheel-borne failure conditions and ensuring the control performance of the flight control system. Using a two-state machine with a timer effectively suppresses interference from instantaneous signal jumps on the wheel-borne output results, improving the stability of the wheel-borne judgment results. Furthermore, the landing gear handle, landing gear lowered, and landing gear retracted signals used in the preconditions, as well as the radio altitude, wheel speed, and airspeed signals used in the reconstruction logic, are all from different sources than the wheel-borne signals, effectively avoiding common-mode faults with the wheel-borne signals. Finally, all of the above signals are conventional and common signals on modern aircraft. The protection logic provided by this invention can be implemented through software and algorithms without adding additional hardware, demonstrating good economic efficiency. In summary, this invention provides better safety protection against failure modes and abnormal conditions such as failure, error, and jump in aircraft wheel-borne signals, and improves the safety and stability of wheel-borne signals and aircraft air / ground status judgment, thus having high application value in the aviation and aerospace industries.

[0039] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for protecting aircraft wheel-mounted signals, characterized in that, include: The prerequisites for wheel load bearing signals are determined based on the landing gear lowering-in signal, the landing gear retraction-in signal, and the landing gear handle position signal. The protective wheel-mounted signal is determined based on the preconditions of the wheel-mounted signal and the original wheel-mounted signal; the wheel-mounted reconstruction signal when the aircraft wheel-mounted signal fails is synthesized based on the radio altitude, wheel speed and air speed signals. Based on the wheel-mounted signal fault marker, the wheel-mounted protection signal and the wheel-mounted reconfiguration signal are selected and output as the wheel-mounted comprehensive value signal; The wheel load bearing signal prerequisite is valid when any one of the following three conditions is true: the landing gear lowered to position signal is true, the landing gear retracted to position signal is false, or the landing gear handle lowered signal is true. The protection wheel load signal is valid when both the precondition for the wheel load signal and the original wheel load signal are valid. The specific methods for determining wheel-mounted reconfiguration signals include: The wheel-mounted reconfiguration signal is valid when the radio altitude is below the threshold, the wheel speed is above the threshold, and the indicated speed is below the threshold simultaneously. The selection of the wheel load composite value signal includes: when the wheel load signal fault mark is valid, the wheel load reconfiguration signal is used as the wheel load composite value signal; when the wheel load signal fault mark is invalid, the protection wheel load signal is used as the wheel load composite value signal. When the landing gear is in the lowered position signal is true or the landing gear is in the retracted position signal is false, the landing gear lowered status signal is valid; when the landing gear lowered status signal is valid or the landing gear handle position signal is lowered, the wheel load bearing signal prerequisite is valid.

2. The safety protection method for aircraft wheel-borne signals as described in claim 1, characterized in that, Before the wheel load composite value signal is output, the instantaneous jump of the wheel load composite value signal is suppressed by a two-state state machine with a timer, and then output as the wheel load output value.

3. The safety protection method for aircraft wheel-mounted signals as described in claim 1, characterized in that, The specific method for suppressing the instantaneous jump of the wheel load composite value signal includes: if the wheel load composite value signal is continuously invalid for n1 consecutive seconds, the wheel load output value is invalid; if the wheel load composite value is continuously valid for n2 consecutive seconds, the wheel load output value is valid; if neither of the above two conditions is met, the wheel load output value remains unchanged from its previous state.

Images