Star-aligning stability control method based on servo motor control

Abstract

The invention discloses a satellite stability control method based on servo motor control, and relates to the field of communication-in-motion systems, and the satellite stability control method based on servo motor control comprises the following steps: step 1, tracking the real-time attitude change of an antenna through an inertial navigation module, and outputting the real-time attitude change to a control panel; 2, calculating the theoretical angle of the antenna through Beidou data, and outputting the theoretical angle to a control panel; 3, the control panel controls a driver to control a servo motor of a transmission mechanism through a three-ring control algorithm, so that the axis of a real-time antenna surface is kept consistent with a theoretical angle obtained through Beidou data calculation; compared with the prior art, the method has the beneficial effects that based on three-ring superposition PID control logic of a current ring, a speed ring and a position ring, the limitation of single-ring PID control of a stepping motor can be effectively overcome, and stable pointing and communication performance of an antenna in various complex environments can be ensured; and under the condition of signal interruption, the direction to the target satellite can still be kept.

Description

Technical Field

[0001] The present invention relates to the field of mobile communication systems, and specifically to a satellite alignment and stabilization control method based on servo motor control. Background Art

[0002] A mobile communication system is a technology that can maintain satellite communication during movement and is widely used in military, emergency communication, maritime communication and other fields. Its core lies in ensuring that the antenna always accurately points at the satellite during movement through antenna stabilization control technology, thereby maintaining the stability of the communication link. However, this process faces many challenges, such as platform movement interference, environmental interference, and requirements for high-precision pointing, etc.

[0003] The antenna stabilization control technology is developed to solve the above problems and mainly relies on the following key technologies to achieve:

[0004] Attitude perception: Real-time monitoring of the attitude changes of the carrier through sensors such as Beidou units, inertial measurement units (IMUs), gyroscopes, and accelerometers.

[0005] Link monitoring: Obtaining the change in the real-time satellite beacon signal strength through a beacon receiver.

[0006] Stabilization algorithm: Using algorithms such as PID control, fuzzy control, or adaptive control to adjust the pointing of the antenna in real time.

[0007] Actuator: Quickly adjusting the attitude of the antenna through actuators such as stepper motors.

[0008] In the early stabilization control designs, stepper motor solutions were mostly used for actuators. Its advantages include simple control logic, low cost, and large low-speed torque, etc.

[0009] Using a signal stepper motor as an actuator, in complex scenarios, the signal may be blocked or shielded by buildings, terrain, or other obstacles, resulting in communication interruption (for example, during the stabilization control process, the stepper motor will experience jitter and large moment of inertia during high-speed rotation and steering, which will generate additional angular change components, affecting the accuracy of inertial navigation monitoring, resulting in errors in the stabilization control process. Under the accumulation of such long-term errors, if the signal is blocked or shielded by the outside world in the scenario where the device is located, it may cause pointing deviation in a short time, causing the attitude of the mobile communication antenna to change violently, making the signal unstable or even completely lost, and needs to be improved). Summary of the Invention

[0010] The purpose of the present invention is to provide a satellite alignment and stabilization control method based on servo motor control to solve the problems raised in the above background art.

[0011] To achieve the above object, the present invention provides the following technical solutions:

[0012] A satellite alignment and stabilization control method based on servo motor control, comprising the following steps:

[0013] Step 1, the inertial navigation module tracks the real-time attitude change of the antenna and outputs it to the control board;

[0014] Step 2, the theoretical angle of the antenna is calculated through Beidou data and output to the control board;

[0015] Step 3, the control board controls the driver to realize the servo motor control of the transmission mechanism through a three-loop control algorithm, so that the axis of the real-time antenna surface is consistent with the theoretical angle calculated from the Beidou data.

[0016] As a further solution of the present invention: in Step 3, the axis of the antenna surface includes an azimuth axis, a pitch axis, a roll axis, and a polarization axis.

[0017] As a further solution of the present invention: in Step 3, the core idea of the three-loop control algorithm is hierarchical control. Each loop is responsible for different control objectives. The response speed of the inner loop is faster than that of the outer loop. The output of the outer loop is used as the input of the inner loop. The current loop is the innermost loop, the speed loop is the middle loop, and the position loop is the outermost loop;

[0018] The position loop is used to control the position of the motor and output a speed command;

[0019] The speed loop is used to control the rotation speed of the motor and output a current command;

[0020] The current loop is used to control the current (torque) of the motor and output a voltage command.

[0021] As a further solution of the present invention: in Step 3, the current loop requires the fastest response speed (high bandwidth design is required). The response speed of the speed loop is second only to the current loop but higher than the position loop. The response speed of the position loop is the slowest, which determines the final positioning accuracy of the system.

[0022] As a further solution of the present invention: in Step 3, the working process of the current loop receives the input speed loop current command I ref and the actual current I act , calculates the voltage command V ref through a PID controller to drive the servo motor. At this time, the calculation formula of the PID controller is:

[0023] V ref = Kp i ·(I ref - I act ) + Ki i ·∫(I ref - Iact )dt (1).

[0024] As a further solution of the present invention: in step 3, during the working process of the speed loop, it receives the input position loop speed command ω ref and the actual speed ω agt , calculates the current command I ref through a PID controller, and transmits it to the current loop. At this time, the calculation formula of the PID controller is:

[0025] I ref = Kp v ·(ω ref - ω act ) + Ki v ·∫(ω ref - ω act )dt (2).

[0026] As a further solution of the present invention: in step 3, during the working process of the position loop, it receives the input theoretical position command θ ref and the actual position θ act , calculates the speed command ω ref through a PID controller, and transmits it to the speed loop. At this time, the calculation formula of the PID controller is:

[0027]

[0028] Compared with the prior art, the beneficial effects of the present invention are as follows: Based on the three-loop superimposed PID control logic of the current loop, speed loop and position loop, the present invention can effectively overcome the limitations of the single-loop PID control of the stepper motor, ensuring the stable pointing and communication performance of the antenna in various complex environments; by collecting Beidou positioning information, inertial navigation attitude data, and combining the feedback of the beacon signal change to form a closed-loop control, it can adjust the angles of the azimuth, elevation, roll and polarization servo motors in real time, so as to accurately adjust the attitude of the antenna surface and ensure the stable pointing between the antenna and the target satellite; when the beacon signal is blocked or shielded, the system will rely on the change of Beidou positioning information and inertial navigation attitude data to directly perform open-loop compensation on each servo motor, ensuring that the antenna can still maintain the pointing to the target satellite within a certain period of time in case of signal interruption and avoiding communication interruption. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a working schematic diagram of a satellite alignment and stabilization control method based on servo motor control. DETAILED DESCRIPTION OF THE INVENTION

[0030] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0031] Please refer to Figure 1 , a satellite alignment and stabilization control method based on servo motor control, comprising the following steps:

[0032] Step 1: The inertial navigation module tracks the real-time attitude change of the antenna and outputs it to the control board. The inertial navigation module is a navigation device based on an inertial measurement unit (IMU), which calculates the position, velocity, and attitude of an object by measuring acceleration and angular velocity. It does not rely on external signals (such as GPS), so it can still work in a signal-free environment and is widely used in aerospace, unmanned aerial vehicles, vehicle navigation, robots, and other fields.

[0033] Step 2: Calculate the theoretical angle of the antenna through Beidou data and output it to the control board. The Beidou satellite system calculates the antenna angle (including azimuth and elevation angles) by receiving the geometric relationship and signal characteristics between the antenna and the satellite.

[0034] Step 3: The control board controls the driver to achieve servo motor control of the transmission mechanism through a three-loop control algorithm, so that the axis of the real-time antenna surface is consistent with the theoretical angle calculated from the Beidou data.

[0035] In this embodiment: Please refer to Figure 1 , in Step 3, the axis of the antenna surface includes the azimuth axis, elevation axis, roll axis, and polarization axis.

[0036] In this embodiment: Please refer to Figure 1 , in Step 3, the core idea of the three-loop control algorithm is hierarchical control. Each loop is responsible for different control objectives. The response speed of the inner loop is faster than that of the outer loop. The output of the outer loop is used as the input of the inner loop. The current loop is the innermost loop, the speed loop is the middle loop, and the position loop is the outermost loop;

[0037] The position loop is used to control the position of the motor and output a speed command;

[0038] The speed loop is used to control the rotational speed of the motor and output a current command;

[0039] The current loop is used to control the current (torque) of the motor and output a voltage command.

[0040] In this embodiment: Please refer to Figure 1, in step 3, the current loop requires the fastest response speed (high-bandwidth design is needed). The response speed of the speed loop is second only to that of the current loop but higher than that of the position loop. The position loop has the slowest response speed, which determines the final positioning accuracy of the system.

[0041] In this embodiment: Please refer to Figure 1 , in step 3, for the working process of the current loop, it receives the input speed-loop current command I ref and the actual current I act , and calculates the voltage command V ref through a PID controller to drive the servo motor. At this time, the calculation formula of the PID controller is:

[0042] V ref = Kp i ·(I ref - I act ) + Ki i ·∫(I ref - I act )dt (1).

[0043] The function of the current loop is to control the current of the motor to ensure that the torque output by the motor is consistent with the command. The control objective is to quickly track the current command and suppress current fluctuations.

[0044] In this embodiment: Please refer to Figure 1 , in step 3, for the working process of the speed loop, it receives the input position-loop speed command ω ref and the actual speed ω agt , and calculates the current command I ref through a PID controller and transmits it to the current loop. At this time, the calculation formula of the PID controller is:

[0045] I ref = Kp v ·(ω ref - ω act ) + Ki v ·∫(ω ref - ω act )dt (2).

[0046] The function of the speed loop is to control the rotational speed of the motor to ensure that the rotational speed of the motor is consistent with the command. The control objective is to quickly track the speed command and suppress speed fluctuations.

[0047] In this embodiment: Please refer to Figure 1 , in step 3, for the working process of the position loop, it receives the input theoretical position command θ ref and the actual position θ act , and calculates the speed command ω ref through a PID controller and transmits it to the speed loop. At this time, the calculation formula of the PID controller is:

[0048]

[0049] The function of the position loop is to control the position of the motor and ensure that the motor position is consistent with the command. The control objective is to accurately track the position command and achieve high-precision positioning.

[0050] The present invention addresses the problem that the signal of the existing satellite communication antenna in motion becomes unstable or even completely lost due to drastic changes in attitude. Generally, there are two main reasons for such drastic changes:

[0051] 1. The carrier on which the device is located makes large-scale movements, turns, or tilts.

[0052] 2. In the scenario where the device is located, the signal is blocked or shielded by the outside world.

[0053] For the first aspect, it is necessary to stabilize the channel with the target satellite by controlling the attitude of the antenna surface. The implementation method is to collect data such as Beidou information and inertial navigation attitude, and form a closed-loop control by combining the beacon signal obtained by feedback. Furthermore, the angles of the azimuth, elevation, roll, and polarization servo motors are adjusted in real time, and finally the attitude adjustment is completed.

[0054] For the second problem, since the beacon signal is blocked or shielded, it is necessary to directly perform open-loop compensation on each servo motor through the changes in Beidou information and inertial navigation attitude. Ensure that the pointing to the target satellite is still maintained within a certain period of time.

[0055] Compared with the products using the stepper motor scheme originally, the servo motor has obvious advantages in solving these two problems. For example, during the stabilization control process, the stepper motor will show jitter and large moment of inertia during high-speed rotation and turning, which will generate additional angular change components, affecting the accuracy of inertial navigation monitoring and leading to errors in the stabilization control process. Under the accumulation of such long-term errors, if there is shielding or occlusion again, it may lead to pointing deviation in a short time.

[0056] Compared with the single-loop PID control logic of the original stepper motor, the servo motor of the present invention adopts the logic of superimposing the current loop, speed loop, and position loop for PID control. In comparison, the latter has the remarkable characteristics of high control accuracy, fast dynamic response, and strong anti-interference ability.

[0057] The present invention has conducted in-depth research and improvement on the problem that the signal of the existing satellite communication antenna in motion becomes unstable or even completely lost during drastic attitude changes. It can be mainly attributed to the following two aspects:

[0058] 1. Large-scale movement, turning, or tilting of the carrier on which the device is located: When the carrier makes large-scale movements, the attitude of the antenna will change drastically, affecting the signal stability.

[0059] 2. The signal is blocked or shielded by the external environment: In complex scenarios, the signal may be blocked or shielded by buildings, terrain, or other obstacles, resulting in communication interruption.

[0060] For the first problem, the present invention forms a closed-loop control by collecting Beidou positioning information, inertial navigation attitude data, and combining the feedback of beacon signal changes. It can adjust the angles of azimuth, pitch, roll, and polarization servo motors in real time, thereby accurately adjusting the attitude of the antenna surface to ensure the stability of the pointing between the antenna and the target satellite.

[0061] For the second problem, when the beacon signal is blocked or shielded, the system will directly perform open-loop compensation on each servo motor depending on the changes in Beidou positioning information and inertial navigation attitude data. This compensation mechanism can ensure that the antenna can still maintain the pointing to the target satellite within a certain period of time in case of signal interruption, avoiding communication interruption.

[0062] Compared with the traditional stepper motor solution, the servo motor has significant advantages in solving the above problems. Stepper motors are prone to jitter and large moment of inertia during high-speed rotation and steering, which will introduce additional attitude change components, affecting the accuracy of inertial navigation detection, and then leading to errors in the stabilization control process. The errors accumulated over a long time may cause the antenna to deviate in pointing within a short time when the signal is suddenly blocked or shielded, seriously affecting the communication quality.

[0063] In contrast, the servo motor control system adopted by the present invention is based on the three-loop superposition PID control logic of current loop, speed loop, and position loop. This multi-loop control structure has significant characteristics such as high control accuracy, fast dynamic response, and strong anti-interference ability, and can effectively overcome the limitations of the single-loop PID control of stepper motors, ensuring the stable pointing and communication performance of the antenna in various complex environments.

[0064] Through the above improvements, the present invention significantly improves the stability and reliability of the antenna in motion communication, and is applicable to high-dynamic and high-precision communication scenarios.

[0065] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting.

[0066] In addition, it should be understood that although this specification is described in terms of embodiments, not every embodiment contains only one independent technical solution. This narrative manner of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A satellite stabilization control method based on servo motor control, characterized in that: The satellite stabilization control method based on servo motor control comprises the following steps: Step 1: Track the real-time attitude changes of the antenna through the inertial navigation module and output it to the control board; Step 2: Calculate the theoretical angle of the antenna through Beidou data and output it to the control board; Step 3: The control board controls the driver to realize the servo motor control of the transmission mechanism through the three-loop control algorithm, so that the axis of the real-time antenna surface is consistent with the theoretical angle calculated by Beidou data.

2. The satellite stabilization control method based on servo motor control according to claim 1 is characterized in that: In step 3, the axes of the antenna surface include an azimuth axis, a pitch axis, a roll axis, and a polarization axis.

3. The satellite stabilization control method based on servo motor control according to claim 1 is characterized in that: In step 3, the core idea of ​​the three-loop control algorithm is hierarchical control. Each loop is responsible for different control targets. The response speed of the inner loop is faster than that of the outer loop. The output of the outer loop is used as the input of the inner loop. The current loop is the innermost loop, the speed loop is the middle loop, and the position loop is the outermost loop. Position loop, used to control the position of the motor and output speed instructions; Speed ​​loop, used to control the speed of the motor and output current instructions; The current loop is used to control the motor current and output voltage instructions.

4. The satellite stabilization control method based on servo motor control according to claim 3 is characterized in that: In step 3, the current loop is required to have the fastest response speed. The response speed of the speed loop is second to that of the current loop, but higher than that of the position loop. The response speed of the position loop is the slowest, which determines the final positioning accuracy of the system.

5. The satellite stabilization control method based on servo motor control according to claim 3 or 4, characterized in that: In step 3, the current loop works by receiving the input speed loop current command I ref and the actual current I act , the voltage command V is calculated by the PID controller ref , used to drive the servo motor, the calculation formula of the PID controller is: V ref =Kp i ·(I ref -I act )+Ki i ·∫(I ref -I act )dt (1)。 6. The satellite stabilization control method based on servo motor control according to claim 3 or 4, characterized in that: In step 3, the speed loop works by receiving the input position loop speed command ω ref and the actual speed ω agt , the current command I is calculated by the PID controller ref , passed to the current loop, the calculation formula of the PID controller is: I ref =Kp v ·(ω ref -oh act )+Ki v ·∫(ω ref -oh act )dt (2).

7. The satellite stabilization control method based on servo motor control according to claim 3 or 4, characterized in that: In step 3, the position loop works by receiving the input theoretical position command θ ref and the actual position θ act , the speed command ω is calculated by the PID controller ref , passed to the speed loop, the calculation formula of the PID controller is:

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