A method for measuring the ignition resistance of an industrial electronic detonator

Abstract

This invention provides a method for measuring the ignition resistance of an industrial electronic detonator, belonging to the field of resistance measurement technology. The method includes: measuring the ignition resistance of an industrial electronic detonator based on a detection circuit, wherein the detection circuit includes: an MCU microcontroller U1, a single-pole double-throw physical relay U2, a relay switching transistor Q1, voltage divider resistors R1 and R2 in the measurement circuit, and a dual-channel integrated operational amplifier; switching the test state of the ignition resistance based on the single-pole double-throw physical relay U2 and the relay switching transistor Q1; outputting a weak millivolt-level signal to the measurement circuit based on the MCU microcontroller U1 to control the specific voltage values ​​at points A and B corresponding to voltage divider resistors R1 and R2 under different test states; amplifying the specific voltage values ​​at points A and B by the dual-channel integrated operational amplifier at the same multiple, thereby calculating the current value flowing through the measurement circuit and calculating the ignition resistance value, effectively ensuring measurement accuracy.

Description

Technical Field

[0001] This invention relates to the field of resistance measurement technology, and in particular to a method for measuring the ignition resistance of an industrial electronic detonator. Background Technology

[0002] With rapid economic development, my country's infrastructure construction has also progressed by leaps and bounds. Digital electronic detonators are widely used in blasting operations in fields such as tunnel excavation, dilapidated building renovation, and geological exploration. Due to their superior cost-effectiveness and safety, digital electronic detonators have gradually replaced traditional electric detonators and detonating cords. In industrial electronic detonators, the ignition resistor is a crucial electronic component. Its main function is to generate an electric spark through the discharge of the energy storage capacitor, thereby igniting the ignition charge in the detonator head. Ignition resistors come in various types and shapes. From a resistance perspective, they can be defined as small resistors ranging from 2Ω to 10Ω, and these resistors can only handle a working current of no more than 3mA; otherwise, they risk burning out.

[0003] First, based on the characteristics of the ignition resistor mentioned above, how to measure the tiny resistance value within 10Ω has always been a technical challenge in the civil explosives industry; second, electronic detonators are civil pyrotechnics, and the measurement current has strict requirements to ensure the safety of the measurement; third, the ignition resistor is closely related to the propellant it is matched with, and in order to reliably detonate, the resistance measurement error must be guaranteed to be no more than 5%.

[0004] Therefore, this invention proposes a method for measuring the ignition resistance of industrial electronic detonators. Summary of the Invention

[0005] This invention provides a method for measuring the ignition resistance of an industrial electronic detonator, thereby solving the aforementioned technical problems.

[0006] This invention provides a method for measuring the ignition resistance of an industrial electronic detonator, comprising:

[0007] The measurement of the ignition resistance of an industrial electronic detonator is based on a detection circuit, which includes: an MCU microcontroller U1, a single-pole double-throw physical relay U2, a relay switching transistor Q1, voltage divider resistors R1 and R2 of the measurement circuit, and a dual-channel integrated operational amplifier.

[0008] Test status based on the switching of ignition resistor by single-pole double-throw physical relay U2 and relay switching transistor Q1;

[0009] Based on the MCU microcontroller U1, a weak signal at the millivolt level is output to the measurement circuit to control the specific voltage values ​​of points A and B corresponding to voltage divider resistors R1 and R2 under different test conditions.

[0010] The specific voltage values ​​at points A and B are amplified by the same factor using a dual-channel integrated operational amplifier, thereby calculating the current value flowing through the measurement circuit and the ignition resistance value.

[0011] Preferably, the dual-channel integrated operational amplifier includes: integrated operational amplifier U3 and integrated operational amplifier U4;

[0012] The specific connection method of the detection circuit is as follows: pin 1 of the MCU microcontroller U1 is connected to one end of the voltage divider resistor R1; pin 2 of the MCU microcontroller U1 is connected to the input terminal of the integrated operational amplifier U3; the output terminal of the integrated operational amplifier U3 is connected to one end of the voltage divider resistor R1; pin 3 of the MCU microcontroller U1 is connected to the input terminal of the integrated operational amplifier U4; and the output terminal of the integrated operational amplifier U4 is connected to the other end of the voltage divider resistor R1.

[0013] Pin 4 of the MCU microcontroller U1 is connected to the base of the relay switching transistor Q1, and the collector of the relay switching transistor Q1 is connected to pin 8 of the single-pole double-throw physical relay U2.

[0014] Pin 1 of the single-pole double-throw physical relay U2 is connected to the power supply VCC; pin 3 of the single-pole double-throw physical relay U2 is connected to the other end of the voltage divider resistor R1; pin 6 of the single-pole double-throw physical relay U2 is connected to one end of the voltage divider resistor R2; pin 4 of the single-pole double-throw physical relay U2 is connected to the VB terminal of the ignition resistor RX; pin 5 of the single-pole double-throw physical relay U2 is connected to the VX terminal of the ignition resistor RX; pins 2 and 7 of the single-pole double-throw physical relay U2 are short-circuited.

[0015] The third terminals of the integrated operational amplifiers U3 and U4 are respectively grounded, and the emitter of the relay switching transistor Q1 and the other end of the voltage divider resistor R2 are respectively grounded.

[0016] Preferably, the test status of the ignition resistor includes: bypass ignition resistor status and connected ignition resistor status.

[0017] Preferably, when the test state is the bypass ignition resistor state, the connection method of the corresponding equivalent circuit for the bypass ignition resistor state is as follows:

[0018] Pin 1 of the MCU microcontroller U1 is connected to one end of the voltage divider resistor R1. Pin 2 of the MCU microcontroller U1 is connected to the input terminal of the integrated operational amplifier U3. The output terminal of the integrated operational amplifier U3 is connected to one end of the voltage divider resistor R1. Pin 3 of the MCU microcontroller U1 is connected to the input terminal of the integrated operational amplifier U4. The output terminal of the integrated operational amplifier U4 is connected to the other end of the voltage divider resistor R1. The other end of the voltage divider resistor R1 is connected to one end of the measuring circuit resistance Rd. The other end of the measuring circuit resistance Rd is connected to one end of the voltage divider resistor R2.

[0019] The third terminals of the integrated operational amplifiers U3 and U4 are respectively grounded, and the other terminal of the voltage divider resistor R2 is grounded.

[0020] Preferably, when the test state is the ignition resistor connected state, the connection method of the equivalent circuit for the ignition resistor connected state is as follows:

[0021] Pin 1 of the MCU microcontroller U1 is connected to one end of the voltage divider resistor R1. Pin 2 of the MCU microcontroller U1 is connected to the input terminal of the integrated operational amplifier U3. The output terminal of the integrated operational amplifier U3 is connected to one end of the voltage divider resistor R1. Pin 3 of the MCU microcontroller U1 is connected to the input terminal of the integrated operational amplifier U4. The output terminal of the integrated operational amplifier U4 is connected to the other end of the voltage divider resistor R1. The other end of the voltage divider resistor R1 is connected to one end of the measuring circuit resistance Rd. The other end of the measuring circuit resistance Rd is connected to one end of the ignition resistor RX. The other end of the ignition resistor RX is connected to one end of the voltage divider resistor R2.

[0022] The third terminals of the integrated operational amplifiers U3 and U4 are respectively grounded, and the other terminal of the voltage divider resistor R2 is grounded.

[0023] Preferably, the circuit resistance Rd is calculated and measured based on the equivalent circuit of the bypass ignition resistor state:

[0024] ;

[0025] Where Vadc1 and Vadc2 are the measured values ​​of MCU_ADC1 and MCU_ADC2 respectively, which are based on the low voltage output of MCU microcontroller U1, and R1 and R2 are the resistance values ​​of voltage divider resistors R1 and R2 respectively.

[0026] Preferably, the value of the ignition resistance Rx is calculated based on the equivalent circuit of the access ignition resistance state:

[0027] ;

[0028] Among them, Vadc3 and Vadc4 are the measured values ​​of MCU_ADC3 and MCU_ADC4, respectively, based on the high voltage output of MCU microcontroller U1.

[0029] Preferably, the MCU microcontroller U1 reads the voltage value of the ADC twice after outputting a low voltage, and the MCU microcontroller U1 reads the voltage value of the ADC twice after outputting a high voltage.

[0030] Compared with the prior art, the beneficial effects of this application are as follows:

[0031] 1) By introducing a physical relay and performing two measurement processes under different conditions, the influence of the line resistance on the measurement path on the measurement results is effectively offset, which greatly improves the measurement accuracy;

[0032] 2) The introduction of a dual-channel integrated operational amplifier ensures that the ADC voltage value read by the MCU is accurate enough, thereby guaranteeing measurement accuracy;

[0033] 3) Two current-limiting voltage divider resistors are introduced to ensure that the measurement current through the ignition resistor is much smaller than the standard value, thus guaranteeing the safety of the measurement.

[0034] 4) The ignition resistance value can be calculated by reading the ADC voltage value only four times, making the measurement software implementation simpler. Attached Figure Description

[0035] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0036] Figure 1 This is a detection circuit diagram of a method for measuring the ignition resistance of an industrial electronic detonator according to an embodiment of the present invention;

[0037] Figure 2 This is an equivalent circuit diagram of the bypass ignition resistor state in an embodiment of the present invention;

[0038] Figure 3 This is an equivalent circuit diagram of the ignition resistor state in an embodiment of the present invention. Detailed Implementation

[0039] The preferred embodiments of the present invention will now be described with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0040] This invention provides a method for measuring the ignition resistance of an industrial electronic detonator, comprising:

[0041] The measurement of the ignition resistance of an industrial electronic detonator is based on a detection circuit, which includes: an MCU microcontroller U1, a single-pole double-throw physical relay U2, a relay switching transistor Q1, voltage divider resistors R1 and R2 of the measurement circuit, and a dual-channel integrated operational amplifier.

[0042] Test status based on the switching of ignition resistor by single-pole double-throw physical relay U2 and relay switching transistor Q1;

[0043] Based on the MCU microcontroller U1, a weak signal at the millivolt level is output to the measurement circuit to control the specific voltage values ​​of points A and B corresponding to voltage divider resistors R1 and R2 under different test conditions.

[0044] The specific voltage values ​​at points A and B are amplified by the same factor using a dual-channel integrated operational amplifier, thereby calculating the current value flowing through the measurement circuit and the ignition resistance value.

[0045] Preferably, the dual-channel integrated operational amplifier includes: integrated operational amplifier U3 and integrated operational amplifier U4;

[0046] like Figure 1 As shown, the specific connection method of the detection circuit is as follows: pin 1 of the MCU microcontroller U1 is connected to one end of the voltage divider resistor R1; pin 2 of the MCU microcontroller U1 is connected to the input terminal of the integrated operational amplifier U3; the output terminal of the integrated operational amplifier U3 is connected to one end of the voltage divider resistor R1; pin 3 of the MCU microcontroller U1 is connected to the input terminal of the integrated operational amplifier U4; the output terminal of the integrated operational amplifier U4 is connected to the other end of the voltage divider resistor R1.

[0047] Pin 4 of the MCU microcontroller U1 is connected to the base of the relay switching transistor Q1, and the collector of the relay switching transistor Q1 is connected to pin 8 of the single-pole double-throw physical relay U2.

[0048] Pin 1 of the single-pole double-throw physical relay U2 is connected to the power supply VCC; pin 3 of the single-pole double-throw physical relay U2 is connected to the other end of the voltage divider resistor R1; pin 6 of the single-pole double-throw physical relay U2 is connected to one end of the voltage divider resistor R2; pin 4 of the single-pole double-throw physical relay U2 is connected to the VB terminal of the ignition resistor RX; pin 5 of the single-pole double-throw physical relay U2 is connected to the VX terminal of the ignition resistor RX; pins 2 and 7 of the single-pole double-throw physical relay U2 are short-circuited.

[0049] The third terminals of the integrated operational amplifiers U3 and U4 are respectively grounded, and the emitter of the relay switching transistor Q1 and the other end of the voltage divider resistor R2 are respectively grounded.

[0050] Preferably, the test status of the ignition resistor includes: bypass ignition resistor status and connected ignition resistor status.

[0051] Preferably, when the test state is the bypass ignition resistor state, the connection method of the corresponding equivalent circuit for the bypass ignition resistor state is as follows:

[0052] like Figure 2 As shown, pin 1 of the MCU microcontroller U1 is connected to one end of the voltage divider resistor R1, pin 2 of the MCU microcontroller U1 is connected to the input terminal of the integrated operational amplifier U3, the output terminal of the integrated operational amplifier U3 is connected to one end of the voltage divider resistor R1, pin 3 of the MCU microcontroller U1 is connected to the input terminal of the integrated operational amplifier U4, the output terminal of the integrated operational amplifier U4 is connected to the other end of the voltage divider resistor R1, the other end of the voltage divider resistor R1 is connected to one end of the measuring circuit resistance Rd, and the other end of the measuring circuit resistance Rd is connected to one end of the voltage divider resistor R2.

[0053] The third terminals of the integrated operational amplifiers U3 and U4 are respectively grounded, and the other terminal of the voltage divider resistor R2 is grounded.

[0054] Preferably, when the test state is the ignition resistor connected state, the connection method of the equivalent circuit for the ignition resistor connected state is as follows:

[0055] In this embodiment, the ignition resistor of the target industrial electronic detonator refers to the key resistive element in the industrial electronic detonator used to generate an electric spark to ignite the charge head. Its resistance value is usually small and directly affects the detonator's initiation reliability and safety, ensuring that the detonator can ignite normally during blasting operations. For example, in tunnel blasting projects, the accuracy of the ignition resistor value determines whether a misfire or detonation accident will occur.

[0056] like Figure 3 As shown, pin 1 of the MCU microcontroller U1 is connected to one end of the voltage divider resistor R1; pin 2 of the MCU microcontroller U1 is connected to the input terminal of the integrated operational amplifier U3; the output terminal of the integrated operational amplifier U3 is connected to one end of the voltage divider resistor R1; pin 3 of the MCU microcontroller U1 is connected to the input terminal of the integrated operational amplifier U4; the output terminal of the integrated operational amplifier U4 is connected to the other end of the voltage divider resistor R1; the other end of the voltage divider resistor R1 is connected to one end of the measuring circuit resistance Rd; the other end of the measuring circuit resistance Rd is connected to one end of the ignition resistor RX; the other end of the ignition resistor RX is connected to one end of the voltage divider resistor R2; the third terminals of the integrated operational amplifier U3 and the integrated operational amplifier U4 are respectively grounded; and the other end of the voltage divider resistor R2 is grounded.

[0057] Preferably, the circuit resistance Rd is calculated and measured based on the equivalent circuit of the bypass ignition resistor state:

[0058] ;

[0059] Where Vadc1 and Vadc2 are the measured values ​​of MCU_ADC1 and MCU_ADC2 respectively, which are based on the low voltage output of MCU microcontroller U1, and R1 and R2 are the resistance values ​​of voltage divider resistors R1 and R2 respectively.

[0060] Preferably, the value of the ignition resistance Rx is calculated based on the equivalent circuit of the access ignition resistance state:

[0061] ;

[0062] Among them, Vadc3 and Vadc4 are the measured values ​​of MCU_ADC3 and MCU_ADC4, respectively, based on the high voltage output of MCU microcontroller U1.

[0063] Preferably, the MCU microcontroller U1 reads the voltage value of the ADC twice after outputting a low voltage, and the MCU microcontroller U1 reads the voltage value of the ADC twice after outputting a high voltage.

[0064] In this embodiment, the MCU microcontroller U1 can be a general-purpose MCU or any main control chip. Its main functions are: first, to output a controllable millivolt-level measurement voltage signal (MCU_DAC) to the measurement circuit, and can also control other voltage divider circuits to output a small measurement voltage; second, to output high and low levels (MCU_GPIO) to control the relay switching switch, so that the relay switches between different measurement states; third, to receive the measurement signals (MCU_ADC1, MCU_ADC2) output by the integrated operational amplifier; and fourth, to calculate the specific value of the ignition resistor using the measurement data.

[0065] The single-pole double-throw physical relay U2 and the relay switching transistor Q1 primarily function to switch between two different test states: "bypass ignition resistor" and "connected ignition resistor". Pin 1 of the relay is connected to VCC power, pin 8 is connected to the collector of the switching transistor, pins 2 and 7 are short-circuited, pins 3 and 6 are connected to the measurement path, and pins 4 and 5 are connected to the ignition resistor Rx of the electronic detonator. When the MCU outputs a low level, transistor Q1 is cut off, pins 3 and 2 of the relay are connected, and pins 6 and 7 are connected. The measurement circuit is shorted together through pins 3, 2, 7, and 6 of the relay, placing it in the "bypass ignition resistor state". When the MCU outputs a high level, transistor Q1 is turned on, pins 3 and 4 of the relay are connected, and pins 6 and 5 are connected, connecting the ignition resistor Rx to the measurement circuit, placing it in the "connected ignition resistor state".

[0066] The voltage divider resistors (R1, R2) in the measurement circuit: their main functions are, firstly, to provide a voltage divider for the entire measurement circuit, thus measuring the voltage. Figure 1 The specific voltage values ​​at points A and B are shown, and then the current flowing through the measuring circuit is calculated, finally determining the ignition resistor value. Secondly, current limiting is applied to the entire measuring circuit to ensure that the measured current through the ignition resistor does not exceed the standard 3mA.

[0067] Integrated operational amplifiers (U3, U4): Their main function is to amplify the voltage values ​​at points A and B by the same factor, so that the voltage values ​​(MCU_ADC1, MCU_ADC2) obtained by the MCU are more accurate.

[0068] Figure 2 In the diagram, "I1" represents the current in the measurement path, "Vadc1" and "Vadc2" are the voltage readings of the MCU, "Ua" is the voltage at point A, "Ub" is the voltage at point B, and "Rd" is the resistance of the measurement path. "R1" and "R2" are known precision resistance values.

[0069] The purpose of this measurement is to obtain the circuit resistance "Rd", and the steps to obtain it are as follows:

[0070] Step 1: The MCU outputs a low level, and the relay is in the "bypass ignition resistor test state";

[0071] Step 2: The MCU reads the measured values ​​of MCU_ADC1 and MCU_ADC2. Assuming the integrated operational amplifier has an amplification factor of β, then: Ua = Vadc1 / β, Ub = Vadc2 / β; --- Equation ①

[0072] Step 3: Calculate the current "I1" in the measurement path. According to Ohm's law: I1=(Ua-Ub) / R1=(Vadc1-Vadc2) / R1*β; ----- Equation ②

[0073] Step 4: Calculate the resistance value "Rd + R2". According to Ohm's law: Rd + R2 = Ub / I1, substitute into equations ① and ② and simplify to obtain the formula for calculating Rd:

[0074] ;

[0075] Figure 3 In the diagram, "I2" represents the current in the measurement path, "Vadc3" and "Vadc4" represent the voltage readings of the MCU, "Ua" represents the voltage at point A, "Ub" represents the voltage at point B, and "Rd" represents the resistance in the measurement path. "R1" and "R2" represent known precision resistance values, and "Rx" represents the ignition resistance value to be measured.

[0076] The purpose of this measurement is to obtain the ignition resistance value "Rx", and the steps to obtain it are as follows:

[0077] Step 1: The MCU outputs a high level to switch the relay to "connected ignition resistor test state";

[0078] Step 2: The MCU reads the measured values ​​of MCU_ADC3 and MCU_ADC4. Assuming the integrated operational amplifier has an amplification factor of β, then: Ua = Vadc3 / β, Ub = Vadc4 / β; --- Equation ①

[0079] Step 3: Calculate the current "I2" in the measuring path, according to Ohm's law:

[0080] I2=(Ua-Ub) / R1=(Vadc3-Vadc4) / R1*β;-----Equation ②

[0081] Step 4: Calculate the resistance value "Rd + Rx + R2". According to Ohm's law: Rd + Rx + R2 = Ub / I2, substitute into equations ① and ② and rearrange to obtain the formula for calculating Rx:

[0082]

[0083] Step 5: Combining Formula 1 and Formula 2, the final formula for calculating the ignition resistance value can be obtained: (R1 is a known resistance):

[0084] .

[0085] The beneficial effects of the above technical solution are: 1) By introducing a physical relay, the influence of the line resistance on the measurement result is effectively offset by two measurement processes under different states, which greatly improves the measurement accuracy;

[0086] 2) The introduction of a dual-channel integrated operational amplifier ensures that the ADC voltage value read by the MCU is accurate enough, thereby guaranteeing measurement accuracy;

[0087] 3) Two current-limiting voltage divider resistors are introduced to ensure that the measurement current through the ignition resistor is much smaller than the standard value, thus guaranteeing the safety of the measurement.

[0088] 4) The ignition resistance value can be calculated by reading the ADC voltage value only four times, making the measurement software implementation simpler.

[0089] By switching between "bypass ignition resistor" and "connected ignition resistor" states, the calculation of Rd (measured line resistance) and Rx (ignition resistor) is achieved using an MCU, relays, and operational amplifiers, thus resolving line resistance interference and measurement safety issues. However, this solution does not consider the impact of environmental factors (such as temperature, humidity, and air pressure) on resistance measurement—environmental fluctuations can cause the actual value of Rd to deviate, thereby affecting the calculation accuracy of Rx. Therefore, a dynamic environmental parameter correction mechanism is added. By collecting environmental data from sensors and combining it with historical trend analysis, Rd is corrected in real time, ultimately improving the measurement accuracy of Rx, forming a closed-loop solution of "hardware measurement + environmental correction," specifically including:

[0090] Based on multiple pre-installed sensors, various resistance measurement environmental parameters of the target industrial electronic detonator are collected to correct Rd, as follows:

[0091] Environmental parameters are collected by pre-installed sensors to obtain multiple initial resistance measurement environmental parameters of the target industrial electronic detonator.

[0092] Based on the historical resistance measurements of environmental parameters for each sensor, the changing trend of environmental parameters for each sensor is determined.

[0093] Based on the environmental parameter variation trend of each sensor, the corresponding initial resistance measurement environmental parameter of each sensor, and the acquisition time of each environmental parameter, the degree of matching between the initial resistance measurement environmental parameter and the corresponding environmental parameter variation trend is determined.

[0094] If the matching degree exceeds the preset value, the initial resistance measurement environment parameters will be determined as the resistance measurement environment parameters.

[0095] If the matching degree does not exceed the preset value, the virtual environmental parameters of the corresponding sensor are determined based on the trend of environmental parameter changes, and the resistance measurement environmental parameters of the corresponding sensor are determined based on the virtual environmental parameters and the initial resistance measurement environmental parameters.

[0096] The weight of each resistance measurement environment parameter is determined based on its influence on the measurement of the ignition resistance of the target industrial electronic detonator.

[0097] A measurement correction matrix is ​​constructed based on the weight of each resistance measurement environment parameter and the measurement environment parameter itself.

[0098] The adjustment matrix is ​​determined based on the circuit characteristics of the detection circuit. Simultaneously, the measurement feature vector of Rd is extracted through circuit detection. ;

[0099] Rd is corrected based on the adjustment matrix and the measurement correction matrix to obtain the corrected value;

[0100]

[0101] in, This is a correction value. For feature scaling factor, To adjust the matrix, Correction matrix for measured values, As an environmental inhibitor, It is a smoothing constant. The Frobenius norm is used to correct the matrix of measurements.

[0102] In this embodiment, multiple sensors are deployed in an environmental monitoring device near the industrial electronic detonator measurement area, covering key factors affecting resistance such as temperature, humidity, and air pressure (resistance increases with temperature, humidity may cause surface leakage, and air pressure affects the dielectric constant of air). The initial resistance measurement environmental parameters are the current environmental data collected by the sensors in real time, which are the "raw input" for correction. For example, the sensor selection is as follows: temperature is achieved using a PT100 RTD (accuracy ±0.1℃, converted to a digital signal via ADC), humidity is achieved using an SHT35 digital sensor (accuracy ±2%RH, I2C communication), and air pressure is achieved using a BMP388 (accuracy ±0.1kPa, sampling frequency 1Hz). Specifically, three sensors are evenly arranged around the detonator test bench with a spacing of ≤50cm to avoid local environmental deviations.

[0103] Data acquisition involves the MCU (such as STM32F4) reading sensor data every 5 seconds and recording it as initial parameters such as [T=25.3℃, H=58%RH, P=101.2kPa].

[0104] Historical resistance measurement environmental parameters are historical data accumulated by a single sensor over a long period of time (such as temperature records at 09:00 every day for the past year). They are used to explore the patterns of environmental changes. The trends of environmental parameter changes are divided into three categories: periodic trends (such as temperature "daily cycle: highest at 14:00, lowest at 6:00"): Fourier transform is used to extract the period, or moving average (window = period length, such as 24 hours) is used for fitting.

[0105] Linear trends (e.g., temperature increases by 0.5℃ per year): use linear regression (y=k*t+b, where t is time and k is the slope).

[0106] Nonlinear trends (such as humidity fluctuating with the seasons): Fit using LSTM neural networks or ARIMA models.

[0107] In this embodiment, the matching degree is based on |initial value - trend prediction value| / trend prediction value, which measures the degree of fit between real-time data and historical patterns (the greater the deviation, the higher the probability of sensor abnormality). The preset value is the maximum allowable deviation (e.g., 5%, determined by experimental testing within a reasonable range of environmental fluctuations).

[0108] Trend prediction predicts the temperature at the current moment (e.g., 14:30 on 2025 / 07 / 22) to be 25.0℃. For example, if the initial value is 25.8℃, the matching degree is |25.8-25.0| / 25.0=3.2%<5% (not exceeding the preset value, further processing is required).

[0109] The preset value calibration is the maximum matching degree when the measured Rx error is ≤3% in the constant temperature chamber, simulating environmental fluctuations. It is set to 5%.

[0110] Virtual environment parameters are the "theoretical values" (environmental values ​​without sensor error) predicted by the trend model.

[0111] The resistance measurement environment parameters are the final effective parameters used for correction (the fusion of initial or dummy values).

[0112] For example: virtual parameter generation: the trend model predicts the temperature to be 25.0℃ (virtual value).

[0113] Threshold judgment: Set the temperature threshold to 1℃ (through experiments, when the temperature deviation is >1℃, the Rx error exceeds 5%).

[0114] Fusion logic: Initial 25.8℃ vs virtual 25.0℃, difference 0.8℃ < 1℃ → take the average 25.4℃.

[0115] If the initial temperature is 23.0℃ (difference of 2.0℃ > 1℃), then directly use the virtual value of 25.0℃.

[0116] Threshold calibration: Test the rate of change of Rx with temperature in a high and low temperature chamber (e.g., Rx changes by 0.5Ω for every 1℃ change in temperature) and then calculate the allowable temperature deviation.

[0117] The degree of influence of measurement is the extent to which environmental parameters affect the measurement of Rx (quantified experimentally, such as the effect of temperature on resistance being much greater than that of humidity).

[0118] The weights are adjusted priorities assigned based on the degree of influence (the greater the influence, the higher the weight).

[0119] Temperature effect: In a constant temperature chamber, with fixed humidity and air pressure, the change of Rx with temperature is measured (e.g., when T changes from 20 to 30℃, Rx changes from 10 to 10.5Ω, with a change rate of 0.05Ω / ℃).

[0120] Humidity effect: In a humidity chamber, with fixed temperature and air pressure, measure the change of Rx with humidity (e.g., when H changes from 50 to 60%RH, Rx changes from 10 to 10.1Ω, with a change rate of 0.01Ω / %RH).

[0121] Weighting calculation: Total influence 0.05 + 0.01 + 0.001 = 0.061 (the influence of air pressure is negligible, set to 0.001), so the weights are: temperature 0.82 (0.05 / 0.061), humidity 0.16 (0.01 / 0.061), and air pressure 0.02 (normalized).

[0122] In this embodiment, the measurement correction matrix is ​​a matrix constructed from the weights and values ​​of environmental parameters, used to systematically correct the measurement values. for:

[0123] ;

[0124] in, For environmental parameter weight vectors, This is the adjusted vector of resistance measurement environment parameters. It is an n-dimensional identity matrix. This is the environmental coupling gain coefficient.

[0125] In this embodiment, the adjustment matrix is ​​obtained based on the characteristics of the measurement system, such as the signal amplification factor.

[0126] In this embodiment, The physical meaning is to quantify the intensity of the influence of environmental parameters on Rd, and the coupling effect between parameters (such as temperature and humidity interaction). The physical meaning is the distortion of the measurement signal caused by the non-ideal characteristics of the quantization circuit (such as gain drift leading to voltage amplification error).

[0127] Circuit characteristics are the hardware features of the detection circuit (such as operational amplifier gain and relay switching time, which affect signal acquisition accuracy), while the adjustment matrix quantifies the impact of circuit characteristics on measurement (e.g., if the gain is 100, the matrix contains 100 elements).

[0128] The measurement feature vector is the signal characteristic during Rd measurement (such as voltage fluctuation standard deviation, current stability, reflecting measurement quality). Circuit feature measurement: operational amplifier U2 gain G=100 (multimeter measures input-output voltage ratio), relay K1 switching time t=10ms (oscilloscope measures level jump).

[0129] Adjust matrix A=diag([100,1 / 10,...]) (gain amplifies the signal; switching time affects measurement timing).

[0130] Feature vector extraction: Collect voltage values ​​of Rd 100 times and calculate the standard deviation. (Reflecting fluctuations), current stability = ±0.05mA, forming a vector. .

[0131] The feature scaling factor limits the correction magnitude (e.g., setting it to 0.1 to avoid overcorrection in extreme environments).

[0132] The environmental inhibition factor weakens strong environmental disturbances and is generally 0.05.

[0133] The smoothing constant is used to prevent the denominator from being zero (e.g., ...). (to ensure operational stability).

[0134] In this embodiment, The function limits the correction range through saturation characteristics to avoid overcorrection under extreme conditions (such as high temperature causing the theoretical correction value to far exceed the actual value, tanh will compress its influence). The exp function reflects the global attenuation of environmental disturbances - when the norm of the environmental correction matrix is ​​large (the disturbance is strong), the exp term approaches 0, and the correction is mainly dominated by the local nonlinearity of tanh; when the disturbance is weak, the exp term approaches 1, and the two work together to correct.

[0135] That is: if environmental interference is strong ( (For large terms), the exp term approaches 0, and the correction is mainly dominated by the tanh term;

[0136] If environmental interference is weak ( (small), the exp term approaches 1, and the two are corrected together.

[0137] The beneficial effects of the above scheme are as follows: By using historical data from each sensor, the changing trend of environmental parameters is determined. Combined with this trend, it is determined whether the initial resistance measurement environmental parameters conform to the changing trend. If they do, the initial resistance measurement environmental parameters are used as the resistance measurement environmental parameters. If they do not conform, a virtual value is determined based on the changing trend. The two are then combined to obtain the resistance measurement environmental parameters, thus avoiding the impact of sensor problems on these parameters. By assessing the influence of the resistance measurement environmental parameters on the ignition resistance of the target industrial electronic detonator, the weight of each resistance measurement environmental parameter is determined. Combining the weights and parameters of each parameter, a measurement correction matrix is ​​constructed. Based on measurement characteristics, an adjustment matrix is ​​determined to correct Rd. This improves the measurement reliability of the industrial electronic detonator ignition resistance from two dimensions: "hardware measurement accuracy assurance" and "software environmental interference elimination," meeting the stringent requirements for resistance accuracy (error ≤ 5%) in blasting operations.

[0138] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method for measuring the ignition resistance of an industrial electronic detonator, characterized in that, include: The measurement of the ignition resistance of an industrial electronic detonator is based on a detection circuit, which includes: an MCU microcontroller U1, a single-pole double-throw physical relay U2, a relay switching transistor Q1, voltage divider resistors R1 and R2 of the measurement circuit, and a dual-channel integrated operational amplifier. Test status based on the switching of ignition resistor by single-pole double-throw physical relay U2 and relay switching transistor Q1; Based on the MCU microcontroller U1, a weak signal at the millivolt level is output to the measurement circuit to control the measurement of the specific voltage values ​​at points A and B under different test conditions based on voltage divider resistors R1 and R2. The specific voltage values ​​at points A and B are amplified by the same factor using a dual-channel integrated operational amplifier, thereby calculating the current value flowing through the measurement circuit and the ignition resistance value. The dual-channel integrated operational amplifier includes: integrated operational amplifier U3 and integrated operational amplifier U4; The specific connection method of the detection circuit is as follows: pin 1 of the MCU microcontroller U1 is connected to one end of the voltage divider resistor R1; pin 2 of the MCU microcontroller U1 is connected to the input terminal of the integrated operational amplifier U3; the output terminal of the integrated operational amplifier U3 is connected to one end of the voltage divider resistor R1; pin 3 of the MCU microcontroller U1 is connected to the input terminal of the integrated operational amplifier U4; and the output terminal of the integrated operational amplifier U4 is connected to the other end of the voltage divider resistor R1. Pin 4 of the MCU microcontroller U1 is connected to the base of the relay switching transistor Q1, and the collector of the relay switching transistor Q1 is connected to pin 8 of the single-pole double-throw physical relay U2. Pin 1 of the single-pole double-throw physical relay U2 is connected to the power supply VCC; pin 3 of the single-pole double-throw physical relay U2 is connected to the other end of the voltage divider resistor R1; pin 6 of the single-pole double-throw physical relay U2 is connected to one end of the voltage divider resistor R2; pin 4 of the single-pole double-throw physical relay U2 is connected to the VB terminal of the ignition resistor RX; pin 5 of the single-pole double-throw physical relay U2 is connected to the VX terminal of the ignition resistor RX; pins 2 and 7 of the single-pole double-throw physical relay U2 are short-circuited. The third terminals of the integrated operational amplifiers U3 and U4 are respectively grounded, and the emitter of the relay switching transistor Q1 and the other end of the voltage divider resistor R2 are respectively grounded. When the MCU microcontroller U1 outputs a low level, the relay switching transistor Q1 is cut off, and pins 3 and 2 of the single-pole double-throw physical relay U2 are connected, and pins 6 and 7 are connected. The measurement circuit is shorted together through pins 3, 2, 7, and 6 of the relay. When the MCU microcontroller U1 outputs a high level, the relay switching transistor Q1 is turned on, and pins 3 and 4 of the single-pole double-throw physical relay U2 are connected, and pins 6 and 5 are connected, connecting the ignition resistor Rx to the measurement circuit. Point A is one end of the voltage divider resistor R1, and point B is the other end of the voltage divider resistor R1.

2. The method for measuring the ignition resistance of an industrial electronic detonator according to claim 1, characterized in that, The test status of the ignition resistor includes: bypass ignition resistor status and connected ignition resistor status.

3. The method for measuring the ignition resistance of an industrial electronic detonator according to claim 2, characterized in that, When the test state is the bypass ignition resistor state, the connection method of the corresponding equivalent circuit for the bypass ignition resistor state is as follows: Pin 1 of the MCU microcontroller U1 is connected to one end of the voltage divider resistor R1. Pin 2 of the MCU microcontroller U1 is connected to the input terminal of the integrated operational amplifier U3. The output terminal of the integrated operational amplifier U3 is connected to one end of the voltage divider resistor R1. Pin 3 of the MCU microcontroller U1 is connected to the input terminal of the integrated operational amplifier U4. The output terminal of the integrated operational amplifier U4 is connected to the other end of the voltage divider resistor R1. The other end of the voltage divider resistor R1 is connected to one end of the measuring circuit resistance Rd. The other end of the measuring circuit resistance Rd is connected to one end of the voltage divider resistor R2. The third terminals of the integrated operational amplifiers U3 and U4 are respectively grounded, and the other terminal of the voltage divider resistor R2 is grounded.

4. The method for measuring the ignition resistance of an industrial electronic detonator according to claim 2, characterized in that, When the test state is the ignition resistor connected state, the connection method of the equivalent circuit for the ignition resistor connected state is as follows: Pin 1 of the MCU microcontroller U1 is connected to one end of the voltage divider resistor R1. Pin 2 of the MCU microcontroller U1 is connected to the input terminal of the integrated operational amplifier U3. The output terminal of the integrated operational amplifier U3 is connected to one end of the voltage divider resistor R1. Pin 3 of the MCU microcontroller U1 is connected to the input terminal of the integrated operational amplifier U4. The output terminal of the integrated operational amplifier U4 is connected to the other end of the voltage divider resistor R1. The other end of the voltage divider resistor R1 is connected to one end of the measuring circuit resistance Rd. The other end of the measuring circuit resistance Rd is connected to one end of the ignition resistor RX. The other end of the ignition resistor RX is connected to one end of the voltage divider resistor R2. The third terminals of the integrated operational amplifiers U3 and U4 are respectively grounded, and the other terminal of the voltage divider resistor R2 is grounded.

5. The method for measuring the ignition resistance of an industrial electronic detonator according to claim 3, characterized in that, The circuit resistance Rd is calculated and measured based on the equivalent circuit of the bypass ignition resistor state. ； Where Vadc1 and Vadc2 are the measured values ​​of pin 2 and pin 3 of MCU microcontroller U1, respectively, when MCU microcontroller U1 outputs a low voltage; and R1 and R2 are the resistance values ​​of voltage divider resistors R1 and R2, respectively.

6. The method for measuring the ignition resistance of an industrial electronic detonator according to claim 5, characterized in that, Calculate the value of the ignition resistance Rx based on the equivalent circuit of the access ignition resistance state: ； Among them, Vadc3 and Vadc4 are the measured values ​​of pin 2 and pin 3 of MCU microcontroller U1, respectively, based on the output high voltage of MCU microcontroller U1.

7. The method for measuring the ignition resistance of an industrial electronic detonator according to claim 6, characterized in that, When the MCU microcontroller U1 outputs a low voltage, the voltage values ​​of pin 2 and pin 3 of the MCU microcontroller U1 are read. When the MCU microcontroller U1 outputs a high voltage, the voltage values ​​of pin 2 and pin 3 of the MCU microcontroller U1 are read.

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