Total distance rod force detection system and method

Abstract

The invention discloses a total distance rod force detection system and method. The total distance rod force detection system comprises five sensors and a data processing module signal box. The five sensors are respectively arranged on a front cabin force sensing collective distance rod, a rear cabin force sensing collective distance rod, a left front booster input force sensing pull rod, a left rear booster input force sensing pull rod and a right front booster input force sensing pull rod; the data processing module signal box comprises a power supply circuit, a signal conditioning circuit, an analog-to-digital conversion circuit, a main control unit circuit, a communication interface circuit and a level conversion circuit; the power supply circuit is connected with the signal conditioning circuits, the analog-to-digital conversion circuit, the main control unit circuit, the communication interface circuit and the five sensors, the five sensors are respectively connected with one signal conditioning circuit, the five signal conditioning circuits are all connected to the analog-to-digital conversion circuit, and the analog-to-digital conversion circuit is sequentially connected with the main control unit circuit and the communication interface circuit. The device can measure the value of force applied to the collective distance rod by a pilot, and feeds back a signal to a flight parameter acquisition system in real time.

Description

Technical Field

[0001] The present invention belongs to the field of flight control systems and relates to a collective pitch lever force detection system and method. Background Art

[0002] During the flight of a helicopter, the pilot mainly controls the ascending and descending movements, forward, backward (left and right), and pitching (or rolling) movements of the aircraft through the collective pitch control lever and cyclic pitch control lever, and completes flight actions such as takeoff, climb, cruise, descent, and landing during the execution of tasks.

[0003] In the current helicopter control system, there are fixed mechanical structures in the transmission path, such as: the front cabin force-sensing collective pitch lever, the rear cabin force-sensing collective pitch lever, the left front booster input force-sensing pull rod, the left rear booster input force-sensing pull rod, and the right front booster input force-sensing pull rod. However, there is no detection system to collect, filter, temperature compensate, process data, and report flight parameters to the flight parameter acquisition system in the form of bus transmission for the force conditions of each mechanical structure. Summary of the Invention

[0004] The purpose of the present invention is to overcome the above-mentioned disadvantages of the prior art and provide a collective pitch lever force detection system and method, which can measure the force values applied by the pilot on the collective pitch lever and cyclic pitch lever and feedback the signals to the flight parameter acquisition system in real time.

[0005] To achieve the above purpose, the present invention adopts the following technical solutions: A collective pitch lever force detection system includes five sensors and a data processing module signal box; The five sensors are respectively arranged on the front cabin force-sensing collective pitch lever, the rear cabin force-sensing collective pitch lever, the left front booster input force-sensing pull rod, the left rear booster input force-sensing pull rod, and the right front booster input force-sensing pull rod; The data processing module signal box includes a power supply circuit, a signal conditioning circuit, an analog-to-digital conversion circuit, a main control unit circuit, a communication interface circuit, and a level conversion circuit; The power supply circuit is connected to the signal conditioning circuit, the analog-to-digital conversion circuit, the main control unit circuit, the communication interface circuit, and the five sensors. Each of the five sensors is connected to a signal conditioning circuit, and the five signal conditioning circuits are all connected to the analog-to-digital conversion circuit. The analog-to-digital conversion circuit is sequentially connected to the main control unit circuit and the communication interface circuit.

[0006] Preferably, the level conversion circuit is connected to the main control unit circuit and the communication interface circuit, and the communication interface circuit is connected to the flight parameter acquisition system.

[0007] Preferably, the power supply circuit includes a power supply protection circuit, a power supply filtering circuit, a power supply module, a three-terminal voltage regulator, and a reference voltage source connected in sequence.

[0008] Preferably, the power protection circuit includes an anti-reverse connection circuit, a short-circuit protection circuit, and an overvoltage protection circuit.

[0009] Preferably, the signal conditioning circuit includes a filter circuit, a first-stage amplifier circuit, a second-stage amplifier circuit, and a second-order active filter circuit connected in sequence.

[0010] Preferably, the first-stage amplifier circuit includes an instrumentation amplifier, a bias circuit, a precision metal film resistor, and a temperature compensation circuit; the second-stage amplifier circuit includes an operational amplifier, a precision metal film resistor, and a capacitor.

[0011] Preferably, the communication interface circuit uses an external crystal oscillator and communicates with the main control unit circuit through the SPI bus.

[0012] Preferably, the data processing module signal box includes a box body. Two connection sockets are arranged on the box body. The two connection sockets are respectively connected to the flight parameter acquisition system and five sensors. A cover plate is arranged on the box body, and an analog-to-digital signal acquisition board and a digital signal processing board are arranged inside the box body.

[0013] A method for detecting the total pitch rod force includes the following processes: The force signals of the front cabin force-sensing total pitch rod, the rear cabin force-sensing total pitch rod, the left front booster input force-sensing pull rod, the left rear booster input force-sensing pull rod, and the right front booster input force-sensing pull rod are respectively collected by five sensors and output as millivolt-level voltages. The five-way sensor signals are amplified, filtered, and zero-temperature compensated through the signal conditioning circuit. The analog signals are converted into digital quantities through the analog-to-digital conversion circuit. The data is transmitted to the main control unit circuit for data parsing, data processing, and data frame encapsulation, and is sent to the flight parameter acquisition system through the communication interface circuit and the level conversion circuit.

[0014] Preferably, the 3.3V voltage output by the acquisition power supply circuit is collected, and the main control unit circuit detects the power supply state fault according to the collected voltage value.

[0015] Compared with the prior art, the present invention has the following beneficial effects: The present invention can measure the force values applied by the driver on the collective pitch control lever (front and rear), and at the same time measure the force values on the three booster input pull rods, and transmit them to the flight parameter acquisition system, realizing the amplification, filtering, A / D conversion, data parsing, and ARINC429 bus communication of the sensor output signals, and detecting the states of aircraft pitch, roll, and elevation through the magnitudes of the values, providing operation data for flight operation state and flight fault judgment. Description of the Drawings

[0016] Figure 1Schematic diagram of the collective pitch lever force detection system of the present invention.

[0017] Figure 2 Electrical cross - connection diagram of the collective pitch lever force detection system of the present invention.

[0018] Figure 3 Exploded view of the signal box structure of the data processing module of the present invention; Figure 4 Flow chart of the collective pitch lever force detection using the signal box of the data processing module of the present invention.

[0019] Wherein: 1 - cover plate; 2 - analog - digital signal acquisition board; 3 - digital signal processing board; 4 - box body; 5 - connection socket. Specific implementation mode

[0020] The following describes in detail the implementation mode of the present invention. Examples of the implementation mode are shown in the drawings, where the same or similar reference numerals indicate the same or similar elements or elements with the same or similar functions from beginning to end. The implementation mode described below by referring to the drawings is exemplary and is only used to explain the present invention and cannot be understood as a limitation of the present invention.

[0021] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by terms such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of the said features. In the description of the present invention, "a plurality" means two or more unless otherwise specifically defined.

[0022] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terms "mounted", "connected" and "coupled" shall be construed broadly, for example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection, an electrical connection or a communication connection; it may be directly connected, or indirectly connected through an intermediate medium, and it may be the internal communication of two components or the interaction relationship between two components. The term "and / or" used herein includes any and all combinations of one or more of the related listed items. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. The terms used in the description of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0023] In the present invention, unless otherwise clearly defined and limited, the first feature being "on" or "under" the second feature may include direct contact between the first and second features, or may include indirect contact between the first and second features through additional features therebetween. Moreover, the first feature being "above", "over" and "on top of" the second feature includes the first feature being directly above and obliquely above the second feature, or merely indicating that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "below" and "beneath" the second feature includes the first feature being directly below and obliquely below the second feature, or merely indicating that the horizontal height of the first feature is lower than that of the second feature.

[0024] The following disclosure provides many different embodiments or examples for implementing different structures of the present invention. To simplify the disclosure of the present invention, components and arrangements of specific examples are described below. Of course, they are only examples and are not intended to limit the present invention. In addition, the present invention may repeat reference numerals and / or reference letters in different examples. This repetition is for the purpose of simplification and clarity and does not in itself indicate the relationship between the various embodiments and / or arrangements discussed. In addition, the present invention provides examples of various specific processes and materials, but those of ordinary skill in the art may be aware of the application of other processes and / or the use of other materials.

[0025] As Figure 1 shown, the collective pitch lever force detection system described in the present invention includes five sensors and a data processing module signal box.

[0026] Five sensors are respectively arranged on the front cabin force-sensing collective pitch control lever, the rear cabin force-sensing collective pitch control lever, the left front booster input force-sensing pull rod, the left rear booster input force-sensing pull rod, and the right front booster input force-sensing pull rod. The five rods are modified into sensors. Specifically, strain gauges are pasted and grouped into bridges on the front cabin force-sensing collective pitch control lever, the rear cabin force-sensing collective pitch control lever, the left front booster input force-sensing pull rod, the left rear booster input force-sensing pull rod, and the right front booster input force-sensing pull rod. Each group of sensors consists of multiple strain gauges to form a Wheatstone bridge, constituting five rod force sensors. When the force-sensing pull rod is subjected to a control force, the control force causes the elastic body to undergo elastic deformation, resulting in a resistance change in the resistance strain gauge pasted thereon, which is used to measure the force values applied by the pilot to the collective pitch control lever and the cyclic pitch control lever. Then, the strain signal is converted into a millivolt-level voltage signal through the Wheatstone bridge.

[0027] The data processing module signal box is used to provide excitation voltage for the five groups of sensors of the 5 sensors, and amplify, filter through the hardware circuit, perform zero-point temperature compensation, synchronously collect data, detect faults, calibrate sensor data, analyze data, process data, convert the voltage into a force value, and send the force direction, force value, and fault information of the five rod force sensors to the flight parameter acquisition system in the form of the ARINC429 bus.

[0028] The data processing module signal box mainly includes a power supply circuit, a signal conditioning circuit, an analog-to-digital conversion circuit, a main control unit circuit, a level conversion circuit, and a communication interface circuit.

[0029] The power supply circuit part is mainly composed of a power supply protection circuit, a power supply filter circuit, a power supply module, a three-terminal voltage regulator, and a reference voltage source. The power supply protection circuit mainly includes an anti-reverse connection circuit, a short-circuit protection circuit, an over-voltage protection circuit, etc. The power supply circuit filters, performs anti-reverse connection processing, short-circuit protection processing, and voltage conversion processing on the power supply provided by the host, provides excitation voltage for the five groups of sensors, and provides working voltage, reference voltage, fault judgment voltage, etc. for other circuits. The data processing module signal box processes the +28VDC power supply voltage, filters it using an EMI power filter, and then processes it by a DC / DC power supply module to obtain power supply voltages of ±15VDC and +5VDC. The ±15VDC power supply voltage is obtained as ±12VDC through a three-terminal voltage regulator, +5V is obtained as 3.3V through a linear voltage regulator, and 5V is obtained as +2.5V through a reference voltage source to provide a reference voltage for the AD chip. Among them, the sensors are powered by +12VDC, the instrumentation amplifier and the operational amplifier are powered by ±12VDC, the main control unit is powered by +5VDC, the analog-to-digital converter is powered by +5VDC, ±12VDC, and a 2.5V reference voltage, and the communication interface circuit is powered by 3.3VDC.

[0030] The signal conditioning circuit mainly consists of an amplification circuit, a filtering circuit, a zero-temperature compensation circuit, etc. It collects, amplifies, and filters (removing high-frequency signals) the 5-channel sensor signals and 1 group of fault signals, and simultaneously performs temperature compensation on the zero output of the sensor.

[0031] After the signal conditioning circuit filters out the differential-mode and common-mode interferences of the sensor input signal through the filtering circuit, it is a first-stage amplification circuit composed of an instrumentation amplifier, a bias circuit, precision metal film resistors, and a temperature compensation circuit, which has temperature compensation, adjustable gain, and zero adjustment. The second-stage amplification circuit is composed of an operational amplifier, precision metal film resistors, capacitors, etc. The second-order active filtering circuit amplifies and filters the voltage value amplified by the second stage.

[0032] The temperature compensation circuit is composed of an operational amplifier, precision metal film resistors, capacitors, and temperature compensation resistors (PTC and NTC). After being isolated by the operational amplifier, it is connected to the V of the first-stage amplification circuit. REF When the signal box of the data processing module is affected by high temperature and the product output becomes larger, the PTC temperature compensation resistor is welded on the left side of the operational amplifier. Conversely, when the output becomes larger due to low temperature, the PTC temperature compensation resistor is welded on the right side of the operational amplifier. The working principle of the NTC is opposite to that of the PTC.

[0033] The filtered voltage is input to the analog-to-digital conversion circuit to start data conversion. The data is transmitted to the main control unit circuit through SPI communication for data parsing, data processing (filtering the 5-channel 20-group data collected by using the sliding filtering algorithm, and converting and calibrating the filtered data between voltage and force value by using the calibration function), and data frame encapsulation. Through the communication interface circuit and the level conversion circuit, it communicates with the flight parameter acquisition system using the ARINC429 bus and sends the data to the flight parameter acquisition system.

[0034] The communication interface circuit uses an external crystal oscillator, communicates with the main control unit circuit through the SPI bus, and completes the communication with the flight parameter acquisition system through the transceiver of the ARINC429 bus, realizing the transceiver of the force value signal of the stick force sensor.

[0035] The level conversion circuit realizes the level conversion between the main control unit circuit and the communication interface circuit. It is an automatic direction sensing voltage transmission circuit, which realizes the level conversion between 8 A ports and B ports through two separately configurable paths. It has fast speed, wide voltage range, and supports the open-drain mode.

[0036] Such as Figure 2As shown, the data processing module signal box is powered and cross-linked with the flight parameter acquisition and recording system through an electrical connector and transmits ARINC429 data. It also provides excitation voltage for the front cabin force-sensing collective pitch lever, rear cabin force-sensing collective pitch lever, left front booster input force-sensing pull rod, left rear booster input force-sensing pull rod, and right front booster input force-sensing pull rod through the electrical connector and collects and processes the force measurement signals.

[0037] As Figure 3 shown, the data processing module signal box includes a box body 4. There are two connection sockets 5 on the box body 4, which are respectively connected to the flight parameter acquisition system and five sensors. There is a cover plate 1 on the box body 4. Inside the box body, there is an analog-digital signal acquisition board 2 and a digital signal processing board 3. The analog-digital signal acquisition board 2 includes a power supply circuit, a first-stage amplification circuit, a second-stage amplification circuit, a filtering circuit, and a temperature compensation circuit. The digital signal processing board 3 includes an analog-digital conversion circuit, a main control unit circuit, a communication interface circuit, and a level conversion circuit. It collects, processes, frames, and uploads the sensor signals to the flight parameter acquisition system, separates the analog signals and digital signals, effectively reduces mutual electromagnetic interference, and ensures the accuracy of the signals.

[0038] Detect the states of aircraft pitch, roll, and altitude through the magnitude of the values, provide control data for flight control state and flight fault judgment, and improve the reliability of the flight control system during flight.

[0039] The collective pitch lever force detection system of the present invention has 6-channel data synchronous acquisition and conversion. Among them, 5 channels are the force values measured by 5 sensors (for force value conversion), and the other 1 channel of the analog-digital conversion circuit collects the 3.3V voltage converted by the power supply circuit. The main control unit circuit can directly detect the power supply faults of the power supply circuit and the communication circuit according to the collected voltage value, set the threshold according to the code value inside the AD corresponding to the 3.3V voltage. During power-on self-check, when the power supply voltage fails, it will cause the threshold to be inconsistent with the time voltage, and the product reports a fault. The product has complete functions, high integration, accurate measurement, and has the ability to detect faults.

[0040] The collective pitch lever force detection system adds a temperature compensation circuit in the signal conditioning circuit. When the zero output voltage value of the 5 sensor channels (including the zero temperature drift of the sensor) increases with the increase of temperature, the temperature compensation circuit is connected in series to the left end of the operational amplifier. When the temperature increases, the output voltage value of the amplification circuit increases, the resistance value of the temperature compensation resistor becomes larger, the voltage division value on the right side of the temperature compensation circuit decreases, and the output voltage value of the amplification circuit will decrease with the decrease of the voltage division value on the right side of the temperature compensation circuit. Conversely, when the voltage value decreases with the increase of temperature, only need to weld the temperature compensation resistor in series on the right end of the amplifier.

[0041] The collective pitch lever force detection system can, through the upper computer operation interface, query and calibrate the outputs of five sensors at zero position, quarter full scale, and full scale. The output curve of the sensors is fitted with three groups of data to reduce errors and improve product accuracy.

[0042] The collective pitch lever force detection system can amplify, filter, perform A / D conversion, data parsing, and ARINC429 bus communication on the output signal of the sensor, and feedback the signal to the flight parameter acquisition system in real time.

[0043] As Figure 4 shown, the collective pitch lever force detection process is as follows: First, initialization is performed to configure various I / Os, peripherals, clocks, interrupts, etc. Then, power-on self-check is carried out. After the power-on self-check is completed, it enters the loop process. Each loop process is a communication cycle. In one cycle, first, A / D acquisition is performed to convert the analog signal into a digital signal, then software filtering is carried out to filter out interference data, and then data processing is performed to calculate the sensor force signal and encapsulate the data according to the data frame format required by the ICD file. Finally, periodic communication is carried out to send the data frame to the flight parameter acquisition system in the form of ARINC429 bus. After sending is completed, wait for the timer to overflow and then start the next periodic communication.

[0044] The present invention can measure the force value applied by the driver on the collective pitch lever, and at the same time measure the force values on the input pull rods of three boosters. Data processing and temperature compensation are performed on the measured values, and they are transmitted to the flight parameter acquisition system in the form of ARINC429 bus (the data is in Newton unit). The states of the aircraft's pitch, roll, and altitude are detected through the magnitude of the values, providing operation data for flight operation state and flight fault judgment.

[0045] The serial numbers of the above embodiments of the present application are only for description and do not represent the advantages or disadvantages of the embodiments.

[0046] In the above embodiments of the present application, the descriptions of each embodiment have their own emphases. For the parts not detailed in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0047] In the several embodiments provided by the present application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only illustrative. For example, the division of the units can be a logical function division. In actual implementation, there can be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the couplings or direct couplings or communication connections shown or discussed with each other can be through some interfaces, and the indirect couplings or communication connections of the units or modules can be in electrical or other forms.

[0048] The unit described as a separating component may or may not be physically separated. The component shown as a unit may or may not be a physical unit, that is, it may be located in one place or may be distributed over multiple units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0049] The above are only the preferred embodiments of the present application. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present application, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present application.

[0050] It should be understood that the above description is for illustrative purposes and not for limitation. Many embodiments and many applications other than the examples provided will be apparent to those skilled in the art upon reading the above description. Therefore, the scope of this patent should not be determined by reference to the above description, but should be determined by reference to the full scope of the foregoing claims and the equivalents thereof. For the sake of completeness, all articles and references, including patent applications and published announcements, are incorporated herein by reference. The omission of any aspect of the subject matter disclosed herein in the foregoing claims is not intended to abandon such subject matter, nor should it be considered that the applicant has not considered such subject matter as part of the disclosed inventive subject matter.

Claims

1. A collective pitch lever force detection system, characterized in that, It includes five sensors and a signal box of the data processing module; The five sensors are respectively arranged on the front cabin force sensing collective pitch control lever, the rear cabin force sensing collective pitch control lever, the left front booster input force sensing pull rod, the left rear booster input force sensing pull rod, and the right front booster input force sensing pull rod; The signal box of the data processing module includes a power supply circuit, a signal conditioning circuit, an analog-to-digital conversion circuit, a main control unit circuit, a communication interface circuit, and a level conversion circuit; The power supply circuit is connected to the signal conditioning circuit, the analog-to-digital conversion circuit, the main control unit circuit, the communication interface circuit, and the five sensors. Each of the five sensors is connected to a signal conditioning circuit, and the five signal conditioning circuits are all connected to the analog-to-digital conversion circuit. The analog-to-digital conversion circuit is sequentially connected to the main control unit circuit and the communication interface circuit.

2. The collective pitch lever force detection system according to claim 1, wherein The level conversion circuit is connected to the main control unit circuit and the communication interface circuit, and the communication interface circuit is connected to the flight parameter acquisition system.

3. The collective pitch lever force detection system according to claim 1, wherein The power supply circuit includes a power supply protection circuit, a power supply filtering circuit, a power supply module, a three-terminal voltage regulator, and a reference voltage source that are sequentially connected.

4. The collective pitch lever force detection system according to claim 3, characterized in that, The power supply protection circuit includes an anti-reverse connection circuit, a short-circuit protection circuit, and an overvoltage protection circuit.

5. The collective pitch lever force detection system according to claim 1, wherein The signal conditioning circuit includes a filtering circuit, a first-stage amplification circuit, a second-stage amplification circuit, and a second-order active filtering circuit that are sequentially connected.

6. The collective pitch lever force detection system according to claim 5, characterized in that The first-stage amplification circuit includes an instrumentation amplifier, a bias circuit, a precision metal film resistor, and a temperature compensation circuit; the second-stage amplification circuit includes an operational amplifier, a precision metal film resistor, and a capacitor.

7. The collective pitch lever force detection system according to claim 1, characterized in that, The communication interface circuit uses an external crystal oscillator and communicates with the main control unit circuit through the SPI bus.

8. The collective pitch lever force detection system according to claim 1, wherein The signal box of the data processing module includes a box body (4). Two connection sockets (5) are arranged on the box body (4). The two connection sockets (5) are respectively connected to the flight parameter acquisition system and the five sensors. A cover plate (1) is arranged on the box body (4), and an analog-digital signal acquisition board (2) and a digital signal processing board (3) are arranged inside the box body.

9. A method for detecting the collective pitch lever force of the system according to any one of claims 1-8, characterized in that, It includes the following processes: The force signals of the front cabin force sensing collective pitch control lever, the rear cabin force sensing collective pitch control lever, the left front booster input force sensing pull rod, the left rear booster input force sensing pull rod, and the right front booster input force sensing pull rod are respectively collected by the five sensors, and a millivolt-level voltage is output; The five-way sensor signals are amplified, filtered, and zero-point temperature compensated through the signal conditioning circuit; The analog signal is converted into a digital quantity through the analog-to-digital conversion circuit; The data is transmitted to the main control unit circuit for data parsing, data processing, and data frame encapsulation, and the data is sent to the flight parameter acquisition system through the communication interface circuit and the level conversion circuit.

10. The collective pitch lever force detection method according to claim 9, characterized in that, The 3.3V voltage output by the power supply circuit is collected, and the main control unit circuit detects the power supply state fault according to the collected voltage value.

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