A pyrotechnic device detection apparatus

Abstract

The utility model provides a kind of pyrotechnics detection equipment, including shell, the shell side respectively installs test interface and host computer interface, battery module is installed in the shell interior, the baffle is installed in battery module one side, and the battery module other side installs plastic protective shell, pyrotechnics test circuit board is installed in the plastic protective shell interior, and plastic protective cover is installed in the plastic protective shell top.The utility model has the beneficial effect: through the design of four-wire system cable, eliminate the influence of cable impedance on test result, improve pyrotechnics test precision, through the current voltage protection circuit of constant-current source output, output isolation circuit, the selection of lithium sulfonyl chloride power supply battery, realize the nature safety of pyrotechnics measurement, prolong the continuous use time of test equipment, with long storage time, many times of continuous use etc.

Description

Technical Field

[0001] This utility model belongs to the field of pyrotechnic testing technology, and in particular relates to a pyrotechnic testing device. Background Technology

[0002] Pyrotechnics are essential components in the aerospace industry, primarily used for pneumatic manipulation of engine ignition, booster separation, and control surface deployment. Achieving planned control objectives requires a series of pyrotechnic actions. Ensuring the quality of pyrotechnics is crucial for their effective use. Automated detection of pyrotechnic circuits guarantees quality and safe operation, significantly reducing risks and minimizing manpower costs. When measuring assembled pyrotechnics, operators must maintain a considerable distance (generally over 10 meters) for safety, measuring at a precision of 0.15 mm. 2 Taking conductors with different cross-sectional areas as an example, the resistance value of a two-wire system is about 2Ω higher than that of a four-wire system. This resistance value is higher than that of a considerable number of pyrotechnic devices, which means that the cable impedance has a significant impact on the measurement results of pyrotechnic devices. At the same time, ensuring the inherent safety of the pyrotechnic device measurement process after assembly is an important requirement for testing instruments. Furthermore, the products containing pyrotechnic devices (such as missiles and detonators) have long storage periods, generally 5 to 10 years, which places high demands on the battery storage characteristics of the supporting pyrotechnic device monitoring equipment.

[0003] Currently, the most common methods for testing pyrotechnics include using detonator testers, pyrotechnic testing devices, and pyrotechnic self-testing circuits. Existing technologies typically employ two-wire measurements, amplifying the acquired signal before outputting it. This method cannot eliminate the influence of cable impedance on the test results, significantly reducing the accuracy of pyrotechnic testing. Furthermore, existing technologies cannot guarantee inherent safety during the testing process, and they often rely on dry cell batteries, resulting in short operating times and a maximum current of 15 amps, far exceeding the safe current of pyrotechnics (100mA), thus failing to guarantee inherent safety during testing. Utility Model Content

[0004] In view of this, the present invention aims to propose a pyrotechnics testing device to solve the problems of low testing accuracy, low safety and short working time of the existing technology.

[0005] To achieve the above objectives, the technical solution created by this utility model is implemented as follows: In a first aspect, this utility model provides a pyrotechnic testing device. The pyrotechnic testing device includes a housing, a test interface and a host computer interface are respectively installed on the side of the housing, a battery module is installed inside the housing, a partition is installed on one side of the battery module, and a plastic protective shell is installed on the other side of the battery module. A pyrotechnic testing circuit board is installed inside the plastic protective shell, and a plastic protective cover is installed on the top of the plastic protective shell. The battery module provides power to the pyrotechnic test circuit board, which is electrically connected to the host computer interface. The pyrotechnic test circuit board is connected to the test interface via a four-wire cable, and the test interface is connected to the pyrotechnic. The battery module includes a battery, a non-locking switch, and a voltage regulator circuit. The battery is connected to the non-locking switch, the non-locking switch is connected to the voltage regulator circuit, and the non-locking switch is mounted on the side of the housing. The pyrotechnics test circuit board includes a constant current source circuit, an output current and voltage protection circuit, a voltage acquisition and amplification circuit, an AD conversion circuit, an MCU, and a signal isolation output circuit. The constant current source circuit is connected to the output current and voltage protection circuit, the output current and voltage protection circuit is connected to the pyrotechnic device, the pyrotechnic device is connected to the voltage acquisition and amplification circuit, the voltage acquisition and amplification circuit is connected to the AD conversion circuit, the AD conversion circuit is connected to the MCU, the MCU is connected to the signal isolation output circuit, the signal isolation output circuit is connected to the host computer interface, and the host computer interface is connected to the host computer.

[0006] Furthermore, the four-wire cable includes cable L1, cable L2, cable L3, and cable L4. One end of cable L1 is connected to the positive terminal of a constant current source, and the other end of cable L1 is connected to the positive terminal of a pyrotechnic device. One end of cable L2 is connected to the negative terminal of a constant current source, and the other end of cable L2 is connected to the negative terminal of a pyrotechnic device. One end of cable L3 is connected to the positive input terminal of a voltage amplifier, and the other end of cable L3 is connected to the positive terminal of a pyrotechnic device. One end of cable L4 is connected to the negative input terminal of a voltage amplifier, and the other end of cable L4 is connected to the negative terminal of a pyrotechnic device.

[0007] Furthermore, the output current and voltage protection circuit includes resistor R33, resistor R50 and Zener diode V1. One end of resistor R33 is connected to one end of resistor R50, the other end of resistor R33 is connected to the positive terminal of constant current source, and the other end of resistor R50 is connected to the output port of constant current source and Zener diode V1.

[0008] Furthermore, the signal isolation output circuit includes an optical isolation chip U9, a pull-up resistor R49, a light-emitting diode D5, and a pull-up resistor R56. The positive output terminal of the optical isolation chip U9 is connected to the output interface TXD terminal, and the negative output terminal of the optical isolation chip U9 is grounded. One end of the pull-up resistor R49 is connected to the power supply VCC, and the other end of the pull-up resistor R49 is connected to the positive input terminal of the optical isolation chip U9. The negative terminal of the light-emitting diode D5 is connected to the negative input terminal of the optical isolation chip U9, and the positive terminal of the light-emitting diode D5 is connected to one end of the pull-up resistor R56. The other end of the pull-up resistor R56 is connected to the power supply 3V3.

[0009] Furthermore, the constant current source circuit includes operational amplifier U2A, operational amplifier U2B, resistors R5, R6, R9, R10, and R29. One end of resistor R5 is connected to the reference voltage VREF1V25, and the other end of resistor R5 is connected to the non-inverting input terminal of operational amplifier U2A and one end of resistor R6. The other end of resistor R6 is connected to the output terminal and the inverting input terminal of operational amplifier U2B. One end of resistor R9 is connected to the inverting input terminal of operational amplifier U2A and one end of resistor R10, and the other end of resistor R9 is grounded. The other end of resistor R10 is connected to the output terminal of operational amplifier U2A and one end of resistor R29. The other end of resistor R29 is connected to the non-inverting input terminal of operational amplifier U2B.

[0010] Furthermore, the voltage acquisition and amplification circuit includes an operational amplifier U8A, resistors R41, R42, R47, R27, R61, capacitors C19 and C11. One end of resistor R41 is connected to the positive terminal of the pyrotechnic device, and the other end of resistor R41 is connected to the non-inverting input terminal of operational amplifier U8A and one end of resistor R61. The other end of resistor R61 is grounded. One end of resistor R47 is connected to the negative terminal of the pyrotechnic device, and the other end of resistor R47 is connected to the inverting input terminal of operational amplifier U8A and one end of resistor R27. The other end of resistor R27 is connected to the output terminal of operational amplifier U8A and one end of resistor R42. The other end of resistor R42 is connected to one end of capacitor C11, and the other end of capacitor C11 is grounded. One end of capacitor C19 is connected to the positive power supply of operational amplifier U8A, and the other end of capacitor C19 is grounded.

[0011] Furthermore, the AD conversion circuit includes an AD conversion chip, resistors R22, R8, R11, R3, R7, and capacitor C9. One end of resistor R22 is connected to a 3V3 power supply, and the other end of resistor R22 is connected to the RDY pin of the AD conversion chip. One end of resistor R8 is connected to one end of resistor R3, and the other end of resistor R8 is connected to the SCL pin of the AD conversion chip. The other end of resistor R3 is connected to a 3V3 power supply. One end of resistor R11 is connected to one end of resistor R7, and the other end of resistor R11 is connected to the SDA pin of the AD conversion chip. The other end of resistor R7 is connected to a 3V3 power supply. One end of capacitor C9 is connected to the VDD pin of the AD conversion chip, and the other end of capacitor C9 is grounded.

[0012] Furthermore, the battery is a lithium thionyl chloride battery. In the event of an accident, such as a circuit mis-short circuit or damage to the test equipment caused by violent destruction, resulting in the positive and negative terminals of the battery being directly connected to the pyrotechnic device, the current of the pyrotechnic device will be controlled within 100mA, which is lower than the safe current of the pyrotechnic device, thus ensuring the inherent safety of the measurement.

[0013] Compared with existing technologies, the pyrotechnics testing equipment described in this invention has the following advantages: (1) By designing a four-wire cable, the influence of cable impedance on the test results is eliminated, thus improving the accuracy of pyrotechnics testing; (2) By selecting the constant current source output current and voltage protection circuit, output isolation circuit, and lithium thionyl chloride power supply battery, the inherent safety of the measurement is achieved. The power supply battery capacity is about 10 times that of ordinary dry batteries, which extends the continuous use time or number of uses of the test equipment. (3) The ER14505 battery has a storage time of 10 years, which theoretically allows the pyrotechnics testing equipment to be maintenance-free for 10 years.

[0014] (4) In the event of an accident, such as a circuit being accidentally short-circuited or the test equipment being violently damaged, resulting in the battery's positive and negative terminals being directly connected to the pyrotechnic device, the pyrotechnic device's current will be controlled to within 100mA, which is lower than the pyrotechnic device's safe current, thus ensuring the inherent safety of the measurement. Attached Figure Description

[0015] The accompanying drawings, which form part of this utility model, are used to provide a further understanding of the utility model. The illustrative embodiments of the utility model and their descriptions are used to explain the utility model and do not constitute an undue limitation of the utility model. In the drawings: Figure 1 This is a schematic diagram of the mechanical structure described in an embodiment of the present utility model; Figure 2 This is a schematic diagram of the functional block diagram according to an embodiment of the present utility model; Figure 3 This is a schematic diagram of a four-wire cable according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the output current and voltage protection circuit described in an embodiment of the present invention; Figure 5 This is a schematic diagram of the signal isolation output circuit described in an embodiment of the present invention; Figure 6 This is a schematic diagram of the constant current source circuit described in an embodiment of the present invention; Figure 7 This is a schematic diagram of the voltage acquisition and amplification circuit described in an embodiment of the present invention; Figure 8 This is a schematic diagram of the AD conversion circuit described in an embodiment of the present invention.

[0016] Explanation of reference numerals in the attached figures: 1. Test interface; 2. Plastic protective shell; 3. Plastic protective cover; 4. Pyrotechnics test circuit board; 5. Battery; 6. Separator; 7. Host computer interface. Detailed Implementation

[0017] It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments of the present invention can be combined with each other.

[0018] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this utility model 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 this utility model. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0019] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" 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 this utility model based on the specific circumstances.

[0020] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0021] like Figures 1 to 8 As shown, a pyrotechnic testing device includes a housing. A test interface 1, a host computer interface 7, and a non-locking switch are respectively installed on the side of the housing. A battery module 5 is installed inside the housing. A partition 6 is installed on one side of the battery module 5, and a plastic protective shell 2 is installed on the other side. A pyrotechnic testing circuit board 4 is installed inside the plastic protective shell 2, and a plastic protective cover 3 is installed on the top of the plastic protective shell 2. The battery module 5 provides power to the pyrotechnic testing circuit board 4. The pyrotechnic testing circuit board 4 is electrically connected to the host computer interface 7. The pyrotechnic testing circuit board 4 is connected to the test interface 1 via a four-wire cable. The test interface 1 is connected to a pyrotechnic item. The battery module 5 includes a battery. 5. A non-locking switch and a voltage regulator circuit: The battery 5 is connected to the non-locking switch, and the non-locking switch is connected to the voltage regulator circuit; The pyrotechnic test circuit board 4 includes a constant current source circuit, an output current and voltage protection circuit, a voltage acquisition and amplification circuit, an AD conversion circuit, an MCU, and a signal isolation output circuit; The constant current source circuit is connected to the output current and voltage protection circuit, the output current and voltage protection circuit is connected to the pyrotechnic, the pyrotechnic is connected to the voltage acquisition and amplification circuit, the voltage acquisition and amplification circuit is connected to the AD conversion circuit, the AD conversion circuit is connected to the MCU, the MCU is connected to the signal isolation output circuit, the signal isolation output circuit is connected to the host computer interface 7, and the host computer interface 7 is connected to the host computer.

[0022] The specific implementation method is as follows: In a preferred embodiment of this invention, the four-wire cable includes cables L1, L2, L3, and L4. One end of cable L1 is connected to the positive terminal of a constant current source, and the other end of cable L1 is connected to the positive terminal of a pyrotechnic device. One end of cable L2 is connected to the negative terminal of a constant current source, and the other end of cable L2 is connected to the negative terminal of a pyrotechnic device. One end of cable L3 is connected to the positive input terminal of a voltage amplifier, and the other end of cable L3 is connected to the positive terminal of a pyrotechnic device. One end of cable L4 is connected to the negative input terminal of a voltage amplifier, and the other end of cable L4 is connected to the negative terminal of a pyrotechnic device. In this embodiment, cables L3 and L4 directly transmit the voltage at the connection point between the pyrotechnic device and cables L1 and L2 to the input terminal of the voltage amplifier circuit. This voltage does not include the voltage drop across cables L1 and L2, thereby eliminating the influence of cable impedance on the test results and greatly improving the testing accuracy of the pyrotechnic device.

[0023] In a preferred embodiment of this invention, the output current and voltage protection circuit includes resistors R33 and R50, and a Zener diode V1. One end of resistor R33 is connected to one end of resistor R50, and the other end of resistor R33 is connected to the positive terminal of the constant current source. The other end of resistor R50 is connected to the output port of the constant current source and the Zener diode V1. In this embodiment, in the event of an accident, the positive output terminal of the constant current source is directly connected to a 3.6V voltage. Resistors R33 and R50 can limit the current of the pyrotechnic device to within 55mA through their own resistance values. Even if one resistor is short-circuited, the current can still be limited to within 92mA, which is lower than the safe current of the pyrotechnic device. The Zener diode V1 is an MMBZ5V6 dual overvoltage diode. When the output voltage of the constant current source is abnormal and exceeds 5.6V, the Zener diode V1 will attract current through its own breakdown effect, thereby protecting the pyrotechnic device connected to the output interface of the constant current source.

[0024] In a preferred embodiment of this invention, the signal isolation output circuit includes an optical isolation chip U9, a pull-up resistor R49, a light-emitting diode D5, and a pull-up resistor R56. The positive output terminal of the optical isolation chip U9 is connected to the TXD terminal of the output interface, and the negative output terminal of the optical isolation chip U9 is grounded. One end of the pull-up resistor R49 is connected to the power supply VCC, and the other end of the pull-up resistor R49 is connected to the positive input terminal of the optical isolation chip U9. The negative terminal of the light-emitting diode D5 is connected to the negative input terminal of the optical isolation chip U9, and the positive terminal of the light-emitting diode D5 is connected to one end of the pull-up resistor R56. The other end of the pull-up resistor R56 is connected to the 3V3 power supply. In this embodiment, the optical isolation chip U9 transmits the UART signal to the external host computer through optical isolation, ensuring electrical isolation between the pyrotechnic device testing circuit and the external circuit, thereby preventing the pyrotechnic device from being affected by the host computer circuit.

[0025] In a preferred embodiment of this invention, the battery is a lithium thionyl chloride battery. The low current output characteristic of the lithium thionyl chloride battery (maximum output current not exceeding 100mA) also ensures intrinsic safety. In this embodiment, the battery's internal resistance is approximately 12.5V, which is much higher than that of ordinary dry cell batteries (60-120 milliohms). In the event of an accident (such as a circuit short circuit or damage to the test equipment caused by violent destruction, resulting in the battery's positive and negative terminals being directly connected to the pyrotechnic device), the pyrotechnic device current will be controlled below 100mA, which is lower than the safe current of the pyrotechnic device, ensuring the intrinsic safety of the measurement. Furthermore, the battery capacity is 2600mAh@3.6V, which is more than 10 times that of an ordinary dual-cell dry cell battery (280mAh@3V), increasing the service life of the test equipment. At the same time, the ER14505 battery has a storage life of 10 years, while the storage life of ordinary dry cell batteries is only 2 to 5 years, increasing the maintenance-free time of the pyrotechnic device test equipment by 2 to 5 times.

[0026] In a preferred embodiment of this utility model, the AD conversion circuit includes an AD conversion chip, resistors R22, R8, R11, R3, R7, and capacitor C9. One end of resistor R22 is connected to a 3V3 power supply, and the other end of resistor R22 is connected to the RDY pin of the AD conversion chip. One end of resistor R8 is connected to one end of resistor R3, and the other end of resistor R8 is connected to the SCL pin of the AD conversion chip. The other end of resistor R3 is connected to a 3V3 power supply. One end of resistor R11 is connected to one end of resistor R7, and the other end of resistor R11 is connected to the SDA pin of the AD conversion chip. The other end of resistor R7 is connected to a 3V3 power supply. One end of capacitor C9 is connected to the VDD pin of the AD conversion chip, and the other end of capacitor C9 is grounded. In this embodiment, the AD conversion circuit and MCU respectively adopt an ultra-small low-power AD acquisition chip (SGM58200) and an ultra-low power MCU chip (HC32L130J8TA), so that the total power consumption of the device does not exceed 0.5W when it is working. Theoretically, it can be used for more than 18 hours when the battery is fully charged. Based on a measurement time of 5 seconds, it can continuously measure more than 12,000 times.

[0027] In a preferred embodiment of this utility model, the constant current source circuit includes operational amplifier U2A, operational amplifier U2B, resistors R5, R6, R9, R10, and R29. One end of resistor R5 is connected to the reference voltage VREF1V25, and the other end of resistor R5 is connected to the non-inverting input terminal of operational amplifier U2A and one end of resistor R6. The other end of resistor R6 is connected to the output terminal and the inverting input terminal of operational amplifier U2B. One end of resistor R9 is connected to the inverting input terminal of operational amplifier U2A and one end of resistor R10, and the other end of resistor R9 is grounded. The other end of resistor R10 is connected to the output terminal of operational amplifier U2A and one end of resistor R29. The other end of resistor R29 is connected to the non-inverting input terminal of operational amplifier U2B. The voltage acquisition and amplification circuit includes an operational amplifier... The amplifier includes an operational amplifier U8A, resistors R41, R42, R47, R27, R61, capacitors C19 and C11. One end of resistor R41 is connected to the positive terminal of the pyrotechnic device, and the other end of resistor R41 is connected to the non-inverting input terminal of operational amplifier U8A and one end of resistor R61. The other end of resistor R61 is grounded. One end of resistor R47 is connected to the negative terminal of the pyrotechnic device, and the other end of resistor R47 is connected to the inverting input terminal of operational amplifier U8A and one end of resistor R27. The other end of resistor R27 is connected to the output terminal of operational amplifier U8A and one end of resistor R42. The other end of resistor R42 is connected to one end of capacitor C11, and the other end of capacitor C11 is grounded. One end of capacitor C19 is connected to the positive power supply of operational amplifier U8A, and the other end of capacitor C19 is grounded. In this embodiment, the constant current source circuit achieves stable current output through a negative feedback closed-loop system. The output current is sampled (sampling resistor) and compared with the reference voltage. The output is adjusted using an operational amplifier to offset the effects of load changes or input voltage fluctuations. The voltage acquisition and amplification circuit extracts the weak voltage signal (mV level) and converts it into a processable electrical signal. The high input impedance front end reduces the signal source load effect and ensures acquisition accuracy.

[0028] The beneficial effects of this utility model are as follows: (1) By designing a four-wire cable, the influence of cable impedance on the test results is eliminated, thus improving the accuracy of pyrotechnics testing; (2) By selecting the constant current source output current and voltage protection circuit, output isolation circuit, and lithium thionyl chloride power supply battery, the inherent safety of the measurement is achieved. The power supply battery capacity is about 10 times that of ordinary dry batteries, which extends the continuous use time or number of uses of the test equipment. (3) The ER14505 battery has a storage time of 10 years, which theoretically allows the pyrotechnics testing equipment to be maintenance-free for 10 years.

[0029] (4) In the event of an accident, such as a circuit being accidentally short-circuited or the test equipment being violently damaged, resulting in the battery's positive and negative terminals being directly connected to the pyrotechnic device, the pyrotechnic device's current will be controlled to within 100mA, which is lower than the pyrotechnic device's safe current, thus ensuring the inherent safety of the measurement.

[0030] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A pyrotechnics testing device, characterized in that: The device includes an outer shell, on the side of which a test interface (1) and a host computer interface (7) are respectively installed. A battery module is installed inside the outer shell. A partition (6) is installed on one side of the battery module, and a plastic protective shell (2) is installed on the other side of the battery module. A pyrotechnics test circuit board (4) is installed inside the plastic protective shell (2), and a plastic protective cover (3) is installed on the top of the plastic protective shell (2). The battery module provides power to the pyrotechnic test circuit board (4), which is electrically connected to the host computer interface (7). The pyrotechnic test circuit board (4) is connected to the test interface (1) via a four-wire cable, and the test interface (1) is connected to the pyrotechnic. The battery module includes a battery (5), a non-locking switch and a voltage regulator circuit. The battery (5) is connected to the non-locking switch, the non-locking switch is connected to the voltage regulator circuit, and the non-locking switch is installed on the side of the housing. The pyrotechnics test circuit board (4) includes a constant current source circuit, an output current and voltage protection circuit, a voltage acquisition and amplification circuit, an AD conversion circuit, an MCU, and a signal isolation output circuit; The constant current source circuit is connected to the output current and voltage protection circuit, the output current and voltage protection circuit is connected to the pyrotechnic device, the pyrotechnic device is connected to the voltage acquisition and amplification circuit, the voltage acquisition and amplification circuit is connected to the AD conversion circuit, the AD conversion circuit is connected to the MCU, the MCU is connected to the signal isolation output circuit, the signal isolation output circuit is connected to the host computer interface (7), and the host computer interface (7) is connected to the host computer. The constant current source circuit includes operational amplifier U2A, operational amplifier U2B, resistors R5, R6, R9, R10, and R29. One end of resistor R5 is connected to the reference voltage VREF1V25, and the other end of resistor R5 is connected to the non-inverting input of operational amplifier U2A and one end of resistor R6. The other end of resistor R6 is connected to the output of operational amplifier U2B and its inverting input. One end of resistor R9 is connected to the inverting input of operational amplifier U2A and one end of resistor R10, and the other end of resistor R9 is grounded. The other end of resistor R10 is connected to the output of operational amplifier U2A and one end of resistor R29. The other end of resistor R29 is connected to the non-inverting input of operational amplifier U2B.

2. The pyrotechnics testing equipment according to claim 1, characterized in that: The four-wire cable includes cable L1, cable L2, cable L3, and cable L4. One end of cable L1 is connected to the positive terminal of a constant current source, and the other end of cable L1 is connected to the positive terminal of a pyrotechnic device. One end of cable L2 is connected to the negative terminal of a constant current source, and the other end of cable L2 is connected to the negative terminal of a pyrotechnic device. One end of cable L3 is connected to the positive input terminal of a voltage amplifier, and the other end of cable L3 is connected to the positive terminal of a pyrotechnic device. One end of cable L4 is connected to the negative input terminal of a voltage amplifier, and the other end of cable L4 is connected to the negative terminal of a pyrotechnic device.

3. The pyrotechnics testing equipment according to claim 1, characterized in that: The output current and voltage protection circuit includes resistor R33, resistor R50 and Zener diode V1. One end of resistor R33 is connected to one end of resistor R50, and the other end of resistor R33 is connected to the positive terminal of constant current source. The other end of resistor R50 is connected to the output port of constant current source and Zener diode V1.

4. The pyrotechnics testing equipment according to claim 1, characterized in that: The signal isolation output circuit includes an optical isolator chip U9, a pull-up resistor R49, a light-emitting diode D5, and a pull-up resistor R56. The positive output terminal of the optical isolator chip U9 is connected to the output interface TXD terminal, and the negative output terminal of the optical isolator chip U9 is grounded. One end of the pull-up resistor R49 is connected to the power supply VCC, and the other end of the pull-up resistor R49 is connected to the positive input terminal of the optical isolator chip U9. The negative terminal of the light-emitting diode D5 is connected to the negative input terminal of the optical isolator chip U9, and the positive terminal of the light-emitting diode D5 is connected to one end of the pull-up resistor R56. The other end of the pull-up resistor R56 is connected to the power supply 3V3.

5. The pyrotechnics testing equipment according to claim 1, characterized in that: The voltage acquisition and amplification circuit includes an operational amplifier U8A, resistors R41, R42, R47, R27, R61, capacitors C19 and C11. One end of resistor R41 is connected to the positive terminal of the pyrotechnic device, and the other end of resistor R41 is connected to the non-inverting input terminal of operational amplifier U8A and one end of resistor R61. The other end of resistor R61 is grounded. One end of resistor R47 is connected to the negative terminal of the pyrotechnic device, and the other end of resistor R47 is connected to the inverting input terminal of operational amplifier U8A and one end of resistor R27. The other end of resistor R27 is connected to the output terminal of operational amplifier U8A and one end of resistor R42. The other end of resistor R42 is connected to one end of capacitor C11, and the other end of capacitor C11 is grounded. One end of capacitor C19 is connected to the positive power supply of operational amplifier U8A, and the other end of capacitor C19 is grounded.

6. The pyrotechnics testing equipment according to claim 1, characterized in that: The AD conversion circuit includes an AD conversion chip, resistors R22, R8, R11, R3, R7, and capacitor C9. One end of resistor R22 is connected to a 3V3 power supply, and the other end of resistor R22 is connected to the RDY pin of the AD conversion chip. One end of resistor R8 is connected to one end of resistor R3, and the other end of resistor R8 is connected to the SCL pin of the AD conversion chip. The other end of resistor R3 is connected to a 3V3 power supply. One end of resistor R11 is connected to one end of resistor R7, and the other end of resistor R11 is connected to the SDA pin of the AD conversion chip. The other end of resistor R7 is connected to a 3V3 power supply. One end of capacitor C9 is connected to the VDD pin of the AD conversion chip, and the other end of capacitor C9 is grounded.

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