Single-axis rotation modulation device for inertial navigation equipment based on time grating angle measurement

Abstract

The invention discloses a single-axis rotation modulation device for inertial navigation equipment based on time grating angle measurement. The device comprises a torque motor, a conductive slip ring, a time grating encoder, an angle measurement control circuit and a servo drive circuit, the torque motor drives the inertia measurement assembly to rotate; the conductive slip ring is used for realizing signal transmission; the time grating encoder is used for measuring the rotation angle of the inertia measurement assembly driven by the single-shaft rotation modulation device; the angle measurement control circuit is used for realizing time grating encoder angle signal decoding, realizing a control algorithm, performing control logic closed loop through an angle value, and outputting a torque motor rotation control signal; the servo drive circuit drives the torque motor to rotate; according to a rotation strategy, the single-axis rotation modulation device is controlled through PID three-closed-loop servo to drive the inertial measurement assembly to rotate periodically, and errors accumulated along with time of the inertial measurement assembly are modulated. The device is simple in structure installation and decoding mode, high in measurement precision and good in anti-interference performance.

Description

Technical Field

[0001] The invention belongs to the technical field of inertial navigation, and particularly relates to a single-axis rotation modulation device for an inertial navigation device based on time grating angle measurement. Background Art

[0002] To ensure the navigation safety of ships / submarines and the combat requirements of weapon systems, it is necessary to use inertial navigation devices to provide navigation information such as the position, speed, heading, attitude, and attitude angular velocity of the carrier. In inertial navigation devices, laser gyroscopes and accelerometers are used as inertial sensitive devices to measure three-dimensional space angular velocity and linear acceleration information. By integrating the three-dimensional space angular velocity and linear acceleration, navigation information such as the position, speed, heading, attitude, and attitude angular velocity in three-dimensional space is obtained. Due to the zero-bias errors of laser gyroscopes and accelerometers, the integration operation system will introduce the cumulative amount generated by the integration of zero-bias errors over time, resulting in the divergence of the navigation accuracy of inertial navigation devices over time. By adopting the rotation modulation technology to control the inertial measurement unit to drive the inertial sensitive devices to perform periodic flipping, the drift errors of the inertial devices can be modulated and canceled, effectively reducing the equivalent errors of gyroscopes and accelerometers in the navigation coordinate system and improving the accuracy of inertial navigation devices.

[0003] In current single-axis rotation modulation devices, the rotation angle measurement part uses sensor devices such as resolvers or circular grating encoders, and the angle measurement and control circuit is designed with DSP+FPGA / CPLD as the main processor. In the implementation process, it is found that there are at least the following deficiencies: The resolver measures the rotation angle with relatively low measurement accuracy, not exceeding 5 arcseconds at most, generally 10 arcseconds, and at the same time, the installation is complex, the power supply requirements are high, there are many lines, and it is easy to introduce interference, resulting in relatively large measurement errors. When the circular grating encoder measures the rotation angle, it is easily affected by oil stains, water vapor, etc., causing abnormal angle measurement or inability to work properly. Moreover, the traditional angle measurement and control circuit generally uses DSP+FPGA / CPLD, which is relatively high in development cost and power consumption. Summary of the Invention

[0004] The purpose of the invention is to provide a single-axis rotation modulation device for an inertial navigation device based on time grating angle measurement, which can further improve the control accuracy while reducing the cost and power consumption of the device, increasing the reliability, and driving the inertial measurement unit to perform periodic rotation according to a certain rule through the single-axis rotation modulation device to cancel the constant errors of inertial sensors, thereby improving the navigation accuracy of inertial navigation devices.

[0005] To solve the above technical problems, the technical solution adopted by the invention is as follows:

[0006] In a first aspect, the present invention provides a single-axis rotation modulation device for an inertial navigation device based on time grating angle measurement. The single-axis rotation modulation device includes a torque motor, a conductive slip ring, a time grating encoder, an angle measurement control circuit, and a servo drive circuit; wherein,

[0007] The torque motor serves as a rotation execution component. Its rotation shaft is connected to the inertial measurement component through a mounting table, and drives the inertial measurement component to rotate through the mounting table;

[0008] The conductive slip ring is installed on the rotation shaft of the torque motor and is used to realize signal transmission between the inertial measurement component and an external control device during rotation;

[0009] The time grating encoder serves as an angle measurement sensor and includes a stator and a rotor; the stator is connected to the torque motor frame, and the rotor is connected to the torque motor rotation shaft, and is used to measure the angle by which the single-axis rotation modulation device drives the inertial measurement component to rotate;

[0010] The angle measurement control circuit includes an SOC main processor; the programmable logic PL terminal of the SOC main processor is used to realize decoding of the angle signal of the time grating encoder to read the angle value by which the single-axis rotation modulation device drives the inertial measurement component to rotate, and the ARM terminal of the SOC main processor is used to realize a control algorithm, perform a control logic closed loop through this angle value, and output a rotation control signal for the torque motor;

[0011] The servo drive circuit receives the rotation control signal of the torque motor output by the angle measurement control circuit, and performs power amplification on the rotation control signal of the torque motor through drive amplification to form a PWM power signal to drive the torque motor to rotate;

[0012] The single-axis rotation modulation device drives the inertial measurement component to perform periodic rotation through PID triple closed-loop servo control according to a preset rotation strategy, and modulates the error accumulated by the inertial measurement component over time.

[0013] In the above solution, the single-axis rotation modulation device further includes a voltage stabilization circuit. The voltage stabilization circuit performs DC / DC voltage conversion for the time grating encoder, the angle measurement control circuit, and the servo drive circuit to provide the required low-ripple low-voltage power supply.

[0014] In the above solution, the PID triple closed-loop includes:

[0015] A position loop. The position loop outputs a speed reference value according to the error between the desired angle and the actual angle;

[0016] A speed loop. The speed loop outputs a current reference value according to the error between the speed reference value and the actual speed;

[0017] The current loop outputs a torque motor rotation control signal based on the error between the current reference value and the actual current.

[0018] The torque motor rotation control signal is amplified in power through drive amplification to form a PWM power signal to drive the torque motor to rotate, so that the single-axis rotation modulation device drives the inertial measurement unit to rotate to the desired angle.

[0019] In the above solution, the time grating encoder is an absolute non-contact circular time grating.

[0020] In the above solution, the servo drive circuit includes a D / A converter, which converts the digital control signal into an analog signal through the D / A converter.

[0021] In the above solution, the servo drive circuit includes a pulse width modulation amplifier. The pulse width modulation amplifier adopts an H-bridge structure inside and adjusts the duty cycle through the amplitude of the external voltage signal.

[0022] In the above solution, the SOC main processor is a Zynq7020 chip.

[0023] In the above solution, the inertial measurement unit includes a ring laser gyroscope and an accelerometer.

[0024] In a second aspect, the present invention further provides a control method for a single-axis rotation modulation device of an inertial navigation device based on time grating angle measurement, which is applied to the single-axis rotation modulation device of the inertial navigation device based on time grating angle measurement described in any item of the first aspect. The method includes:

[0025] Measure the angle of the single-axis rotation modulation device driving the inertial measurement unit to rotate through the time grating encoder, and transmit the angle signal to the angle measurement control circuit;

[0026] Use the programmable logic PL terminal of the SOC main processor to decode the angle signal of the time grating encoder to read the angle value of the single-axis rotation modulation device driving the inertial measurement unit to rotate;

[0027] Implement a control algorithm through the ARM terminal of the SOC main processor, perform a control logic closed-loop on the read angle value, output a torque motor rotation control signal, and the amplifier circuit amplifies the torque motor rotation control signal in power to form a PWM power signal to drive the torque motor to rotate; the single-axis rotation modulation device drives the inertial measurement unit to perform periodic rotation through PID three-closed-loop servo control according to a pre-set rotation strategy, and modulates the error accumulated by the inertial measurement unit over time.

[0028] In a third aspect, the present invention further provides an inertial navigation device, which includes the single-axis rotation modulation device of the inertial navigation device based on time grating angle measurement described in any item of the first aspect.

[0029] Generally speaking, compared with the prior art, the above technical solution conceived by the present invention can achieve the following beneficial effects:

[0030] The present invention provides a single-axis rotation modulation device for an inertial navigation device based on time grating angle measurement. By measuring the change of the time grating signal with a time grating encoder, it can achieve precise measurement of the rotation angle without relying on mechanical contact or optical reflection. Compared with traditional grating angle measurement, it has advantages such as resistance to oil pollution and water vapor in harsh environments. Compared with traditional resolvers, it has advantages such as simple structure installation and decoding method, high measurement accuracy (can reach 1 arcsecond and below), and good anti-interference performance.

[0031] Using the SOC chip (Zynq7020) as the main processor to design the angle measurement and control circuit, compared with the angle measurement and control circuit designed with traditional DSP+FPGA / CPLD as the main processor, it has higher integration, higher reliability, lower power consumption, and lower cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a control flowchart of a single-axis rotation modulation device for an inertial navigation device based on time grating angle measurement provided by an embodiment of the present application;

[0033] Figure 2 It is a schematic diagram of a PID three-closed-loop control method provided by an embodiment of the present application;

[0034] Figure 3 It is a software design diagram of a position loop control provided by an embodiment of the present application;

[0035] Figure 4 It is a software design diagram of a speed loop control provided by an embodiment of the present application;

[0036] Figure 5 It is a software design diagram of a D / A conversion part provided by an embodiment of the present application;

[0037] Figure 6 It is a circuit design diagram of a drive amplifier and current loop provided by an embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0038] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. Based on the embodiments provided in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the scope of protection of the present invention.

[0039] Obviously, the accompanying drawings in the following description are only some examples or embodiments of the present application. For those of ordinary skill in the art, without creative efforts, the present application can also be applied to other similar scenarios based on these drawings. In addition, it can also be understood that although the efforts made in such a development process may be complex and lengthy, for those of ordinary skill in the art related to the content disclosed in the present application, some design, manufacturing, or production changes based on the technical content disclosed in the present application are only conventional technical means and should not be understood as insufficient disclosure of the content of the present application.

[0040] In the present application, the mention of "embodiment" means that the specific features, structures, or characteristics described in connection with the embodiment can be included in at least one embodiment of the present application. The appearance of this phrase at various positions in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those of ordinary skill in the art explicitly and implicitly understand that the embodiments described in the present application can be combined with other embodiments without conflict.

[0041] Unless otherwise defined, the technical terms or scientific terms involved in the present application should have the ordinary meaning understood by those of ordinary skill in the technical field to which the present application belongs. The terms "a", "an", "one", "the", and similar words involved in the present application do not indicate a limitation of quantity and can represent a singular or plural number. The terms "include", "comprise", "have", and any variations thereof involved in the present application are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or device that includes a series of steps or modules (units) is not limited to the listed steps or units, but may further include unlisted steps or units, or may further include other steps or units inherent to these processes, methods, products, or devices. The terms "connect", "be connected", "couple", and similar words involved in the present application are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The term "plurality" involved in the present application refers to two or more. "And / or" describes the association relationship of associated objects and indicates that three relationships can exist. For example, "A and / or B" can represent: A exists alone, A and B exist simultaneously, and B exists alone. The character " / " generally indicates that the associated objects before and after are in an "or" relationship. The terms "first", "second", "third", etc. involved in the present application are only used to distinguish similar objects and do not represent a specific order for the objects.

[0042] The present application provides a single-axis rotation modulation device for an inertial navigation device based on time grating angle measurement, as Figure 1As shown in the figure, the device mainly consists of a torque motor, a conductive slip ring, a time grating encoder, an angle measurement and control circuit, a servo drive circuit, a voltage stabilization circuit, etc.

[0043] The torque motor serves as the rotating execution component of the single-axis rotation modulation device. Its rotating shaft is fixedly connected to the inertial measurement assembly through the mounting table, and drives the inertial measurement assembly mounted on it to rotate through the mounting table.

[0044] The conductive slip ring is installed on the rotating shaft of the torque motor. Its main function is to communicate the signals of the inertial measurement assembly with external control devices during rotation. These signals include navigation raw data signals, navigation solution signals, rotation angle signals, control signals, etc., ensuring that the lines are not entangled during the rotation of the rotation modulation device, and the signal transmission between the inertial measurement assembly and the external control device is continuous and reliable.

[0045] The time grating encoder is used as an angle measurement sensor. The stator of the time grating encoder is fixedly connected to the motor frame, and the rotor is fixedly connected to the motor rotating shaft. The rotation angle of the rotating device can be measured through the time grating encoder.

[0046] The decoding of the time grating angle signal is realized by using the programmable logic PL terminal on the SOC main processor (Zynq7020) of the angle measurement control circuit, and the angle value of the rotating device driving the inertial measurement assembly to rotate is read. The ARM terminal of the SOC main processor of the angle measurement control circuit realizes the control algorithm, and the control logic closed-loop is carried out through the measured angle value, and the control signal for the motor to rotate is output.

[0047] The servo drive circuit is a power amplification circuit. It receives the control signal for the motor to rotate output by the angle measurement control circuit, and amplifies the power of this control signal through drive amplification to form a PWM power signal to drive the torque motor to rotate.

[0048] The voltage stabilization circuit performs DC / DC voltage conversion for the time grating encoder, the angle measurement control circuit, and the servo drive circuit, and provides a low-ripple low-voltage power supply required by each module.

[0049] As one of the core components of the inertial navigation device, the single-axis rotation modulation device drives the inertial measurement assembly to perform periodic rotation through PID three-closed-loop servo control, modulates the errors accumulated by the inertial sensors over time, and improves the accuracy performance of the inertial navigation device.

[0050] In summary, the present application provides a single-axis rotation modulation device for an inertial navigation device based on time grating angle measurement. By measuring the change of the time grating signal with a time grating encoder, accurate measurement of the rotation angle can be achieved without relying on mechanical contact or optical reflection. Compared with traditional grating angle measurement, it has advantages such as resistance to oil contamination, water vapor, and other harsh environments. Compared with traditional resolvers, it has the advantages of simple structure installation and decoding method, high measurement accuracy (up to 1 arc second and below), and good anti-interference performance.

[0051] The present application uses an SOC chip (Zynq7020) as the main processor to design the angle measurement and control circuit. Compared with the angle measurement and control circuit designed with traditional DSP+FPGA / CPLD as the main processor, it has higher integration, higher reliability, lower power consumption, and lower cost.

[0052] The present application also provides a control method for a single-axis rotation modulation device for an inertial navigation device based on time grating angle measurement. The single-axis rotation device drives the inertial measurement component to perform periodic rotation through PID triple closed-loop servo control according to a pre-set rotation strategy (such as forward and reverse rotation and combination of rotation and stop), which can eliminate the constant errors of inertial sensor devices (laser gyroscopes and accelerometers) in the direction perpendicular to the rotation axis.

[0053] The errors of inertial sensitive devices will affect the navigation error only when they are equivalent in the navigation system during navigation solution. For the constant error in the horizontal direction, if the inertial sensitive device rotates 180°, the constant error equivalent in the navigation system is equal in magnitude and opposite in direction compared with that before rotation, that is, the influence on the navigation error changes from positive to negative or from negative to positive. In this way, within a specific rotation period, the errors of inertial sensitive devices equivalent in the navigation system are canceled in the sense of integration, and the navigation error is suppressed. This is the basic principle of rotation modulation.

[0054] The hardware part of the angle measurement and control circuit in this embodiment mainly consists of an on-board power supply circuit, a core SOC main processor circuit, a parameter and program storage circuit, a level conversion circuit, etc. The software part mainly consists of a signal demodulation module and a servo control module based on the programmable PL end of the SOC.

[0055] Figure 1It is the control flow chart of a rotation modulation device based on a time grating angle sensor. The angle sensor uses the absolute non-contact circular time grating of Guoce Time Grating Company, a general technology company. This angle sensor has a resolution of 26 bits (67108864 pulses per revolution = 0.019 arcseconds) and uses the Biss C protocol for data transmission. The programmable logic PL terminal of the SOC core processor is used to decode the time grating angle Biss C signal, read the angle value of the rotation mechanism driving the inertial measurement unit to rotate. At the same time, the ARM terminal of the SOC main processor implements the control algorithm, forms a control logic closed-loop through the measured angle value, and outputs signals such as motor rotation and braking.

[0056] Figure 2 It is the structural block diagram of the PID three-closed-loop control method. PID three-closed-loop control is an automatic control strategy that combines three control links: proportional (P), integral (I), and derivative (D) to achieve high-precision and high-dynamic response control effects. There are three feedback control loops in the three-closed-loop control system, including the position loop (outer loop), speed loop (middle loop), and current loop (inner loop). The position loop is the position or angle information. Its input is the error between the desired position and the actual position, and the output serves as the reference input for the speed loop; the speed loop is the speed of the control system. Its input is the error between the speed reference value output by the position loop and the actual speed, and the output serves as the reference input for the current loop; the current loop is the current or torque of the control system. Its input is the error between the current reference value output by the speed loop and the actual current, and the output directly controls the motor. Each control loop can be implemented using a PID controller. The output of the PID controller consists of three parts:

[0057] Proportional term (P): It is proportional to the current error, quickly responds to system changes, but may cause steady-state errors or oscillations.

[0058] Integral term (I): Integrates the accumulation of errors to eliminate steady-state errors, but may introduce overshoot or hysteresis.

[0059] Derivative term (D): Differentiates the rate of change of the error, suppresses oscillations, and improves system stability.

[0060] The output formula of the PID controller is: u(t) = Kp×e(t) + Ki×∫e(t)dt + Kd×de(t) / dt, where u(t) is the output of the controller, e(t) is the error (expected value minus the actual value), and Kp, Ki, and Kd are the gain coefficients of proportional, integral, and derivative respectively.

[0061] Figure 3For the software design of the position loop control in the PID three-closed-loop control method, the position loop is the outermost loop of this control system. It is the position setting and adjustment link. The PID input inside its loop is directly the output of the speed loop, and its feedback signal is taken from the angle measurement value of the encoder. Since the internal output of the position control loop is the setting of the speed loop, in the position control mode, the system performs operations on all three loops. At this time, the system has the largest amount of computation and the slowest dynamic response speed.

[0062] Figure 4 For the software design of the speed loop control in the PID three-closed-loop control method, the speed loop is the middle loop of the servo control system. It performs negative feedback PID regulation through the difference of the encoder position signals. The PID input inside its loop is the output of the current loop. Therefore, when the speed loop is controlled, it includes both the speed loop and the current loop. While controlling the speed and position, the system is actually also controlling the current (torque) to achieve the corresponding control of the speed and position.

[0063] Figure 5 For the software design of the D / A conversion part, the D / A converter mainly realizes the conversion of the digital quantity of PID regulation into an analog quantity, which is amplified by the power amplification circuit and then drives the motor to move. In this embodiment, the D / A uses the AD5754AREZ conversion chip of ADI Company, and according to the design requirements of this design, it is initialized and configured as a voltage output type digital-to-analog converter with 16-bit serial input, four-channel output, and a full-scale output of 10V.

[0064] Figure 6 For the drive amplification and current loop circuit design, the drive circuit uses the hybrid integrated switch amplifier WSA03GM of Weijing Electronics Company as the main amplifier. This switch amplifier is a pulse width modulation type amplifier. It uses an H-bridge structure inside, and the bridge arms use all N-channel switching tubes, which has the characteristics of high efficiency and low power consumption. And a fixed dead time is set through high-precision thick film resistors to protect the bridge arms. A fixed-frequency triangular wave generator is integrated inside the module, and the duty cycle is adjusted by the amplitude of the external voltage signal. At the same time, the innermost current loop of this system uses hardware design.

[0065] This application also provides an inertial navigation device. This inertial navigation device includes the single-axis rotation modulation device for inertial navigation equipment based on time grating angle measurement described in the above device embodiment, and uses the control method in the above method embodiment to control the periodic rotation of the inertial measurement unit, cancel the constant error of the inertial device, and improve the navigation accuracy.

[0066] It should be noted that according to the needs of implementation, each step / component described in this application can be split into more steps / components, or two or more steps / components or partial operations of steps / components can be combined into new steps / components to achieve the purpose of the present invention.

[0067] Those skilled in the art can easily understand that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A single-axis rotation modulation device for an inertial navigation device based on time grating angle measurement, characterized in that, The single-axis rotation modulation device includes a torque motor, a conductive slip ring, a time grating encoder, an angle measurement control circuit, and a servo drive circuit; among them, The torque motor serves as a rotational execution component, and its rotating shaft is connected to the inertial measurement unit through a mounting table, and drives the inertial measurement unit to rotate through the mounting table; The conductive slip ring is installed on the rotating shaft of the torque motor and is used to achieve signal transmission between the inertial measurement unit and an external control device during rotation; The time grating encoder serves as an angle measurement sensor and includes a stator and a rotor; the stator is connected to the torque motor frame, and the rotor is connected to the torque motor rotating shaft, and is used to measure the angle of the single-axis rotation modulation device driving the inertial measurement unit to rotate; The angle measurement control circuit includes an SOC main processor; the programmable logic PL terminal of the SOC main processor is used to decode the angle signal of the time grating encoder to read the angle value of the single-axis rotation modulation device driving the inertial measurement unit to rotate, and the ARM terminal of the SOC main processor is used to implement a control algorithm, perform a control logic closed-loop through this angle value, and output a torque motor rotation control signal; The servo drive circuit receives the torque motor rotation control signal output by the angle measurement control circuit, and amplifies the power of the torque motor rotation control signal through an amplifier circuit to form a PWM power signal to drive the torque motor to rotate; The single-axis rotation modulation device drives the inertial measurement unit to perform periodic rotation through PID triple closed-loop servo control according to a preset rotation strategy, and modulates the error accumulated by the inertial measurement unit over time.

2. The single-axis rotation modulation device for an inertial navigation device based on time grating angle measurement according to claim 1, wherein The single-axis rotation modulation device further includes a voltage stabilizing circuit, and the voltage stabilizing circuit performs DC / DC voltage conversion for the time grating encoder, the angle measurement control circuit, and the servo drive circuit to provide the required low-ripple low-voltage power supply.

3. The single-axis rotation modulation device for an inertial navigation device based on time grating angle measurement according to claim 1, wherein, The PID triple closed-loop includes: A position loop, and the position loop outputs a speed reference value according to the error between the desired angle and the actual angle; A speed loop, and the speed loop outputs a current reference value according to the error between the speed reference value and the actual speed; A current loop, and the current loop outputs a torque motor rotation control signal according to the error between the current reference value and the actual current; The torque motor rotation control signal is amplified in power through drive amplification to form a PWM power signal to drive the torque motor to rotate, so that the single-axis rotation modulation device drives the inertial measurement unit to rotate to the desired angle.

4. The single-axis rotation modulation device for an inertial navigation device based on time grating angle measurement according to claim 1, wherein, The time grating encoder is an absolute non-contact circular time grating.

5. The single-axis rotation modulation device for an inertial navigation device based on time grating angle measurement according to claim 1, wherein, The servo drive circuit includes a D / A converter, and the digital control signal is converted into an analog signal through the D / A converter.

6. The single-axis rotation modulation device for an inertial navigation device based on time grating angle measurement according to claim 1, wherein, The servo drive circuit includes a pulse width modulation type amplifier, and the pulse width modulation type amplifier internally adopts an H-bridge structure, and adjusts the duty cycle through the amplitude of an external voltage signal.

7. The single-axis rotation modulation device for an inertial navigation device based on time grating angle measurement according to claim 1, characterized in that, The SOC main processor is a Zynq7020 chip.

8. The single-axis rotation modulation device for an inertial navigation device based on time grating angle measurement according to claim 1, wherein, The inertial measurement unit includes a ring laser gyroscope and an accelerometer.

9. A control method for a single-axis rotation modulation device used in an inertial navigation device based on time grating angle measurement, which is applied to the single-axis rotation modulation device used in the inertial navigation device based on time grating angle measurement according to any one of claims 1 to 8, characterized in that, The method includes: Measuring the angle of the single-axis rotation modulation device driving the inertial measurement unit to rotate through the time grating encoder, and transmitting the angle signal to the angle measurement control circuit; Using the programmable logic PL terminal of the SOC main processor to implement the decoding of the angle signal of the time grating encoder to read the angle value of the single-axis rotation modulation device driving the inertial measurement unit to rotate; The control algorithm is implemented through the ARM side of the SOC main processor, and the read angle value is subjected to a control logic closed-loop to output a control signal for driving the torque motor to rotate. The control signal for driving the torque motor to rotate is amplified in power through an amplifier circuit to form a PWM power signal to drive the torque motor to rotate; according to the preset rotation strategy, the single-axis rotation modulation device drives the inertial measurement unit to perform periodic rotation through PID three-closed-loop servo control, and modulates the error accumulated by the inertial measurement unit over time.

10. An inertial navigation device, characterized in that, The inertial navigation device includes the single-axis rotation modulation device for the inertial navigation device based on time-grating angle measurement according to any one of claims 1 to 8.

Images