A comprehensive electronic equipment detonator impedance detection compensation method

Abstract

The application discloses a comprehensive electronic equipment detonator impedance detection compensation method, and aims at solving the technical problems that the existing comprehensive electronic equipment does not have a detonator impedance detection function, and the impedance detection precision is poor, the expected performance cannot be reached, and the detection difficulty is great. The application improves the detonator impedance test precision and the automation level, and realizes the engineering application of the detonator impedance detection function on the comprehensive electronic equipment. The method can also be popularized and applied to other occasions needing to detect the detonator impedance, and has certain guiding significance for engineering practice.

Description

Technical Field

[0001] This invention relates to a method for impedance detection and compensation of pyrotechnic devices, specifically a method for impedance detection and compensation of pyrotechnic devices in integrated electronic equipment. Background Technology

[0002] Pyrotechnics are commonly used in spacecraft launch systems. Ignition control methods for pyrotechnics are typically applied to applications such as thermal battery activation, engine ignition, and the ignition of explosive bolts in critical mechanical equipment. Generally, a control circuit provides current (either in-line or capacitor discharge) to ignite the pyrotechnic, which then heats up and ignites the firing mechanism. The success or failure of pyrotechnic ignition is crucial for spacecraft launches. If ignition fails, some circuits will lose power and malfunction, preventing spacecraft launch. Therefore, the safety and reliability of pyrotechnics are always a key focus for spacecraft launches. To ensure the safe and reliable operation of pyrotechnics, their impedance needs to be checked regularly. Traditional impedance checks typically involve manually measuring the impedance at both ends of the pyrotechnic. The impedance of pyrotechnics in spacecraft systems is relatively low, generally only 0.5Ω to 1.5Ω, and it varies significantly with temperature. Considering the impedance errors of cables in the system, the impedance testing accuracy for pyrotechnic channels is approximately 2Ω. In actual use, the impedance test accuracy for pyrotechnic circuits is required to be around 0.5Ω. If the impedance exceeds this range, the system will report a fault during self-test. If the required resistance of the ignition circuit (including cables and pyrotechnics) is greater than 5Ω or less than 0.5Ω (temperature range: -40℃~+60℃), a fault will be reported during self-test.

[0003] Integrated electronic systems (IES) address the new requirements of low cost, high integration, and versatility in future aircraft development. They integrate multiple individual units from traditional missile weapon systems, such as the main control computer and electronic ignition controller, to achieve functional integration. However, existing IES either lack pyrotechnic impedance detection capabilities or have poor impedance detection accuracy, failing to meet expected performance. A key challenge in IES design is how to integrate pyrotechnic impedance detection into IES to automate and intelligently perform the detection, and how to compensate for the impedance detection channels through algorithms to ensure accuracy, safety, and reliability. Summary of the Invention

[0004] The purpose of this invention is to provide a method for impedance detection and compensation of pyrotechnic components in integrated electronic equipment, so as to solve the technical problems that existing integrated electronic equipment does not have the function of impedance detection of pyrotechnic components, and the impedance detection accuracy is poor, fails to achieve the expected performance, and is difficult to detect.

[0005] To achieve the above objectives, the present invention provides a method for impedance detection and compensation of pyrotechnic components in integrated electronic equipment, characterized by the following steps:

[0006] Step 1: Using the pyrotechnic impedance acquisition circuit, the impedance of the nth pyrotechnic is acquired in real time through the pyrotechnic interface of the integrated electronic device to obtain the final test value Rsn of the nth pyrotechnic impedance, n = 1, 2, ... N;

[0007] Step 2: The host computer displays the final test value Rsn of the impedance of the nth pyrotechnic device in real time;

[0008] Step 3: Calculate the inherent impedance value Rgn of the nth interface terminal of the integrated electronic device using the following formula:

[0009] Rgn = Rgn1 - Rgn2;

[0010] in:

[0011] Rgn1 is the impedance value of the nth interface terminal of the integrated electronic device obtained by testing with a multimeter.

[0012] Rgn2 is the short-circuit impedance value when the two probes of the multimeter are shorted.

[0013] Step 4: Connect a standard resistor box to the interface terminal corresponding to the nth pyrotechnic device in Step 1 in the integrated electronic device to simulate the nth pyrotechnic device.

[0014] Adjust the resistance of the standard resistance box to RSn0; calculate the difference between the impedance output Rsn of the host computer and the resistance value RSn0 of the resistance box when the resistance value RSn0 is different, and take the average value as the impedance deviation Rbn of the nth pyrotechnic device.

[0015] Calculate the system test deviation Rcn of the impedance of the nth pyrotechnic device under standard test conditions, Rcn = Rbn - Rgn;

[0016] The impedance test compensation model is used to compensate the value displayed on the host computer software. The compensated value displayed on the host computer software is the actual impedance value R of the nth pyrotechnic device. The impedance test compensation model is as follows:

[0017] R = R N -R cn -R tn In the formula △T,

[0018] R Nn It is the final test value Rsn of the impedance of the pyrotechnic device obtained in step 1;

[0019] R tn The temperature compensation coefficient for the resistance of the nth pyrotechnic device;

[0020] △T is the difference between the temperature measured by the temperature sensor near the nth pyrotechnic device and the room temperature test temperature of the pyrotechnic device.

[0021] Step 5: Repeat steps 1-4 to complete the impedance detection of n-channel pyrotechnic devices.

[0022] Furthermore, it also includes the step of adjusting the compensation parameters, specifically:

[0023] If the displayed value after impedance compensation differs from the actual impedance value of the nth pyrotechnic device, the compensation parameter is adjusted to make the displayed value match the actual value; the compensation parameter is the difference between the test value and the actual value.

[0024] Furthermore, it also includes a cubic temperature compensation step, specifically:

[0025] The impedance of the pyrotechnic device was tested at high temperature, room temperature, and low temperature. A cubic fitting was performed on the impedance test values ​​to calculate the corresponding third-order temperature coefficient T. 3 T 2 T, and perform third-term temperature compensation of the impedance according to the following formula:

[0026] R = R N -R tn 3·T 3 -R tn 2·T 2 -R tn 1·TR tn 0

[0027] Among them, R tn 3 represents the cubic temperature coefficient of the nth pyrotechnic device, R tn 2 represents the quadratic temperature coefficient of the nth pyrotechnic device, R. tn 1 represents the temperature coefficient of the first term of the nth pyrotechnic device, R tn 0 represents the zero-order temperature coefficient of the nth pyrotechnic device.

[0028] Furthermore, it also includes a fifth-order temperature compensation step, specifically:

[0029] a) Power on the integrated electronic equipment at -40℃ and collect the impedance of the pyrotechnic device for 20 minutes;

[0030] b) The integrated electronic equipment was kept powered on, and the temperature chamber was raised from -40℃ to 60℃ at a rate of 1℃ / min. Impedance test data were continuously collected during the heating process.

[0031] c) After the integrated electronic equipment reaches 60°C, continue to keep it at that temperature for 20 minutes to collect impedance test data, and then power off the integrated electronic equipment.

[0032] d) Perform a fifth-order fitting on all collected impedance test data, calculate the fifth-order temperature coefficient, and perform fifth-order temperature compensation on the impedance. The compensation model is as follows:

[0033] R = R N -R tn 5·T 5 -R tn 4·T 4 -R tn 3·T 3 -R tn 2·T 2 -R tn 1·TR tn 0.

[0034] Furthermore, in the temperature compensation, the high temperature is 60°C; the low temperature is -40°C.

[0035] Furthermore, in step 4, the temperature sensor is model DS18B20.

[0036] Furthermore, the pyrotechnic impedance acquisition circuit includes a constant current source, an 18-bit ADC chip ADS8691, a reverse diode V1, a reverse diode V2, a resistor R1, a switch S1, a switch S2, and a switch S3.

[0037] The constant current source is connected to one end of resistor R1 via switch S1, to the anode of reverse diode V1 via switch S2, and to the anode of reverse diode V2 via switch S3.

[0038] The other end of the resistor R1 and the cathode of the reverse diode V1 are grounded;

[0039] The cathode of the reverse diode V2 is connected to the nth pyrotechnic device;

[0040] The nth pyrotechnic device is connected to an electronic control switch Q1.

[0041] The beneficial effects of this invention are:

[0042] This invention improves the accuracy and automation level of pyrotechnic impedance testing, enabling the engineering application of pyrotechnic impedance detection in integrated electronic devices. This method can also be extended to other applications requiring pyrotechnic impedance testing, providing valuable guidance for engineering practice. Attached Figure Description

[0043] Figure 1 This diagram illustrates the connection relationships between integrated electronic equipment and pyrotechnic devices.

[0044] Figure 2 A circuit diagram for acquiring the internal resistance and voltage of pyrotechnic components within an integrated electronic device;

[0045] Figure 3 Connection diagram for impedance detection and compensation system;

[0046] Figure 4 This is a flowchart of impedance detection and compensation. Detailed Implementation

[0047] This invention proposes a method for impedance detection and compensation of pyrotechnic components in integrated electronic equipment, which improves the accuracy and automation level of pyrotechnic impedance testing and realizes the engineering application of pyrotechnic impedance detection function in integrated electronic equipment.

[0048] This invention provides the following technical solution:

[0049] First, an impedance acquisition circuit was designed to acquire the impedance of pyrotechnic devices in real time; combined with... Figures 1-3 As shown, the pyrotechnic impedance acquisition circuit includes a constant current source, an 18-bit ADC chip ADS8691, a reverse diode V1, a reverse diode V2, a resistor R1, switches S1, S2, and S3. The constant current source is connected to one end of the resistor R1 via switch S1, to the input terminal of the reverse diode V1 via switch S2, and to the input terminal of the reverse diode V2 via switch S3. The other end of the resistor R1 and the output terminal of the reverse diode V1 are grounded. The reverse diode V2 is connected to the nth pyrotechnic device.

[0050] Secondly, an impedance display software was designed to display the impedance of pyrotechnic products in real time.

[0051] Furthermore, a compensation algorithm was designed to compensate for the impedance of the pyrotechnic device in real time; the value displayed on the host computer software after compensation is the actual impedance value of the pyrotechnic device channel. For example... Figure 4 As shown, the specific steps are as follows:

[0052] (1) Design an impedance acquisition circuit for pyrotechnic devices, such as Figure 2 As shown, the impedance of the pyrotechnic channel is acquired using a constant current source and an 18-bit ADC chip ADS8691. First, the constant current source current flows through the high-voltage reverse diode V2 to the pyrotechnic resistor Rs, and the voltage Vn of channel n is measured. Second, the constant current source current flows through the compensation diode V1 (same model as V1), and the diode compensation voltage Vv is measured. Finally, the constant current source flows through the compensation resistor R1, and the current compensation voltage Vi is measured. The final measured value of the pyrotechnic impedance is Rs≈R1*(Vn-Vv) / Vi.

[0053] (2) Design an impedance display software, such as Figure 3 As shown, the impedance of the pyrotechnic device is displayed in real time via a host computer. The software can write and export compensation parameters for the impedance of the pyrotechnic device.

[0054] (3) Use a multimeter to test the impedance value Rgn1 of the pyrotechnic interface of the integrated electronic device. Short-circuit the two probes of the multimeter and test the impedance value Rgn2 of the short-circuited probes. The inherent impedance value of the integrated electronic device is Rgn = Rgn1 - Rgn2.

[0055] (4) Figure 4 As shown, a standard resistance box (simulating pyrotechnic items 1...N) is connected to the port of the integrated electronic device that interfaces with the pyrotechnic item. The resistance value of the standard resistance box is adjusted, and the difference between the impedance output of the host computer and the resistance value of the resistance box is calculated for different resistance values. The average value is then used as the zero point for resistance compensation and subtracted in the host computer software algorithm. Specifically, the steps include the following:

[0056] a) At room temperature (25℃), the resistance value of the standard resistance box is set to 0Ω, 1.0Ω, 2.0Ω and 5.0Ω in sequence. The software displays the impedance value and records Ran1, Ran2, Ran3 and Ran4 under the four input conditions.

[0057] b) Subtract the output resistance values ​​of 0Ω, 1.0Ω, 2.0Ω, and 5.0Ω from Ran1, Ran2, Ran3, and Ran4 respectively to obtain the differences Rbn1, Rbn2, Rbn3, and Rbn4. Take the average value as the impedance deviation of the nth pyrotechnic device, Rbn = (Rbn1 + Rbn2 + Rbn3 + Rbn4) / 4. Subtract the inherent impedance value Rgn from Rbn to obtain the system test deviation Rcn under normal temperature conditions, Rcn = Rbn - Rgn.

[0058] c) Place the integrated electronic equipment in a high and low temperature chamber, and collect the impedance values ​​under high temperature (60℃) and low temperature (-40℃) conditions respectively, as in step (3), and calculate the impedance-related temperature coefficient R. t =(R 高温 -R 低温 ) / (60-(-40)).

[0059] d) Compensate the value displayed by the host computer software according to formula (4). The value displayed by the host computer software after compensation is the actual value of the impedance of the pyrotechnic channel.

[0060] The impedance test compensation model is shown in Formula 1:

[0061] R = R N -R cn -R tn ·△T………(4)

[0062] In the formula:

[0063] R is the final test value after compensation;

[0064] R N The value obtained from the initial test by the host computer;

[0065] R cn For each resistance impedance test, the fixed deviation value is n = 1...N;

[0066] R tn The resistance compensation coefficient for each path is n = 1...N.

[0067] T represents the product temperature, measured using a DS18B20 temperature sensor near the accelerometer. △T represents the temperature difference. The actual resistance compensation was performed at room temperature (25℃), therefore the measured resistance is the value at 25℃, △T = T - 25.

[0068] e) If the displayed value differs from the actual value after impedance compensation, the compensation parameters can be adjusted appropriately to make the test results match the actual values.

[0069] (5) If the temperature compensation accuracy of the impedance is not ideal, the impedance at high temperature, normal temperature and low temperature can be tested separately. The impedance test values ​​are fitted with a cubic term to calculate the third-order temperature coefficient. The following formula is used to perform cubic temperature compensation on the impedance. The compensation model is shown in Formula 5:

[0070] R = R N -R tn 3·T 3 -R tn 2·T 2 -R tn 1·TR tn 0………(5)

[0071] Where Rtn3, Rtn2, Rtn1, and Rtn0 are temperature coefficients obtained by fitting cubic terms, Rtn3 represents the cubic temperature coefficient of the nth pyrotechnic device, Rtn2 represents the quadratic temperature coefficient of the nth pyrotechnic device, Rtn1 represents the linear temperature coefficient of the nth pyrotechnic device, and Rtn0 represents the zero-order temperature coefficient of the nth pyrotechnic device. All temperature coefficients are obtained by fitting cubic parameters.

[0072] (6) To further improve the temperature compensation accuracy of impedance, a full-temperature measurement mode can be used to compensate the impedance parameters. The specific method is as follows:

[0073] a) After the temperature chamber is lowered to -40℃ and kept at that temperature for 1.5 hours, the product is powered on and impedance test data is collected for 20 minutes.

[0074] b) The product is powered on continuously. The temperature chamber rises from -40℃ to 60℃ at a rate of 1℃ / min. Data is collected throughout the entire heating process.

[0075] c) After the product temperature reaches 60℃, continue to keep it at that temperature for 20 minutes to collect impedance data, then power off the product.

[0076] d) Fit the impedance test value to the fifth term, calculate the fifth-order temperature coefficient, and perform fifth-order temperature compensation on the impedance according to formula (6).

[0077] R = R N -R tn 5·T 5 -R tn 4·T 4 -R tn 3·T 3 -R tn 2·T 2 -R tn 1·TR tn 0……(6)

[0078] In equations (5) and (6):

[0079] R N The impedance test value before compensation;

[0080] R is the measured impedance value after compensation;

[0081] R tn 5. R tn 4. R tn 3. R tn 2. R tn 1. R tn 0 represents the 5th to 1st temperature coefficient of impedance as a function of temperature;

[0082] T represents the product temperature, measured using a DS18B20 temperature sensor located near the accelerometer.

[0083] Experimental results show that, according to formula (1) for fixed-value temperature coefficient compensation, the impedance test accuracy reaches 0.1 to 0.2Ω; according to formula (2) for cubic fixed-point temperature coefficient compensation, the impedance test accuracy reaches 0.05 to 0.1Ω; and according to formula (3) for quintic full temperature coefficient compensation, the impedance test accuracy is better than 0.05Ω.

[0084] This invention addresses the challenges of impedance testing for pyrotechnic components in existing integrated electronic equipment by proposing a method for impedance testing and compensation of pyrotechnic components in integrated electronic equipment. This method improves the accuracy and automation level of pyrotechnic component impedance testing, enabling the engineering application of pyrotechnic component impedance testing functionality in integrated electronic equipment. This method can also be extended to other applications requiring pyrotechnic component impedance testing, providing valuable guidance for engineering practice.

[0085] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them. For those skilled in the art, modifications can be made to the specific technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. However, these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions protected by the present invention.

Claims

1. A method for impedance detection and compensation of pyrotechnic components in integrated electronic equipment, characterized in that, Includes the following steps: Step 1: Using a pyrotechnic impedance acquisition circuit, the impedance of the nth pyrotechnic device is acquired in real time through the pyrotechnic interface of the integrated electronic device to obtain the final test value Rsn of the nth pyrotechnic impedance, n=1, 2, ... N; the pyrotechnic impedance acquisition circuit includes a constant current source, an 18-bit ADC chip ADS8691, a reverse diode V1, a reverse diode V2, a resistor R1, switches S1, S2, and S3; the constant current source is connected to one end of the resistor R1 through switch S1, to the anode of the reverse diode V1 through switch S2, and to the anode of the reverse diode V2 through switch S3; the other end of the resistor R1 and the cathode of the reverse diode V1 are grounded; the cathode of the reverse diode V2 is connected to the nth pyrotechnic device; the nth pyrotechnic device is connected to an electronically controlled switch Q1; Step 2: The host computer displays the final test value Rsn of the impedance of the nth pyrotechnic device in real time; Step 3: Calculate the inherent impedance value Rgn of the nth interface terminal of the integrated electronic device using the following formula: Rgn = Rgn1 - Rgn2; in: Rgn1 is the impedance value of the nth interface terminal of the integrated electronic device obtained by testing with a multimeter; Rgn2 is the short-circuit impedance value when the two probes of the multimeter are shorted. Step 4: Connect a standard resistor box to the interface terminal corresponding to the nth pyrotechnic device in Step 1 in the integrated electronic device to simulate the nth pyrotechnic device. Adjust the resistance of the standard resistance box to RSn0; calculate the difference between the impedance output Rsn of the host computer and the resistance value RSn0 of the resistance box when the resistance value RSn0 is different, and take the average value as the impedance deviation Rbn of the nth pyrotechnic device. Calculate the system test deviation Rcn of the impedance of the nth pyrotechnic device under standard test conditions, Rcn = Rbn - Rgn; The impedance test compensation model is used to compensate the value displayed on the host computer software. The compensated value displayed on the host computer software is the actual impedance value R of the nth pyrotechnic device. The impedance test compensation model is as follows: R=R N -R cn -R tn • In the formula △T, R N It is the final test value Rsn of the impedance of the pyrotechnic device obtained in step 1; R tn The temperature compensation coefficient for the resistance of the nth pyrotechnic device; △T is the difference between the temperature measured by the temperature sensor near the nth pyrotechnic device and the room temperature test temperature of the pyrotechnic device. Step 5: Repeat steps 1-4 to complete the impedance detection of n-channel pyrotechnic devices; It also includes the step of adjusting the compensation parameters, specifically: If the displayed value after impedance compensation differs from the actual impedance value of the nth pyrotechnic device, the compensation parameter is adjusted to make the displayed value match the actual value; the compensation parameter is the difference between the test value and the actual value.

2. The method for impedance detection and compensation of pyrotechnic components in integrated electronic equipment according to claim 1, characterized in that, It also includes a cubic temperature compensation step, specifically: The impedance of the pyrotechnic device was tested at high temperature, room temperature, and low temperature. A cubic fitting was performed on the impedance test values ​​to calculate the corresponding third-order temperature coefficient T. 3 T 2 T, and perform third-term temperature compensation of the impedance according to the following formula: R= R N -R tn 3·T 3 -R tn 2·T 2 -R tn 1·T-R tn 0 Among them, R tn 3 represents the cubic temperature coefficient of the nth pyrotechnic device, R tn 2 represents the quadratic temperature coefficient of the nth pyrotechnic device, R. tn 1 represents the temperature coefficient of the first term of the nth pyrotechnic device, R tn 0 represents the zero-order temperature coefficient of the nth pyrotechnic device.

3. The method for impedance detection and compensation of pyrotechnic components in integrated electronic equipment according to claim 1, characterized in that, It also includes a fifth-order temperature compensation step, specifically: a) Power on the integrated electronic equipment at -40℃ and collect the impedance of the pyrotechnic device for 20 minutes; b) The integrated electronic equipment was kept powered on, and the temperature chamber was raised from -40℃ to 60℃ at a rate of 1℃ / min. Impedance test data were continuously collected during the heating process. c) After the integrated electronic equipment reaches 60°C, continue to keep it at that temperature for 20 minutes to collect impedance test data, and then power off the integrated electronic equipment. d) Perform fifth-order fitting on all collected impedance test data, calculate the fifth-order temperature coefficient, and perform fifth-order temperature compensation on the impedance. The compensation model is as follows: R= R N -R tn 5·T 5 -R tn 4·T 4 -R tn 3·T 3 -R tn 2·T 2 -R tn 1·T-R tn 0; Among them, R tn 5. R tn 4. R tn 3. R tn 2. R tn 1. R tn 0 represents the 5th to 1st temperature coefficient of impedance as a function of temperature.

4. The method for impedance detection and compensation of pyrotechnic components in integrated electronic equipment according to claim 2, characterized in that: In the temperature compensation, the high temperature is 60°C; the low temperature is -40°C.

5. The method for impedance detection and compensation of pyrotechnic components in integrated electronic equipment according to claim 4, characterized in that: In step 4, the temperature sensor is model DS18B20.

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