Modularized electric steering engine system

Abstract

The invention relates to a modularized electric steering engine system which is characterized in that the modularized electric steering engine system comprises an upper computer, a power supply, a main control board and a steering engine, the main control board is provided with a controller, and the steering engine comprises a driving board, a motor, a speed reducer, a rudder sheet and a potentiometer; the controller inputs the target position acquired by the upper computer, the current position of the rudder sheet acquired by the potentiometer and the bus current of the motor acquired by the current sampling circuit into a preset algorithm structure to execute a fuzzy PID control algorithm so as to obtain an optimal control coefficient and generate a PWM wave with a corresponding duty ratio, and the driving board drives the motor to rotate according to the PWM wave; the speed reducer is connected with a motor, and an output shaft is provided with a rudder sheet for bearing a load. Based on position and current feedback, the fuzzy PID control algorithm is executed through the algorithm structure, the optimal control coefficient is obtained, and the response rate and accuracy are effectively improved. According to the invention, position protection logic and overcurrent protection logic are provided, so that the operation safety and reliability of the system are effectively improved.

Description

Technical Field

[0001] This invention relates to the field of servo motor technology, and more specifically, to a modular electric servo motor system. Background Technology

[0002] Servo systems can be classified into pneumatic servo servos, hydraulic servo servos, and electric servo servos according to their power source. Compared with pneumatic and hydraulic servo servos, electric servo servos have advantages such as simple structure, small size, easy maintenance, convenient control, high control precision, and fast dynamic response. They are widely used in miniature intelligent projectiles and UAVs.

[0003] With the development of precision-guided weapon technology, miniature smart projectiles are playing an increasingly important role on the modern battlefield due to their low cost, high mobility and precision strike capability, making the improvement of their performance particularly crucial. In miniature smart projectiles, the servo system is the core component for achieving ballistic control and attitude adjustment. Since smart projectiles need to operate in various complex weather environments, there is an urgent need for an electric servo system that is accurate and rapid in response and safe and reliable in operation. Summary of the Invention

[0004] Based on the technical problems existing in the background technology, the present invention proposes a modular electric servo system.

[0005] The present invention proposes a modular electric servo system, including a host computer, a power supply, a main control board and a servo motor. The main control board is equipped with a controller, and the servo motor includes a drive board, a motor, a reducer, a servo plate and a potentiometer. The drive board is equipped with multiple drive circuits, an H-bridge circuit and a current sampling circuit. The drive board is electrically connected to the main control board, the motor, and the potentiometer, respectively. The host computer is communicatively connected to the main control board and is used to obtain the target location input by the user; The potentiometer is used to obtain the current position of the rudder plate; The current sampling circuit is used to collect the bus current of the motor; The controller includes multiple microprocessor units. The controller acquires the target position, the current position, and the bus current, and executes a fuzzy PID control algorithm through a preset algorithm structure, and generates a PWM wave with a corresponding duty cycle. The drive board controls the motor to rotate according to the PWM wave; The reducer includes an input end and an output shaft. The input end is connected to the motor, and the rudder is mounted on the output shaft. The reducer is used to change the speed and torque of the rudder, and the rudder is used to bear a preset load. The controller is also equipped with position protection logic and overcurrent protection logic to ensure that the rudder blades operate within a preset standard deflection angle range and that the motor temperature is within a safe temperature range.

[0006] Furthermore, the controller is equipped with an analog-to-digital converter. The current position and the bus current are both analog voltage signals. The analog-to-digital converter is used to convert the analog voltage signals into discrete digital values ​​that the microprocessor unit can recognize and process.

[0007] Furthermore, the algorithm structure includes a linear quadratic regulator, a fuzzy PID control module, and a PWM duty cycle module. The fuzzy PID control algorithm includes obtaining PID weights through the linear quadratic regulator based on the target position, the current position, and the bus current.

[0008] Furthermore, the fuzzy PID control algorithm further includes: adjusting the preset initial control coefficients according to the PID weights by the fuzzy PID control module to obtain the optimal control coefficients, wherein the optimal control coefficients include proportional coefficients, integral coefficients, and derivative coefficients.

[0009] Furthermore, the fuzzy PID control algorithm also includes: generating a PWM wave with a corresponding duty cycle according to the optimal control coefficient through the PWM duty cycle module, and sending the PWM wave to the drive circuit.

[0010] Furthermore, the driving circuit includes a driving chip and is used to amplify the power of the PWM wave.

[0011] Furthermore, the H-bridge circuit is connected to the drive circuit and includes multiple power switches. The PWM wave controls the closing and opening of the power switches to control the operating state of the motor.

[0012] Furthermore, the maximum deflection angle range of the rudder blade should be greater than the standard deflection angle range.

[0013] Furthermore, the controller is electrically connected to the host computer via a preset communication bus, and is used to receive the target position sent by the host computer in real time and send the current position of the rudder blade to the host computer.

[0014] Furthermore, the main control board is also equipped with a power management module, which is used to distribute the power to supply power to the main control board and the servo motor respectively.

[0015] The beneficial effects of this invention are as follows: This invention improves the response speed and accuracy by setting up a host computer within the system to obtain the target position input by the user, a potentiometer to collect the current position of the rudder in real time, and a current sampling circuit to collect the bus current of the motor. Based on the position and current feedback, the controller executes a fuzzy PID control algorithm through an algorithm structure to obtain the optimal control coefficient. The controller also has position protection logic and overcurrent protection logic to ensure that the rudder operates within a preset standard deflection angle range and that the motor temperature is within a safe temperature range, effectively improving the stability and reliability of the system operation. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the present invention will be further described below in conjunction with the accompanying drawings and embodiments. The drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort: Figure 1 This is a system architecture diagram of a modular electric servo system according to an embodiment of the present invention; Figure 2 This is a structural block diagram of a modular electric servo system according to an embodiment of the present invention; Figure 3 This is a block diagram of fuzzy PID control in one embodiment of the present invention; Figure 4 This is a schematic diagram of the driving circuit in one embodiment of the present invention; Figure 5 This is a schematic diagram of an H-bridge circuit in one embodiment of the present invention; Figure 6 This is a system overall power management logic diagram in one embodiment of the present invention. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0018] Please refer to the attached document. Figures 1-6This invention proposes a modular electric servo system, including a host computer, a power supply, a main control board, and a servo motor. The main control board is equipped with a controller, and the servo motor includes a drive board, a motor, a reducer, a servo plate, and a potentiometer. The drive board is equipped with a drive circuit, an H-bridge circuit, and a current sampling circuit. The drive board is electrically connected to the main control board, the motor, and the potentiometer. The host computer is used to acquire the target position input by the user. The potentiometer is used to acquire the current position of the servo plate. The current sampling circuit is used to collect the bus current of the motor. The controller includes multiple microprocessor units. The controller acquires the target position, the current position, and the bus current, and executes a fuzzy PID control algorithm through a preset algorithm structure, generating a PWM wave with a corresponding duty cycle. The drive board controls the motor rotation according to the PWM wave. The reducer includes an input end and an output shaft. The input end is connected to the motor, and the servo plate is mounted on the output shaft. The reducer is used to change the speed and torque of the servo plate, and the servo plate is used to bear a preset load. The controller also has position protection logic and overcurrent protection logic to ensure that the servo plate operates within a preset standard deflection angle range and that the motor temperature is within a safe temperature range.

[0019] In this embodiment, a modular electric servo system includes a host computer, a power supply, a main control board, and servos. The main control board has a controller using an STM32 chip. An isolation circuit is provided between the host computer and the controller to provide electrical isolation. The controller communicates with the host computer via a preset communication bus and is used to receive the target position sent by the host computer in real time and send the current position of the servo blade to the host computer. The servo blade includes a drive board electrically connected to the main controller. The controller has four PWM outputs, and the drive board has four identical sets of isolation circuits, drive circuits, H-bridge circuits, and current sampling circuits. The servo blade also includes four identical sets of motors, reducers, servo blades, and potentiometers. The input terminals of the motors are connected to the H-bridge circuits one by one, the input terminals of the reducers are connected to the output terminals of the motors, and the servo blades are mounted on the output shafts of the reducers. The servo blades are used to carry a preset load.

[0020] Furthermore, a current sampling circuit is located at the motor input terminal to detect the motor bus current, and a potentiometer is located on the reducer output shaft to obtain the current position of the rudder. The controller includes an analog-to-digital converter to perform analog-to-digital conversion on the target position, current position, and motor bus current. The controller executes a fuzzy PID control algorithm through a preset algorithm structure and generates a PWM wave with a corresponding duty cycle. The algorithm structure includes a linear quadratic regulator, a fuzzy PID control module, and a PWM duty cycle module. The linear quadratic regulator obtains PID weights based on the target position, current position, and bus current. The fuzzy PID control module adjusts the preset initial control coefficients according to the PID weights to obtain the optimal control coefficients. The control coefficients include... The controller includes a proportional coefficient Kp, an integral coefficient Ki, and a derivative coefficient Kd. A PWM duty cycle module generates a PWM wave with the corresponding duty cycle based on the optimal control coefficient and sends the PWM wave to the drive circuit. The drive circuit includes a drive chip and amplifies the PWM wave. An H-bridge circuit connects to the drive circuit and includes multiple power switches. The PWM wave controls the closing and opening of the power switches to control the motor's operating state. The controller also includes position protection logic and overcurrent protection logic to ensure the rudder operates within a preset standard deflection angle range and the motor temperature is within a safe temperature range. In this embodiment, the controller acquires and analyzes the real-time rudder position collected by the potentiometer and the real-time motor bus current collected by the current sampling circuit. When the current exceeds the safe range, an alarm is triggered and power is cut off.

[0021] This invention improves the response rate and accuracy by setting up a host computer within the system to obtain the target position input by the user, a potentiometer to collect the current position of the rudder in real time, a current sampling circuit to collect the bus current of the motor, and a controller to obtain the optimal control coefficient by executing a fuzzy PID control algorithm based on position and current feedback. This invention also proposes to set up an isolation circuit, and the controller chip includes multiple independent microprocessor units, which effectively improves the stability and reliability of the system operation.

[0022] Please refer to Figure 1 and Figure 2 The controller is electrically connected to the host computer via a preset communication bus and is used to receive the target position sent by the host computer in real time and send the current position of the rudder blade to the host computer.

[0023] In practical implementation: the user inputs the target position through the host computer, and the controller receives the target position sent by the host computer in real time through the communication bus. At the same time, it sends the current position of the rudder to the host computer at a set period. In a specific embodiment, the host computer refers to a computer system used to control and monitor the slave computer or other terminal devices. In this solution, the host computer adopts a flight control system, the controller adopts an STM32 chip, the communication bus adopts an RS422 bus, and the set period is every 2ms. An isolation circuit is also provided between the host computer and the controller to provide electrical isolation, which helps to improve system safety.

[0024] More specifically, the STM32 chip used in this controller integrates two independent processor cores, namely two microprocessor units (MCUs), which have the advantages of high efficiency and good security. In addition, the chip has four PWM outputs and supports ADC sampling and IIC (Inter-Integrated Circuit), UART (Universal Asynchronous Receiver / Transmitter), and SPI (Serial Peripheral Interface) communication. Among them, PWM is pulse width modulation, which controls the analog circuit by adjusting the duty cycle of the pulse signal, and ADC is an analog-to-digital converter.

[0025] Please refer to Figure 1 and Figure 2 The current sampling circuit is located at the input end of the motor and is used to detect the motor bus current. The potentiometer is located on the output shaft of the reducer and is used to obtain the current position of the rudder. The controller is equipped with an analog-to-digital converter and is used to perform analog-to-digital conversion on the target position, the current position and the motor bus current.

[0026] In specific implementation: the current sampling circuit is located at the input end of the motor and is used to detect the motor bus current. This signal is filtered, converted to digital by an analog-to-digital converter, and then input to the MCU for overcurrent protection to prevent overcurrent damage to the motor and ensure the safe and effective operation of the system; the potentiometer is located on the output shaft of the reducer and is used to obtain the current position of the rudder; both the motor bus current and the current position of the rudder are analog voltage signals; the controller has an analog-to-digital converter and is used to convert the analog voltage signal into discrete digital values ​​that the microprocessor unit can recognize and process; in a specific embodiment, the controller has a timer that generates a 100us timer interrupt as the system control cycle, and performs current and position information acquisition and analog-to-digital conversion every 100us.

[0027] Please refer to Figure 2 and Figure 3The controller executes a fuzzy PID control algorithm through a preset algorithm structure and generates a PWM wave with a corresponding duty cycle. The algorithm structure includes a linear quadratic regulator, a fuzzy PID control module, and a PWM duty cycle module. The linear quadratic regulator is used to obtain PID weights based on the target position, current position, and bus current. The fuzzy PID control module is used to adjust the preset initial control coefficients according to the PID weights and obtain the optimal control coefficients, which include proportional coefficients, integral coefficients, and derivative coefficients. The PWM duty cycle module is used to generate a PWM wave with a corresponding duty cycle based on the optimal control coefficients and send the PWM wave to the drive circuit.

[0028] In practical implementation: such as Figure 3 The diagram shows a fuzzy PID control block diagram. In one embodiment, the fuzzy PID algorithm is as follows: the input r is the angle information value of the target position of the rudder blade, and the output y is the angle information value of the target position of the rudder blade. e and de / dt are obtained through calculation, where e is the current position error signal and de / dt is the position error rate of change signal. The current position error signal and the position error rate of change signal are then input to a linear quadratic regulator. The invention comprises a linear quadratic regulator (LQR) and a fuzzy PID control module. The linear quadratic regulator performs fuzzy inference based on the position error signal and the position error rate of change signal to obtain PID weights, which are then sent to the fuzzy PID control module. The PID weights refer to the dynamic adjustment range of the PID control coefficients, enabling automatic compensation for interference. The PID control coefficients include proportional, integral, and derivative coefficients. The fuzzy PID control module adjusts the preset initial control coefficients according to the PID weights to obtain the optimal control coefficients. The PWM duty cycle module calculates the optimal control coefficients and generates a PWM wave with the corresponding duty cycle, which is then sent to the drive circuit. This invention is based on position closed-loop feedback and uses the fuzzy PID control algorithm as its core. It obtains optimal system parameters through a linear quadratic regulator. Compared with traditional PID control, fuzzy PID control has higher control accuracy, stability, and response speed.

[0029] Please refer to Figures 2-5 The drive circuit includes a drive chip and is used to amplify the power of the PWM wave; the H-bridge circuit is connected to the drive circuit and includes multiple power switches. The PWM wave controls the closing and opening of the power switches to control the running state of the motor.

[0030] In practical implementation: such as Figure 4The diagram shows the schematic of a driver circuit including a driver chip. This driver circuit amplifies the power of the PWM wave. The driver circuit includes capacitors C58, C59, and C61, resistors R29, R33, and R35, a driver chip U13, and a diode D2. The PWM wave is input through port B1 and outputs the amplified PWM wave through ports VH1 and VL1. The amplification factor is changed by adjusting the resistance values. The driver chip U13 is a 2014 driver chip, an insulated-gate bipolar transistor (IGBT), which features high speed, high voltage, and low on-resistance. Among these features, the high voltage means the rated voltage of the driver chip is 1200V, enabling stable operation within a high voltage range; the low on-resistance means the on-resistance of the driver chip is only 0.06-0.25Ω, which reduces energy loss and improves equipment efficiency; in addition, it also has fast switching speed and wide operating range. The fast switching speed means that the driver chip has a fast switching speed, which can realize high-frequency switching mode power supplies and frequency converters; the wide operating range means that the operating temperature range of the driver chip is -55℃ to 150℃, which can adapt to different environmental conditions.

[0031] Furthermore, such as Figure 5 The diagram shows the schematic of an H-bridge circuit. UH1 and UL1 of the H-bridge circuit are input terminals, connected to the VH1 and VL1 ports of the drive circuit. The H-bridge circuit has four MOSFETs Q1, Q2, Q3, and Q4. When switches Q1 and Q4 are closed and Q2 and Q3 are open, the DC motor rotates normally, with this direction of rotation being the positive direction. When switches Q2 and Q3 are closed and Q1 and Q4 are open, the DC motor rotates normally, with this direction of rotation being the negative direction. When switches Q1 and Q2 are closed and Q3 and Q4 are open, or when switches Q3 and Q4 are closed and Q1 and Q2 are open, the DC motor rotates normally. When the switches are open, the DC motor does not rotate. At this time, the motor can be considered to be in a "braking" state. The electromotive force generated by the motor's inertial rotation will be short-circuited, forming a back electromotive force that opposes the motion, thus acting as a "brake". When switches Q1 and Q3 are closed or switches Q2 and Q4 are closed, the power supply is short-circuited, which will burn out the power supply. This situation is strictly prohibited. When all four switches Q1, Q2, Q3 and Q4 are open, the motor is in a "coasting" state. The electromotive force generated by the motor's inertia will not form a circuit and will not generate a back electromotive force that opposes the motion. The motor will rotate due to inertia for a longer period of time.

[0032] Please refer to Figure 1 and Figure 2 The reducer is used to change the speed and torque of the rudder blade. The controller is equipped with position protection logic to ensure that the current position angle of the rudder blade is within the preset standard deflection angle range, and the maximum deflection angle range should be greater than the standard deflection angle range.

[0033] In practical implementation: The reducer includes an input end and an output shaft. The input end of the reducer is connected to the output end of the motor. The rudder is mounted on the output shaft. The reducer is used to change the speed and torque of the rudder, and the rudder is used to bear the preset load. There are many types and forms of reducers, mainly including conventional gears, planetary gears, worm gears, harmonic gears, and ball screws. Since the general requirements for servo reducers are a large reduction ratio and a small size, commonly used gear reducers and worm gear reducers are difficult to meet the requirements. Considering the structural dimensions of this solution, gear reducers and worm gear reducers require too much space, and the input and output shafts of the harmonic reduction transmission cannot be right angled. Therefore, this design adopts a ball screw transmission method. The controller has position protection logic to ensure that the current position angle of the rudder is within the preset standard deflection angle range, and the maximum deflection angle range should be greater than the standard deflection angle range. In a specific embodiment, the standard deflection angle range of the rudder is -20° to +20°, and the maximum deflection angle of the rudder is 23°.

[0034] Please refer to Figure 1 and Figure 5 The main control board also has a power management module, which is used to distribute power to supply power to the main control board and the servo motors respectively.

[0035] In practical implementation: such as Figure 5 The overall power management logic diagram of the system shows two isolated external input power supplies. One 28V power supply is used to drive the motor and peripheral devices, including powering the motor with 28V, converting 28V to 12V to power the PWM drive module (i.e., powering the drive circuit), and converting 12V to 5V to power the isolation module. The other 5V power supply is used to power the main control circuit, including powering the potentiometer with 5V, and converting 5V to 3.3V to power the main control circuit (i.e., powering the controller).

[0036] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, apparatus, article, or method that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, apparatus, article, or method. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, apparatus, article, or method that includes that element.

[0037] The above description is only a preferred embodiment of this application and does not limit the patent scope of this application. Any equivalent structural or procedural changes made based on the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A modular electric servo system, characterized in that, It includes a host computer, a power supply, a main control board and a servo motor. The main control board is equipped with a controller. The servo motor includes a drive board, a motor, a reducer, a servo plate and a potentiometer. The drive board is equipped with multiple drive circuits, an H-bridge circuit and a current sampling circuit. The drive board is electrically connected to the main control board, the motor, and the potentiometer, respectively. The host computer is communicatively connected to the main control board and is used to obtain the target location input by the user; The potentiometer is used to obtain the current position of the rudder plate; The current sampling circuit is used to collect the bus current of the motor; The controller includes multiple microprocessor units. The controller acquires the target position, the current position, and the bus current, and executes a fuzzy PID control algorithm through a preset algorithm structure, and generates a PWM wave with a corresponding duty cycle. The drive board controls the motor to rotate according to the PWM wave; The reducer includes an input end and an output shaft. The input end is connected to the motor, and the rudder is mounted on the output shaft. The reducer is used to change the speed and torque of the rudder, and the rudder is used to bear a preset load. The controller is also equipped with position protection logic and overcurrent protection logic to ensure that the rudder blades operate within a preset standard deflection angle range and that the motor temperature is within a safe temperature range.

2. The modular electric servo system according to claim 1, characterized in that, The controller is equipped with an analog-to-digital converter. The current position and the bus current are both analog voltage signals. The analog-to-digital converter is used to convert the analog voltage signals into discrete digital values ​​that the microprocessor unit can recognize and process.

3. The modular electric servo system according to claim 2, characterized in that, The algorithm structure includes a linear quadratic regulator, a fuzzy PID control module, and a PWM duty cycle module. The fuzzy PID control algorithm includes obtaining PID weights through the linear quadratic regulator based on the target position, the current position, and the bus current.

4. The modular electric servo system according to claim 3, characterized in that, The fuzzy PID control algorithm further includes: adjusting the preset initial control coefficients according to the PID weights by the fuzzy PID control module to obtain the optimal control coefficients, wherein the optimal control coefficients include proportional coefficients, integral coefficients and derivative coefficients.

5. The modular electric servo system according to claim 4, characterized in that, The fuzzy PID control algorithm further includes: generating a PWM wave with a corresponding duty cycle according to the optimal control coefficient through the PWM duty cycle module, and sending the PWM wave to the drive circuit.

6. The modular electric servo system according to claim 5, characterized in that, The driving circuit includes a driving chip and is used to amplify the power of the PWM wave.

7. The modular electric servo system according to claim 6, characterized in that, The H-bridge circuit is connected to the drive circuit and includes multiple power switches. The PWM wave controls the closing and opening of the power switches to control the operating state of the motor.

8. The modular electric servo system according to claim 1, characterized in that, The maximum deflection angle range of the rudder blade should be greater than the standard deflection angle range.

9. The modular electric servo system according to claim 1, characterized in that, The controller is electrically connected to the host computer via a preset communication bus and is used to receive the target position sent by the host computer in real time and send the current position of the rudder to the host computer.

10. The modular electric servo system according to claim 1, characterized in that, The main control board is also equipped with a power management module, which is used to distribute the power to supply power to the main control board and the servo motor respectively.

Images