Electric cylinder used for robot articulated arm and control system

Abstract

The invention provides an electric cylinder used for a robot articulated arm and a control system, and relates to the technical field of robots. The state analysis unit is used for receiving the actual working state data of the electric cylinder, performing state analysis on the actual working state data of the electric cylinder, and analyzing the difference between the actual working state data and the control parameter of the electric cylinder in the task instruction to obtain a state evaluation value corresponding to the parameter; and comparing the state evaluation value with a threshold value to obtain an adjustment signaling corresponding to the parameter, and calculating a control signal of the servo motor. According to the control system, actual working state data of the electric cylinder are accurately obtained through the sensing acquisition module, control parameters are accurately analyzed through the instruction analysis unit, a control signal is obtained through the state analysis unit according to difference calculation and a PID algorithm, and high-precision control over displacement, speed and thrust of the electric cylinder is ensured through weighted processing optimization; and the joint movement accuracy and the operation precision of the robot are guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of robots, and particularly to an electric cylinder and a control system for a robot joint arm. Background Art

[0002] In the process of modern industrial automation, robot joint arms are increasingly widely used, and the key to improving their performance lies in the optimization of joint drive components and control systems. Traditional electric cylinders mostly use belt drive to drive robot joints. Although power transmission is achieved to a certain extent, there are many drawbacks. Belt drive is prone to problems such as slipping and elastic deformation, resulting in low transmission efficiency and serious energy loss. More critically, the upper limit of the thrust it can provide is relatively small, making it difficult to meet the operating requirements of robots under high-load conditions, such as heavy machinery processing, large material handling and other scenarios, severely restricting the application range and working efficiency of robots.

[0003] At the same time, the existing control systems often have poor compatibility with electric cylinders and cannot fully utilize the mechanical performance advantages of electric cylinders. In terms of control accuracy, it is difficult to achieve high-precision control of the displacement, speed and thrust of electric cylinders, resulting in poor accuracy of robot joint movement and affecting the operation accuracy. In terms of response speed, in the face of complex and changing work tasks, the slow response of the control system cannot timely adjust the working state of the electric cylinder, reducing the overall working efficiency and dynamic performance of the robot. Therefore, it is necessary to provide an electric cylinder and a control system for a robot joint arm to solve the above technical problems. Summary of the Invention

[0004] The present invention provides an electric cylinder for a robot joint arm, which solves the problems raised in the above background art.

[0005] To solve the above technical problems, an electric cylinder for a robot joint arm provided by the present invention includes a gearbox. One side of the top surface of the gearbox is fixedly installed with a bearing seat through screws. A servo motor is provided on one side of the bearing seat, and the servo motor is fixedly installed on the top surface of the gearbox through screws. A telescopic box is fixedly installed on the top surface of the bearing seat, and a sealing cover is fixedly installed on the top surface of the telescopic box. A transmission component is provided in the gearbox, and a telescopic component is provided in the telescopic box.

[0006] Preferably, the transmission component includes a gearbox, which is composed of a box body and a top plate. One side of the bottom surface of the top plate is rotatably connected with a driving gear. A speed-changing gear is provided on one side of the driving gear, and the speed-changing gear is rotatably connected to the middle of the bottom surface of the top plate. The speed-changing gear has upper and lower layers. The upper layer of the speed-changing gear is in abutting cooperation with the driving gear, and one side of the lower layer of the speed-changing gear is in abutting cooperation with a driven gear, and the driven gear is rotatably connected to the bottom surface of the top plate.

[0007] Preferably, the top surfaces of the driving gear and the driven gear penetrate through the top plate and are respectively connected to a servo motor and a bearing seat. A bearing is provided at the center inside the bearing seat, a rotating shaft is provided inside the bearing, the lower end of the rotating shaft is fixedly connected to the driven gear, and the upper end of the rotating shaft is fixedly connected to a threaded rod.

[0008] Preferably, the telescopic assembly includes a threaded rod. External threads are provided on the outer side surface of the threaded rod, a threaded sleeve is arranged in cooperation with the external threads on the threaded rod, splines are fixedly connected to the left and right sides of the outer side surface of the threaded sleeve, spline grooves are provided on the inner side surface of the telescopic box in cooperation with the splines, and a telescopic tube is fixedly connected to the top surface of the threaded sleeve.

[0009] Preferably, the top end of the telescopic tube penetrates through the sealing cover and is fixedly connected to a connecting block, and a sealing ring is provided at the abutting position of the sealing cover and the telescopic tube.

[0010] Preferably, a stabilizing seat is rotatably connected to the middle of the bottom surface of the driven gear, and the stabilizing seat is fixedly connected to the inner bottom surface of the gear box.

[0011] A control system of an electric cylinder used for a robotic joint arm proposed by the present invention, the control system includes a sensing and acquisition module, a controller, and a driver; The sensing and acquisition module is used to collect the actual working state data of the electric cylinder in real time and transmit it to the controller; The controller includes an instruction parsing unit, a state analysis unit, a fault diagnosis unit, a communication management unit, and a parameter storage unit; The instruction parsing unit is used to receive a task instruction from a host computer and parse out the control parameters of the electric cylinder from the task instruction, including target displacement, target speed, and target thrust; The state analysis unit is used to receive the actual working state data of the electric cylinder, perform state analysis on the actual working state data of the electric cylinder, analyze the difference between the actual working state data and the control parameters of the electric cylinder in the task instruction to obtain a state evaluation value corresponding to the parameter, compare the state evaluation value with its threshold value to obtain an adjustment signal corresponding to the parameter, and calculate the control signal of the servo motor; The fault diagnosis unit is used to receive the state evaluation value corresponding to the parameter, set the fault diagnosis threshold corresponding to the parameter in the control parameter. If the state evaluation value is greater than its fault diagnosis threshold, a state fault signal corresponding to the state evaluation value is generated; the state fault signal and the corresponding parameter, generation time, state evaluation value, number of the electric cylinder, and position are marked as fault information; The parameter storage unit is used to store various parameters of the system, and the various parameters include mechanical parameters, control parameters of the electric cylinder, state evaluation values of the parameters, and fault diagnosis thresholds; The communication management unit is used to coordinate the communication between the controller, the driver and each module; The driver is used to convert the control signal calculated by the controller into a three-phase AC voltage using space vector pulse width modulation technology and apply it to the servo motor when receiving the adjustment signaling of the parameter, so as to drive the output shaft of the servo motor to rotate, drive the gearbox transmission assembly to operate, and then drive the telescopic assembly to achieve telescopic movement.

[0012] Preferably, the specific operation mechanism of the state analysis unit is as follows: Obtain the actual working state data of the electric cylinder sent by the sensing and acquisition module, including actual displacement, actual speed and actual torque; calculate the difference between the parameters in the actual working state data of the electric cylinder and the corresponding parameters of the control parameters in its task instruction to obtain the target deviation value corresponding to the parameter. Calculate the control signal of the servo motor using a control algorithm. Perform weighted processing on all the control signals in the servo motor control parameters to obtain the relevant adjustment factor corresponding to the parameter; use the relevant adjustment factor corresponding to the parameter to adjust and update the control signal of the servo motor. Mark the time region between the starting moment of the electric cylinder and the current moment as the dynamic monitoring time zone. Obtain the target deviation value of the parameter in the control parameter at any acquisition moment within the dynamic monitoring time zone, and calculate the statistical indicators of the target deviation value of the parameter within the dynamic monitoring time zone, including maximum value, minimum value, average value, and standard deviation; perform weighted calculation on the target deviation value at the current moment with all the indicators in its statistical indicators to obtain the state evaluation value of the parameter; set the evaluation threshold of any parameter in the control parameter. If the state evaluation value is greater than its evaluation threshold, it means that the parameter corresponding to the state evaluation value has a deviation, and generate the adjustment signaling corresponding to the parameter.

[0013] Preferably, the specific operation mechanism of the communication management unit is: used to regularly send data requests to the sensor using the industrial communication protocol and receive the data response sent by the sensor. The actual working state data of the electric cylinder is composed of the data responses of all sensors; it is also used to receive the task instruction of the upper computer through the Ethernet protocol and upload the actual working state data and fault information of the electric cylinder to the upper computer; it is also used to send the control signal calculated by the controller to the driver using the space vector pulse width modulation protocol.

[0014] Preferably, the sensing and acquisition module includes a displacement sensor, a torque sensor and a speed sensor. The displacement sensor is a linear variable differential transformer installed at the telescopic part of the electric cylinder to measure the telescopic displacement of the electric cylinder, marked as the actual displacement; the torque sensor is installed on the power transmission path of the electric cylinder to measure the output torque of the electric cylinder, marked as the actual torque; the speed sensor is used to detect the magnetic field change frequency of the rotating component, and according to the calculation formula, the linear velocity is obtained by multiplying the radius of the rotating component by the angular velocity, and the movement speed of the electric cylinder is calculated and marked as the actual speed; the actual displacement, actual speed, and actual torque of the electric cylinder are marked as the actual working state data of the electric cylinder.

[0015] Compared with the related technology, the electric cylinder used in the robot joint arm provided by the present invention has the following beneficial effects: 1. The mechanical structure composed of a gearbox, a servo motor, a telescopic assembly, etc. is adopted in the present invention, abandoning the traditional belt drive, effectively avoiding slipping and elastic deformation, significantly improving the transmission efficiency, reducing energy loss, and greatly enhancing the thrust, which can better meet the high-load operation requirements and expand the application range and working efficiency of the robot.

[0016] 2. The control system of the present invention accurately obtains the actual working state data of the electric cylinder through the sensing and acquisition module, the command parsing unit accurately parses the control parameters, the state analysis unit obtains the control signal according to the difference calculation and the PID algorithm, and optimizes it through weighted processing to ensure the high-precision control of the displacement, speed, and thrust of the electric cylinder, and guarantee the accuracy of the robot joint movement and the operation accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic structural diagram of the electric cylinder used in the robot joint arm provided by the present invention; Figure 1 It is a schematic overall appearance diagram of the electric cylinder used in the robot joint arm proposed by the present invention; Figure 2 It is a front view schematic of the overall appearance proposed by the present invention; Figure 3 It is a top view schematic of the overall appearance proposed by the present invention; Figure 4 It is a three-dimensional schematic diagram of the structure of the transmission component proposed by the present invention; Figure 5 It is a partial structural schematic diagram of the transmission component proposed by the present invention; Figure 6 It is a principle block diagram of the control system of the electric cylinder used in the robot joint arm proposed by the present invention.

[0018] Reference numerals in the figure: 1, gearbox; 2, bearing seat; 3, servo motor; 4, telescopic box; 5, sealing cover; 6, driving gear; 7, speed-changing gear; 8, driven gear; 9, threaded rod; 10, threaded sleeve; 11, telescopic tube; 12, bearing; 13, stabilizing seat. Detailed implementation manners

[0019] 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.

[0020] The terms used in this disclosure are for the purpose of describing specific embodiments only and are not intended to limit the disclosure. The singular forms "a set", "a class" and "the" used in this disclosure and the appended claims are also intended to include the plural forms unless the context clearly dictates otherwise. It should also be understood that the term "and / or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

[0021] It should be understood that although the terms first, second, third, etc. may be used in this disclosure to describe various information, such information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of this disclosure, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the word "if" as used herein may be interpreted as "when" or "while" or "in response to determining".

[0022] Please refer to Figures 1 - 6. An electric cylinder used in a robotic joint arm, comprising a gearbox 1. On one side of the top surface of the gearbox 1, a bearing seat 2 is fixedly installed by screws. On one side of the bearing seat 2, there is a servo motor 3, and the servo motor 3 is fixedly installed on the top surface of the gearbox 1 by screws. On the top surface of the bearing seat 2, a telescopic box 4 is fixedly installed. On the top surface of the telescopic box 4, a sealing cover 5 is fixedly installed. A transmission component is arranged inside the gearbox 1, and a telescopic component is arranged inside the telescopic box 4. The modular design facilitates assembling and upgrading the equipment according to requirements; The transmission component includes the gearbox 1. The gearbox 1 is composed of a box body and a top plate. On one side of the bottom surface of the top plate, a driving gear 6 is rotatably connected. On one side of the driving gear 6, there is a speed-changing gear 7, and the speed-changing gear 7 is rotatably connected to the middle of the bottom surface of the top plate. The speed-changing gear 7 has two upper and lower layers. The upper layer of the speed-changing gear 7 is in mating contact with the driving gear 6, and on one side of the lower layer of the speed-changing gear 7, there is a driven gear 8 in mating contact. The driven gear 8 is rotatably connected to the bottom surface of the top plate. The cooperation of the driving gear 6, the speed-changing gear 7, and the driven gear 8 facilitates reducing the torque of the transmission; The top surfaces of the driving gear 6 and the driven gear 8 both penetrate the top plate and are respectively connected to the servo motor 3 and the bearing seat 2. In the center of the interior of the bearing seat 2, there is a bearing 12. Inside the bearing 12, there is a rotating shaft. The lower end of the rotating shaft is fixedly connected to the driven gear 8, and the upper end of the rotating shaft is fixedly connected to a threaded rod 9. Through the cooperation of the bearing seat 2 and the rotating shaft, it is convenient to connect different gearboxes 1 and telescopic boxes 4.

[0023] In the present invention, the telescopic component includes the threaded rod 9. An external thread is provided on the outer side surface of the threaded rod 9. A threaded sleeve 10 is arranged in cooperation with the external thread surface of the threaded rod 9. On both the left and right sides of the outer side surface of the threaded sleeve 10, splines are fixedly connected. Spline grooves are provided on the inner side surface of the telescopic box 4 in cooperation with the splines. A telescopic tube 11 is fixedly connected to the top surface of the threaded sleeve 10. Through the cooperation of the threaded rod 9 and the threaded sleeve 10, it is convenient to drive the telescopic tube 11 to move; The top end of the telescopic tube 11 penetrates the sealing cover 5 and is fixedly connected to a connecting block. A sealing ring is provided at the abutting position of the sealing cover 5 and the telescopic tube 11. In the middle of the bottom surface of the driven gear 8, a stabilizing seat 13 is rotatably connected, and the stabilizing seat 13 is fixedly connected to the inner bottom surface of the gearbox 1. Through the cooperation of the sealing cover 5 and the stabilizing seat 13, it is convenient to stabilize the working environment of the transmission component.

[0024] Working principle: When the present invention is in use, first select a gearbox 1, a servo motor 3, and a telescopic box 4 with appropriate transmission ratios according to requirements. Then place the top plate of the gearbox 1 facing upwards, align the servo motor 3 with the connecting shaft of the driving gear 6 passing through the top plate, and then install the servo motor 3 with screws. Then align the bearing block 2 with the connecting shaft of the driven gear 8 passing through the top plate, and then install the bearing block 2 with screws. At this time, the rotating shaft of the servo motor 3 is coaxially connected to the driving gear 6, and the rotating shaft in the bearing block 2 is coaxially connected to the driven gear 8. Then install and fix the telescopic box 4 on the bearing block 2. At this time, the threaded rod 9 is coaxially connected to the rotating shaft in the bearing block 2. Finally, sleeved the sealing cover 5 on the outer side of the telescopic tube 11 and install it on the top surface of the telescopic box 4 to complete the installation of the device; When the servo motor 3 is powered on, it will drive the driving gear 6 to rotate, thereby driving the transmission gear 7 to rotate, and finally driving the driven gear 6 to rotate. The power is transmitted to the threaded rod 9 through the bearing block 2, thereby driving the threaded sleeve 10 to slide up and down in the telescopic box 4, and finally driving the connecting block at the top of the telescopic tube 11 to move up and down outside the device, realizing the movement of the mechanical joint.

[0025] A control system for an electric cylinder used in a robotic joint arm. The control system includes a sensing and acquisition module, a controller, and a driver; The sensing and acquisition module is used to collect the actual working state data of the electric cylinder in real time and transmit it to the controller; The controller includes an instruction parsing unit, a state analysis unit, a fault diagnosis unit, a communication management unit, and a parameter storage unit; The instruction parsing unit is used to receive the task instruction from the upper computer, and parse out the control parameters xi of the electric cylinder from the task instruction, including the target displacement x1, the target speed x2, and the target thrust x3; where i represents the index of the parameter in the control parameters, and i = 1, 2, or 3; The state analysis unit is used to receive the actual working state data of the electric cylinder, perform state analysis on the actual working state data of the electric cylinder, analyze the difference between the actual working state data and the control parameters of the electric cylinder in the task instruction to obtain the state evaluation value corresponding to the parameter, and compare the state evaluation value with its threshold value to obtain the adjustment signal corresponding to the parameter, and calculate the control signal of the servo motor 3; The fault diagnosis unit is used to receive the state evaluation value corresponding to the parameter, set the fault diagnosis threshold corresponding to the parameter in the control parameters. If the state evaluation value is greater than its fault diagnosis threshold, generate a state fault signal corresponding to the state evaluation value; Mark the state fault signal and the corresponding parameter, generation time, state evaluation value, number of the electric cylinder, and position as fault information; The parameter storage unit is used to store various parameters of the system. The various parameters include the mechanical parameters, control parameters of the electric cylinder, and the state evaluation values and fault diagnosis thresholds of the parameters; The communication management unit is used to coordinate the communication between the controller, the driver and each module; The driver is used to convert the control signal calculated by the controller into a three-phase AC voltage using space vector pulse width modulation technology and apply it to the servo motor 3 when receiving the parameter adjustment signaling, so as to drive the output shaft of the servo motor 3 to rotate, drive the transmission assembly of the gearbox 1 to operate, and then drive the telescopic assembly to achieve telescopic movement.

[0026] In this application, the specific operation mechanism of the state analysis unit is as follows: Obtain the actual working state data yi of the electric cylinder sent by the sensing and acquisition module, including the actual displacement y1, the actual speed y2 and the actual torque y3; calculate the difference between the parameters in the actual working state data of the electric cylinder and the corresponding parameters of the control parameters in its task instruction to obtain the corresponding target deviation value of the parameter , the formulas are respectively expressed as: displacement deviation value: , speed deviation value: , thrust deviation value: , k is the conversion coefficient corresponding to the preset conversion relationship between torque and thrust; Use the PID control algorithm to calculate the control signal of the servo motor 3 , the formula is expressed as: ; where, represents the target deviation value corresponding to parameter i, Kpi, Kji, Kdi respectively represent the proportional coefficient, integral coefficient, and differential coefficient corresponding to parameter i, represents the integral of the target deviation value of v changing with time from the initial moment to the current moment, represents the change rate of the target deviation value with respect to parameter i; Perform weighted processing on all the control signals in the control parameters of the servo motor 3 to obtain the relevant adjustment factor t corresponding to the parameter, the formula is expressed as: ; where, ia represents the weight corresponding to parameter i; use the relevant adjustment factor t corresponding to the parameter to adjust and update the control signal of the servo motor 3; Mark the time region between the starting moment and the current moment of the electric cylinder as the dynamic monitoring time zone; Obtain the target deviation value of the parameter in the control parameter at any acquisition moment within the dynamic monitoring time zone, calculate the statistical indicators of the target deviation value of the parameter within the dynamic monitoring time zone, including the maximum value, minimum value, average value, and standard deviation; perform weighted calculation on the target deviation value at the current moment and all the indicators in its statistical indicators to obtain the state evaluation value of the parameter; set the evaluation threshold of any parameter in the control parameter, if the state evaluation value is greater than its evaluation threshold, it means that the parameter corresponding to the state evaluation value has a deviation, and generate the adjustment signaling corresponding to the parameter.

[0027] In this application, the specific operation mechanism of the communication management unit is as follows: it is used to regularly send data requests to sensors using industrial communication protocols and receive data responses sent by the sensors. The data responses from all sensors constitute the actual working state data of the electric cylinder. It is also used to receive task instructions from the host computer through the Ethernet protocol and upload the actual working state data and fault information of the electric cylinder to the host computer. It is further used to send the control signal calculated by the controller to the driver using the space vector pulse width modulation protocol.

[0028] In this application, the sensing and acquisition module includes a displacement sensor, a torque sensor, and a speed sensor; The displacement sensor is installed at the telescopic part of the electric cylinder using a linear variable differential transformer and is used to measure the telescopic displacement of the electric cylinder, marked as the actual displacement. The torque sensor is installed on the power transmission path of the electric cylinder and is used to measure the output torque of the electric cylinder, marked as the actual torque. The speed sensor is used to detect the magnetic field change frequency of the rotating component and calculate the linear velocity according to the formula of the product of the radius and angular velocity of the rotating component, and then calculate the moving speed of the electric cylinder, marked as the actual speed. The actual displacement, actual speed, and actual torque of the electric cylinder are marked as the actual working state data of the electric cylinder.

[0029] Those skilled in the art will readily conceive of other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present invention, which follow the general principles of the present invention and include known common knowledge or conventional technical means in the technical field not disclosed in this disclosure. The specification and examples are only considered exemplary, and the true scope and spirit of the present invention are pointed out by the following claims.

[0030] It should be understood that the present invention is not limited to the precise structures already described and shown in the drawings, and various modifications and changes can be made without departing from its scope. The scope of the present invention is only limited by the appended claims.

Claims

1. An electric cylinder used for a robotic articulated arm, characterized in that, It includes a gearbox (1), on one side of the top surface of which a bearing block (2) is fixedly installed by screws. On one side of the bearing block (2), there is a servo motor (3), which is fixedly installed on the top surface of the gearbox (1) by screws. On the top surface of the bearing block (2), a telescopic box (4) is fixedly installed, and on the top surface of the telescopic box (4), a sealing cover (5) is fixedly installed. A transmission component is arranged inside the gearbox (1), and a telescopic component is arranged inside the telescopic box (4).

2. The electric cylinder used for the robotic articulated arm according to claim 1, wherein The transmission component includes the gearbox (1), which is composed of a box body and a top plate. On one side of the bottom surface of the top plate, a driving gear (6) is rotatably connected. On one side of the driving gear (6), there is a speed-changing gear (7), which is rotatably connected to the middle of the bottom surface of the top plate. The speed-changing gear (7) has two upper and lower layers. The upper layer of the speed-changing gear (7) is in mating contact with the driving gear (6), and on one side of the lower layer of the speed-changing gear (7), there is a driven gear (8) in mating contact, which is rotatably connected to the bottom surface of the top plate.

3. The electric cylinder used for the robotic articulated arm according to claim 2, characterized in that, The top surfaces of the driving gear (6) and the driven gear (8) both penetrate through the top plate and are respectively connected to the servo motor (3) and the bearing block (2). Inside the center of the bearing block (2), there is a bearing (12). Inside the bearing (12), there is a rotating shaft. The lower end of the rotating shaft is fixedly connected to the driven gear (8), and the upper end of the rotating shaft is fixedly connected to a threaded rod (9).

4. The electric cylinder used for the robotic articulated arm according to claim 1, characterized in that, The telescopic component includes the threaded rod (9), on the outer side surface of which there is an external thread. On the external thread surface of the threaded rod (9), a threaded sleeve (10) is arranged in a mating manner. On the left and right sides of the outer side surface of the threaded sleeve (10), splines are fixedly connected. On the inner side surface of the telescopic box (4), spline grooves are arranged in a mating manner with the splines. On the top surface of the threaded sleeve (10), a telescopic tube (11) is fixedly connected.

5. An electric cylinder for use in a robotic articulated arm according to claim 4, characterized in that, The top end of the telescopic tube (11) penetrates through the sealing cover (5) and is fixedly connected to a connecting block. At the abutting position of the sealing cover (5) and the telescopic tube (11), there is a sealing ring.

6. The electric cylinder used for a robotic articulated arm according to claim 3, characterized in that, In the middle of the bottom surface of the driven gear (8), a stabilizing seat (13) is rotatably connected, and the stabilizing seat (13) is fixedly connected to the inner bottom surface of the gearbox (1).

7. A control system for an electric cylinder used in a robotic articulated arm, which uses the electric cylinder for a robotic articulated arm according to any one of claims 1-6, characterized in that, The control system includes a sensing and acquisition module, a controller, and a driver; The sensing and acquisition module is used to collect the actual working state data of the electric cylinder in real time and transmit it to the controller; The controller includes an instruction parsing unit, a state analysis unit, a fault diagnosis unit, a communication management unit, and a parameter storage unit; The instruction parsing unit is used to receive the task instruction from the upper computer and parse out the control parameters xi of the electric cylinder from the task instruction, including the target displacement x1, the target speed x2, and the target thrust x3; where i represents the index of the parameters in the control parameters, and i = 1, 2, or 3; The state analysis unit is used to receive the actual working state data of the electric cylinder, perform state analysis on the actual working state data of the electric cylinder, analyze the difference between the actual working state data and the control parameters of the electric cylinder in the task instruction to obtain the state evaluation value corresponding to the parameter, compare the state evaluation value with its threshold value to obtain the adjustment signaling corresponding to the parameter, and calculate the control signal of the servo motor (3); The fault diagnosis unit is used to receive the state evaluation value corresponding to the parameter, set the fault diagnosis threshold corresponding to the parameter in the control parameter. If the state evaluation value is greater than its fault diagnosis threshold, a state fault signal corresponding to the state evaluation value is generated; the state fault signal, the corresponding parameter, the generation time, the state evaluation value, the number of the electric cylinder, and the position are marked as fault information. The parameter storage unit is used to store various parameters of the system, and the various parameters include the mechanical parameters of the electric cylinder, the control parameters, the state evaluation value of the parameter, and the fault diagnosis threshold. The communication management unit is used to coordinate the communication between the controller, the driver and each module. The driver is used to, when receiving the adjustment signal of the parameter, convert the control signal calculated by the controller into a three-phase AC voltage using the space vector pulse width modulation technology and apply it to the servo motor (3), so as to drive the output shaft of the servo motor (3) to rotate, drive the transmission assembly of the gearbox (1) to operate, and then drive the telescopic assembly to realize the telescopic movement.

8. The control system of an electric cylinder used for a robotic articulated arm according to claim 7, characterized in that, The specific operation mechanism of the state analysis unit is as follows: Obtain the actual working state data yi of the electric cylinder sent by the sensing and acquisition module, including the actual displacement y1, the actual speed y2, and the actual torque y3; calculate the difference between the parameters in the actual working state data of the electric cylinder and the corresponding parameters of the control parameters in its task instruction to obtain the target deviation value corresponding to the parameter , the formulas are respectively expressed as: displacement deviation value: , speed deviation value: , thrust deviation value: , where k is the conversion coefficient corresponding to the preset conversion relationship between torque and thrust; Calculate the control signal of the servo motor 3 using the PID control algorithm , which is expressed by the formula: ; where represents the target deviation value corresponding to parameter i, and Kpi, Kji, and Kdi respectively represent the proportional coefficient, integral coefficient, and differential coefficient corresponding to parameter i, represents the integral of the target deviation value of v changing with time from the initial moment to the current moment, represents the change rate of the target deviation value with respect to parameter i; All control signals in the control parameters of the servo motor (3) are weighted to obtain the relevant adjustment factor t corresponding to the parameter, which is expressed by the formula: ; where ia represents the weight corresponding to parameter i; the control signal of the servo motor (3) is adjusted and updated using the relevant adjustment factor t corresponding to the parameter. The time region between the start time of the electric cylinder and the current time is marked as the dynamic monitoring time zone. Obtain the target deviation value of the parameter in the control parameter at any acquisition time in the dynamic monitoring time zone, calculate the statistical indexes of the target deviation value of the parameter in the dynamic monitoring time zone, including the maximum value, the minimum value, the average value, and the standard deviation; perform a weighted calculation on the target deviation value at the current time and all the indexes in its statistical indexes to obtain the state evaluation value of the parameter; set the evaluation threshold of any parameter in the control parameter. If the state evaluation value is greater than its evaluation threshold, it indicates that the parameter corresponding to the state evaluation value has a deviation, and an adjustment signal corresponding to the parameter is generated.

9. The control system of an electric cylinder used for a robotic joint arm according to claim 7, characterized in that, The specific operation mechanism of the communication management unit is: used to regularly send data requests to the sensors using the industrial communication protocol and receive the data responses sent by the sensors. The data responses of all sensors constitute the actual working state data of the electric cylinder; also used to receive the task instructions from the upper computer through the Ethernet protocol and upload the actual working state data and fault information of the electric cylinder to the upper computer; also used to adopt the space vector pulse width modulation protocol to send the control signal calculated by the controller to the driver.

10. The control system of an electric cylinder used for a robotic articulated arm according to claim 7, characterized in that, The sensing and acquisition module includes a displacement sensor, a torque sensor and a speed sensor. The displacement sensor is installed at the telescopic part of the electric cylinder using a linear variable differential transformer and is used to measure the telescopic displacement of the electric cylinder, marked as the actual displacement; the torque sensor is installed on the power transmission path of the electric cylinder and is used to measure the output torque of the electric cylinder, marked as the actual torque; the speed sensor is used to detect the magnetic field change frequency of the rotating part, and according to the calculation formula, the product of the radius of the rotating part and the angular velocity is used to obtain the linear velocity, and the movement speed of the electric cylinder is calculated and marked as the actual speed; the actual displacement, actual speed, and actual torque of the electric cylinder are marked as the actual working state data of the electric cylinder.

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