Inertial device scale factor self-identification method and device based on double-frame inertial measurement unit

Abstract

The invention provides an inertial device scale factor self-identification method and device based on a double-frame inertial measurement unit, and solves the technical problems that the existing scale factor calibration environment is complicated, and the calibration process is time-consuming. The method comprises the following steps: setting an initialization environment calibrated by a double-frame inertial measurement unit; controlling the inertial measurement unit to form an orderly rotating and static continuous transposition process according to the transposition sequence; accumulative sum data of original pulse numbers output by the corresponding gyroscope and the accelerometer in the transposition process are collected, and a gyroscope scale factor and an accelerometer scale factor are formed according to the accumulative sum data; and unloading the calibration data to a parameter storage area of the double-frame inertial measurement unit, then powering off the inertial measurement unit, and ending the calibration. The method has the advantages of short calibration time, few guarantee requirements, simple and quick operation and the like. The method can be compatible with a slip-ring-free double-frame inertial measurement unit with a limiting mechanism, can also be suitable for a three-frame inertial measurement unit, and has higher universality.

Description

Technical Field

[0001] The present invention relates to the technical field of inertial group calibration, and in particular to a method and device for self-identifying a scale factor of an inertial device based on a dual-frame inertial group. Background Art

[0002] In the prior art, after the dual-frame inertial unit is assembled, the information output by the gyroscope and accelerometer is the original number of pulses, which needs to be converted by the scale factor to obtain the angular increment and velocity increment information used for navigation solution. Due to the heterogeneous configuration of the gyroscope, there are many differences between the model specifications of the accelerometer, and the channels of the IF processing circuit, resulting in that the scale factors of the gyroscope and accelerometer are often different, and they need to be accurately obtained through prior calibration. Usually, the parameter calibration of the inertial measurement unit (IMU) can be achieved through the multi-position tumbling of the six-degree-of-freedom turntable, but this method has the disadvantages of cumbersome installation, many accompanying test equipment, and long calibration time. Summary of the invention

[0003] In view of the above problems, an embodiment of the present invention provides a method and apparatus for self-identification of scale factors of an inertial device based on a dual-frame inertial group, which solves the technical problems of complex calibration environment and time-consuming calibration process of existing scale factors.

[0004] The inertial device scale factor self-identification method based on the dual-frame inertial group according to an embodiment of the present invention includes:

[0005] Set up the initialization environment for dual-frame inertial group calibration;

[0006] Control the inertial measurement unit to form a continuous rotation and stationary process in an orderly manner according to the rotation sequence;

[0007] Collecting the accumulated data of the original pulse numbers output by the corresponding gyroscope and accelerometer during the transposition process, and forming the gyroscope scale factor and the accelerometer scale factor according to the accumulated data;

[0008] After the calibration data is transferred to the parameter storage area of ​​the dual-frame inertial group, the inertial group is powered off and the calibration is completed.

[0009] In one embodiment of the present invention, the initialization environment setting includes:

[0010] Place the double-frame inertial group on a stable table, with the plumb axis of the inertial group pointing basically to the sky, and the horizontal axis pointing to no special requirements;

[0011] Connect the power supply cable, communication cable, and power on the host controller;

[0012] The dual-frame inertial group is powered on;

[0013] When the inner and outer frames are at zero position, the x, y, and z sensitive axes of the inertia group point to the right, front, and up.

[0014] In one embodiment of the present invention, the transposition sequence includes:

[0015]

[0016] In one embodiment of the present invention, during the continuous indexing process, each indexing time is 10 seconds, the static time is 10 seconds, and the indexing angular velocity is 50° / s.

[0017] In one embodiment of the present invention, the accumulated data includes the accumulated sum of the positive input raw pulses of the x, y, and z gyroscopes, respectively. The accumulated sum of the negative input raw pulses of the x, y, and z gyroscopes are The accumulated sum of the positive input raw pulses of the x, y, and z accelerometers are The sum of the negative input raw pulses of the x, y, and z accelerometers is

[0018] In one embodiment of the present invention, the gyroscope scale factor is formed by the following calculation method:

[0019]

[0020] in, K g(m) is the gyro scale factor, including the x gyro scale factor K gx , y gyro scale factor K gy , z gyro scale factor K gz , the unit of gyroscope scale factor is: rad / pulse.

[0021] In one embodiment of the present invention, the accelerometer scale factor is formed by the following calculation method:

[0022]

[0023] Where g0 is the local gravitational acceleration, Δt a Take 10s, K a(m) is the scale factor of the accelerometer, including the x accelerometer scale factor K ax ,y accelerometer scale factor K ay , z accelerometer scale factor K az , the accelerometer scale factor unit is: m / s / pulse.

[0024] In one embodiment of the present invention, transferring the calibration data includes:

[0025] Each scale factor is formatted in a standard format and then transferred to the parameter storage area of ​​the inertia group.

[0026] The inertial device scale factor self-identification device based on the dual-frame inertial group according to an embodiment of the present invention comprises:

[0027] A memory for storing program codes in a process of processing the method for self-identification of the scale factor of an inertial device based on a dual-frame inertial group according to any one of claims 1 to 8;

[0028] A processor is used to execute the program code.

[0029] The inertial device scale factor self-identification device based on the dual-frame inertial group according to an embodiment of the present invention comprises:

[0030] Initialization module, used to set the initialization environment for dual-frame inertial group calibration;

[0031] An action execution module is used to control the inertial measurement unit to form a continuous rotation process of orderly rotation and stillness according to the rotation sequence;

[0032] A data forming module, used for collecting the accumulated data of the original pulse numbers outputted by the corresponding gyroscope and accelerometer during the transposition process, and forming the gyroscope scale factor and the accelerometer scale factor according to the accumulated data;

[0033] The data transfer and storage module is used to transfer the calibration data to the parameter storage area of ​​the dual-frame inertial group, after which the inertial group is powered off and the calibration is completed.

[0034] The present invention proposes a method for rapid self-identification of the scale factor of inertial devices based on a dual-frame inertial group. The rotating frame inside the dual-frame inertial group is used to replace the function of the six-degree-of-freedom turntable, and a multi-position transposition sequence is designed, which can complete the rapid self-identification of the scale factor of the gyroscope and accelerometer within 3 minutes. The method does not require the addition of any external equipment and can be completed with one key by sending instructions from the host computer. After the calibration is completed, the scale factor of the gyroscope and accelerometer can be directly written into the inertial group, which is convenient for subsequent inertial group performance testing and other work. It has the advantages of short calibration time, less guarantee requirements, simple and fast operation, etc. The method is compatible with a slip-ring-free dual-frame inertial group with a limit mechanism, and can also be applied to a three-frame inertial group, with stronger versatility. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 FIG. 1 is a schematic diagram of the assembly of a dual-frame inertial group in an inertial device scale factor self-identification method based on a dual-frame inertial group according to an embodiment of the present invention.

[0036] Figure 2 FIG. 1 is a flow chart of a method for self-identification of scale factors of an inertial device based on a dual-frame inertial group according to an embodiment of the present invention.

[0037] Figure 3 FIG. 1 is a schematic diagram of the architecture of an inertial device scale factor self-identification device based on a dual-frame inertial group according to an embodiment of the present invention. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solution and advantages of the present invention clearer and more understandable, the present invention is further described below in conjunction with the accompanying drawings and specific implementation methods. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] In one embodiment of the present invention, a method for self-identification of inertial device scale factor based on a dual-frame inertial group is used. Figure 1 As shown. Figure 1 In the dual-frame inertial group, the outer frame for forming the roll measurement and the inner frame for forming the heading measurement are fixed in the inner frame at an angle matching the roll axis. The inertial measurement unit (IMU) includes an accelerometer and a gyroscope. The dual-frame inertial group is fixed by a fixed structure and forms a transmission line for the electric power signal and a communication line for the host computer control signal.

[0040] An embodiment of the present invention is based on a dual-frame inertial device scale factor self-identification method. Figure 2 As shown. Figure 2 In this embodiment, the present invention includes:

[0041] Step 100: Set the initialization environment for dual-frame inertial group calibration.

[0042] The calibration initialization environment includes but is not limited to the fixed environment of the dual-frame inertial system, the power supply environment, the communication environment, and the initial orientation of the accelerometer and the gyroscope.

[0043] In one embodiment of the present invention, initializing the environment settings includes:

[0044] Place the double-frame inertial group on a stable table, with the plumb axis of the inertial group pointing basically to the sky, and the horizontal axis pointing to no special requirements;

[0045] Connect the power supply cable, communication cable, and power on the host controller;

[0046] The dual-frame inertial group is powered on;

[0047] When the inner and outer frames are at zero position, the x, y, and z sensitive axes of the inertia group point to the right, front, and up.

[0048] Step 200: Control the inertial measurement unit to form a continuous indexing process of orderly rotation and stillness according to the indexing sequence.

[0049] In one embodiment of the present invention, each indexing time is set to 10 seconds, the resting time is set to 10 seconds, and the indexing angular velocity is set to 50° / s.

[0050] In one embodiment of the present invention, the indexing order is set as follows:

[0051]

[0052]

[0053] Step 300: Collect the accumulated data of the original pulse numbers output by the corresponding gyroscope and accelerometer during the indexing process, and form the gyroscope scale factor and the accelerometer scale factor according to the accumulated data.

[0054] During the rotation (and stop) process, the cumulative sum of the raw pulses of the corresponding gyroscopes and accelerometers is collected. The cumulative sum of the positive input raw pulses of the x, y, and z gyroscopes is The accumulated sum of the negative input raw pulses of the x, y, and z gyroscopes are The accumulated sum of the positive input raw pulses of the x, y, and z accelerometers are The sum of the negative input raw pulses of the x, y, and z accelerometers is

[0055] The gyroscope scale factor is formed by the following calculation:

[0056]

[0057] in, K g(m) is the gyro scale factor, including the x gyro scale factor K gx , y gyro scale factor K gy , z gyro scale factor K gz , the unit of gyroscope scale factor is: rad / pulse.

[0058] The accelerometer scale factor is formed by the following calculation:

[0059]

[0060] Where g0 is the local gravitational acceleration, Δ a Take 10s, K a(m) is the scale factor of the accelerometer, including the x accelerometer scale factor K ax ,y accelerometer scale factor K ay , z accelerometer scale factor K az , the accelerometer scale factor unit is: m / s / pulse.

[0061] Step 400: After transferring the calibration data to the parameter storage area of ​​the dual-frame inertial group, the inertial group is powered off to end the calibration.

[0062] The scale factor is formatted in a standard format and then transferred to the parameter storage area of ​​the inertial group for data call in subsequent inertial group applications.

[0063] The self-identification method of the scale factor of the inertial device based on the dual-frame inertial group of the embodiment of the present invention can complete the rapid self-identification of the scale factors of the gyroscope and accelerometer within 3 minutes by designing a reasonable transposition order and calibration algorithm, and the calibration accuracy is better than 100ppm. The method does not require the addition of any external equipment and can be completed with one click by sending instructions from the host computer. After the calibration is completed, the scale factors of the gyroscope and accelerometer can be directly written into the inertial group, which is convenient for subsequent inertial group performance testing and other work. It has the advantages of short calibration time, less guarantee requirements, simple and fast operation, etc. The method is compatible with the slip ring-free dual-frame inertial group with a limit mechanism, and can also be applied to the three-frame inertial group, and has universality.

[0064] An inertial device scale factor self-identification device based on a dual-frame inertial group, comprising:

[0065] A memory, used to store program codes in the process of processing the self-identification method of the inertial device scale factor based on the dual-frame inertial group in the above embodiment;

[0066] The processor is used to execute the program code in the process of the self-identification method of the inertial device scale factor based on the dual-frame inertial group in the above embodiment.

[0067] The processor may be a DSP (Digital Signal Processor) digital signal processor, an FPGA (Field-Programmable Gate Array) field programmable gate array, an MCU (Microcontroller Unit) system board, a SoC (system on a chip) system board, or a PLC (Programmable Logic Controller) minimum system including I / O.

[0068] An embodiment of the present invention is based on a dual-frame inertial device scale factor self-identification device. Figure 3 As shown. Figure 3 In this embodiment, the present invention includes:

[0069] Initialization module 10, used to set the initialization environment of dual-frame inertial group calibration;

[0070] The action execution module 20 is used to control the inertial measurement unit to form a continuous rotation process of orderly rotation and stillness according to the rotation sequence;

[0071] The data forming module 30 is used to collect the accumulated data of the original pulse numbers output by the corresponding gyroscope and accelerometer during the transposition process, and form the gyroscope scale factor and the accelerometer scale factor according to the accumulated data;

[0072] The data transfer and storage module 40 is used to transfer the calibration data to the parameter storage area of ​​the dual-frame inertial group and then cut off the power of the inertial group to end the calibration.

[0073] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A method for self-identification of inertial device scale factor based on dual-frame inertial group, characterized in that: include: Set up the initialization environment for dual-frame inertial group calibration; Control the inertial measurement unit to form a continuous rotation and stationary process in an orderly manner according to the rotation sequence; Collecting the accumulated data of the original pulse numbers output by the corresponding gyroscope and accelerometer during the transposition process, and forming the gyroscope scale factor and the accelerometer scale factor according to the accumulated data; After the calibration data is transferred to the parameter storage area of ​​the dual-frame inertial group, the inertial group is powered off and the calibration is completed.

2. The method for self-identification of inertial device scale factor based on dual-frame inertial group according to claim 1, characterized in that: The initialization environment setting includes: Place the double-frame inertial group on a stable table, with the plumb axis of the inertial group pointing basically to the sky, and the horizontal axis pointing to no special requirements; Connect the power supply cable, communication cable, and power on the host controller; The dual-frame inertial group is powered on; When the inner and outer frames are at zero position, the x, y, and z sensitive axes of the inertia group point to the right, front, and up.

3. The method for self-identification of inertial device scale factor based on dual-frame inertial group according to claim 1, characterized in that: The transposition sequence includes:

4. The method for self-identification of inertial device scale factor based on dual-frame inertial group according to claim 1, characterized in that: During the continuous indexing process, each indexing time is 10 seconds, the rest time is 10 seconds, and the indexing angular velocity is 50° / s.

5. The method for self-identification of inertial device scale factor based on dual-frame inertial group according to claim 1, characterized in that: The accumulated data includes the accumulated sum of the positive input raw pulses of the x, y, and z gyroscopes, respectively. The accumulated sum of the negative input raw pulses of the x, y, and z gyroscopes are The accumulated sum of the positive input raw pulses of the x, y, and z accelerometers are The sum of the negative input raw pulses of the x, y, and z accelerometers is 6. The method for self-identification of inertial device scale factor based on dual-frame inertial group according to claim 1, characterized in that: The gyroscope scale factor is formed by the following calculation method: in, K g(m) is the gyro scale factor, including the x gyro scale factor K gx , y gyro scale factor K gy , z gyro scale factor K gz , the unit of gyroscope scale factor is: rad / pulse.

7. The method for self-identification of inertial device scale factor based on dual-frame inertial group according to claim 1, characterized in that: The accelerometer scale factor is formed by the following calculation method: Where g0 is the local gravitational acceleration, Δt a Take 10s, K a(m) is the scale factor of the accelerometer, including the x accelerometer scale factor K ax ,y accelerometer scale factor k ay , z accelerometer scale factor k az , the accelerometer scale factor unit is: m / s / pulse.

8. The method for self-identification of inertial device scale factor based on dual-frame inertial group according to claim 1, characterized in that: The transferring of the calibration data comprises: Each scale factor is formatted in a standard format and then transferred to the parameter storage area of ​​the inertia group.

9. A self-identification device for inertial device scale factor based on a dual-frame inertial group, characterized in that: include: A memory for storing program codes in a process of processing the method for self-identification of the scale factor of an inertial device based on a dual-frame inertial group according to any one of claims 1 to 8; A processor is used to execute the program code.

10. An inertial device scale factor self-identification device based on a dual-frame inertial group, characterized in that: include: Initialization module, used to set the initialization environment for dual-frame inertial group calibration; An action execution module is used to control the inertial measurement unit to form a continuous rotation process of orderly rotation and stillness according to the rotation sequence; A data forming module, used for collecting the accumulated data of the original pulse numbers outputted by the corresponding gyroscope and accelerometer during the transposition process, and forming the gyroscope scale factor and the accelerometer scale factor according to the accumulated data; The data transfer and storage module is used to transfer the calibration data to the parameter storage area of ​​the dual-frame inertial group, after which the inertial group is powered off and the calibration is completed.

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