A linker separation time measurement circuit and a measurement method thereof

Abstract

This invention discloses a connector separation time measurement circuit, comprising an external interface unit, a power management unit, a start-up trigger unit, a separation detection unit, a control and timing unit, an output unit, and a linkage protection unit. The external interface unit includes a power input interface, an ignition signal interface, and a detection interface. The ignition signal interface is connected to the linkage protection unit, and the detection interface is connected to the separation detection unit. The control and timing unit is connected to the start-up trigger unit, the separation detection unit, the linkage protection unit, and the output unit, respectively. This circuit integrates separation event sensing, high-precision time measurement, result processing, and display into a portable host. The highly integrated system is not only highly portable but also possesses an independent and complete testing system. The final result is directly displayed on the screen, improving testing efficiency and reducing the overall cost and barrier to entry for users.

Description

Technical Field

[0001] This invention relates to a circuit for measuring the separation time of a connector and a method thereof. Background Technology

[0002] Currently, measuring the separation time of connecting components is a key performance indicator required in aerospace, defense, high-end equipment manufacturing, and scientific research fields for processes such as rocket stage separation, special mechanical mechanism disengagement, electrical connector separation, and relay contact disconnection. These processes are time-sensitive and crucial for performance evaluation. Existing separation time measurement devices are designed for specific separation physics principles, and specialized measurement systems have been developed. For connections that rely on circuit switching to achieve separation or signal switching, the industry has developed a mature and standard measurement paradigm, the core of which is the "break detection method". This method establishes an electrical circuit on the conductive components on both sides of the separation interface and monitors its continuity to determine the moment of separation. Based on this principle, various test boards, modules, or dedicated signal sources that need to be connected to an oscilloscope have been developed. These solutions essentially provide a "measurement function module" rather than a complete and independent "measurement instrument". Users must connect it to a general measurement or analysis system (such as an oscilloscope or data acquisition system) to obtain the final results.

[0003] For connected bodies that rely on other physical principles such as mechanical displacement, optical blocking, and pressure release for separation, completely different sensing technologies (such as laser ranging, high-speed photography, and pressure sensors) and a separate set of dedicated acquisition and processing systems must be used.

[0004] This "one principle, one system" approach leads to fragmented testing resources, low equipment utilization, and operators needing to master multiple systems. Most importantly, it lacks a portable terminal tool that truly meets the need for rapid, convenient, and direct high-precision results in the field. There is an urgent need in engineering fields to "package" laboratory-level measurement capabilities into a dedicated device that is ready to use out of the box and provides immediate results, even if its initial version is designed for the separation measurement of conductive connectors, which has the broadest demand.

[0005] For example, the electrical connector separation time measurement device, system and method disclosed in CN109000919A improves the accuracy and reliability of the measurement under this principle by optimizing the circuit design, signal judgment or anti-interference capability. It exists in the form of board, component or requires external power supply and signal output line. Its final output is an analog voltage jump signal observed by equipment such as oscilloscope, or a digital signal that needs to be transmitted to the host computer software for processing. It does not build a terminal instrument with complete human-computer interaction and can independently output the final measurement result. Moreover, its function is modular and not an independent instrument. It must rely on external general measurement equipment (such as oscilloscope, data acquisition instrument) and host computer software to form a complete measurement system. It cannot be used as a terminal device that can be used out of the box and directly display the result. This increases the system complexity, cost and deployment time.

[0006] Moreover, the results are delayed and rely on manual analysis. Users need to observe the oscilloscope waveform or analyze the acquired data, manually identify the transition points and calculate the time interval. This process is inefficient, carries the risk of subjective error, and cannot provide definite numerical results on-site immediately.

[0007] The system has poor portability and integration; the measurement system consisting of "dedicated module + oscilloscope + computer" is bulky, has complex wiring, high power consumption, is difficult to integrate into the device under test for in-situ testing, and is not convenient to carry to field environments such as field, launch site or production line for rapid testing.

[0008] The operation is difficult and the user experience is not user-friendly. The entire measurement process requires professional technicians to operate multiple devices and perform data analysis, which requires high skills from users and cannot achieve the simple experience of "one-click measurement and direct reading" like a multimeter. Summary of the Invention

[0009] The purpose of this invention is to address the problems of existing measuring devices being unable to perform independent measurements and having high user barriers by providing a highly integrated portable measuring instrument. This instrument integrates separation signal sensing, high-precision time measurement, intelligent processing, and result display into a single host, thereby simplifying the complex laboratory measurement process into a single-step "trigger-reading" operation for field engineers. This achieves portability, intuitiveness, and intelligence in high-precision separation time measurement.

[0010] The technical solution of the present invention: A connector separation time measurement circuit includes an external interface unit, a power management unit, a start-up trigger unit, a separation detection unit, a control and timing unit, an output unit, and a linkage protection unit. The external interface unit includes a power input interface, an ignition signal interface, and a detection interface. The ignition signal interface is connected to the linkage protection unit, and the detection interface is connected to the separation detection unit. The control and timing unit is connected to the start-up trigger unit, the separation detection unit, the linkage protection unit, and the output unit, respectively. The power input interface is connected to the power management unit, and the power management unit supplies power to each unit.

[0011] The control and timing unit includes a DSP. The DSP's GPIOA0 pin is connected to the linkage protection unit, the GPIOA1 pin is connected to the start trigger unit, the GPIOA2 pin is connected to the detection unit, and the GPIOB0~GPIOB7 pins, GPIOA6 and GPIOA7 pins, as well as the SCIRXDA and SCITXDA pins are connected to the output unit.

[0012] The start-up trigger unit includes a switch K, current-limiting resistors R4 and R5, and an optocoupler U1. One end of the switch K is connected to the positive terminal of the power input interface, and the other end is connected to one end of the current-limiting resistor R4. The other end of the current-limiting resistor R4 is connected to the positive terminal of the output of the optocoupler U1. The positive terminal of the output of the optocoupler U1 is connected to the GPIOA1 pin of the DSP. The negative terminal of the output of the optocoupler U1 is grounded, and the negative terminal of the input is connected to the negative terminal of the power input interface. A resistor R5 is also connected in parallel between the input terminals of the optocoupler U1.

[0013] The separation detection unit includes an optocoupler U2. The positive terminal of the input of the optocoupler U2 is connected to the detection interface XJC12, and the negative terminal of the input is grounded. A resistor R8 is also connected in parallel between the input terminals. The positive terminal of the output of the optocoupler U2 is connected to the GPIOA2 pin of the DSP, and the positive terminal of the output is grounded. The detection port XJC11 is connected to the power management unit through a resistor R7.

[0014] The linkage protection unit includes a solid-state relay K1. One end of the coil of the solid-state relay K1 is connected to the power management unit, and the other end is connected to the collector of the transistor Q1. One end of the contact of the solid-state relay K1 is connected to the positive terminal of the power input interface, and the other end of the contact of the solid-state relay K1 is connected to the positive terminal XDH+ of the ignition signal interface through a resistor. The negative terminal XDH of the ignition signal interface is connected to the negative terminal of the power input interface. The emitter of the transistor Q1 is grounded, and the base is connected to the GPIOA0 pin of the DSP through a resistor R3. A resistor R2 and a capacitor C1 are connected in parallel between the base and emitter of the transistor Q1.

[0015] The power management unit includes a DC / DC module and a voltage regulator chip LDO. The input terminal of the DC / DC module is connected to a 27V power supply via a power input interface. The positive terminal of the output terminal outputs a +5V power supply, which is connected to a ferrite bead L2 and the voltage regulator chip LDO respectively. The negative terminal of the output terminal is grounded through a ferrite bead L1. The ferrite bead L2 is connected to a resistor R7. The voltage regulator chip LDO outputs 3.3V and 1.8V power supplies. The 3.3V power supply is connected to the positive terminals of the output terminals of optocouplers U1 and U2 respectively via resistors R6 and R9. The 1.8V power supply is connected to the DSP.

[0016] The output unit includes a communication chip U5 and an LCD. The communication chip U5 is connected to the SCIRXDA and SCITXDA pins of the DSP. The LCD is connected to the driver chip U4 and the driver chip U3 respectively. The driver chip U4 is connected to the GPIOB0~GPIOB7 pins of the DSP. The chip U3 is connected to the GPIOA6 and GPIOA7 pins of the DSP.

[0017] A method for measuring connector separation time includes the following steps: S1. Power-on initialization: The external 27V power supply is converted to 5V by the DC / DC module, and then regulated to 3.3V / 1.8V by the LDO to power the DSP, optocoupler, driver chip and communication chip. S2. Start measurement: Press switch K to drive optocoupler U1 to conduct and output a rising edge signal to the DSP's GPIOA1 pin. After the DSP responds, it starts the internal timing module to begin counting. S3. Separation Detection: Connect both ends of the conductive connector under test to the detection interfaces XJC11 and XJC12. When the connector is not separated, the detection circuit is on, and the corresponding optocoupler U2 outputs a low level to the GPIOA2 pin of the DSP. When the connector is separated, the circuit is broken, the optocoupler U1 is cut off, and a rising edge trigger signal is output to the GPIOA2 pin of the DSP. S4. Timestamp Latch: After the DSP detects the rising edge of the GPIOA2 pin, it immediately latches the current timer counter value to obtain the timestamp of the separated event. S5. Time Calculation: The DSP calculates the separation time interval Δt based on the difference between the start timestamp and the separation timestamp, combined with the system clock cycle. S6. Result Output: The calculated separation time value is converted by the driver chip and sent to the LCD for display, or uploaded to the host computer through the RS422 communication chip; The formula for calculating the separation time interval Δt in S5 is as follows: Δt=(N end -N start )×T clk Where, N startN is the count value at the time of triggering. end T is the count value when the separation is triggered. clk This represents the DSP system clock cycle.

[0018] It also includes linkage protection: if the ignition linkage function is configured, the DSP controls the GPIOA0 pin to output a low level after detecting a separation event, driving the solid-state relay to cut off the ignition signal.

[0019] The beneficial effects of this invention are: it integrates the perception of separate events, high-precision time measurement, result processing and display into a portable host, which is highly integrated, not only highly portable, but also has an independent and complete testing system. The final results are displayed directly on the screen, which not only improves testing efficiency, but also reduces the total cost and threshold for users. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the measurement circuit of the present invention; Figure 2 This is a schematic diagram of the external structure of the measuring device of the present invention. Detailed Implementation

[0021] The connector separation time measurement circuit of the present invention uses DSP as the control and timing core, combined with optocoupler isolation, DC / DC and LDO voltage regulation, solid-state relay protection, LCD display and RS422 communication, to realize independent, high-precision and portable measurement of the separation time of conductive connectors.

[0022] The power management unit works as follows: An external 27V DC power supply is connected to the DC / DC module via the power input interface, converting 27V into a stable +5V output; one path of the +5V power supply provides the detection voltage to the discrete detection unit via the ferrite bead L2, and the other path is input to the voltage regulator chip LDO, which outputs 3.3V and 1.8V respectively; 3.3V powers the output sides of optocouplers U1 and U2, driver chips U3 and U4, and communication chip U5; 1.8V powers the DSP core, ensuring stable operation of the DSP; ferrite beads L1 and L2 suppress power ripple and electromagnetic interference, improving the circuit's anti-interference capability.

[0023] Working principle of the start-up trigger unit: The start-up trigger unit adopts an optocoupler isolation design to avoid external interference affecting the DSP. When switch K is pressed, the 27V power supply drives the input side of optocoupler U1 to conduct through the current-limiting resistor R4, and the output side is subsequently turned on, outputting a rising edge trigger signal to the DSP's GPIOA1 pin; resistor R5 is a shunt resistor on the input side of optocoupler U1 to prevent overcurrent damage to the device. After the DSP detects the rising edge of GPIOA1, it immediately starts the internal high-precision timing module to begin counting.

[0024] Working principle of the separation detection unit: The separation detection unit determines the moment of separation of the connector by means of a broken wire detection method. The detection interfaces XJC11 and XJC12 are connected to the conductive connector under test: When the connector is not separated, the detection circuit is on, the input side of the optocoupler U2 is energized and conducts, and the output side outputs a low level to the GPIOA2 pin of the DSP; at the moment of separation, the detection circuit is broken, the input side of the optocoupler U2 is de-energized and cut off, and the output side outputs a rising edge trigger signal to the GPIOA2 pin of the DSP; Resistor R7 provides a pull-up voltage for the detection circuit, and resistor R8 protects the input side of the optocoupler U2 to prevent overvoltage breakdown.

[0025] Working principle of the control and timing unit: The DSP, as the core controller, undertakes all functions of signal acquisition, timing, calculation, control, and output: It receives the rising edge of the start trigger unit, starts timing, and latches the start count value Nstart; it acquires the level signal of the separation detection unit in real time, and latches the separation count value Nend when a rising edge is detected; it calculates the separation time according to the formula Δt=(Nend-Nstart)×Tclk, where Tclk is the DSP system clock cycle; it controls the linkage protection unit to execute the ignition signal cutoff and drives the output unit to display and upload data.

[0026] Working principle of the linkage protection unit: The linkage protection unit is used for ignition linkage safety protection in aerospace and military scenarios. After the DSP detects the separation event, it controls the GPIOA0 pin to output a low level, the base of transistor Q1 is de-energized and cut off, the coil of solid relay K1 is de-energized, the contacts open, and the power supply circuit of the ignition signal interface is automatically cut off to avoid erroneous ignition action after separation; resistor R2 and capacitor C1 form an RC filter circuit to prevent interference signals from erroneously triggering transistor Q1.

[0027] Output unit working principle: The output unit realizes a dual output mode of local display + remote upload: Local display: The DSP's GPIOB0~GPIOB7, GPIOA6, and GPIOA7 pins are converted by driver chips U3 and U4 to drive the LCD to display the separation time value in real time; Remote upload: The DSP's SCIRXDA and SCITXDA pins are converted into RS422 signals by communication chip U5 and uploaded to the host computer for storage and analysis.

[0028] Example: This example uses the measurement of rocket electrical connector separation time as an application scenario. The specific measurement steps are as follows: Step 1: Hardware wiring and power-on 1. Connect an external 27V power supply to the circuit's power input interface to complete the power supply; 2. Connect the wires at both ends of the rocket electrical connector to the detection interfaces XJC11 and XJC12 respectively; 3. If ignition linkage protection is required, connect the ignition signal to the ignition signal interface XDH+ or XDH; 4. After power-on, the power management unit outputs 5V, 3.3V, and 1.8V, the DSP completes initialization, and the LCD displays "Standby".

[0029] Step 2: Start Measurement Press the start trigger unit switch K, the optocoupler U1 is turned on, the DSP's GPIOA1 pin detects the rising edge, the internal timing module starts, and latches the current counter value N. start =125000.

[0030] Step 3: Separation Trigger and Signal Acquisition. Manual or mechanical triggering separates the rocket's electrical connector. At the moment of separation, the detection circuit breaks, optocoupler U2 is cut off, and the DSP's GPIOA2 pin detects a rising edge, immediately latching the separation moment counter value N. end =250000.

[0031] Step 4: Separation Time Calculation Let the DSP system clock period T be... clk =10ns (100MHz clock), substituting into the formula: Δt=(N end -N start )×T clk =(250000-125000)×10ns=1250000ns=1.25ms.

[0032] Step 5: Result Output and Linkage Protection 1. The DSP sends the calculated 1.25ms to the LCD, and the screen directly displays "Separation Time: 1.25ms"; 2. Simultaneously, the data is uploaded to the host computer via an RS422 communication chip to complete data retention; 3. If the ignition linkage function is enabled, the DSP controls GPIOA0 to output a low level, the solid-state relay K1 is disconnected, the ignition signal is cut off, and the safety protection is completed.

[0033] Step 6: Measurement Completion After a single measurement is completed, the LCD retains the displayed result. The next measurement can be started by pressing switch K again, enabling continuous and rapid detection. In this embodiment, the circuit does not require external oscilloscopes, data acquisition instruments, or other equipment. It features one-button triggering and direct reading, achieving nanosecond-level measurement accuracy, meeting the high-precision, portable measurement needs of aerospace, military, and other scenarios.

Claims

1. A connector separation time measurement circuit, characterized in that: It includes an external interface unit, a power management unit, a start-up trigger unit, a separation detection unit, a control and timing unit, an output unit, and a linkage protection unit. The external interface unit includes a power input interface, an ignition signal interface, and a detection interface. The ignition signal interface is connected to the linkage protection unit, and the detection interface is connected to the separation detection unit. The control and timing unit is connected to the start-up trigger unit, the separation detection unit, the linkage protection unit, and the output unit, respectively. The power input interface is connected to the power management unit, and the power management unit supplies power to each unit.

2. The connector separation time measurement circuit according to claim 1, characterized in that: The control and timing unit includes a DSP. The DSP's GPIOA0 pin is connected to the linkage protection unit, the GPIOA1 pin is connected to the start trigger unit, the GPIOA2 pin is connected to the detection unit, and the GPIOB0~GPIOB7 pins, GPIOA6 and GPIOA7 pins, as well as the SCIRXDA and SCITXDA pins are connected to the output unit.

3. The connector separation time measurement circuit according to claim 1, characterized in that: The start-up trigger unit includes a switch K, current-limiting resistors R4 and R5, and an optocoupler U1. One end of the switch K is connected to the positive terminal of the power input interface, and the other end is connected to one end of the current-limiting resistor R4. The other end of the current-limiting resistor R4 is connected to the positive terminal of the output of the optocoupler U1. The positive terminal of the output of the optocoupler U1 is connected to the GPIOA1 pin of the DSP. The negative terminal of the output of the optocoupler U1 is grounded, and the negative terminal of the input is connected to the negative terminal of the power input interface. A resistor R5 is also connected in parallel between the input terminals of the optocoupler U1.

4. The connector separation time measurement circuit according to claim 1, characterized in that: The separation detection unit includes an optocoupler U2. The positive terminal of the input of the optocoupler U2 is connected to the detection interface XJC12, and the negative terminal of the input is grounded. A resistor R8 is also connected in parallel between the input terminals. The positive terminal of the output of the optocoupler U2 is connected to the GPIOA2 pin of the DSP, and the positive terminal of the output is grounded. The detection port XJC11 is connected to the power management unit through a resistor R7.

5. The connector separation time measurement circuit according to claim 1, characterized in that: The linkage protection unit includes a solid-state relay K1. One end of the coil of the solid-state relay K1 is connected to the power management unit, and the other end is connected to the collector of the transistor Q1. One end of the contact of the solid-state relay K1 is connected to the positive terminal of the power input interface, and the other end of the contact of the solid-state relay K1 is connected to the positive terminal XDH+ of the ignition signal interface through a resistor. The negative terminal XDH of the ignition signal interface is connected to the negative terminal of the power input interface. The emitter of the transistor Q1 is grounded, and the base is connected to the GPIOA0 pin of the DSP through a resistor R3. A resistor R2 and a capacitor C1 are connected in parallel between the base and emitter of the transistor Q1.

6. The connector separation time measurement circuit according to claim 1, characterized in that: The power management unit includes a DC / DC module and a voltage regulator chip LDO. The input terminal of the DC / DC module is connected to a 27V power supply via a power input interface. The positive terminal of the output terminal outputs a +5V power supply, which is connected to a ferrite bead L2 and the voltage regulator chip LDO respectively. The negative terminal of the output terminal is grounded through a ferrite bead L1. The ferrite bead L2 is connected to a resistor R7. The voltage regulator chip LDO outputs 3.3V and 1.8V power supplies. The 3.3V power supply is connected to the positive terminals of the output terminals of optocouplers U1 and U2 respectively via resistors R6 and R9. The 1.8V power supply is connected to the DSP.

7. The connector separation time measurement circuit according to claim 1, characterized in that: The output unit includes a communication chip U5 and an LCD. The communication chip U5 is connected to the SCIRXDA and SCITXDA pins of the DSP. The LCD is connected to the driver chip U4 and the driver chip U3 respectively. The driver chip U4 is connected to the GPIOB0~GPIOB7 pins of the DSP. The chip U3 is connected to the GPIOA6 and GPIOA7 pins of the DSP.

8. A method for measuring the separation time of a connector according to claims 1-7, comprising the following steps: S1. Power-on initialization: The external 27V power supply is converted to 5V by the DC / DC module, and then regulated to 3.3V / 1.8V by the LDO to power the DSP, optocoupler, driver chip and communication chip. S2. Start measurement: Press switch K to drive optocoupler U1 to conduct and output a rising edge signal to the DSP's GPIOA1 pin. After the DSP responds, it starts the internal timing module to begin counting. S3. Separation Detection: Connect both ends of the conductive connector under test to the detection interfaces XJC11 and XJC12. When the connector is not separated, the detection circuit is on, and the corresponding optocoupler U2 outputs a low level to the GPIOA2 pin of the DSP. When the connector is separated, the circuit is broken, the optocoupler U1 is cut off, and a rising edge trigger signal is output to the GPIOA2 pin of the DSP. S4. Timestamp Latch: After the DSP detects the rising edge of the GPIOA2 pin, it immediately latches the current timer counter value to obtain the timestamp of the separated event. S5. Time Calculation: The DSP calculates the separation time interval Δt based on the difference between the start timestamp and the separation timestamp, combined with the system clock cycle. S6. Result Output: The calculated separation time value is converted by the driver chip and sent to the LCD for display, or uploaded to the host computer through the RS422 communication chip.

9. The method for measuring the separation time of a connector according to claim 8, characterized in that: The formula for calculating the separation time interval Δt in S5 is as follows: Δt=(N end -N start )×T clk Where, N start N is the count value at the time of triggering. end T is the count value when the separation is triggered. clk This represents the DSP system clock cycle.

10. A method for measuring the separation time of a connector according to claim 8, characterized in that: It also includes linkage protection: if the ignition linkage function is configured, the DSP controls the GPIOA0 pin to output a low level after detecting a separation event, driving the solid-state relay to cut off the ignition signal.

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