Intelligent auxiliary push rod system and method for fire extinguishing airplane
By using an intelligent assisted push stick system that combines sensors and controllers to calculate the assisted push stick force in real time, the problem of maneuvering firefighting aircraft during water drop has been solved, ensuring flight safety and pilot control, and improving the maneuverability and safety of firefighting aircraft.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-02-09
- Publication Date
- 2026-04-14
AI Technical Summary
The nose pitching moment of a firefighting aircraft during water drop is difficult for the pilot to effectively compensate for due to the rapid decrease in weight and change in center of gravity. Existing autopilots and automatic stick pushers cannot adapt to this special working condition, posing a safety hazard.
Design an intelligent assisted stick system that combines a stick control with a control force sensor, flap angle sensor, and normal overload sensor to calculate and provide assisted stick force in real time. This ensures that the system intervenes only when the pilot has permission and it is safe to do so, and incorporates multiple cut-off logics to ensure safety and reliability.
It achieves safety, intelligence, and reliability of the auxiliary stick system during water drop operations by firefighting aircraft, ensuring that the pilot always maintains control, avoiding operational errors and loss of attitude, and improving flight safety and handling quality.
Smart Images
Figure CN121849348A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of aviation flight control technology, specifically relating to a flight control assistance system and method for special operation aircraft, especially firefighting aircraft, which provides intelligent pitch control assistance during aircraft water drop operations. Background Technology
[0002] Firefighting aircraft, such as large amphibious firefighting aircraft, need to deliver large amounts of water precisely at low altitudes and speeds when carrying out forest firefighting missions. At the moment of water delivery, the aircraft's weight decreases dramatically in a very short time, and its center of gravity changes rapidly, generating a strong pitching moment. If this sudden torque is entirely compensated for manually by the pilot, it requires the pilot to apply a huge and precise push-stick force in a very short time, resulting in an extremely high control load. This can easily lead to untimely or excessive compensation, causing the aircraft to stall or lose attitude control, seriously threatening flight safety.
[0003] In the existing technology, there are some general aircraft trim or autopilot systems, but they are not designed for the special operating conditions of instantaneous and large disturbances, such as water dropping by firefighting aircraft. The response mode of general autopilots is too smooth and cannot cope with sudden changes in torque; while simple automatic stick devices may be too "mechanical" and "active" and intervene at the wrong time, conflicting with the pilot's control intentions and causing danger.
[0004] Therefore, there is an urgent need for an intelligent assisted stick system specifically designed for firefighting aircraft. This system should be able to sensitively detect the drastic changes in flight status caused by water droplets and provide timely and effective control assistance. It should also ensure that this assistance is "compliant" and "cooperative" with the pilot, and that its intervention and withdrawal must be absolutely safe and reliable, and must never deprive the pilot of their control. Summary of the Invention
[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide an intelligent auxiliary push rod system and method for firefighting aircraft. This system is capable of:
[0006] 1. Provided the pilot has given explicit permission (pre-positioning) and the aircraft is in a suitable flight condition, auxiliary functions may be safely accessed; 2. Based on the aircraft's current actual configuration (mainly reflected in the flap deflection angle) and the pilot's real-time control force input, the most suitable auxiliary push rod force is intelligently calculated; 3. Strictly limit the maximum level of assistance at different stages of flight to ensure that assistance actions are always within the range that the pilot can easily cover and reject; 4. Establish multiple, redundant safety disconnection logics to ensure that the auxiliary functions can be deactivated instantly and without residue when the pilot's intentions change or the system detects any anomalies.
[0007] The technical solution of this invention is implemented as follows: To achieve the above objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides an intelligent auxiliary push rod system for firefighting aircraft.
[0008] The system includes an auxiliary push rod controller, a control stick force sensor, an auxiliary push rod pre-position switch, a flap angle sensor, a normal overload sensor, and an auxiliary push rod actuator.
[0009] The control stick force sensor, auxiliary push rod pre-position switch, flap angle sensor, and normal overload sensor are all connected to the auxiliary push rod controller to provide real-time input signals.
[0010] The control end of the auxiliary push rod actuator is connected to the auxiliary push rod controller to receive control commands; its output end is mechanically coupled to the force sensing mechanism of the aircraft's control stick to output auxiliary force.
[0011] The auxiliary push rod controller is the core processing unit, and its internal programming implements the following functional modules and logic: 1. Function Enablement and Safety Monitoring Module: This module continuously reads the pre-position switch status and normal overload value. The auxiliary pushstick function enters the "Enable Ready" state only if two conditions are met simultaneously: ① The pre-position switch is actively pressed (activated) by the pilot; ② The value measured by the normal overload sensor is greater than a positive enable threshold (e.g., 2 m / s²), indicating that the aircraft is in a normal flight state with positive overload, rather than a state of weightlessness or severe maneuvering anomalies. Once in operating mode, this module continuously performs safety checks. If any of the following conditions are detected, a "forced disconnect" command is immediately issued: ① The pre-position switch is released (closed); ② The normal overload value drops to near or less than 0 (e.g., ≤0 m / s²); ③ Optionally, an additional actuator angle sensor detects that the actuator's own travel exceeds the safe mechanical limit. This multi-layered safety mechanism ensures the absolute priority and reliability of system exit.
[0012] 2. Configuration Recognition and Parameter Mapping Module: This module receives signals from the flap angle sensor. The system internally uses a pre-defined "flap angle - configuration category" lookup table. For example, flap angles can be divided into: 0-5 degrees for "cruise configuration," 5-20 degrees for "takeoff configuration," and above 20 degrees for "approach / landing configuration." Each configuration category is associated with a set of pre-defined "force calculation parameters," mainly including the "force gain coefficient K" and the "output force upper limit F_limit."
[0013] 3. Intelligent Calculation Module for Assisted Force Value: This module starts working when the system is enabled. It reads the control stick force sensor signal F_pilot in real time. The calculation process follows these steps: a. Baseline Force Calculation: Calculates the net control force required by the pilot beyond the baseline requirement, F_base = F_pilot - F_threshold. F_threshold is a preset activation threshold force (e.g., 100N) used to filter out minor, unconscious pilot movements or stick force sensor noise. The system only considers assistance necessary when the pilot is actually pushing the stick forward (F_pilot > F_threshold).
[0014] b. Configuration-related gain calculation: Based on the currently identified configuration category, extract the corresponding force gain coefficient K. Calculate the initial auxiliary force F_initial = F_base × K. The value of K varies under different configurations, reflecting different auxiliary strategies: cruise configuration (small K, such as 1 / 6), with the gentlest auxiliary response, mainly used for small trims between long-range cruises; takeoff configuration (medium K, such as 1 / 4), with a faster response; approach / landing configuration (large K, such as 1 / 3), with the fastest response, to cope with potentially more drastic attitude changes at low altitudes and low speeds.
[0015] c. Limiting the Assist Force: Compare the calculated F_initial with the upper limit of the output force corresponding to the current configuration, F_limit. Take the smaller of the two values as the final target assist force value, F_assist. That is, F_assist = min(F_initial, F_limit). This step is crucial, as it ensures that even in extreme situations, the assist force provided by the system will not exceed the preset safety limit for this flight phase (e.g., a cruise limit of 50N and a landing limit of 200N), and the pilot always retains the ability to easily cover this assist force.
[0016] 4. Command Output and Actuation Control Module: This module calculates the target auxiliary push stick force value F_assist, combines it with the actuator's force-current characteristics, and converts it into a specific drive command (such as current or PWM signal), which is then sent to the auxiliary push stick actuator. The actuator then generates a corresponding linear or rotational motion, which acts on the control stick force sensing mechanism through a mechanical linkage, applying a forward force to the control stick, thereby assisting the pilot in completing the push stick action.
[0017] Secondly, the present invention provides an intelligent auxiliary push rod control method for firefighting aircraft.
[0018] This method is executed by the airborne controller and specifically includes the following steps: S1: Signal Acquisition. Continuously acquires digital or analog signals from the pre-position switch, normal overload sensor, control stick force sensor, and flap angle sensor.
[0019] S2: Function Enable Judgment. Check if the preset switch is in the "on" state and if the normal overload value continuously exceeds the enable threshold for a set stabilization time (e.g., 0.5 seconds). If satisfied, the system enters the "auxiliary push rod working mode"; otherwise, it remains in the "standby mode".
[0020] S3: Configuration Recognition and Parameter Call. In the auxiliary push rod working mode, the current configuration category (such as cruise / takeoff / approach and landing) is determined by querying the preset mapping table based on the real-time flap angle, and the force gain coefficient K and output force limit F_limit bound to the configuration are called.
[0021] S4: Dynamic Calculation of Assist Force. The current control stick operating force F_pilot is acquired in real time. First, it is determined whether F_pilot is greater than the activation threshold F_threshold. If not, the output assist force is zero. If it is greater, the force is calculated using the formulas F_base = F_pilot - F_threshold and F_initial = F_base × K. Finally, the final command force value is obtained using F_assist = min(F_initial, F_limit).
[0022] S5: Instruction Execution and Output. Converts F_assist into actuator control instructions and outputs them.
[0023] S6: Parallel Safety Monitoring and Cut-off. This is an independent monitoring thread that runs in parallel with S3-S5. It continuously checks the safety cut-off conditions (preset switch closed, overload too low, actuator over-limit). Once any condition is met, this thread immediately issues the highest priority interrupt signal, the system unconditionally stops the current force value calculation and command output, exits the auxiliary push rod working mode, and the actuator is reset.
[0024] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. Extremely high safety: It adopts a dual enable condition of "pilot pre-positioning + status verification" and multiple redundant fast cut-off logic, which eliminates the system's false start and stickiness from the mechanism, and ensures the pilot's absolute control over the system.
[0025] 2. Intelligent Adaptation: The system does not provide a fixed amount of assistance force, but rather dynamically adjusts the intensity and priority of the assistance force based on the aircraft's current flight phase (reflected by flap configuration) and the pilot's real-time control intensity. This ability to "read between the lines" makes the assistance behavior highly aligned with actual flight needs.
[0026] 3. User-friendly human-machine collaboration: By setting configuration-related output force limits and calculation starting points based on pilot control forces, the system always plays the role of an "assistant." The assist force is always just a proportional increase in the pilot's control force, and its total amount is limited. The pilot can take the lead or terminate the assist process at any time by increasing or decreasing their own stick force, or by directly releasing the pre-position switch. The human-machine authority relationship is clear and reasonable.
[0027] 4. Highly targeted: Designed specifically for the instantaneous and high-load change conditions of water-dropping operations by firefighting aircraft, its response logic and parameter settings are closely aligned with the characteristics of this scenario, solving the problem of general systems being "unsuitable" or "unusable", effectively improving the safety of such special operations and the pilot's control quality.
[0028] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description
[0029] Figure 1 This is a schematic diagram of the principle architecture of the intelligent auxiliary push rod system of the present invention.
[0030] Figure 2 This is a logic diagram of the auxiliary push rod on / off judgment module of the present invention. Detailed Implementation
[0031] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of the embodiments of this invention will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The described embodiments are some embodiments of this invention, but not all embodiments.
[0032] The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the invention, and should not be construed as limiting the invention.
[0033] Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this invention.
[0034] The following is in conjunction with the appendix Figure 1-2 The embodiments of the present invention will be described in detail below.
[0035] Example 1 This invention discloses an intelligent auxiliary push rod system and method for firefighting aircraft.
[0036] System hardware composition and connection: refer to Figure 1 The hardware of the intelligent assisted push rod system in this embodiment includes: Auxiliary pushstick controller: It adopts a redundant flight control computer (FCC) that meets aviation standards and has multiple analog / digital input / output interfaces.
[0037] Sensor group: Control stick force sensor: Employs a miniature strain gauge force sensor, mounted on the push-pull linkage of the control stick, to measure the forward and backward stick forces applied by the pilot and output an analog voltage signal.
[0038] Flap angle sensor: Reuses the aircraft's original flap position indicator sensor (such as RVDT) to obtain the precise flap deflection angle.
[0039] Normal overload sensor: reuses normal overload (Nz) data provided by the aircraft inertial reference system (IRS) or the atmospheric data inertial reference system (ADIRS).
[0040] Auxiliary push rod actuator angle sensor (optional): mounted on the actuator output shaft to monitor the actuator stroke.
[0041] Human-machine interface: Auxiliary push-stick pre-position switch: A two-position self-locking button with an indicator light, mounted on the steering wheel or center console for easy thumb operation by the pilot. Pressing it illuminates the indicator light to indicate pre-position.
[0042] Implementing agency: Auxiliary pushrod actuator: An electric linear actuator (ELA) or rotary actuator, its housing fixed to the aircraft structure, with its output rod connected to the input rocker arm of the control stick force-sensing mechanism via a one-way clutch or flexible coupling. This connection ensures that the actuator can only apply force in the forward direction to the control stick, and that when the pilot pulls back on the stick, there is no reaction force from the actuator.
[0043] All sensor signals are connected to the corresponding input interfaces of the controller via cables. The status of the preset switch is read through the discrete input interface. The controller's output interface is connected to the actuator's motor via a power drive circuit.
[0044] Control software logic implementation: The controller's software operates within a defined period (e.g., 20ms). (Reference) Figure 2 The following main tasks are performed in each cycle: 1. Data update: Read all input signals, perform necessary filtering (such as first-order low-pass filtering) and validity checks.
[0045] 2. Enable and monitor tasks (high priority): Logic for judgment: IF (Preset switch == ON) AND (Nz>2.0 m / s²) THEN Enable flag = TRUEELSE Enable flag = FALSE.
[0046] Safety monitoring: IF (Enable flag == TRUE) AND (Preset switch == OFF OR Nz ≤ 0 m / s² OR Actuator angle > 30°) THEN Force disconnect flag = TRUE.
[0047] If the forced disconnect flag is TRUE, the enable flag and all internal calculation states are immediately cleared, and a "zero" command is sent to the actuator.
[0048] 3. Auxiliary computation tasks (executed only when the enable flag is TRUE): a. Configuration identification: Based on the current flap angle θ_flap: If θ_flap ≤ 5°, then the configuration is Config = CRUISE, with parameters K = 1 / 6 and F_limit = 50N.
[0049] If 5° < θ_flap ≤ 20°, then the configuration is Config = TAKE_OFF, parameter K = 1 / 4, F_limit = 100N.
[0050] If θ_flap > 20°, then the configuration is Config = APPROACH_LAND, with parameters K = 1 / 3 and F_limit = 200N. Approach and landing are combined here because both typically have large flap angles.
[0051] b. Force Calculation: Obtain the current lever force F_pilot. Let F_threshold = 100N.
[0052] If F_pilot ≤ 100N, then F_assist = 0N.
[0053] If F_pilot > 100N, then: F_base = F_pilot - 100 F_initial = F_base × K (K is the value corresponding to the current configuration) F_assist = min(F_initial, F_limit) (F_limit is the value corresponding to the current configuration) This calculation process ensures that the assist force increases smoothly and within bounds with the pilot's stick force.
[0054] 4. Command output task: Convert the calculated F_assist into the target current I_cmd according to the actuator's force-current calibration curve, and send it to the actuator through DA output or PWM drive circuit.
[0055] Typical work scenario simulation: Scenario 1: Preparations and Auxiliary Connections Before Water Release The aircraft is over the fire, flaps lowered to 25 degrees (approach configuration), preparing to drop water. After stabilizing its attitude, the pilot presses the auxiliary stick pre-position switch on the control panel with their thumb. At this time, the aircraft's normal overload Nz is approximately 1.2g (approximately 11.8 m / s², greater than the 2m / s² enable threshold). The controller detects "pre-position ON and Nz > threshold," sets the enable flag to TRUE, the system indicator light remains on, and the aircraft enters auxiliary standby mode. At this time, the pilot's stick force is 80N (less than the 100N threshold), therefore F_assist = 0N, and the actuator does not activate.
[0056] Scenario 2: Assistance work during water drop The pilot pressed the water release button, and water from the tank poured out within seconds. The aircraft's center of gravity shifted forward, generating a huge pitching moment, and the nose began to pitch up. Instinctively, the pilot forcefully pushed the control stick forward to counteract the pitch, and the stick force rapidly increased to 400N.
[0057] The system detected a rod force F_pilot = 400N > 100N.
[0058] The current configuration is APPROACH_LAND, K=1 / 3, F_limit=200N.
[0059] Calculate: F_base = 400 - 100 = 300N; F_initial = 300 × (1 / 3) = 100N; min(100, 200) = 100N.
[0060] The controller immediately instructs the actuator to output a 100N forward thrust assist. This is equivalent to helping the pilot bear about 1 / 3 of the extra stick load, enabling them to stabilize the aircraft's attitude more easily and accurately, avoiding rough handling or delayed reaction caused by excessive physical exertion.
[0061] Scenario 3: Safe disconnection of accessibility functions After the water drop is completed, the pilot pulls back on the stick to level the aircraft. At this point, the stick force decreases, and the assist force calculated by the system also decreases smoothly. Once the aircraft is level, the pilot actively releases the pre-position switch. The controller detects "pre-position OFF," immediately sets the enable flag to FALSE, stops all calculations, and instructs the actuators to return to zero at a gentle rate. The system completely disengages, returning full control to the pilot. Alternatively, if the aircraft unexpectedly enters a state of slight weightlessness (Nz close to 0) during the assist process, even if the pre-position switch is not released, the system will immediately and forcibly disconnect based on the condition Nz ≤ 0, ensuring that no incorrect assist is provided under abnormal attitude conditions.
[0062] In summary, this invention provides an intelligent, safe, and effective solution to the challenge of controlling water drop operations from firefighting aircraft through a highly integrated hardware and software system.
[0063] Example 2 This invention proposes a fire extinguisher auxiliary push rod system, which can provide corresponding auxiliary push rod values during the aircraft's water drop process for different flap configurations, ensuring both flight safety and flight performance.
[0064] A fire extinguisher auxiliary push rod system includes an auxiliary push rod controller, a control stick force sensor, an auxiliary push rod pre-position switch, an auxiliary push rod actuator, an auxiliary push rod actuator angle sensor, a control stick, a control stick force sensing mechanism, a flap angle sensor, and a normal overload sensor. The auxiliary push rod controller is connected to the control stick force sensing mechanism via the auxiliary push rod actuator. The control stick force sensor, auxiliary push rod pre-position switch, auxiliary push rod actuator angle sensor, flap angle sensor, and normal overload sensor are directly connected to the auxiliary push rod controller. The auxiliary push rod controller comprehensively determines whether to activate the auxiliary push rod function based on the auxiliary push rod pre-position switch, auxiliary push rod actuator angle sensor, and normal overload sensor, and issues an activation command to the auxiliary push rod actuator. The control stick force sensor and flap angle sensor determine the magnitude of the auxiliary push rod force value.
[0065] Furthermore, the auxiliary push rod controller has a built-in auxiliary push rod on / off judgment module and an auxiliary push rod force value calculation module. The auxiliary push rod on / off judgment module determines whether the auxiliary push rod function is on based on the signals from the auxiliary push rod pre-position switch, the auxiliary push rod actuator angle sensor, and the normal overload sensor. If so, it will send an on command to the auxiliary push rod actuator. The auxiliary pushstick force calculation module has built-in activation thresholds, command sizes, and command permissions for auxiliary pushstick commands under different aircraft wing configurations. The auxiliary pushstick force calculation module compares the control force value collected from the control stick force sensor with the activation threshold. If the control force value is greater than the activation threshold, the auxiliary pushstick force calculation module will issue a control command to the auxiliary pushstick actuator. If the control force value is less than or equal to the activation threshold, the auxiliary pushstick force calculation module will not issue a control command to the auxiliary pushstick actuator. The size of the control command is related to the control force value of the control stick force sensor, but does not exceed the prescribed command permissions.
[0066] Furthermore, if the auxiliary push rod on / off judgment module considers the auxiliary push rod function to be off, receives the auxiliary push rod pre-position switch to be open, and the signal from the normal overload sensor is greater than threshold 1, then it considers the auxiliary push rod function to be on; otherwise, it keeps the auxiliary push rod function off. If the auxiliary push rod on / off judgment module considers the auxiliary push rod function to be on, receives the auxiliary push rod pre-position switch to be closed, or the signal from the auxiliary push rod actuator angle sensor to threshold 2, or the signal from the normal overload sensor to threshold 3, then it considers the auxiliary push rod function to be off.
[0067] Furthermore, the auxiliary push rod force calculation module divides the flap configuration into cruise configuration, takeoff configuration, approach configuration, and landing configuration.
[0068] Furthermore, the auxiliary push rod force calculation module considers the flap to be in cruise configuration when the signal received from the flap angle sensor is less than or equal to threshold 4, in takeoff configuration when the signal received from the flap angle sensor is greater than threshold 4 and less than or equal to threshold 5, in approach configuration when the signal received from the flap angle sensor is greater than threshold 5 and less than or equal to threshold 6, and in landing configuration when the signal received from the flap angle sensor is greater than threshold 6.
[0069] Furthermore, when the auxiliary push rod force calculation module determines that the flap configuration is cruise configuration, the auxiliary push rod force value is the signal from the control stick force sensor minus threshold 7, then divided by 6, and the command authority is threshold 8. When the auxiliary push rod force calculation module determines that the flap configuration is takeoff configuration, the auxiliary push rod force value is the signal from the control stick force sensor minus threshold 7, then divided by 4, and the command authority is threshold 9. When the auxiliary push rod force calculation module determines that the flap configuration is approach configuration, the auxiliary push rod force value is the signal from the control stick force sensor minus threshold 7, then divided by 3, and the command authority is threshold 10. When the auxiliary push rod force calculation module determines that the flap configuration is landing configuration, the auxiliary push rod force value is the signal from the control stick force sensor minus threshold 7, then divided by 3, and the command authority is threshold 11.
[0070] Furthermore, when the auxiliary push rod actuator receives the on / off command from the auxiliary push rod on / off judgment module and the auxiliary push rod force value calculation module control command is greater than 0, it pushes the control rod forward through the control rod force sensing mechanism.
[0071] 1) This system is designed with different command sizes and permissions for different flap configurations of the aircraft, so that the command size and permission are matched with the aircraft status as much as possible, ensuring both flight safety and flight performance. 2) The auxiliary pushstick controller comprehensively determines whether to activate the auxiliary pushstick function through the auxiliary pushstick pre-position switch, the auxiliary pushstick actuator angle sensor, and the normal overload sensor, and issues an activation command to the auxiliary pushstick actuator. The magnitude of the auxiliary pushstick force value is determined by the control stick force sensor and the flap angle sensor.
[0072] Example 3 Referring to the attached drawings, the design configuration of the fire extinguisher auxiliary push rod system of this application is as follows. Figure 1 The device comprises an auxiliary push rod controller, a control stick force sensor, an auxiliary push rod pre-position switch, an auxiliary push rod actuator, an auxiliary push rod actuator angle sensor, a control stick, a control stick force sensing mechanism, a flap angle sensor, and a normal overload sensor. Its features include the following: the auxiliary push rod controller is connected to the control stick force sensing mechanism via the auxiliary push rod actuator; the control stick force sensor, auxiliary push rod pre-position switch, auxiliary push rod actuator angle sensor, flap angle sensor, and normal overload sensor are directly connected to the auxiliary push rod controller; the auxiliary push rod controller comprehensively determines whether to activate the auxiliary push rod function through the auxiliary push rod pre-position switch, auxiliary push rod actuator angle sensor, and normal overload sensor, and issues an activation command to the auxiliary push rod actuator; the control stick force sensor and flap angle sensor determine the magnitude of the auxiliary push rod force value.
[0073] The auxiliary push rod controller has a built-in auxiliary push rod on / off judgment module and an auxiliary push rod force value calculation module. The auxiliary push rod on / off judgment module determines whether the auxiliary push rod function is on based on the signals from the auxiliary push rod pre-position switch, the auxiliary push rod actuator angle sensor, and the normal overload sensor. If so, it will send an on command to the auxiliary push rod actuator.
[0074] The auxiliary pushstick force calculation module has built-in activation thresholds, command sizes, and command permissions for auxiliary pushstick commands under different aircraft wing configurations. The auxiliary pushstick force calculation module compares the control force value collected from the control stick force sensor with the activation threshold. If the control force value is greater than the activation threshold, the auxiliary pushstick force calculation module will issue a control command to the auxiliary pushstick actuator. If the control force value is less than or equal to the activation threshold, the auxiliary pushstick force calculation module will not issue a control command to the auxiliary pushstick actuator. The size of the control command is related to the control force value of the control stick force sensor, but does not exceed the prescribed command permissions.
[0075] If the auxiliary push rod on / off judgment module determines that the auxiliary push rod function is off, receives an open auxiliary push rod pre-position switch, and the signal from the normal overload sensor is greater than 2 m / s², then it considers the auxiliary push rod function to be on; otherwise, it keeps the auxiliary push rod function off. If the auxiliary push rod on / off judgment module determines that the auxiliary push rod function is on, receives a closed auxiliary push rod pre-position switch, or a signal from the auxiliary push rod actuator angle sensor greater than 30 degrees, or a signal from the normal overload sensor less than or equal to 0 m / s², then it considers the auxiliary push rod function to be off.
[0076] The auxiliary push rod force calculation module divides the flap configuration into cruise configuration, takeoff configuration, approach configuration, and landing configuration.
[0077] The auxiliary push rod force calculation module considers the flap to be in cruise configuration when the received signal from the flap angle sensor is less than or equal to 5 degrees, in takeoff configuration when the received signal is greater than 5 degrees and less than or equal to 20 degrees, in approach configuration when the received signal is greater than 20 degrees and less than or equal to 25 degrees, and in landing configuration when the received signal is greater than 25 degrees.
[0078] When the auxiliary push rod force calculation module determines that the flap configuration is cruise, the auxiliary push rod force is the signal from the control stick force sensor minus 100N, divided by 6, and the command authority is 50N. When the auxiliary push rod force calculation module determines that the flap configuration is takeoff, the auxiliary push rod force is the signal from the control stick force sensor minus 100N, divided by 4, and the command authority is 100N. When the auxiliary push rod force calculation module determines that the flap configuration is approach, the auxiliary push rod force is the signal from the control stick force sensor minus 100N, divided by 3, and the command authority is 150N. When the auxiliary push rod force calculation module determines that the flap configuration is landing, the auxiliary push rod force is the signal from the control stick force sensor minus 100N, divided by 3, and the command authority is 200N.
[0079] When the auxiliary push rod actuator receives the on / off command from the auxiliary push rod on / off judgment module and the control command from the auxiliary push rod force value calculation module is greater than 0, it pushes the control rod forward through the control rod force sensing mechanism.
[0080] Assumptions: The current state is as follows: the auxiliary push rod function is off, the auxiliary push rod pre-position switch is on, the normal overload sensor signal is 2.5 m / s², the auxiliary push rod actuator angle sensor signal is 0 degrees, the control stick force sensor signal is 100 N, the flaps are in cruise configuration, the auxiliary push rod on / off judgment module determines that the auxiliary push rod function is on, the auxiliary push rod force value calculation module control command is 0 N, and the auxiliary push rod actuator is not working.
[0081] Assumptions: The current state is as follows: the auxiliary push rod function is off, the auxiliary push rod pre-position switch is on, the normal overload sensor signal is 2.5 m / s², the auxiliary push rod actuator angle sensor signal is 0 degrees, the stick control force sensor signal is 500 N, the flaps are in cruise configuration, the auxiliary push rod on / off judgment module determines that the auxiliary push rod function is on, the auxiliary push rod force value calculation module control command is 50 N, and the auxiliary push rod actuator is working.
[0082] Assumptions: The current state is as follows: the auxiliary push rod function is on, the auxiliary push rod pre-position switch is open, the normal overload sensor signal is 0.5 m / s², the auxiliary push rod actuator angle sensor signal is 30 degrees, the stick control force sensor signal is 400 N, the flaps are in landing configuration, the auxiliary push rod on / off judgment module determines that the auxiliary push rod function is on, the auxiliary push rod force value calculation module control command is 100 N, and the auxiliary push rod actuator is working.
[0083] Assumptions: The current state is as follows: the auxiliary push rod function is on, the auxiliary push rod pre-position switch is on, the normal overload sensor signal is 0 m / s², the auxiliary push rod actuator angle sensor signal is 30 degrees, the control stick force sensor signal is 400 N, the flaps are in landing configuration, the auxiliary push rod on / off judgment module determines that the auxiliary push rod function is off, the auxiliary push rod force value calculation module control command is 100 N, and the auxiliary push rod actuator is not working.
[0084] Thus, the objective of this invention has been achieved.
[0085] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.
Claims
1. An intelligent auxiliary push rod system for firefighting aircraft, characterized in that, include: An auxiliary push rod controller, and a control stick force sensor, an auxiliary push rod pre-position switch, a flap angle sensor, and a normal overload sensor, all of which are respectively connected to the auxiliary push rod controller via signal. An auxiliary push rod actuator, the control end of which is connected to the auxiliary push rod controller, and the output end of which is mechanically coupled to the force sensing mechanism of the aircraft's control stick; The auxiliary push rod controller is configured to execute: Function enable judgment: Based on the state of the auxiliary push rod pre-position switch and the normal overload value monitored in real time by the normal overload sensor, determine whether to allow entry into the auxiliary push rod working mode; Assist force value decision: When in the assist push stick working mode, the control force value of the control stick control force sensor and the flap deflection angle of the flap angle sensor are collected in real time; The current aircraft configuration category is determined based on the flap deflection angle, and the target auxiliary push rod force value is calculated from the control force value according to the force value mapping rule corresponding to the configuration category; the force value mapping rule presets different force gain coefficients and output force upper limits for different configuration categories; Command output: The target auxiliary push rod force value is converted into a control command and sent to the auxiliary push rod actuator to drive it to act on the control stick force sensing mechanism and generate an auxiliary force to push the control stick forward.
2. The intelligent auxiliary push rod system for firefighting aircraft according to claim 1, characterized in that, The auxiliary push rod controller is also configured to perform a function safety disconnection judgment: Continuously monitor the status of the auxiliary push rod pre-position switch and the normal overload value of the normal overload sensor; The auxiliary push rod will immediately exit its operating mode and stop outputting control commands to the auxiliary push rod actuator when any of the following conditions are met: a) The auxiliary push rod pre-position switch is switched to the off state; b) The normal overload value is less than or equal to a preset lower overload threshold.
3. The intelligent auxiliary push rod system for firefighting aircraft according to claim 1 or 2, characterized in that, The auxiliary push rod actuator is equipped with an actuator angle sensor, and the actuator angle sensor is signal-connected to the auxiliary push rod controller; When the auxiliary push rod controller performs the functional safety cut-off judgment, it also monitors the angle value of the actuator angle sensor. When the angle value exceeds a preset angle safety threshold, it immediately exits the auxiliary push rod working mode.
4. The intelligent auxiliary push rod system for firefighting aircraft according to claim 1, characterized in that, The determination of the current aircraft configuration type based on the flap deflection angle specifically includes: Multiple consecutive flap angle ranges are preset, and each range corresponds to a configuration category; The real-time collected flap deflection angles are matched with the flap angle range to determine the configuration category. The configuration categories include at least: cruise configurations corresponding to small-angle flaps, takeoff configurations corresponding to medium-angle flaps, and approach and landing configurations corresponding to large-angle flaps.
5. The intelligent auxiliary push rod system for firefighting aircraft according to claim 4, characterized in that, In the force value mapping rule, the preset force gain coefficients are different for different configuration categories, specifically as follows: For the cruise configuration, the force gain coefficient is set to be the smallest, so that the auxiliary force response is the smoothest. For the takeoff configuration, the force gain coefficient is set to be greater than that for the cruise configuration; For approach and landing configurations, the force gain coefficient is set to the maximum, resulting in the fastest auxiliary force response.
6. The intelligent auxiliary push rod system for firefighting aircraft according to claim 5, characterized in that, In the auxiliary force value decision step, the general formula for calculating the target auxiliary push rod force value F_assist is: F_assist = min{ K * (F_pilot - F_threshold), F_limit} Where F_pilot is the real-time control force value, F_threshold is the preset control force start threshold, K is the force gain coefficient corresponding to the current configuration category, F_limit is the upper limit of the output force corresponding to the current configuration category; min indicates taking the smaller of the calculated value in parentheses and F_limit.
7. The intelligent auxiliary push rod system for firefighting aircraft according to claim 1, characterized in that, The logic for determining the function enable is as follows: The auxiliary push rod operating mode is allowed only if the auxiliary push rod pre-position switch is detected to be in the open state and the normal overload value is continuously greater than a preset overload enable threshold for a certain period of time.
8. A smart auxiliary push rod control method for firefighting aircraft, characterized in that, Performed by the airborne controller, the process includes the following steps: S1: Continuously collect auxiliary push rod pre-position switch status signal, normal overload signal, control stick operating force signal and flap angle signal; S2: Based on the pre-position switch state and normal overload signal, perform auxiliary push rod function enable logic judgment, and only enter the auxiliary push rod working mode when the enable condition is met; S3: In the auxiliary push rod working mode, based on the real-time collected flap angle signal, query the preset configuration-parameter mapping table to determine the current configuration category of the aircraft and its corresponding force value calculation parameter set. The parameter set includes at least the force gain coefficient and the upper limit of the output force. S4: Based on the real-time collected control stick force signal and the force value calculation parameter set, dynamically calculate the target auxiliary push rod force value required at the moment; S5: Convert the target auxiliary push rod force value into an actuator drive command and output it; S6: In the auxiliary push rod working mode, the safety monitoring logic is executed in parallel. If any of the following conditions are detected: the pre-position switch is closed, the normal overload is below the lower limit, or the actuator stroke exceeds the limit, the S4-S5 steps are interrupted immediately and the auxiliary push rod working mode is exited.
9. The intelligent auxiliary push rod control method for firefighting aircraft according to claim 8, characterized in that, In step S3, the configuration-parameter mapping table divides the flap angle into at least three intervals, corresponding to the three configuration categories of cruise, takeoff, and approach / landing, respectively; The approach / landing configurations share the same set of force calculation parameters.
10. The intelligent auxiliary push rod control method for firefighting aircraft according to claim 9, characterized in that, In step S4, the method for dynamically calculating the target auxiliary push rod force value is as follows: First, calculate the baseline demand force: F_base = current control force value - preset control force activation threshold; If F_base ≤ 0, then the target auxiliary push rod force value is 0; If F_base > 0, then calculate the initial auxiliary force: F_initial = F_base × force gain coefficient corresponding to the current configuration; Finally, F_initial is compared with the upper limit of the output force corresponding to the current configuration, and the smaller value is taken as the final target auxiliary push rod force value.