CN114184187A - Device and method for improving debugging efficiency of digital demodulation circuit for fiber-optic gyroscope - Google Patents
Device and method for improving debugging efficiency of digital demodulation circuit for fiber-optic gyroscope Download PDFInfo
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- CN114184187A CN114184187A CN202111391899.0A CN202111391899A CN114184187A CN 114184187 A CN114184187 A CN 114184187A CN 202111391899 A CN202111391899 A CN 202111391899A CN 114184187 A CN114184187 A CN 114184187A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
- G01C19/00—Gyroscopes; Turn-sensitive devices using vibrating masses; Turn-sensitive devices without moving masses; Measuring angular rate using gyroscopic effects
- G01C19/58—Turn-sensitive devices without moving masses
- G01C19/64—Gyrometers using the Sagnac effect, i.e. rotation-induced shifts between counter-rotating electromagnetic beams
- G01C19/72—Gyrometers using the Sagnac effect, i.e. rotation-induced shifts between counter-rotating electromagnetic beams with counter-rotating light beams in a passive ring, e.g. fibre laser gyrometers
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Abstract
The invention discloses a device and a method for improving debugging efficiency of a digital demodulation circuit for a fiber-optic gyroscope. The device comprises a test tool circuit and an industrial personal computer; the test tool circuit comprises a circuit board, a spring probe and a copper column, wherein the spring probe and the copper column are arranged on the circuit board; the copper column is used for mounting a digital demodulation circuit board to be tested; the spring probes are divided into two groups in different areas, one group of spring probes is used for connecting a front amplifying/filtering module and a feedback driving module in the digital demodulation circuit to be tested, and the other group of spring probes is used for supplying power and serial port data communication; the industrial personal computer is in signal connection with the serial port module in the digital demodulation circuit to be tested. During debugging: the debugging of the digital demodulation circuit to be tested is completed by combining a digital closed-loop debugging program in the FPGA control module of the digital demodulation circuit to be tested with an upper computer testing program running in an industrial personal computer, a function generator, a digital oscilloscope and other equipment are not needed in the whole debugging process, the operation is simple, and the method is particularly suitable for the mass production of the gyroscope.
Description
Technical Field
The invention relates to an optical fiber gyroscope, in particular to a device and a method for improving debugging efficiency of a digital demodulation circuit for an optical fiber gyroscope.
Background
The Fiber Optic Gyroscope (FOG) is a novel all-solid-state inertial instrument for measuring angular rate by utilizing the Sagnac effect, compared with the traditional electromechanical gyroscope, the FOG has the advantages of small volume, low cost, long service life, wide dynamic range, short starting time and the like, through more than 40 years of development, the fiber optic gyroscope technology is completely mature, the precision covers 10 degrees/h-0.0001 degrees/h, and the FOG is most widely applied. The demand of the current optical fiber gyroscope is continuously increased, and great challenges are brought to the production and delivery of the optical fiber gyroscope.
The optical fiber gyroscope mainly comprises a light path part and a circuit part, wherein the light path part mainly comprises a light source, a detector, an optical fiber coupler, a phase modulator, an optical fiber ring and the like, and the circuit mainly comprises a digital demodulation circuit and a light source driving circuit. The structure composition is shown in figure 1.
When the gyroscope rotates, a phase difference is generated between two beams of light which are reversely transmitted by the optical fiber ring, a signal with a proportional rotating speed can be obtained through the phase difference, and the digital demodulation circuit part completes the functions of detection and demodulation of an optical interference signal, closed-loop feedback control, angular speed output and the like.
The digital demodulation circuit consists of a preamplifier/filter module, an A/D conversion module, an FPGA control module, a D/A conversion module, a feedback drive module and a serial port module, and the functional block diagram of the digital demodulation circuit is shown in figure 2. The front amplifier/filter circuit module is used for amplifying the signal subjected to photoelectric conversion with low noise so as to meet the input range requirement of the A/D converter; the A/D conversion module is used for converting the amplified analog signals into digital signals; taking the FPGA as a core control module, carrying out digital demodulation on an input digital signal to acquire accurate information of the rotating speed, and then carrying out digital filtering on the information and generating a feedback signal parameter; the D/A conversion module is used for converting the formed digital feedback modulation signal into an analog signal; the feedback driving module amplifies and feeds the analog signal back to the Y waveguide to be used as a modulation signal of phase bias modulation and step wave modulation.
The traditional debugging method is to weld a lead into an external interface bonding pad of the digital demodulation circuit board to be tested to realize the power supply and signal connection of the digital demodulation circuit board to be tested, and the debugging steps are as follows:
the debugging steps of the conventional debugging method are as follows:
firstly, welding a lead into an external interface bonding pad of the digital demodulation circuit board to be tested to realize power supply and signal connection of the digital demodulation circuit board to be tested;
downloading a DA debugging program, debugging the D/A conversion module and the feedback driving module, observing the output of the feedback driving module through a digital oscilloscope and manually filling a test result;
downloading an AD debugging program, generating a sine signal as an input signal through a function generator, debugging a preamplifier/filter module and an A/D conversion module, observing the output of a feedback driving module through a digital oscilloscope and manually filling a test result;
fourthly, debugging the serial port module, namely short-circuiting a differential line of the serial port, downloading a serial port debugging program, observing the on and off of an indicator light of the digital demodulation circuit to be tested, and manually filling a test result;
and fifthly, welding off the lead of the digital demodulation circuit board to be tested, and cleaning the welding disc.
The function generator, the digital oscilloscope, the electric soldering iron and other equipment are needed to be used in the whole debugging process, the conducting wire needs to be welded firstly during debugging, and after the debugging is completed, the conducting wire needs to be welded off, and the welding pad needs to be cleaned. The whole debugging process is time-consuming and labor-consuming, and the efficiency is lower.
Disclosure of Invention
The invention provides a device and a method for improving the debugging efficiency of a digital demodulation circuit for a fiber-optic gyroscope, aiming at the problem that the debugging efficiency of the digital demodulation circuit in the gyroscope is low by the traditional debugging method.
The specific technical scheme of the invention is as follows:
the utility model provides an improve device of digital demodulation circuit debugging efficiency for fiber-optic gyroscope which characterized in that: the test device comprises a test tool circuit and an industrial personal computer;
the test tool circuit comprises a circuit board, a spring probe and a copper column, wherein the spring probe and the copper column are arranged on the circuit board;
the copper column is used for mounting a digital demodulation circuit board to be tested;
the spring probes are divided into two groups in different areas, one group of spring probes is used for connecting a front amplifying/filtering module and a feedback driving module in the digital demodulation circuit to be tested, and the other group of spring probes is used for supplying power and serial port data communication;
the industrial personal computer is in signal connection with the serial port module in the digital demodulation circuit to be tested, and an upper computer test program running on the industrial personal computer is used for receiving data sent by the digital demodulation circuit to be tested, interpreting the data and recording a test data result.
Further, the test tool circuit is further provided with an external outgoing line and a connector, wherein the external outgoing line and the connector are used for being connected with an industrial personal computer and an external power supply.
Based on the above description of the structure of the debugging apparatus, a method for debugging by using the debugging apparatus is introduced, and the specific implementation steps are as follows:
step 1: installing a digital demodulation circuit to be tested on a test tool circuit, realizing signal connection between the digital demodulation circuit to be tested and the test tool circuit through a spring probe, and respectively connecting the digital demodulation circuit to be tested with an industrial personal computer and an external power supply;
step 2: generating a first sinusoidal signal through an FPGA control module of a digital demodulation circuit to be tested, outputting the initial sinusoidal signal from a feedback driving module after passing through a D/A conversion module of the digital demodulation circuit to be tested, enabling the output signal to enter a front amplifier/filter module of the digital demodulation circuit to be tested through a spring probe of a test tool circuit, then entering an A/D conversion module, and finally returning to an RAM of the FPGA control module for storage;
and step 3: the FPGA control module receives instruction information sent by a program of an upper computer in the industrial personal computer, signals stored in the RAM are sent to the industrial personal computer through the serial port module, the industrial personal computer draws and displays a second sinusoidal signal, and whether corresponding change is generated or not in comparison with the first sinusoidal signal by judging the amplitude of the second sinusoidal signal, so that closed-loop debugging of the digital demodulation circuit to be tested is realized.
The invention has the beneficial effects that:
compared with the prior art, the hardware realizes the electrical connection between the test tool circuit and the digital demodulation circuit to be tested through the spring probe; a digital closed-loop debugging program is designed in an FPGA control module of the digital demodulation circuit to be tested on software in combination with an upper computer test program running in an industrial personal computer, the digital demodulation circuit to be tested is debugged through the two programs, a function generator, a digital oscilloscope and other equipment are not needed in the whole debugging process, the operation is simple, and the method is particularly suitable for large-batch production of the gyroscope.
Drawings
Fig. 1 is a schematic structural diagram of a conventional optical fiber gyroscope.
Fig. 2 is a schematic diagram of a digital demodulation circuit in a gyroscope.
Fig. 3 is a signal transmission diagram after the test fixture circuit is connected with the digital demodulation circuit.
Fig. 4 is a schematic structural diagram of a test fixture circuit.
Fig. 5 is a flow chart of the FPGA program operation.
Fig. 6 is a waveform diagram of a sinusoidal signal displayed in the upper computer.
Fig. 7 is a flowchart of the operation of the upper computer program.
The reference numbers are as follows:
1-circuit board, 2-spring probe, 3-copper column, 4-external outgoing line and 5-connector.
Detailed Description
The technical solution of the present invention will be described in more detail with reference to the accompanying drawings.
The basic idea of the invention is as follows:
1. manufacturing a test tool circuit, and realizing power supply and data interaction of the digital demodulation circuit to be tested through the test tool circuit;
2. compiling a digital closed-loop debugging program in an FPGA control module of the digital demodulation circuit to be tested, and completing the debugging of each module of the digital demodulation circuit at one time;
3. and compiling an upper computer test program in the industrial personal computer, receiving data in a serial port module in the digital demodulation circuit to be tested, and finishing the interpretation and recording of the result of the data, thereby realizing the debugging of the digital demodulation circuit.
The debugging device of the invention realizes the debugging of the digital demodulation circuit to be tested by a testing tool circuit and an industrial personal computer, the hardware core component of the debugging device is the testing tool circuit, and the structure of the circuit is shown in figure 4 and comprises a circuit board 1 (PCB), a spring probe 2, a copper column 3, an external outgoing line 4 and a connector 5;
during debugging, the digital demodulation circuit to be tested can be installed on the circuit board 1 through the copper column 3;
the spring probes 2 are divided into two groups and are respectively arranged in two areas of the circuit board 1, and one group of spring probes is used for connecting a front amplifier/filter module and a feedback drive module (namely an area A in the graph 4) in the digital demodulation circuit to be tested; the other group of spring probes is used for power supply and serial data communication (namely, a B area in fig. 4);
the circuit board 1 is connected with an industrial personal computer and an external power supply through an external outgoing line 4 and a connector 5;
the industrial personal computer is in signal connection with the serial port module in the digital demodulation circuit to be tested, and an upper computer test program running on the industrial personal computer is used for receiving data sent by the digital demodulation circuit to be tested, interpreting the data and recording a test data result.
The specific debugging process of the debugging device is as follows:
generating a first sinusoidal signal through an FPGA control module of a digital demodulation circuit to be tested, outputting the initial sinusoidal signal from a feedback driving module after the initial sinusoidal signal passes through a D/A conversion module of the digital demodulation circuit to be tested, enabling the output signal to enter a front amplifier/filter module of the digital demodulation circuit to be tested through a spring probe of a test tool circuit, then entering an A/D conversion module, and finally returning to an RAM of the FPGA control module for storage;
the FPGA control module receives instruction information sent by a program of an upper computer in the industrial personal computer, signals stored in the RAM are sent to the industrial personal computer through the serial port module, the industrial personal computer draws and displays a second sinusoidal signal, and whether corresponding change is generated or not in comparison with the first sinusoidal signal by judging the amplitude of the second sinusoidal signal, so that closed-loop debugging of the digital demodulation circuit to be tested is realized.
The digital closed-loop debugging program running in the FPGA control module is an important part for rapid debugging, and realizes the closed-loop debugging of each module of the digital demodulation circuit, and the specific running flow of the digital closed-loop debugging program is shown in figure 5:
a1: generating a discrete data file of a sinusoidal signal through MATLAB;
a2: writing a discrete data file of the sinusoidal signal into an RAM of an FPGA chip;
a3: outputting the data in the RAM to a D/A conversion module according to a certain clock frequency so as to convert the digital signals into analog signals;
a4: the analog signal enters an A/D conversion module through a spring probe on a test tool circuit and is stored in an RAM of an FPGA control module;
a5: and after receiving the instruction sent by the upper computer, the FPGA control module sends the data in the RAM to the upper computer.
The upper computer test program running in the industrial personal computer has a specific running flow as shown in fig. 7:
the industrial personal computer is communicated with the FPGA control module through the serial port module, receives data sent by the FPGA control module after sending an instruction to the FPGA control module, and then performs drawing and displaying of a waveform diagram of a sinusoidal signal; and judging the sinusoidal signal by clicking a data interpretation button on the test program of the upper computer, wherein the sinusoidal signal is qualified to indicate that each module of the digital demodulation circuit to be tested has normal functions, and then printing a debugging report.
As can be seen from the above description, the present invention improves debugging efficiency in three aspects:
1. the electrical connection of the digital demodulation circuit to be tested is realized in a mode of not welding a lead;
2. performing signal processing operation once to complete closed-loop debugging of all functional modules of the digital demodulation circuit to be tested;
3. and interpreting the debugging data through an upper computer test program, and generating a debugging report.
In order to further prove that the method of the invention really and greatly improves the debugging efficiency of the digital demodulation circuit, the invention also provides the following comparison test:
the conventional debugging method is compared with the method of the present invention by time cost data required to debug a block of circuitry. The comparison results are shown in table 1:
TABLE 1
| Traditional debugging method | New debugging method using device | |
| Time to weld wire and clean up time | 15min | 0min |
| Time required for debugging a circuit | 25min | 3min |
| Data result recording requires time | 5min | 1min |
| The total time required to debug a circuit | 45min | 4min |
As can be seen from Table 1, the method of the present invention saves more than 10 times of time compared with the conventional method, and greatly improves the debugging efficiency.
Claims (3)
1. The utility model provides an improve device of digital demodulation circuit debugging efficiency for fiber-optic gyroscope which characterized in that: the test device comprises a test tool circuit and an industrial personal computer;
the test tool circuit comprises a circuit board, a spring probe and a copper column, wherein the spring probe and the copper column are arranged on the circuit board;
the copper column is used for mounting a digital demodulation circuit board to be tested;
the spring probes are divided into two groups in different areas, one group of spring probes is used for connecting a front amplifying/filtering module and a feedback driving module in the digital demodulation circuit to be tested, and the other group of spring probes is used for supplying power and serial port data communication;
the industrial personal computer is in signal connection with the serial port module in the digital demodulation circuit to be tested, and an upper computer test program running on the industrial personal computer is used for receiving data sent by the digital demodulation circuit to be tested, interpreting the data and recording a test data result.
2. The apparatus for improving the debugging efficiency of the digital demodulation circuit for the fiber-optic gyroscope according to claim 1, wherein: and the test tool circuit is also provided with an external outgoing line and a connector which are used for being connected with the industrial personal computer and an external power supply.
3. A method for improving the debugging efficiency of a digital demodulation circuit for a fiber-optic gyroscope is characterized in that the device for improving the debugging efficiency of the digital demodulation circuit for the fiber-optic gyroscope, which is disclosed by the claim 1 or 2, is adopted, and the specific implementation steps are as follows:
step 1: installing a digital demodulation circuit to be tested on a test tool circuit, realizing signal connection between the digital demodulation circuit to be tested and the test tool circuit through a spring probe, and respectively connecting the digital demodulation circuit to be tested with an industrial personal computer and an external power supply;
step 2: generating a first sinusoidal signal through an FPGA control module of a digital demodulation circuit to be tested, outputting the initial sinusoidal signal from a feedback driving module after passing through a D/A conversion module of the digital demodulation circuit to be tested, enabling the output signal to enter a front amplifier/filter module of the digital demodulation circuit to be tested through a spring probe of a test tool circuit, then entering an A/D conversion module, and finally returning to an RAM of the FPGA control module for storage;
and step 3: the FPGA control module receives instruction information sent by a program of an upper computer in the industrial personal computer, signals stored in the RAM are sent to the industrial personal computer through the serial port module, the industrial personal computer draws and displays a second sinusoidal signal, and whether corresponding change is generated or not in comparison with the first sinusoidal signal by judging the amplitude of the second sinusoidal signal, so that closed-loop debugging of the digital demodulation circuit to be tested is realized.
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