Low current electric ignition head detection device

Abstract

The application discloses a low-current electric ignition head detection device, which comprises a constant current source, an amplifier, a voltage signal acquisition and output circuit and an upper computer. The constant current source is used for inputting a constant current power source with a preset size to the electric ignition head. The amplifier is used for detecting the voltage generated on the electric ignition head and amplifying the voltage by a preset multiple. The voltage signal acquisition and output circuit is used for carrying out analog-digital conversion on the voltage signal output by the amplifier to obtain a digital signal and transmitting the digital signal to the upper computer. The upper computer calculates the resistance of the electric ignition head according to the digital signal and the size of the constant current power source. The application adopts the mode of low constant current input, signal amplification, signal acquisition, AD conversion and output to the upper computer, so that the resistance data of the electric ignition head of the rocket can be obtained quickly, conveniently and safely before the rocket is launched, and the detection process is safe and quick.

Description

Technical Field

[0001] This invention relates to the field of rocket electric ignition head resistance safety testing technology, specifically to a low-current electric ignition head testing device. Background Technology

[0002] Before launch, rockets require testing the resistance parameters of the launch electric ignition head to determine if it is online and if its resistance is normal. Electric ignition heads generally have low resistance, around 2 ohms. The traditional method is to input a signal waveform to the positive terminal of the ignition head and collect this waveform at the negative terminal. However, this method can only test whether the ignition head is in the ignition circuit, but cannot accurately detect its resistance. Summary of the Invention

[0003] Technical Objective: To address the aforementioned technical problems, this invention proposes a low-current electric ignition head detection device. This device employs a low constant current input, followed by signal amplification, signal acquisition, and AD conversion before outputting to a host computer. This ensures that the rocket's electric ignition head resistance data can be obtained quickly, conveniently, and safely before launch, making the detection process safe and fast.

[0004] Technical solution: To achieve the above technical objectives, the present invention adopts the following technical solution:

[0005] A low-current electric ignition head detection device is characterized by comprising a constant current source, an amplifier, a voltage signal acquisition and output circuit, and a host computer. The constant current source is used to input a constant current power supply of a preset value to the electric ignition head. The amplifier is used to detect the voltage generated on the electric ignition head and amplify it by a preset factor. The voltage signal acquisition and output circuit is communicatively connected to the host computer and is used to perform analog-to-digital conversion on the voltage signal output by the amplifier to obtain a digital signal, which is then transmitted to the host computer. The host computer calculates the resistance of the electric ignition head based on the digital signal and the magnitude of the constant current power supply.

[0006] Preferably, the constant current source uses a constant current source chip LM234DT. The peripheral circuit of the constant current source chip LM234DT includes a sixth resistor, a second capacitor, a third resistor, a fifth resistor, and a diode 1N4148. The positive terminal of the constant current source chip LM234DT is connected to a +5V DC voltage via the sixth resistor and grounded via the second capacitor. The negative terminal of the constant current source chip LM234DT is connected to the positive terminal of the diode 1N4148, and the negative terminal of the diode 1N4148 is connected to one end of the ignition head, while the other end of the ignition head is grounded. The ADJ adjustment terminal of the constant current source chip LM234DT is connected to one end of the third resistor and one end of the fifth resistor. The other end of the third resistor is connected to the negative terminal of the diode 1N4148, and the other end of the fifth resistor is connected to the positive terminal of the diode 1N4148.

[0007] Preferably, the amplifier uses the AD8224A amplifier chip. The +IN1 terminal of the AD8224A amplifier chip is connected to the common connection terminal of the electric ignition head and the constant current source, the -IN1 terminal is grounded, the RFF1 terminal is connected to a 2.5V reference voltage, a fourth resistor R7 is provided between the RG1_1 and RG1_2 terminals, the -1VS_1 terminal is grounded, and a third capacitor is provided at the +VS_1 terminal. One end of the third capacitor is connected to a 3-5V DC voltage, and the other end is grounded. The OUT1 terminal of the AD8224A amplifier chip serves as the output terminal of the amplifier, outputting a voltage signal that has been amplified by a preset factor.

[0008] Preferably, the voltage signal acquisition and output circuit uses the AD7606BSTZ converter chip. The peripheral circuit of the AD7606BSTZ converter chip includes a first capacitor, a second resistor, and a fourth resistor. A first capacitor is located between the V1+ and V1- terminals of the AD7606BSTZ converter chip. One end of the first capacitor is connected to one end of the second resistor, and the other end of the second resistor is connected to the voltage signal output by the amplifier. The other end of the first capacitor is connected to one end of the fourth resistor, and the other end of the fourth resistor is grounded. The DOUTA terminal of the AD7606BSTZ converter chip is connected to the host computer via the SPI bus to transmit the digital signal obtained after digital-to-analog conversion to the host computer.

[0009] Beneficial effects: Due to the adoption of the above technical solution, the present invention has the following beneficial effects:

[0010] This invention employs a low constant current input, followed by signal amplification, signal acquisition, and AD conversion before outputting to the host computer. This ensures both the safety of the detection and the ability to quickly and conveniently communicate the detected resistance data to the host computer. Furthermore, this invention uses commercially available industrial chips, and the designed rocket electric ignition head detection solution is safe, fast, and can be easily integrated into modern rocket launch control systems. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the structure of a low-current electric ignition head detection device proposed in this invention;

[0012] Figure 2 This is a schematic diagram of the low-current electric ignition head detection device proposed in Example 1;

[0013] Figure 3 A circuit diagram illustrating a specific example of the constant current source proposed in Embodiment 1;

[0014] Figure 4 A circuit diagram of a specific example of the amplifier proposed in Embodiment 1;

[0015] Figure 5 Partial circuit of a specific example of a voltage signal acquisition and output circuit. Figure 1 ;

[0016] Figure 6 Partial circuit of a specific example of a voltage signal acquisition and output circuit. Figure 2 . Detailed Implementation

[0017] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0018] This invention relates to a low-current electric ignition head detection device, used to input a fixed milliampere-level current to the rocket's electric ignition head, then collect the millivolt voltage across the electric ignition head, amplify it using a precision instrument amplifier, and then output it to a host computer via an AD converter to detect the resistance of the ignition head, thereby meeting the requirements for measuring the resistance of the rocket's electric ignition head for safety. Figure 1 As shown, this device includes: a constant current source, an amplifier, a voltage signal acquisition and output circuit, and a host computer. The constant current source is used to input a constant current power supply of a preset value to the electric ignition head. The amplifier is used to detect the voltage generated on the electric ignition head and amplify it by a preset factor. The converter is used to perform analog-to-digital conversion on the voltage signal output by the amplifier to obtain a digital signal and transmit it to the host computer. The host computer calculates the resistance of the electric ignition head based on the digital signal and the magnitude of the constant current power supply.

[0019] When testing the resistance of the ignition head before rocket launch, it is necessary to ensure that it does not ignite safely. As a pyrotechnic device with a metal resistance heating wire, controlling the overcurrent of the electric ignition head is the core key to safety control.

[0020] Example 1

[0021] like Figures 2 to 6 As shown, this embodiment uses the LM234DT chip to design a 5mA constant current source input ignition head. The generated voltage signal is amplified by the AD822A precision instrumentation amplifier, and then collected by the AD7606BSTZ and output to the host computer via SPI communication, which solves the problem of ignition head resistance safety testing before rocket launch.

[0022] like Figure 3As shown, the constant current source uses the LM234DT (IC2) chip. The peripheral circuit of the LM234DT chip includes a sixth resistor R6, a second capacitor C2, a third resistor R3, a fifth resistor R5, and a diode 1N4148D1. The positive terminal of the LM234DT chip is connected to a +5V DC voltage via the sixth resistor R6 and grounded via the second capacitor C2. The negative terminal of the LM234DT chip is connected to the positive terminal of the diode 1N4148, and the negative terminal of the diode 1N4148 is connected to one end of the ignition head, while the other end of the ignition head is grounded. The ADJ adjustment terminal of the LM234DT chip is connected to one end of the third resistor R3 and one end of the fifth resistor R5. The other end of the third resistor R3 is connected to the negative terminal of the diode 1N4148, and the other end of the fifth resistor R5 is connected to the positive terminal of the diode 1N4148.

[0023] like Figure 4 As shown, the amplifier uses the AD8224A(IC1) amplifier chip. The +IN1 terminal of the AD8224A(IC1) amplifier chip is connected to the common connection terminal of the electric ignition head and the constant current source, the -IN1 terminal is grounded, the RFF1 terminal is connected to the 2.5V reference voltage, a fourth resistor R7 is provided between the RG1_1 terminal and the RG1_2 terminal, the -1VS_1 terminal is grounded, and a third capacitor C3 is provided at the +VS_1 terminal. One end of the third capacitor C3 is connected to the 3-5V DC voltage, and the other end is grounded. The OUT1 terminal of the AD8224A(IC1) amplifier chip serves as the output terminal of the amplifier, outputting a voltage signal that has been amplified by a preset factor.

[0024] like Figure 5 As shown, the converter uses the converter chip AD7606BSTZ(U1). The peripheral circuit of the converter chip AD7606BSTZ(U1) includes a first capacitor C1, a second resistor R2, and a fourth resistor R4. The first capacitor C1 is located between the V1+ and V1- terminals of the converter chip AD7606BSTZ(U1). One end of the first capacitor C1 is connected to one end of the second resistor R2. The other end of the second resistor R2 is connected to the voltage signal S2 output by the amplifier. The other end of the first capacitor C1 is connected to one end of the fourth resistor R4. The other end of the fourth resistor R4 is grounded.

[0025] like Figure 6 As shown, the DOUTA terminal of the converter chip AD7606BSTZ(U1) is connected to the host computer via the SPI bus to transmit the digital signal obtained by digital-to-analog conversion to the host computer.

[0026] In the solution of this invention, the constant current source current and amplifier factor can be adjusted according to actual needs, the AD7606BSTZ hardware settings can be configured, the AD7606BSTZ communication protocol can be familiarized, the host computer control timing can be designed, and the design state can be achieved by debugging in actual engineering.

[0027] In the device of the present invention, the output current of the constant current source is not limited to 5mA, and preferably the output current range is 5-10mA. Moreover, a control switch such as a MOS switch can be added between the constant current source and the electric ignition head. After the electric ignition head detection is completed, the connection between the constant current source and the electric ignition head is disconnected.

[0028] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the above embodiments do not limit the present invention in any way, and all technical solutions obtained by equivalent substitution or equivalent transformation fall within the protection scope of the present invention.

Claims

1. A low-current electric ignition head detection device, characterized in that, The system includes a constant current source, an amplifier, a voltage signal acquisition and output circuit, and a host computer. The constant current source is used to input a preset constant current power supply to the electric ignition head. The amplifier is used to detect the voltage generated on the electric ignition head and amplify it by a preset factor. The voltage signal acquisition and output circuit is communicatively connected to the host computer and is used to perform analog-to-digital conversion on the voltage signal output by the amplifier to obtain a digital signal, which is then transmitted to the host computer. The host computer calculates the resistance of the electric ignition head based on the digital signal and the magnitude of the constant current power supply. The constant current source uses a constant current source chip LM234DT (IC2). The peripheral circuit of the constant current source chip LM234DT includes a sixth resistor (R6), a second capacitor (C2), a third resistor (R3), a fifth resistor (R5), and a diode 1N4148 (D1). The positive terminal of the constant current source chip LM234DT is connected to a +5V DC voltage via the sixth resistor (R6). The circuit is grounded via the second capacitor (C2); the negative terminal of the constant current source chip LM234DT is connected to the positive terminal of diode 1N4148, the negative terminal of diode 1N4148 is connected to one end of the ignition head, and the other end of the ignition head is grounded; the ADJ adjustment terminal of the constant current source chip LM234DT is simultaneously connected to one end of the third resistor (R3) and one end of the fifth resistor (R5), the other end of the third resistor (R3) is connected to the negative terminal of diode 1N4148, and the other end of the fifth resistor (R5) is connected to the positive terminal of diode 1N4148 (D1); the amplifier uses amplifier chip AD8224A (IC1), the +IN1 terminal of amplifier chip AD8224A (IC1) is connected to the common connection terminal of the ignition head and the constant current source, the -IN1 terminal is grounded, the RFF1 terminal is connected to a 2.5V reference voltage, and a fourth resistor (R7) is provided between the RG1_1 and RG1_2 terminals. The -VS_1 terminal is grounded, and the +VS_1 terminal has a third capacitor (C3). One end of the third capacitor (C3) is connected to a 3-5V DC voltage, and the other end is grounded. The OUT1 terminal of the amplifier chip AD8224A (IC1) serves as the output terminal of the amplifier, outputting a voltage signal that has been amplified by a preset factor. The voltage signal acquisition and output circuit uses the converter chip AD7606BSTZ (U1). The peripheral circuit of the converter chip AD7606BSTZ (U1) includes a first capacitor (C1), a second resistor (R2), and a fourth resistor (R4). A first capacitor (C1) is provided between the V1+ and V1- terminals of the AD7606BSTZ(U1) chip. One end of the first capacitor (C1) is connected to one end of the second resistor (R2), and the other end of the second resistor (R2) is connected to the voltage signal (S2) output by the amplifier. The other end of the first capacitor (C1) is connected to one end of the fourth resistor (R4), and the other end of the fourth resistor (R4) is grounded. The DOUTA terminal of the converter chip AD7606BSTZ(U1) is connected to the host computer via the SPI bus to transmit the digital signal obtained by digital-to-analog conversion to the host computer.

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