Multifunctional precise calibration clamp system for pedestrian inertial navigation product

Abstract

The invention discloses a multifunctional precise calibration clamp system for pedestrian inertial navigation products, and belongs to the technical field of inertial navigation and positioning. The system comprises an upper computer module and lower computer hardware, the upper computer module collects and processes hardware data of the lower computer, and displays and sends a calibration instruction to a user through a man-machine test interface; the lower computer hardware receives a calibration instruction to calibrate the pedestrian inertial navigation product, a motion control card, a servo controller and the like included in the lower computer hardware work cooperatively, and an optical encoder monitors a servo motor in real time to guarantee accurate motion; the system achieves automatic calibration, solves the problem that traditional manual calibration is tedious and the like, has the advantages of being efficient, accurate, easy and convenient to operate, high in adaptability and stable, effectively improves calibration efficiency and product quality, and reduces labor and operation cost.

Description

Technical Field

[0001] The present invention relates to the technical field of inertial navigation and positioning, and specifically to a precision calibration fixture system for a multi-functional pedestrian inertial navigation product. Background Art

[0002] With the continuous development of inertial navigation and positioning technologies, pedestrian inertial navigation products with multi-sensor fusion have gradually become the mainstream in the market. Such products integrate multiple sensors, such as accelerometers, gyroscopes, magnetometers, etc., to provide more accurate and reliable navigation and positioning information. The multi-sensor fusion technology can utilize the complementarity of different sensors to improve the robustness and accuracy of the system, thus showing great application potential in fields such as pedestrian navigation and indoor positioning.

[0003] However, the existing technologies still have the following defects and deficiencies: Manual calibration is cumbersome. Traditional pedestrian inertial navigation devices require multiple manual calibrations, which are complex and time-consuming processes, and have high requirements for the professional skills of operators; The degree of automation is low. There is a lack of automatic reset and calibration initialization functions, and necessary steps cannot be automatically completed during the calibration process, increasing the risk of errors; The accuracy and stability are insufficient. Due to the limitations of calibration technologies, the accuracy and stability of the devices are difficult to meet the requirements of high-precision applications and are easily affected by environmental factors; The operation is complex and requires professional production and inspection personnel to operate, increasing labor costs and training costs; There is a lack of real-time device status monitoring, and the status information of the device cannot be obtained in a timely manner, and the calibration process cannot be immediately started when the device reaches the calibration threshold. Summary of the Invention

[0004] The purpose of the present invention is to provide a precision calibration fixture system for a multi-functional pedestrian inertial navigation product to solve the problems raised in the existing technologies.

[0005] To achieve the above purpose, the present invention provides the following technical solution: A precision calibration fixture system for a multi-functional pedestrian inertial navigation product, the system includes a host computer module, a motion control card, a pressure detection module, a first fixture module, and a second fixture module;

[0006] The host computer module is used to collect data from the pedestrian inertial navigation product and display it to the user through a human-machine test interface, and process the collected data and send calibration instructions to the motion control card;

[0007] The motion control card receives the calibration instructions sent by the host computer module, controls the first fixture module and the second fixture module to complete the calibration instructions sent by the host computer module by sending pulse signals, receives the calibration data fed back by the first fixture module and the second fixture module, and transmits the calibration data to the host computer module;

[0008] The air pressure detection module is used to detect the maximum and minimum values of the air pressure and determine whether the air pressure difference is less than the air pressure threshold;

[0009] The motion control card is electrically connected to the host computer module, the air pressure detection module is electrically connected to the host computer module, and the first fixture module and the second fixture module are respectively electrically connected to the motion control card.

[0010] Further, the first fixture module includes a servo controller, a servo motor, a coupling, a connecting rod, an optical encoder, a fixture, a magnetometer, and a gyroscope;

[0011] The first fixture module is used to calibrate the magnetometer and the gyroscope;

[0012] The servo controller receives the pulse signal sent by the motion control card and converts the pulse signal into a drive signal for driving the servo motor to rotate; the servo motor rotates according to the drive signal and drives the fixture to complete the calibration instruction issued by the host computer module through the coupling and the connecting rod; the fixture is used to fix the magnetometer and the gyroscope; the optical encoder is used to monitor the calibration data in real time and feed back the calibration data to the motion control card;

[0013] The above servo controller acts as a bridge connecting the motion control card and the servo motor. The servo controller receives the control signal sent by the motion control card, further converts it into a form suitable for driving the servo motor, and can also monitor and feedback-adjust the operating state of the servo motor to ensure the stable operation of the servo motor; the servo motor, as a power output device, rotates according to the drive signal transmitted by the servo controller, provides mechanical power for the entire system, and drives the fixture to achieve various position and angle adjustments to meet the calibration requirements of pedestrian inertial navigation products;

[0014] The two components of the coupling and the connecting rod are mainly used to connect the servo motor and the fixture, transmit the rotational motion of the servo motor to the fixture, and ensure the smoothness and accuracy of the motion during the transmission, so that the fixture can move precisely according to the predetermined requirements;

[0015] The optical encoder is used to monitor the motion state of the servo motor. It is connected to the servo controller and can obtain information such as the rotation angle and speed of the servo motor in real time and feed back this information to the host computer module;

[0016] Through this feedback mechanism, the host computer module can accurately understand the actual motion conditions of the lower computer, so as to adjust the control instructions in a timely manner and improve the control accuracy and stability of the system;

[0017] The fixture is a component that directly contacts the pedestrian inertial navigation product. Its design adopts a modular structure, which can adapt to pedestrian inertial navigation products of different models and specifications. During the operation of the system, the fixture is responsible for fixing the pedestrian inertial navigation product to keep it in a stable position and angle during the testing and calibration processes, ensuring the accuracy of the calibration operation.

[0018] Furthermore, the calibration process of the first fixture module for the magnetometer and gyroscope includes:

[0019] Step 1-1: The host computer module issues a start calibration instruction to the motion control card;

[0020] Step 1-2: The motion control card receives the start calibration instruction and sends the start calibration instruction to the servo controller. The servo controller reads the magnetic angle value between the zero point of the servo motor and the magnetic north of the magnetometer according to the start calibration instruction and uploads the magnetic angle value to the host computer module;

[0021] Step 1-3: The host computer module judges the magnetic angle value and adjusts the position of the servo motor according to the judgment result;

[0022] Step 1-4: Adjust the initial angle of the servo motor according to a preset angle. The host computer module stores the initial angle and controls the rotation of the servo motor according to a preset rotation speed and a preset number of turns. The optical encoder real-time monitors the actual angle of the magnetometer when the servo motor completes the preset number of turns according to the preset rotation speed;

[0023] The preset rotation speed in the above steps is used for the control of the angle change during the subsequent magnetometer test, providing a stable rotation speed basis for the whole test, ensuring the consistency of the test, and obtaining more comprehensive and accurate magnetic field data through the preset number of turns, so as to calibrate the magnetometer and reduce errors;

[0024] Step 1-5: Calibrate the magnetometer and the gyroscope according to the initial angle and the actual angle;

[0025] The calibration standard of the magnetometer is that the error between the initial angle of the servo motor and the actual angle of the magnetometer is less than the first calibration threshold, and the difference between the maximum value and the minimum value of the error is less than the second calibration threshold;

[0026] In the above steps, the first calibration threshold is set to ensure that the magnetometer can read the angle more accurately and the error range is within the acceptable limit; the second calibration threshold is set to ensure the accuracy stability of the magnetometer during the whole rotation process and avoid excessive fluctuations;

[0027] The calibration standard of the gyroscope is that the error between the average value of the actual angle of the magnetometer and the first preset angle threshold is less than the gyroscope calibration threshold;

[0028] The above calibration of the gyroscope is to test the accuracy of the gyroscope associated with the magnetometer and ensure the accuracy of angle reading.

[0029] Further, the second fixture module includes a servo controller, a servo motor, a coupling, a connecting rod, an optical encoder, a fixture, an accelerometer, and a gyroscope;

[0030] The second fixture module is used to calibrate the accelerometer and the gyroscope.

[0031] Further, the calibration process of the second fixture module for the accelerometer and the gyroscope includes:

[0032] Step 2-1: The host computer module issues a start calibration instruction to the motion control card;

[0033] Step 2-2: The motion control card receives the start calibration instruction and sends the start calibration instruction to the servo controller. The servo controller reads the initial angle of the servo motor according to the start calibration instruction and uploads the initial angle to the host computer module;

[0034] Step 2-3: The host computer module judges the initial angle of the servo motor and adjusts the initial angle of the servo motor according to the judgment result;

[0035] Step 2-4: The servo motor rotates at a preset speed and angle threshold. When the servo motor rotates to the preset target angle according to the angle threshold, the host computer module issues a target angle completion instruction and reads the actual angle of the accelerometer monitored by the optical encoder;

[0036] Step 2-5: Calibrate the accelerometer and the gyroscope according to the target angle and the actual angle;

[0037] The calibration standard of the accelerometer is that the error between the target angle of the servo motor and the actual angle of the accelerometer is less than the first calibration threshold, and the difference between the maximum value and the minimum value of the error is less than the second calibration threshold;

[0038] The calibration standard of the gyroscope is that the error between the average value of the actual angle and the second preset angle threshold is less than the gyroscope calibration threshold.

[0039] The above steps are to test the accuracy of the gyroscope associated with the accelerometer and ensure the accuracy of angle reading.

[0040] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0041] 1. High-efficiency and precise calibration

[0042] The host computer module can collect and process data from the lower computer hardware and send operation instructions. Combined with a high-precision motion control card, servo controller, servo motor, and optical encoder, it realizes the automatic calibration of multiple angles of the pedestrian inertial navigation product, greatly improving the accuracy and efficiency of calibration.

[0043] 2. Simple and easy to operate

[0044] The operation process has been greatly simplified, eliminating the need for professional technical personnel to operate, reducing labor and training costs. The human-machine test interface provided by the host computer is intuitive and clear. Operators can easily control the entire calibration process by simply operating the buttons on the interface, improving work efficiency and reducing the risk of errors caused by complex operations.

[0045] 3. Strong adaptability and stability

[0046] The modular design of the fixture enables it to quickly adapt to different models and specifications of pedestrian inertial navigation products, meeting diverse production monitoring requirements. At the same time, the system adopts non-magnetic materials and a surrounding wrapping design, effectively reducing external interference. In addition, the magnetic angle calibration function of the calibration platform, using advanced magnetic detection technology and magnetic sensor technology, further improves the stability and reliability of calibration, ensuring accurate calibration results in different environments and enhancing the overall quality of the product. Brief Description of the Drawings

[0047] Figure 1 It is a schematic diagram of the system structure of a precision calibration fixture system for a multifunctional pedestrian inertial navigation product of the present invention;

[0048] Figure 2 It is a schematic diagram of the calibration process of the magnetometer and gyroscope of a precision calibration fixture system for a multifunctional pedestrian inertial navigation product of the present invention;

[0049] Figure 3 It is a schematic diagram of the calibration process of the accelerometer and gyroscope of a precision calibration fixture system for a multifunctional pedestrian inertial navigation product of the present invention;

[0050] Figure 4 It is a schematic diagram of the air pressure detection process of a precision calibration fixture system for a multifunctional pedestrian inertial navigation product of the present invention. Detailed Embodiments

[0051] Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of the present invention.

[0052] Embodiment: As Figures 1 - 4 shown, the present invention provides a technical solution, a precision calibration fixture system for a multifunctional pedestrian inertial navigation product. The system includes a host computer module, a motion control card, a barometric pressure detection module, a first fixture module, and a second fixture module;

[0053] The host computer module is used to collect data of the pedestrian inertial navigation product and display it to the user through a human-machine test interface, and process the collected data and send a calibration instruction to the motion control card;

[0054] The motion control card receives the calibration instruction sent by the host computer module, controls the first fixture module and the second fixture module to complete the calibration instruction sent by the host computer module by sending pulse signals, receives the calibration data fed back by the first fixture module and the second fixture module, and transmits the calibration data to the host computer module;

[0055] The barometric pressure detection module is used to detect the maximum and minimum values of the barometric pressure, and judge whether the barometric pressure difference is less than the barometric pressure threshold. The judgment process is as Figure 4 shown;

[0056] The motion control card is electrically connected to the host computer module, the barometric pressure detection module is electrically connected to the host computer module, and the first fixture module and the second fixture module are respectively electrically connected to the motion control card;

[0057] Among them, the first fixture module includes a servo controller, a servo motor, a coupling, a connecting rod, an optical encoder, a fixture, a magnetometer, and a gyroscope;

[0058] The first fixture module is used to calibrate the magnetometer and the gyroscope;

[0059] The servo controller receives the pulse signal sent by the motion control card and converts the pulse signal into a driving signal for driving the servo motor to rotate; the servo motor rotates according to the driving signal, and drives the fixture to complete the calibration instruction issued by the host computer module through the coupling and the connecting rod; the fixture is used to fix the magnetometer and the gyroscope; the optical encoder is used to monitor the calibration data in real time and feed back the calibration data to the motion control card;

[0060] Refer to Figure 2 , among which, the calibration process of the first fixture module for the magnetometer and the gyroscope includes:

[0061] Step 1-1: The host computer module issues a start calibration instruction to the motion control card;

[0062] Step 1-2: The motion control card receives the start calibration instruction and sends the start calibration instruction to the servo controller. The servo controller reads the magnetic angle value between the zero point of the servo motor and the magnetic north of the magnetometer according to the start calibration instruction, and uploads the magnetic angle value to the host computer module;

[0063] Step 1-3: The host computer module judges the magnetic angle value and adjusts the position of the servo motor according to the judgment result;

[0064] In the above steps, the judgment of the magnetic angle value is to ensure that the zero point of the motor is aligned with the magnetic north;

[0065] Step 1-4: Adjust the initial angle of the servo motor according to a preset angle. The host computer module stores the initial angle and controls the rotation of the servo motor according to a preset speed and a preset number of turns. The optical encoder monitors the actual angle of the magnetometer in real time when the servo motor completes the preset number of turns according to the preset speed;

[0066] Step 1-5: Calibrate the magnetometer and the gyroscope according to the initial angle and the actual angle;

[0067] The calibration standard of the magnetometer is that the error between the initial angle of the servo motor and the actual angle of the magnetometer is less than the first calibration threshold, and the difference between the maximum value and the minimum value of the error is less than the second calibration threshold;

[0068] The calibration standard of the gyroscope is that the error between the average value of the actual angles of the magnetometer and the first preset angle threshold is less than the gyroscope calibration threshold;

[0069] In the embodiment of the present invention, the relevant test processes of the magnetometer and the gyroscope include: Magnetometer test standard 1, set the number of turns and the initial angle of the servo motor to rotate, and then read the actual angle of the magnetometer at the test point, and compare the difference between these two angles with the threshold value to test the magnetometer; Magnetometer test standard 2, during the rotation of the motor, a series of error values will be obtained, find the maximum error value and the minimum error value among them, and based on the maximum error value and the minimum error value, combine the threshold value to test the magnetometer; Gyroscope test standard, read the average value of the actual angles of the magnetometer, and combine the threshold value to test the gyroscope;

[0070] Refer to Figure 3 , in which, the calibration process of the accelerometer and the gyroscope by the second fixture module includes:

[0071] Step 2-1: The host computer module issues a start calibration instruction to the motion control card;

[0072] Step 2-2: The motion control card receives the start calibration instruction and sends the start calibration instruction to the servo controller. The servo controller reads the initial angle of the servo motor according to the start calibration instruction and uploads the initial angle to the host computer module;

[0073] Step 2-3: The host computer module judges the initial angle of the servo motor and adjusts the initial angle of the servo motor according to the judgment result;

[0074] In the above steps, judging the initial angle of the servo motor is also to ensure that the zero point of the servo motor is aligned with magnetic north;

[0075] Step 2-4: The servo motor rotates at a preset speed and angle threshold. When the servo motor rotates to the preset target angle according to the angle threshold, the host computer module issues a target angle completion instruction and reads the actual angle of the accelerometer monitored by the optical encoder;

[0076] Step 2-5: Calibrate the accelerometer and gyroscope according to the target angle and the actual angle;

[0077] The calibration standard of the accelerometer is that the error between the target angle of the servo motor and the actual angle of the accelerometer is less than the first calibration threshold, and the difference between the maximum value and the minimum value of the error is less than the second calibration threshold;

[0078] The calibration standard of the gyroscope is that the error between the average value of the actual angles and the second preset angle threshold is less than the gyroscope calibration threshold;

[0079] In the embodiment of the present invention, the relevant test processes of the accelerometer and the gyroscope include: setting the rotation speed and target angle of the servo motor, then reading the actual angle of the accelerometer at the test point and testing each axis; Accelerometer test standard one, judging the maximum value and the minimum value measured by the accelerometer, calculating the difference between the target angle and the actual angle, and comparing the difference with the threshold value to test the accelerometer; Accelerometer test standard two, during the rotation of the motor, a series of error values will be obtained, find the maximum error and the minimum error among them, and based on the maximum error and the minimum error, test the accelerometer; Gyroscope test standard, reading the average value of the actual angles of the accelerometer and testing the gyroscope in combination with the threshold value.

[0080] Finally, it should be noted that the above are only preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A multifunctional precision calibration fixture system for pedestrian inertial navigation products, characterized by: The system includes a host computer module, a motion control card, an air pressure detection module, a first fixture module and a second fixture module; The host computer module is used to collect data from the pedestrian inertial navigation product and display it to the user through the human-machine test interface, and to process the collected data and send calibration instructions to the motion control card; The motion control card receives the calibration instruction sent by the host computer module, controls the first fixture module and the second fixture module to complete the calibration instruction sent by the host computer module by sending a pulse signal, receives the calibration data fed back by the first fixture module and the second fixture module, and transmits the calibration data to the host computer module; The air pressure detection module is used to detect the maximum and minimum values ​​of the air pressure and determine whether the air pressure difference is less than the air pressure threshold; The motion control card is electrically connected to the host computer module, the air pressure detection module is electrically connected to the host computer module, and the first fixture module and the second fixture module are electrically connected to the motion control card respectively.

2. According to claim 1, a multifunctional pedestrian inertial navigation product precision calibration fixture system is characterized by: The first fixture module includes a servo controller, a servo motor, a coupling, a connecting rod, an optical encoder, a fixture, a magnetometer and a gyroscope; The first fixture module is used to calibrate the magnetometer and the gyroscope; The servo controller receives the pulse signal sent by the motion control card and converts the pulse signal into a drive signal for driving the servo motor to rotate; the servo motor rotates according to the drive signal, and drives the fixture through the coupling and the connecting rod to complete the calibration instructions issued by the upper computer module; the fixture is used to fix the magnetometer and gyroscope; the optical encoder is used to monitor the calibration data in real time and feed the calibration data back to the motion control card.

3. The multifunctional pedestrian inertial navigation product precision calibration fixture system according to claim 2, characterized in that: The calibration process of the magnetometer and the gyroscope by the first fixture module includes: Step 1-1: The host computer module issues a start calibration instruction to the motion control card; Step 1-2: The motion control card receives the start calibration instruction and sends the start calibration instruction to the servo controller. The servo controller reads the magnetic angle value between the servo motor zero point and the magnetic north of the magnetometer according to the start calibration instruction, and uploads the magnetic angle value to the host computer module; Step 1-3: The host computer module determines the magnetic angle value and adjusts the position of the servo motor according to the determination result; Step 1-4: adjusting the initial angle of the servo motor according to a preset angle, the host computer module storing the initial angle and controlling the rotation of the servo motor according to a preset speed and a preset number of turns, and the optical encoder monitoring in real time the actual angle of the magnetometer when the servo motor completes a preset number of turns according to the preset speed; Step 1-5: calibrating the magnetometer and the gyroscope according to the initial angle and the actual angle; The calibration standard of the magnetometer is that the error between the initial angle of the servo motor and the actual angle of the magnetometer is less than a first calibration threshold, and the difference between the maximum value and the minimum value of the error is less than a second calibration threshold; The calibration standard of the gyroscope is that the error between the average value of the actual angle of the magnetometer and the first preset angle threshold is less than the gyroscope calibration threshold.

4. The multifunctional pedestrian inertial navigation product precision calibration fixture system according to claim 2, characterized in that: The second fixture module includes a servo controller, a servo motor, a coupling, a connecting rod, an optical encoder, a fixture, an accelerometer and a gyroscope; The second fixture module is used to calibrate the accelerometer and the gyroscope.

5. The multifunctional pedestrian inertial navigation product precision calibration fixture system according to claim 4, characterized in that: The calibration process of the second fixture module for the accelerometer and the gyroscope includes: Step 2-1: The host computer module issues a start calibration instruction to the motion control card; Step 2-2: The motion control card receives the start calibration instruction, and sends the start calibration instruction to the servo controller, the servo controller reads the initial angle of the servo motor according to the start calibration instruction, and uploads the initial angle to the host computer module; Step 2-3: The host computer module determines the initial angle of the servo motor and adjusts the initial angle of the servo motor according to the determination result; Step 2-4: the servo motor rotates according to a preset speed and angle threshold. When the servo motor rotates to a preset target angle according to the angle threshold, the host computer module issues a target angle completion instruction and reads the actual angle of the accelerometer monitored by the optical encoder; Step 2-5: Calibrate the accelerometer and the gyroscope according to the target angle and the actual angle; The calibration standard of the accelerometer is that the error between the target angle of the servo motor and the actual angle of the accelerometer is less than a first calibration threshold, and the difference between the maximum value and the minimum value of the error is less than a second calibration threshold; The calibration standard of the gyroscope is that the error between the average value of the actual angle and the second preset angle threshold is less than the gyroscope calibration threshold.

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