Unlocking mechanism force signal conditioning device and conditioning method

Abstract

The embodiment of the invention discloses an unlocking mechanism force signal conditioning device, which is characterized in that a signal conditioning unit comprises an input filter circuit, a pre-stage amplification circuit, a post-stage amplification circuit and a filter circuit which are connected in sequence, and can amplify weak millivolt-level signals output by a force measuring unit step by step and effectively filter the weak millivolt-level signals; noise interference introduced by a complex electromagnetic environment is suppressed, the accuracy and integrity of signal measurement are ensured, the defect that weak signals are prone to interference and attenuation is overcome, the temperature compensation circuit can dynamically compensate for zero drift generated by the sensor and the circuit along with temperature changes, and a stable reference provided by the power supply circuit unit is combined. And the problem of measurement misalignment caused by temperature drift is effectively relieved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of force measurement, and relates to an unlocking mechanism force signal conditioning device and a conditioning method. BACKGROUND

[0002] With the continuous progress of science and technology, aviation technology has developed rapidly, and the requirements for onboard equipment are miniaturization, integration, light weight, universality, good environmental adaptability, and electromagnetic environment and lightning environment guaranteeing product reliability and safety. As the sensing unit of the aircraft information acquisition system, the millivolt-level voltage signal output by the sensor is weak and cannot be directly collected by the RIU system, and is easily distorted and inaccurate due to environmental interference, affecting the measurement accuracy. SUMMARY

[0003] The application aims to solve the problem in the prior art that the signal cannot be directly collected by the RIU system, is easily distorted and inaccurate due to environmental interference, and affects the measurement accuracy, and provides an unlocking mechanism force signal conditioning device and a conditioning method.

[0004] To achieve the above-mentioned purpose, the application adopts the following technical solutions: The application discloses an unlocking mechanism force signal conditioning device, which utilizes a resistance strain type force sensor to detect the tensile and compressive force value of a cockpit cover unlocking electric mechanism and converts the tensile and compressive force value into a millivolt-level voltage signal, provides an excitation voltage for the voltage signal through a force signal conditioning control device, and processes the signal through amplification, filtering, temperature compensation, electromagnetic shielding, lightning protection, zero adjustment, full-range conditioning and the like, so as to convert the measured force value into a voltage signal and send the voltage signal to an RIU. The technical solution is that the force signal conditioning device is designed to be small in size and light in weight from the aspects of mechanical structure design, component selection, optimized circuit design and optimized PCB layout, so as to ensure that the size and weight of the force signal conditioning device meet the requirements. The system inputs a +15VDC±0.5VDC direct current power supply, and obtains a stable +10VDC through a lightning protection circuit, an overcurrent and overvoltage protection circuit, a pi filter circuit and a three-terminal voltage regulator, so as to provide an excitation voltage for the force sensor. The voltage signal converted by the force sensor is processed through a filtering circuit and a front-stage amplification circuit, and then is processed through a rear-stage amplification circuit and a second-order filter circuit, so as to send the signal to an airplane.

[0005] An unlocking mechanism force signal conditioning device comprises a force measurement unit, the force measurement unit is used for measuring the tensile and compressive force of a to-be-detected mechanism, and the output end of the force measurement unit is connected to the input end of a signal conditioning unit. The force measurement unit and the signal conditioning unit are both connected to a power supply circuit unit. The signal conditioning unit comprises an input filter circuit, a pre-amplification circuit, a temperature compensation circuit, a post-amplification circuit and a filter circuit connected in sequence, and the input end of the input filter circuit is connected with the output end of the force measuring unit.

[0006] The further improvement of the present application is that: The pre-amplification circuit comprises an instrument amplifier and a gain resistor connected in sequence.

[0007] The instrument amplifier is provided with a gain pin RG1 and a gain pin RG2, and the gain resistor is arranged between the gain pin RG1 and the gain pin RG2.

[0008] The temperature compensation circuit comprises a zero potential potentiometer, the first fixed end of the zero potential potentiometer is connected with a first thermistor, the other end of the first thermistor is connected with a fifteenth resistor R15, the other end of the fifteenth resistor R15 is connected with a power supply, the first thermistor is connected in parallel with a seventeenth resistor R17, the second fixed end of the zero potential potentiometer is connected with a second thermistor, the other end of the second thermistor is connected with a sixteenth resistor R16, the other end of the sixteenth resistor R16 is connected with a power supply, and the second thermistor PT2 or NT2 is connected in parallel with an eighteenth resistor R18. The sliding end of the potentiometer is connected with the instrument amplifier. The first thermistor and the second thermistor are PT resistors or NT resistors.

[0009] The power supply circuit unit comprises lightning protection circuit, short-circuit protection circuit, over-voltage protection circuit, π filter circuit and three-terminal voltage stabilizing circuit connected in sequence. The output ends of the three-terminal voltage stabilizing circuit are connected with the force measuring unit and the signal conditioning unit respectively. The signal conditioning unit comprises a box body, a printed board is arranged in the box body, and the input filter circuit, the pre-amplification circuit, the temperature compensation circuit, the post-amplification circuit and the filter circuit are integrated on the printed board. A metal cover plate is arranged on the box body. The force measuring unit is arranged outside the box body.

[0010] The force measuring unit is a force sensor.

[0011] The box body is mounted on the cockpit cover of an airplane.

[0012] The inner cavity of the box body and the metal cover plate are filled with a conductive rubber strip.

[0013] A force signal conditioning method for unlocking mechanism of the conditioning device comprises the following steps: A voltage signal of the tension and compression force of the unlocking electric mechanism of the cockpit cover of an airplane is acquired. The voltage signal is filtered by the input filter circuit and then enters the pre-amplification circuit, The preamplifier circuit amplifies the filtered voltage signal to obtain the preamplified signal. The temperature compensation circuit performs zero-point temperature compensation on the preamplified signal; The temperature-compensated signal is processed sequentially by a subsequent amplifier circuit and a second-order filter circuit to obtain a standard voltage signal.

[0014] Compared with the prior art, the present invention has the following beneficial effects: This invention discloses a force signal conditioning device for an unlocking mechanism. The signal conditioning unit includes an input filter circuit, a pre-amplifier circuit, a post-amplifier circuit, and a filter circuit connected in sequence. It can amplify and effectively filter the weak millivolt-level signal output by the force measuring unit step by step, suppress noise interference introduced by complex electromagnetic environment, ensure the accuracy and integrity of signal measurement, and overcome the defects of weak signals being susceptible to interference and attenuation. The temperature compensation circuit can dynamically compensate for the zero-point drift caused by temperature changes in the sensor and the circuit itself. Combined with the stable reference provided by the power supply circuit unit, it effectively alleviates the measurement inaccuracy problem caused by temperature drift.

[0015] Furthermore, in this invention, the force measuring unit is located outside the box, and the force measuring unit is integrated with the box of the force signal conditioning device. The space between the inner cavity of the box and the metal cover is filled with conductive rubber strips, which improves the overall sealing of the product and effectively enhances the electromagnetic protection capability. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the circuit principle of the invention; Figure 2 This is a schematic diagram of the invention. Figure 3 This is a schematic diagram of the circuit structure in the invention. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0019] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0020] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0021] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper," "lower," "horizontal," or "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. Furthermore, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0022] Furthermore, the use of the term "horizontal" does not imply that the component must be absolutely horizontal, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0023] In the description of the embodiments of the present invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention according to the specific circumstances.

[0024] The present invention will now be described in further detail with reference to the accompanying drawings: See Figures 1-3 This invention discloses a force signal conditioning device for unlocking mechanism, which is used to detect the force on the aircraft cockpit canopy and provide a basis for judging the locking and unlocking of the cockpit. The device has the characteristics of small size, strong anti-electromagnetic interference capability, high measurement accuracy, good temperature stability and high reliability.

[0025] This invention discloses a force signal conditioning device for an unlocking mechanism, used to process millivolt-level voltage signals output from a resistance strain gauge force sensor. This sensor is used to detect the tension and force of the aircraft cockpit canopy unlocking electric mechanism. The force signal conditioning device integrates key design functions such as analog signal conditioning, electromagnetic and lightning protection, miniaturization, and temperature compensation, converting the weak sensor signal into a standard voltage signal for use by the airborne system.

[0026] Specifically, the force signal conditioning device disclosed in this embodiment of the invention is a metal structure, and the elastic body and the housing of the force signal conditioning device are designed as an integrated unit in the mechanical structure design. The force sensor includes an elastic body, on the surface of which a Wheatstone bridge composed of strain gauge resistors is disposed, and a diaphragm for outputting voltage signals is disposed above the elastic body, and a signal conditioning unit receives the voltage signals. The force signal conditioning device includes a sealed housing with a metal cover on the outside. The space between the metal cover and the housing is filled with a conductive rubber strip. The internal printed circuit board assembly is used to output control signals. The printed circuit board assembly integrates an input filter circuit, a preamplifier circuit, a temperature compensation circuit, a postamplifier circuit, and a second-order filter circuit to output control signals.

[0027] To obtain a stable +10VDC excitation voltage, the input circuit is equipped with a lightning protection circuit, an overcurrent and overvoltage protection circuit, a π filter circuit, and a three-terminal regulator.

[0028] Furthermore, in this embodiment of the invention, the amplification factor of the pre-amplifier circuit and the post-amplifier circuit has sufficient margin, and the amplitude of the output signal can be adjusted by adjusting the corresponding components.

[0029] Furthermore, in this embodiment of the invention, an NTC or PTC resistor is added to the temperature compensation circuit to perform temperature compensation design on the zero-point adjustment circuit. Since the force sensor and force signal conditioning device experience zero-point drift under temperature changes, the zero-point adjustment circuit is significantly affected by temperature. By adding a temperature compensation circuit to the signal conditioning circuit, when the zero-point output voltage of the sensor channel (including the sensor's zero-point temperature drift) increases with temperature, the temperature compensation circuit is connected in series to the left end of the operational amplifier. As the temperature rises, the output voltage of the amplifier increases, the resistance of the temperature compensation resistor increases, and the voltage drop across the right side of the temperature compensation circuit decreases. The output voltage of the amplifier will decrease as the voltage drop across the right side of the temperature compensation circuit decreases. Conversely, when the voltage decreases with increasing temperature, only the temperature compensation resistor (NTC / PTC) needs to be soldered in series to the right end of the amplifier. The temperature coefficients and resistances of the two types of temperature compensation resistors (NTC / PTC) change with temperature differently; the soldering should be done according to the actual situation.

[0030] It should be noted that in this embodiment, the temperature compensation circuit can not only adjust the zero-position adjustment circuit, but also adjust other circuits in the force signal conditioning device when they are affected by temperature.

[0031] Furthermore, in this embodiment of the invention, the filtering circuit is specifically a filter composed of resistors, capacitors, and operational amplifiers, referred to as an active filter. The cutoff frequency of the RC active filter can be arbitrarily set by the RC network, and the network loss is compensated by the operational amplifier.

[0032] Example 1 This invention provides a force signal conditioning device for an unlocking mechanism. The sensor is used to detect the tension and force of the electric unlocking mechanism of an aircraft cockpit canopy. The force signal conditioning device integrates analog signal conditioning, electromagnetic / lightning protection, miniaturization, and temperature compensation, converting weak sensor signals into standard voltage signals for use by the airborne system. The principle of the device is as follows: Figure 1 As shown, it includes: A force signal conditioning device for unlocking mechanisms includes a force measuring unit for measuring the tension and compression of the mechanism under test. The output of the force measuring unit is connected to the input of a signal conditioning unit. Both the force measuring unit and the signal conditioning unit are connected to a power supply circuit unit. The signal conditioning unit includes an input filter circuit, a preamplifier circuit, a temperature compensation circuit, a postamplifier circuit, and a filter circuit connected in sequence.

[0033] Furthermore, in this embodiment of the invention, in the power supply circuit, the input signal is connected to a thermistor, which is connected to the pin of a diode (rectifier diode). The signal flows into a π-type filter circuit, which includes a capacitor and an inductor. The π-type filter circuit is connected to a three-terminal voltage regulator. A decoupling capacitor is placed near the power supply pin of the three-terminal voltage regulator to suppress conducted interference on the power line and output a stable +10VDC excitation voltage. In addition, a bidirectional TVS diode is used as a lightning protection device, with one end connected to the signal output cable and the other end connected to the housing (the housing is connected to the chassis).

[0034] In this embodiment of the invention, the π-type filter circuit performs high- and low-frequency filtering on the power supply, suppressing transient signals such as surges and improving the power supply's anti-interference capability; the three-terminal voltage regulator can reduce the power consumption of the force sensor and force signal processor, reduce the current flowing through the strain gauge, reduce heat loss, and improve the reliability of the strain gauge.

[0035] Furthermore, in this embodiment of the invention, the signal conditioning circuit mainly consists of an input filter circuit, a pre-amplifier circuit, a post-amplifier circuit, a temperature compensation circuit, and a second-order filter circuit, specifically: Preamplifier circuit: The preamplifier circuit consists of an instrumentation amplifier and a gain resistor. The millivolt-level voltage signal output from the force sensor's push-pull force is filtered by differential-mode and common-mode filtering, then input to pins 2 and 3 of the instrumentation amplifier. After amplification, the voltage signal is output from pin 6. The preamplifier circuit gain is designed to be 303 times (adjustable). See [link to relevant documentation] Figure 3 .

[0036] Post-amplifier circuit: The post-amplifier circuit is composed of a high-precision rail operational amplifier, precision metal film resistors, multilayer ceramic dielectric capacitors, and a full-range adjustable potentiometer. The output signal of the pre-amplifier circuit is connected to pin 3 of the operational amplifier, amplified again, and output from pin 1 of the operational amplifier. The gain of the post-amplifier circuit is designed to be 3.66 times (in this embodiment, the gain can be adjusted according to the actual situation).

[0037] Temperature compensation circuit: The core of the temperature compensation circuit is a platinum thin-film thermistor. The force sensor and force signal conditioning device will experience positive or negative zero-point drift under temperature changes. (See [link / reference]). Figure 3 In this embodiment of the invention, solder pads are reserved at the pins at both ends of the zero-position potentiometer for selectively mounting thermistors. The soldering position of the resistor is determined based on the measured temperature drift data of the product, utilizing the characteristic of its resistance changing with temperature to dynamically compensate the zero-position circuit.

[0038] Furthermore, since force sensors and force signal conditioning devices experience zero-point drift under temperature changes, compensation wires are typically used to compensate for the temperature of the force sensor. The zero-point potentiometer is the component in the force signal conditioning device most significantly affected by temperature. Therefore, in this printed circuit board design, an NTC / PTC thermistor pad is reserved at each end of the zero-point potentiometer. Based on the actual temperature drift of the product, NTC / PTC thermistors are selected and soldered on both sides of the zero-point potentiometer to perform temperature compensation design for the zero-point adjustment circuit (based on the characteristics of thermistor resistance changing with temperature), reducing the impact of temperature variations on product accuracy.

[0039] In this embodiment, when the current in the thermistor control circuit exceeds the operating circuit (operating current is 0.5A), the power supply is automatically cut off to prevent damage to the system power supply and protection signal conditioning circuit.

[0040] Filtering circuit: The filter circuit consists of resistors, capacitors, and an operational amplifier. The second-stage amplified signal flows into the operational amplifier after passing through the second-order filter circuit. After data processing, the signal is output from the pins of the operational amplifier. The filtered signal is buffered, isolated, and impedance matched. The operational amplifier is also connected to a current-limiting resistor, which limits the output current and isolates the load from the output of the integrated operational amplifier.

[0041] In this embodiment, a second-order low-pass active filter is used in the filtering circuit. To prevent the filtered output signal from being affected by changes in external load impedance, a voltage follower is added to buffer, isolate, and improve load capacity. An operational amplifier and a current-limiting resistor R12 are added to the output of the circuit. This isolates the load from the output of the integrated operational amplifier, limiting the output current of the operational amplifier, and also limits the amplitude of the output voltage. Since the bandwidth of the operational amplifier is maximum when the gain is 1, a resistor to determine the gain is not required, allowing a second-order low-pass active filter to be implemented with fewer components.

[0042] In this embodiment, in addition to using a filter circuit, a filter cover is installed at the interface during circuit design. The circuit is of type C, and the product has strong anti-electromagnetic interference capability.

[0043] Lightning protection circuit: In this embodiment of the invention, a bidirectional TVS diode is designed between the output circuit and the housing.

[0044] The core of the lightning protection circuit is a transient voltage suppressor diode (TVS). It is selected based on the instrumentation amplifier's maximum withstand voltage of +36VDC and the power supply voltage (+15±0.5VDC). The electrical parameters are: VBR≈18.3V, VC≈26V, VRWM≈16V, IP≈115.4A, PTVS =3000W. A transient voltage suppressor diode is added between the current limiting resistor and the output terminal to prevent excessive reverse current.

[0045] Furthermore, during the printed circuit board design, trace lengths were minimized, and high-current isolation was implemented. High-current power supply lines were routed separately with wider trace diameters and located away from sensitive signal grounds to prevent high-current fluctuations from affecting weak signals. Differential routing was employed; millivolt-level signals at the Wheatstone bridge input used equal-length, equidistant, and parallel differential pairs to reduce the conversion of differential-mode interference into common-mode interference. Ground lines were inserted between signal lines for isolation. Grounding copper strips or shielding frames were placed along the PCB edges and connected to the casing ground to enhance PCB edge shielding.

[0046] Specifically, this embodiment discloses a circuit diagram of the force signal conditioning device, see [link to diagram]. Figure 3 ,include: The first branch of the inverting input of the operational amplifier is connected to the seventeenth capacitor C17, the second branch is connected to the sixteenth capacitor C16, and the third branch is connected to the eighth resistor R8. The other end of the eighth resistor R8 is connected to the seventh resistor R7, and the other end of the seventh resistor R7 is grounded. The first branch of the non-inverting input of the operational amplifier is connected to the other end of the seventeenth capacitor C17, the second branch is connected to the nineteenth capacitor C19, and the third branch is connected to the thirteenth resistor R13. The other end of the thirteenth resistor R13 is connected to the fourteenth resistor R14, and the other end of the fourteenth resistor R14 is grounded. The other ends of the sixteenth capacitor C16 and the nineteenth capacitor C19 are both grounded. The first zero-adjustment terminal of the operational amplifier is connected to the third resistor R3, and the other end of the third resistor R3 is connected to the compensation terminal of the operational amplifier; one of the positive power supply terminals of the operational amplifier is connected to the power supply, and the other is connected to the fifteenth capacitor C15, and the other end of the fifteenth capacitor C15 is grounded. The first branch of the negative power supply terminal of the operational amplifier is connected to the power supply, and the second branch is connected to the twenty-first capacitor C21. The other end of the twenty-first capacitor C21 is grounded. The first branch of the second zero-adjustment terminal of the operational amplifier is connected to the positive power supply terminal of operational amplifier B, and the second branch is connected to the negative power supply terminal of operational amplifier B. The first branch of the inverting input terminal of operational amplifier B is connected to the power supply, and the second branch is connected to the twenty-second capacitor C22. The other end of the twenty-second capacitor C22 is grounded. The first branch of the output terminal of operational amplifier B is connected to the power supply, and the second branch is connected to the twenty-third capacitor C23. The other end of the twenty-third capacitor C23 is grounded. The non-inverting input terminal of operational amplifier B is connected to the sliding terminal of the zero-position potentiometer. The first fixed terminal of the zero-position potentiometer is connected to the first thermistor PT1 or NT1. The other end of the first thermistor PT1 or NT1 is connected to the fifteenth resistor R15. The other end of the fifteenth resistor R15 is connected to the power supply. The seventeenth resistor R17 is connected in parallel with the first thermistor PT1 or NT1. The second fixed terminal of the zero-position potentiometer is connected to the second thermistor PT2 or NT2. The other end of the second thermistor PT2 or NT2 is connected to the sixteenth resistor R16. The other end of the sixteenth resistor R16 is connected to the power supply. The eighteenth resistor R18 is connected in parallel with the second thermistor PT2 or NT2. The output of the operational amplifier is connected to the twelfth resistor R12. The other end of the twelfth resistor R12 is connected to the non-inverting input of operational amplifier A1. The first branch of the inverting input of operational amplifier A1 is connected to the fifth resistor R5, the other end of which is grounded. The second branch is connected to the fifty-first resistor R51. The other end of the fifty-first resistor R51 is connected to the fourth resistor R4, the sixth resistor R6, and the second sliding resistor. The first branch of the output of operational amplifier A1 is connected to the fourth resistor R4, the sixth resistor R6, and the other end of the second sliding resistor. The second branch is connected to the tenth resistor R10. The first branch of the other end of the tenth resistor R10 is connected to the thirteenth capacitor C13. The second branch is connected to the eleventh resistor R11. The other end of the thirteenth capacitor C13 is connected to the inverting input of operational amplifier A2. The first branch of the other end of the eleventh resistor R11 is connected to the non-inverting input of operational amplifier A2. The second branch is connected to the twentieth capacitor C20, the other end of which is grounded.

[0047] Example 2 This embodiment discloses a method for conditioning the force signal of an unlocking mechanism, including the following steps: The voltage signal of the tension and force of the aircraft cockpit canopy unlocking electric mechanism is obtained by a force sensor, and then a millivolt-level voltage signal is output. After differential-mode and common-mode filtering, the voltage signal enters the pre-amplifier circuit to amplify the voltage signal. Then, the amplified signal is temperature-compensated by the temperature compensation circuit. The compensated signal enters the post-amplifier circuit for amplification, and then enters the filter circuit for filtering to obtain the standard voltage signal.

[0048] In terms of mechanical structure, this design adopts an integrated solution, combining the elastomer and the force signal conditioning device into a housing. An external metal cover is added, and a conductive rubber strip seals the cover to the housing. This design not only improves the overall sealing performance of the product but also effectively enhances its electromagnetic protection capabilities.

[0049] To suppress zero-point drift caused by temperature, the temperature compensation circuit was optimized. Pads were provided at both ends of the zero-point potentiometer for mounting thermistors, enabling precise positive or negative temperature compensation for the zero-point adjustment circuit and improving the product's accuracy and stability across the entire temperature range.

[0050] In PCB layout, key measures such as optimizing routing rules, inserting ground lines for isolation between signal lines, and reinforcing PCB edges effectively suppress parasitic inductance and electromagnetic interference, ensuring signal integrity.

[0051] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A force signal conditioning device for an unlocking mechanism, characterized in that, It includes a force measuring unit, which is used to measure the tensile and compressive forces of the mechanism under test, and the output of the force measuring unit is connected to the input of the signal conditioning unit; Both the force measuring unit and the signal conditioning unit are connected to the power supply circuit unit; The signal conditioning unit includes an input filter circuit, a preamplifier circuit, a temperature compensation circuit, a postamplifier circuit, and a filter circuit connected in sequence. The input terminal of the input filter circuit is connected to the output terminal of the force measuring unit.

2. The force signal conditioning device for an unlocking mechanism according to claim 1, characterized in that, The preamplifier circuit includes a connected instrumentation amplifier and a gain resistor.

3. The force signal conditioning device for an unlocking mechanism according to claim 2, characterized in that, The instrumentation amplifier is provided with a gain pin RG1 and a gain pin RG2, and the gain resistor is set between the gain pin RG1 and the gain pin RG2.

4. The force signal conditioning device for an unlocking mechanism according to claim 2, characterized in that, The temperature compensation circuit includes a zero-position potentiometer. The first fixed terminal of the zero-position potentiometer is connected to a first thermistor. The other end of the first thermistor is connected to a fifteenth resistor R15. The other end of the fifteenth resistor R15 is connected to a power supply. A seventeenth resistor R17 is connected in parallel with the first thermistor. The second fixed terminal of the zero-position potentiometer is connected to a second thermistor. The other end of the second thermistor is connected to a sixteenth resistor R16. The other end of the sixteenth resistor R16 is connected to a power supply. An eighteenth resistor R18 is connected in parallel with the second thermistor PT2 or NT2. The sliding end of the potentiometer is connected to the instrumentation amplifier; The first thermistor and the second thermistor are PT resistors or NT resistors.

5. The force signal conditioning device for an unlocking mechanism according to claim 1, characterized in that, The power supply circuit unit includes a lightning protection circuit, a short circuit protection circuit, an overvoltage protection circuit, a π filter circuit, and a three-terminal voltage regulator circuit connected in sequence. The output terminals of the three-terminal voltage regulator circuit are connected to the force measuring unit and the signal conditioning unit, respectively.

6. The force signal conditioning device for an unlocking mechanism according to claim 1, characterized in that, The signal conditioning unit includes a housing, and a printed circuit board is disposed inside the housing. The input filtering circuit, the preamplifier circuit, the temperature compensation circuit, the postamplifier circuit and the filtering circuit are integrated on the printed circuit board. A metal cover is provided on the box body; The force measuring unit is located on the outside of the box.

7. The force signal conditioning device for an unlocking mechanism according to claim 6, characterized in that, The force measuring unit is a force sensor.

8. The force signal conditioning device for an unlocking mechanism according to claim 7, characterized in that, The box is installed on the aircraft cockpit canopy.

9. A force signal conditioning device for an unlocking mechanism according to claim 7, characterized in that, The space between the inner cavity of the box and the metal cover is filled with a conductive rubber strip.

10. A method for conditioning the force signal of the unlocking mechanism of the conditioning device according to claim 1, characterized in that, Includes the following steps: Obtain the voltage signal of the tension and compression of the aircraft cockpit canopy unlocking electric mechanism; The input filter circuit filters the voltage signal before it enters the preamplifier circuit. The preamplifier circuit amplifies the filtered voltage signal to obtain the preamplified signal. The temperature compensation circuit performs zero-point temperature compensation on the preamplified signal; The temperature-compensated signal is processed sequentially by a subsequent amplifier circuit and a second-order filter circuit to obtain a standard voltage signal.

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