Multi-axis servo time sequence control system based on real-time controller

Abstract

The invention discloses a multi-axis servo time sequence control system based on a real-time controller, which belongs to the technical field of motor control and realizes the effects of high precision, complex track and expandability through real-time interaction of a real-time controller module, a servo driver module, a sensor module, an upper computer, a multi-axis time sequence control module and a control panel. High-precision track control is carried out through the track control unit, the requirements for accuracy and smoothness in the machining and moving process are met, coordination and synchronization of the moving states of all the axis servo motors are achieved through the time sequence planning unit and the synchronous control unit, collision and interference among all the axis motors are avoided, and the machining precision is improved. And the system stability and reliability are enhanced.

Description

Technical Field

[0001] The present invention belongs to the technical field of motor control, and specifically relates to a multi-axis servo timing control system based on a real-time controller. Background Technique

[0002] The multi-axis servo control system is a technology commonly used to achieve multi-axis control and can accurately control the movement of multiple motor coordinate axes. The servo system is a control system that controls components in a closed-loop manner to complete desired position, speed, or torque commands. It mainly consists of a servo motor, a position sensor, a controller, and a motion control algorithm. The servo motor measures the position of the motor through a sensor and transmits the position signal back to the controller. The controller uses the position signal for calculation and then outputs a control voltage to control the movement of the motor.

[0003] The multi-axis servo control system mainly includes motor technology, control theory, and computer technology. Among them, motor technology is the foundation of the multi-axis servo control system, control theory is the core of the multi-axis servo control system, and computer technology is one of the key supporting technologies of the multi-axis servo control system. Before the 1960s, the multi-axis servo control system mainly used analog circuits to achieve control, and the motors used were stepper motors or DC motors, which had the disadvantages of low control accuracy and stability, complex mechanical structure, and large maintenance workload. From the 1960s to the 1980s, the multi-axis servo control system began to use digital circuits to achieve control, and the selection of motors also began to diversify, such as DC motors, stepper motors, and AC motors. After the 1980s, the multi-axis servo control system gradually developed towards the direction of intelligence, high precision, and high stability. So far, the multi-axis servo control system has been widely used in numerical control machine tools, robots, and the aerospace field.

[0004] For example, a Chinese patent with the authorization announcement number CN113311787B discloses a multi-axis servo control system, which includes a control main board, a PC, a teaching controller, and a servo driver; the PC, the teaching controller, and the servo driver are all in communication with the control main board; the control main board includes a control chip, a storage circuit, a first communication interface circuit, a servo control interface circuit, and an I / O interface circuit; at least 6 servo control interface circuits are configured, each servo control interface circuit is electrically connected to a servo driver respectively, and each servo driver is electrically connected to a servo motor of a driving axis respectively; the control chip runs a system program, and the system program at least includes: a data processing unit, a manual operation unit, at least two control units, a teaching unit, and a parameter editing unit.

[0005] As disclosed in a Chinese patent with the authorization announcement number CN108663993B, a multi-axis servo control system based on a real-time controller is provided. The motor is used to provide working power for a robot or a numerical control machine tool. The system further includes a servo driver, a real-time controller, and a host computer. The real-time controller is used to execute a control algorithm program to generate multi-axis motor control quantity information. The servo driver is used to drive the motor according to the multi-axis motor control quantity information to control the operation of the robot or the numerical control machine tool and feedback the actual position information. The host computer is used to display and save the multi-axis motor control quantity information of the real-time controller and the actual position information feedback by the servo driver. A multi-axis servo control system based on a real-time controller of the present invention can provide an open software development environment and rich hardware interfaces, and provide users with fast and convenient secondary development.

[0006] Through the analysis of the above prior art, it is found that the existing multi-axis servo control systems are vulnerable to the limitations of algorithms and parameters, making it difficult to achieve high-precision motion control, and prone to problems such as out-of-step and uncoordinated cooperation. For example, CN113311787B requires a stable power supply to ensure normal operation, is vulnerable to external signal interference, and has too high coupling between units. Once a unit needs to be upgraded or replaced, the entire system may need to be redesigned. In addition, the existing multi-axis servo control systems usually adopt a fixed hardware architecture, making it difficult to expand or adjust according to actual needs, unable to ensure real-time data transmission and control, which will lead to errors in motion control. For example, CN108663993B involves the collaborative work of multiple axes and multiple components, making the debugging of the system complex and time-consuming. To solve these problems, the present invention provides a multi-axis servo timing control system based on a real-time controller. By optimizing algorithms and parameter adjustment, the control precision is improved, fast response and collaborative control are achieved, the stability and efficiency of multi-axis collaborative work are improved, and at the same time, a unitized design is adopted, which has good scalability. Summary of the Invention

[0007] Aiming at the deficiencies of the prior art, the present invention proposes a multi-axis servo timing control system based on a real-time controller. The system conducts real-time interaction through a real-time controller module, a servo driver module, a sensor module, a host computer, a multi-axis timing control module, and a control board. High-precision trajectory control is achieved through a trajectory control unit, meeting the requirements of accuracy and smoothness during the processing and motion processes. The motion states of each axis servo motor are coordinated and synchronized through a timing planning unit and a synchronization control unit, avoiding collisions and interferences between the motors of each axis, and enhancing the stability and reliability of the system.

[0008] To achieve the above object, the present invention provides the following technical solutions:

[0009] A multi-axis servo timing control system based on a real-time controller, the system includes a real-time controller module, a servo driver module, a sensor module, a host computer, a multi-axis timing control module and a control board,

[0010] The real-time controller module is used to process input signals, execute control algorithm programs and generate control instructions to send to the servo motor;

[0011] The servo driver module is used to execute the instructions issued by the real-time controller, drive mechanical motion and feedback actual position information;

[0012] The sensor module is used to detect the state and position information of mechanical motion, and feedback the state and position information to the real-time controller module;

[0013] The host computer is used to display and save the multi-axis motor control quantity information of the real-time controller and the actual position information feedback by the servo driver, and provide a man-machine interaction interface;

[0014] The multi-axis timing control module is used to coordinate the motion and timing relationship between each axis;

[0015] The control board is used to coordinate and manage the communication and control processes between each module, and provide access to and control of underlying hardware resources.

[0016] Specifically, the real-time controller module includes a task scheduling unit, a communication unit and a trajectory control unit,

[0017] The task scheduling unit is used to manage the task scheduling of the servo control system;

[0018] The communication unit is used for data exchange and communication between the real-time controller and the servo motor, sensor and human-machine interface;

[0019] The trajectory control unit is used to receive control instructions, calculate the motion trajectories and states of the motors of each axis according to the preset trajectory algorithm and control logic, output corresponding control voltages, and at the same time, receive sensor signals and perform feedback control.

[0020] Specifically, the servo driver module includes a servo motor and a servo driver,

[0021] The servo motor is used to convert control instructions into rotational operations for mechanical motion;

[0022] The servo driver is used to receive control instructions, convert the received control instructions into switching signals for the inverter that controls the drive motor, and at the same time feedback the state information of the servo motor to the trajectory controller.

[0023] Specifically, the sensor module includes a sensor unit and a data processing unit,

[0024] The sensor unit is used to detect and collect system parameters during mechanical movement and feed back the collected system information to the servo driver;

[0025] The data processing unit is used to process the received sensor data and extract the state and position information of the mechanical movement.

[0026] Specifically, the multi-axis timing control module includes a timing planning unit and a synchronization control unit.

[0027] The timing planning unit is used to plan the timing relationship between axes according to the processing technology and movement requirements;

[0028] The synchronization control unit is used to control the movement synchronization between axes.

[0029] Specifically, the real-time controller module, the servo driver module, the sensor module, the upper computer, and the multi-axis timing control module all communicate with the control main board.

[0030] Specifically, the trajectory control unit adopts a trajectory optimization control strategy, and the specific steps include:

[0031] Step 101: Set the motion parameter data fed back by the sensor as The current system time is T, the initial position is x0, the initial velocity is v0, and the acceleration is a;

[0032] Step 102: Substitute the x0, v0, a into the formula to generate motion trajectory information. The formula is:

[0033]

[0034] e(t)=[[e x ′ ,1 (t);…;e x ′ ,i (t)],[e′ y,1 (t);…;e′ y,i (t)]],i=1,...,n

[0035]

[0036] where t represents the motion time, e x (t) represents the motion displacement error of the x-axis in the coordinate system, e y (t) represents the motion displacement error of the y-axis in the coordinate system, e′ x,1 (t) represents the column vector of the error of the first axis in the multi-axis control system in the motion displacement of the x-axis of the coordinate system, e′ y,1(t) represents the column vector of the error of the first axis in the multi-axis control system for the displacement of the y-axis in the coordinate system, e' x,i (t) represents the column vector of the error of the i-th axis in the multi-axis control system for the displacement of the x-axis in the coordinate system, e' y,i (t) represents the column vector of the error of the i-th axis in the multi-axis control system for the displacement of the y-axis in the coordinate system, n represents the number of axes of the multi-axis control system, e(t) represents the motion trajectory error, d(t) represents the motion trajectory information, λ p 、λ q 、λ m respectively represent the proportional coefficient, integral coefficient, and differential coefficient.

[0037] Specifically, the servo motor adopts a torque control strategy, and the specific steps include:

[0038] Step 201: Set the operating angular velocity of the motor as w, and the angular velocity of the motor obtained by the sensor is The moment of inertia is J;

[0039] Step 202: Calculate the multi-axis motor control quantity according to the torque equation during motor operation. The torque equation formula is:

[0040]

[0041] Among them, E represents the output torque, a w represents the angular acceleration, D represents the damping coefficient, and m represents the mass of the motor;

[0042] Step 203: Calculate the multi-axis motor control quantity according to the torque target value and the current motor state. The formula for the multi-axis motor control quantity is:

[0043]

[0044] Among them, Δu represents the multi-axis motor control quantity, represents the current in the motor obtained by the sensor, i x represents the current during motor operation, η represents the torque constant, p n represents the number of pole pairs;

[0045] Step 204: Input the calculated multi-axis motor control quantity into the servo driver to drive the motor to rotate, and monitor the actual output torque of the motor in real time through the motor encoder, and feedback the actual output torque to the real-time controller.

[0046] Specifically, the timing planning unit adopts an improved task scheduling strategy, and the specific steps include:

[0047] Step 301: Use the task scheduling algorithm to assign priorities to tasks according to the motion trajectory information, set the time slice length, put the tasks into the queue in the order of task priorities, and then take out the tasks one by one according to the queue order and execute one time slice. When a time slice is used up, the current task is suspended, and the system switches to the next task until all tasks are completed on time, obtaining the execution time and scheduling order of the tasks;

[0048] Step 302: According to the execution time and scheduling order of the tasks, calculate the timing parameter s = {T1, e x,y (t), φ x,y (t), v, a, E, E l} to determine the motion timing and time interval T1 of each axis, and adopt a closed-loop control strategy to compare the motion parameter data fed back by the sensor with the motion trajectory information d(t) to generate a control instruction. Among them, e x,y (t) represents the motion displacement error in the coordinate system, φ x,y (t) represents the motion phase difference in the coordinate system, E l represents the load torque. The specific formula for generating the control instruction is:

[0049]

[0050] e1(s) = r(s) - d(s), d(t) ∈ {d(s)}

[0051]

[0052] Among them, represents the column vector of the motion parameter data of the first to the i-th axes in the multi-axis control system in the x-axis in the data fed back by the sensor, represents the column vector of the motion parameter data of the first to the i-th axes in the multi-axis control system in the y-axis in the data fed back by the sensor, r(s) represents the column vector of the motion parameter data fed back by the sensor, e1(s) represents the error between the motion parameter data fed back by the sensor and the actual motion parameter data, d(s) represents the actual motion parameter data, and d1(s) represents the generated control instruction;

[0053] Step 303: According to the control instruction, perform coordinated control on each axis, monitor the state and parameter changes of the system in real time, and adjust the control instruction in a timely manner.

[0054] Specifically, the time compensation strategy adopted by the synchronization control unit includes the following specific steps:

[0055] Step 401: The synchronization control unit monitors the position and speed status information of each axis in real time and receives the timing parameter s = {T1, e x,y (t), φ x,y(t), v, a, E, E l};

[0056] Step 402: Compare the monitored status information with the motion timing parameters to determine whether there is a deviation. If there is a deviation, apply compensation and feedback the status information and real-time control instructions of the axis to the timing planning unit. The specific formula of the compensation strategy is:

[0057] Δt = K × (T1 - T)

[0058] where Δt represents the time compensation amount and K represents the time compensation coefficient.

[0059] Compared with the prior art, the beneficial effects of the present invention are:

[0060] 1. The present invention proposes a multi-axis servo timing control system based on a real-time controller, and optimizes and improves the architecture, operation steps and processes. The system has the advantages of simple process, low investment and operation costs, and low production cost, and improves the synchronization control accuracy on the basis of the original servo control system.

[0061] 2. The present invention proposes a multi-axis servo timing control system based on a real-time controller. According to the problems of non-synchronization and uncoordinated cooperation in the traditional servo control system, an optimized control strategy and a torque control strategy are adopted. Through high-speed calculation and precise control algorithms, high-precision position, speed and acceleration control can be achieved, and complex trajectory control can be realized, improving the positioning accuracy and stability of the system. Description of the Drawings

[0062] Figure 1 is the module structure diagram of a multi-axis servo timing control system based on a real-time controller of the present invention;

[0063] Figure 2 is the servo control strategy implementation model diagram of a multi-axis servo timing control system based on a real-time controller of the present invention;

[0064] Figure 3 is the flow chart of a multi-axis servo timing control system based on a real-time controller of the present invention. Detailed Embodiments

[0065] Embodiment 1

[0066] Please refer to Figure 1 , an embodiment provided by the present invention: A multi-axis servo timing control system based on a real-time controller, the system includes a real-time controller module, a servo driver module, a sensor module, a host computer, a multi-axis timing control module and a control board,

[0067] The real-time controller module, which is the core of the entire control system, is used to process input signals, execute control algorithm programs, and generate control instructions to send to the servo motor.

[0068] Servo usually refers to a servo system, which is an automatic control system that enables the output of the position, orientation, and state of an object to change arbitrarily following the input quantity.

[0069] The servo driver module, which is the bridge for achieving precise motion control, is used to execute the instructions issued by the real-time controller, drive mechanical motion, and feedback actual position information.

[0070] The sensor module is used to detect the state and position information of mechanical motion and feedback the state and position information to the real-time controller module.

[0071] The host computer is used to display and save the multi-axis motor control quantity information of the real-time controller and the actual position information feedback by the servo driver, and provide a human-machine interaction interface.

[0072] The multi-axis timing control module is used to coordinate the motion and timing relationship between axes.

[0073] The control board is used to coordinate and manage the communication and control processes between various modules, and provide access to and control of underlying hardware resources.

[0074] For a multi-axis servo timing control system based on a real-time controller, the inputs include control instructions, motion parameters, and sensor signals, and the outputs are the motion trajectories and states of the motors of each axis. The main idea of the present invention is: by receiving control instructions and motion parameters, calculating the motion trajectories and states of the motors of each axis in real time, and outputting corresponding control voltages to drive the motors to move. At the same time, the system also obtains the position, speed, and acceleration parameters of the motors of each axis through sensor signals for feedback control, further optimizing the motion trajectories and states of the motors, so as to achieve the effects of improving the coordination and stability of multi-axis motion, improving the accuracy and repeatability of multi-axis motion, reducing motion errors, shortening the production cycle, improving production efficiency, enhancing the reliability and stability of multi-axis motion, and reducing failure rates and maintenance costs.

[0075] The real-time controller module includes a task scheduling unit, a communication unit, and a trajectory control unit.

[0076] The task scheduling unit is used to manage the task scheduling of the servo control system.

[0077] The communication unit is used for data exchange and communication between the real-time controller and the servo motor, sensor, and human-machine interface.

[0078] The trajectory control unit is used to receive control instructions, calculate the motion trajectories and states of the motors of each axis according to a preset trajectory algorithm and control logic, output corresponding control voltages, and at the same time, receive sensor signals and perform feedback control. These instructions usually include three modes: position, speed, and torque.

[0079] The servo drive module includes a servo motor and a servo drive.

[0080] The servo motor is used to convert control instructions into rotational operations for mechanical motion.

[0081] The motor control algorithm is the core part of the servo drive module, which is used to achieve the speed and position control of the motor. According to the control instructions issued by the real-time controller module, the motor control algorithm calculates the input voltage or current of the motor to drive the motor to move according to the instruction requirements.

[0082] The servo drive is used to receive control instructions, convert the received control instructions into switching signals for controlling the inverter of the drive motor, and at the same time feedback the status information of the servo motor to the trajectory controller.

[0083] The process of the servo drive converting control instructions into voltage and current signals usually involves the following steps:

[0084] (1) The servo drive module receives control instructions from the real-time controller module and decodes them to understand the desired motion parameters.

[0085] (2) The drive calculates and outputs a current signal. By adjusting the input voltage or current of the motor, the motor can generate the required torque or torque. Among them, calculating the current signal for the decoded control instructions is mainly achieved by calculating the duty cycle of Pulse Width Modulation (PWM). The specific formula is:

[0086]

[0087] Among them, T2 represents the PWM period, and Δu represents the multi-axis motor control amount.

[0088] (3) The servo drive adjusts the input voltage or current of the motor according to the difference between the current speed and the desired speed of the motor.

[0089] (4) The servo drive adjusts the input voltage or current of the motor according to the difference value e(t) between the current position and the desired position of the motor. Through position loop control, it ensures that the motor accurately tracks the desired motion trajectory.

[0090] The sensor module includes a sensor unit and a data processing unit.

[0091] The sensor unit is used to detect and collect system parameters during mechanical motion and feed back the collected system information to the servo driver;

[0092] The data processing unit is used to process the received sensor data and extract the state and position information of the mechanical motion.

[0093] The multi-axis timing control module includes a timing planning unit and a synchronization control unit,

[0094] The timing planning unit is used to plan the timing relationship between axes according to the processing technology and motion requirements;

[0095] The synchronization control unit is used to control the motion synchronization between axes.

[0096] The real-time controller module, the servo driver module, the sensor module, the host computer, and the multi-axis timing control module all communicate with the control main board.

[0097] The specific working processes of the corresponding units in the real-time controller module, the servo driver module, the sensor module, and the multi-axis timing control module include:

[0098] The real-time controller module receives the feedback data from the sensor module and sends control instructions to the servo driver module. The multi-axis timing control module coordinates the motion and timing relationship of each axis according to the system requirements and the preset timing relationship;

[0099] The sensor module collects various parameters of the system through the sensor unit and transmits the collected parameter data to the data processing unit; the data processing unit uses the Kalman filtering method to filter and process the received parameter data, extracts the state and position information of the mechanical motion, and feeds back the extracted state and position information of the mechanical motion to the real-time controller module;

[0100] The real-time controller module uses the task scheduling unit to assign priorities, time limits, and dependencies to each task; according to the priority, time limit, and dependency factors of each task, it uses a priority-based scheduling algorithm to schedule and manage the tasks, and according to the scheduling results, assigns system resources to each task and executes them; the communication unit receives the resource information and execution control instructions from the task scheduling unit, parses and processes them, and at the same time sends the state and control instructions of the real-time controller module to the trajectory control unit; the trajectory control unit receives the control instructions transmitted by the communication unit, uses the target trajectory and control algorithm for trajectory tracking and closed-loop control, and feeds back the actual position information and state to the task scheduling unit;

[0101] Before the real-time controller module operates, it is necessary to clean and check the rationality of the parameter data sent by the received sensors, remove outliers and unreasonable data, and ensure the accuracy and reliability of the input data.

[0102] In a multi-axis servo timing control system based on a real-time controller, a task usually refers to a series of operations or actions that the system needs to complete. These tasks include:

[0103] (1) Motion trajectory planning task: According to the process requirements and motion parameters of the system, calculate and plan the motion trajectories of each axis. This involves determining the starting point, ending point, speed, and acceleration parameters to ensure that the axis can move precisely according to the set trajectory. Among them, the process requirements include: processing flow, accuracy requirements, task priority, and safety standards. The motion parameters include: trajectory planning, speed and acceleration control, position control, synchronization, and coordination;

[0104] (2) Real-time control task: According to the instructions of the task scheduling unit and the feedback data of the sensor module, calculate and send control instructions to the servo drive module in real time to drive the motor to move precisely. The task involves closed-loop control algorithms to achieve fast and accurate motion control;

[0105] (3) Data processing and analysis task: Filter, process, and analyze the data collected by the sensor module to extract useful information or calculate specific parameters;

[0106] (4) Synchronous control task: According to the timing parameters calculated by the timing planning unit, coordinate and control each axis to ensure that they move according to the set timing, involving synchronous precision control between multiple axes, and a closed-loop synchronous control algorithm needs to be implemented;

[0107] (5) System status monitoring and exception handling task: Real-time monitor the status parameters of the system and the working status of each module, detect abnormal situations or faults, and once an abnormality or fault is detected, take protective measures such as alarming and stopping to ensure the safety and stability of the system.

[0108] The servo drive module receives the control instructions from the real-time controller module and converts the control instructions into voltage and current signals; the servo motor generates torque and speed according to the received voltage and current signals, and feeds back the actual position and speed to the servo drive; the servo drive compares the received feedback information of the position and speed with the control instructions, sends the comparison result to the servo motor, and the servo motor adjusts according to the received result;

[0109] The multi-axis timing control module calculates the motion timing of each axis through the timing planning unit, that is, the motion start point, end point, speed, and acceleration parameters of each axis, and sends the calculated motion timing parameters to the synchronization control unit; after receiving the motion timing parameters, the synchronization control unit monitors the position and speed status information of each axis in real time, and determines whether the status information is consistent with the motion timing parameters. If not, there is a deviation, and the synchronization control unit applies compensation; the synchronization control unit feeds back the axis status information and real-time control instructions to the timing planning unit, and the timing planning unit makes real-time adjustments and optimizations based on the feedback information.

[0110] Embodiment 2

[0111] Please refer to Figures 2 - 3 , another embodiment provided by the present invention: a multi-axis servo timing control system based on a real-time controller, including:

[0112] The trajectory control unit adopts a trajectory optimization control strategy, and the specific steps include:

[0113] Step 101: Set the motion parameter data fed back by the sensor as The current time of the system is T, the initial position is x0, the initial velocity is v0, and the acceleration is a;

[0114] Step 102: Substitute the x0, v0, a into the formula to generate motion trajectory information, and the formula is:

[0115]

[0116] e(t)=[[e x ′ ,1 (t);…;e x ′ ,i (t)],[e′ y,1 (t);…;e′ y,i (t)]],i=1,...,n

[0117]

[0118] where t represents the motion time, e x (t) represents the motion displacement error of the x-axis in the coordinate system, e y (t) represents the motion displacement error of the y-axis in the coordinate system, e x ′ ,1 (t) represents the column vector of the error of the first axis in the multi-axis control system in the motion displacement of the x-axis in the coordinate system, e′ y,1 (t) represents the column vector of the error of the first axis in the multi-axis control system in the motion displacement of the y-axis in the coordinate system, e x ′ ,i(t) represents the column vector of the error of the i-th axis in the multi-axis control system for the displacement of the x-axis of the coordinate system, e′ y,i (t) represents the column vector of the error of the i-th axis in the multi-axis control system for the displacement of the y-axis of the coordinate system, n represents the number of axes of the multi-axis control system, e(t) represents the motion trajectory error, d(t) represents the motion trajectory information, λ p 、λ q 、λ m respectively represent the proportional coefficient, integral coefficient, and differential coefficient.

[0119] The servo motor adopts a torque control strategy, and the specific steps include:

[0120] Step 201: Set the operating angular velocity of the motor to w, and the angular velocity of the motor obtained by the sensor is The moment of inertia is J;

[0121] Step 202: Calculate the multi-axis motor control quantity according to the torque equation during motor operation. The torque equation formula is:

[0122]

[0123] where E represents the output torque, a w represents the angular acceleration, D represents the damping coefficient, and m represents the mass of the motor;

[0124] Step 203: Calculate the multi-axis motor control quantity according to the torque target value and the current motor state. The formula for calculating the multi-axis motor control quantity is:

[0125]

[0126] where Δu represents the multi-axis motor control quantity, represents the current in the motor obtained by the sensor, i x represents the operating current of the motor, η represents the torque constant, p n represents the number of pole pairs;

[0127] Step 204: Input the calculated multi-axis motor control quantity into the servo driver to drive the motor to rotate. The actual output torque of the motor is monitored in real time through the motor encoder, and the actual output torque is fed back to the real-time controller.

[0128] The timing planning unit adopts an improved task scheduling strategy, and the specific steps include:

[0129] Step 301: Use the task scheduling algorithm to assign priorities to tasks according to the motion trajectory information, set the time slice length, put the tasks into the queue according to the priority order of the tasks, and then take out the tasks one by one according to the queue order and execute one time slice. When a time slice is used up, the current task is suspended, and the system switches to the next task until all tasks are completed on time, obtaining the execution time and scheduling order of the tasks;

[0130] Specifically, set the task set B = {t1, t2,..., t n}, the priority of each task is g(t i ), the completed task set is A, and the to-be-completed task set U = B - A. Select the task with the highest priority from the to-be-completed task set U as t i . If the start time δ(t i ) of task t i is greater than or equal to the current time t, then execute task t i , and remove t i from the to-be-completed task set U. Repeat the above steps until the to-be-completed task set U is empty.

[0131] Among them, the time slice is the time period allocated for each task to execute. A too long time slice will cause the high-priority tasks to wait too long, and a too short time slice will cause frequent task switching, reducing the system efficiency. The present invention selects the longest task first method to achieve the effect of minimizing the total execution time of tasks.

[0132] Step 302: According to the execution time and scheduling order of the tasks, calculate the timing parameters s = {T1, e x,y (t), φ x,y (t), v, a, E, E l} to determine the motion timing and time interval T1 of each axis, and adopt a closed-loop control strategy to compare the motion parameter data fed back by the sensor with the motion trajectory information d(t) to generate a control instruction. Among them, e x,y (t) represents the motion displacement error in the coordinate system, φ x,y (t) represents the motion phase difference in the coordinate system, and E l represents the load torque. The specific formula for generating the control instruction is:

[0133]

[0134] e1(s) = r(s) - d(s), d(t) ∈ {d(s)}

[0135]

[0136] Among them, It represents the column vector of the motion parameter data of the 1st to the i-th axes in the multi-axis control system on the x-axis in the data fed back by the sensor. It represents the column vector of the motion parameter data of the 1st to the i-th axes in the multi-axis control system on the y-axis in the data fed back by the sensor. r(s) represents the column vector of the motion parameter data fed back by the sensor, e1(s) represents the error between the motion parameter data fed back by the sensor and the actual motion parameter data, d(s) represents the actual motion parameter data, and d1(s) represents the generated control instruction.

[0137] Step 303: According to the control instruction, perform coordinated control on each axis, monitor the state and parameter changes of the system in real time, and adjust the control instruction in a timely manner.

[0138] The synchronization control unit adopts a time compensation strategy, and the specific steps include:

[0139] Step 401: The synchronization control unit monitors the position and speed status information of each axis in real time, and receives the timing parameter s = {T1, e x,y (t), φ x,y (t), v, a, E, E l} sent in Step 202.

[0140] Step 402: Compare the monitored status information with the motion timing parameter to determine whether there is a deviation. If there is a deviation, apply compensation, and feedback the status information of the axis and the real-time control instruction to the timing planning unit. The specific formula of the compensation strategy is:

[0141] Δt = K × (T1 - T)

[0142] Where, Δt represents the time compensation amount, and K represents the time compensation coefficient.

[0143] Applying compensation usually means correcting or adjusting the motion timing parameter according to the deviation situation to correct the deviation and make the actual motion state of the axis consistent with the preset motion timing parameter. The purpose of compensation is to improve the stability and accuracy of the system and ensure that the multi-axis servo system can perform coordinated motion according to the expected timing relationship. The present invention selects a time compensation strategy and adjusts the time interval and time offset parameter according to the deviation situation to achieve time synchronization control.

[0144] The embodiments of the present invention have been described above in conjunction with the accompanying drawings. However, the present invention is not limited to the above specific embodiments. The above specific embodiments are merely illustrative and not restrictive. Under the inspiration of the present invention, those of ordinary skill in the art can also make changes, modifications, substitutions, and variations to the above embodiments without departing from the spirit and scope protected by the present invention and the claims. These all fall within the protection scope of the present invention.

Claims

1. A multi-axis servo timing control system based on a real-time controller, characterized in that: Including real-time controller module, servo drive module, sensor module, host computer, multi-axis timing control module and control board, The real-time controller module is used to process input signals, execute control algorithm programs and generate control instructions to send to the servo motor; The servo drive module is used to execute the instructions issued by the real-time controller, drive the mechanical movement and feedback the actual position information; The sensor module is used to detect the state and position information of the mechanical movement and feed back the state and position information to the real-time controller module; The host computer is used to display and save the multi-axis motor control quantity information of the real-time controller and the actual position information fed back by the servo driver, and provide a human-computer interaction interface; The multi-axis timing control module is used to coordinate the motion and timing relationship between the axes; The control panel is used to coordinate and manage the communication and control processes between various modules and provide access to and control of underlying hardware resources.

2. A multi-axis servo timing control system based on a real-time controller as claimed in claim 1, characterized in that: The real-time controller module includes a task scheduling unit, a communication unit and a trajectory control unit. The task scheduling unit is used to manage the task scheduling of the servo control system; The communication unit is used for data exchange and communication between the real-time controller and the servo motor, sensor and human-machine interface; The trajectory control unit is used to receive control instructions, calculate the motion trajectory and state of each axis motor according to a preset trajectory algorithm and control logic, output corresponding control voltage, and at the same time, receive sensor signals and perform feedback control.

3. A multi-axis servo timing control system based on a real-time controller as claimed in claim 2, characterized in that: The servo drive module includes a servo motor and a servo drive. The servo motor is used to convert the control instruction into a rotation operation to perform mechanical movement; The servo driver is used to receive control instructions, convert the received control instructions into switching signals of the inverter that controls the drive motor, and feed back the state information of the servo motor to the trajectory controller.

4. A multi-axis servo timing control system based on a real-time controller as claimed in claim 3, characterized in that: The sensor module includes a sensor unit and a data processing unit. The sensor unit is used to detect and collect system parameters during mechanical movement, and feed back the collected system information to the servo driver; The data processing unit is used to process the received sensor data and extract the state and position information of the mechanical movement.

5. A multi-axis servo timing control system based on a real-time controller as claimed in claim 4, characterized in that: The multi-axis timing control module includes a timing planning unit and a synchronization control unit. The timing planning unit is used to plan the timing relationship between the axes according to the processing technology and motion requirements; The synchronization control unit is used to control the movement synchronization between the axes.

6. A multi-axis servo timing control system based on a real-time controller as claimed in claim 5, characterized in that: The real-time controller module, servo drive module, sensor module, host computer and multi-axis timing control module all communicate with the control mainboard.

7. A multi-axis servo timing control system based on a real-time controller as claimed in claim 6, characterized in that: The trajectory control unit adopts a trajectory optimization control strategy, and the specific steps include: Step 101: Set the motion parameter data fed back by the sensor to The current time of the system is T, the initial position is x0, the initial velocity is v0, and the acceleration is a; Step 102: Substitute x0, v0, and a into the formula to generate motion trajectory information. The formula is: e(t)=[[e′ x,1 (t);…;e′ x,i (t)],[e′ y,1 (t);…;e′ y,i (t)]],i=1,...,n Among them, t represents the movement time, e x (t) represents the x-axis motion displacement error in the coordinate system, e y (t) represents the displacement error of the y-axis motion in the coordinate system, e′ x,1 (t) represents the column vector of the first axis error of the multi-axis control system in the x-axis motion displacement of the coordinate system, e′ y,1 (t) represents the column vector of the first axis error of the multi-axis control system in the y-axis motion displacement of the coordinate system, e′ x,i (t) represents the column vector of the i-th axis error of the multi-axis control system in the x-axis motion displacement of the coordinate system, e′ y,i (t) represents the column vector of the i-th axis error of the multi-axis control system in the y-axis motion displacement of the coordinate system, n represents the number of axes of the multi-axis control system, e(t) represents the motion trajectory error, d(t) represents the motion trajectory information, and λ p , q , m They represent the proportional coefficient, integral coefficient, and differential coefficient respectively.

8. A multi-axis servo timing control system based on a real-time controller as claimed in claim 7, characterized in that: The servo motor adopts a torque control strategy, and the specific steps include: Step 201: Set the motor running angular velocity to w, and the motor angular velocity obtained by the sensor is The moment of inertia is J; Step 202: Calculate the multi-axis motor control quantity according to the torque equation when the motor is running. The torque equation formula is: Where, E represents the output torque, a w represents angular acceleration, D represents damping coefficient, and m represents motor mass; Step 203: Calculate the multi-axis motor control quantity according to the torque target value and the current motor state. The calculation formula of the multi-axis motor control quantity is: Among them, Δu represents the multi-axis motor control quantity, Represents the current in the motor obtained by the sensor, i x represents the current when the motor is running, η represents the torque constant, and p n represents the number of pole pairs; Step 204: input the calculated multi-axis motor control quantity into the servo driver to drive the motor to rotate, monitor the actual output torque of the motor in real time through the motor encoder, and feed back the actual output torque to the real-time controller.

9. A multi-axis servo timing control system based on a real-time controller as claimed in claim 8, characterized in that: The timing planning unit adopts an improved task scheduling strategy, and the specific steps include: Step 301: Use the task scheduling algorithm to assign the priority of the task according to the motion trajectory information, set the time slice length, put the task into the queue according to the priority order of the task, and then take out the tasks one by one according to the queue order and execute a time slice. When a time slice is used up, the current task is suspended and the system goes to the next task until all tasks are completed on time, and the execution time and scheduling order of the tasks are obtained; Step 302: Calculate the timing parameter s={T1,e x,y (t),φ x,y (t),v,a,E,E l }, determine the motion sequence and time interval T1 of each axis, and adopt a closed-loop control strategy to compare the motion parameter data fed back by the sensor with the motion trajectory information d(t) to generate control instructions, where e x,y (t) represents the motion displacement error in the coordinate system, φ x,y (t) represents the phase difference of motion in the coordinate system, E l Represents the load torque and generates the specific formula for the control command: e1(s)=r(s)-d(s),d(t)∈{d(s)} in, Represents the column vector of the motion parameter data of the 1st to ith axes of the multi-axis control system in the x-axis in the sensor feedback data, represents the column vector of the motion parameter data of the 1st to the i-th axis of the multi-axis control system in the y-axis in the data fed back by the sensor, r(s) represents the column vector of the motion parameter data fed back by the sensor, e1(s) represents the error between the motion parameter data fed back by the sensor and the actual motion parameter data, d(s) represents the actual motion parameter data, and d1(s) represents the generated control instruction; Step 303: According to the control instructions, coordinate and control each axis, monitor the system status and parameter changes in real time, and adjust the control instructions in time.

10. A multi-axis servo timing control system based on a real-time controller as claimed in claim 9, characterized in that: The time compensation strategy adopted by the synchronization control unit specifically includes the following steps: Step 401: The synchronous control unit monitors the position and speed status information of each axis in real time, and receives the timing parameter s={T1,e x,y (t),φ x,y (t),v,a,E,E l }; Step 402: Compare the monitored state information with the motion timing parameters to determine whether there is a deviation. If there is a deviation, apply compensation and feed back the state information of the axis and the real-time control instructions to the timing planning unit. The specific formula of the compensation strategy is: Δt=K×(T1-T) Wherein, Δt represents the time compensation amount, and K represents the time compensation coefficient.

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