CN114248269A - TherCAT-based electric six-axis robot control system and control method - Google Patents

TherCAT-based electric six-axis robot control system and control method Download PDF

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Publication number
CN114248269A
CN114248269A CN202111499944.4A CN202111499944A CN114248269A CN 114248269 A CN114248269 A CN 114248269A CN 202111499944 A CN202111499944 A CN 202111499944A CN 114248269 A CN114248269 A CN 114248269A
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China
Prior art keywords
plc
axis robot
control system
module
joint
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CN202111499944.4A
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Chinese (zh)
Inventor
黄旻
江杰迪
杨帆
陈磊
蔡启
孙圆正
孙明广
高攀
施海峰
袁国珍
高忠旭
王晓明
樊卡
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State Grid Zhejiang Electric Power Co Ltd Haining Power Supply Co
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State Grid Zhejiang Electric Power Co Ltd Haining Power Supply Co
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Priority to CN202111499944.4A priority Critical patent/CN114248269A/en
Publication of CN114248269A publication Critical patent/CN114248269A/en
Pending legal-status Critical Current

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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B25HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25JMANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES
    • B25J9/00Programme-controlled manipulators
    • B25J9/16Programme controls
    • B25J9/1602Programme controls characterised by the control system, structure, architecture
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B25HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25JMANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES
    • B25J9/00Programme-controlled manipulators
    • B25J9/16Programme controls
    • B25J9/1602Programme controls characterised by the control system, structure, architecture
    • B25J9/1605Simulation of manipulator lay-out, design, modelling of manipulator
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B25HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25JMANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES
    • B25J9/00Programme-controlled manipulators
    • B25J9/16Programme controls
    • B25J9/1656Programme controls characterised by programming, planning systems for manipulators
    • B25J9/1664Programme controls characterised by programming, planning systems for manipulators characterised by motion, path, trajectory planning

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  • Engineering & Computer Science (AREA)
  • Robotics (AREA)
  • Mechanical Engineering (AREA)
  • Automation & Control Theory (AREA)
  • Manipulator (AREA)
  • Numerical Control (AREA)

Abstract

The invention discloses an electric six-axis robot control system based on TherCAT, which is characterized by comprising a Personal Computer (PC), a Programmable Logic Controller (PLC) master control system, wherein the PC performs data interaction with a PLC system through an automatic dependent surveillance system (ADS) protocol, the PLC master control system comprises a PLC master station and a plurality of PLC slave stations, the PLC master station and the PLC slave stations respectively perform data interaction by adopting EtherCAT, and the PLC master station and the PLC slave stations perform data interaction with the PC based on the ADS protocol; the PLC slave station comprises a motion controller and a logic controller which respectively correspond to the six-axis robot joints. And the data transmission between the PLC master station and the PLC slave station is realized by adopting an EtherCAT communication mode, and the data compatibility is good. A variable error analysis algorithm is injected into the six-axis robot joint, and data reference is provided for installation and debugging of the robot joint and an opening method of a control algorithm. TwinCAT is used as a master control core, and a distributed clock technology is adopted to ensure clock synchronization among EtherCAT slave station modules.

Description

TherCAT-based electric six-axis robot control system and control method
Technical Field
The invention relates to the field of industrial automation control, in particular to a control system and a control method of a six-axis electric robot based on TherCAT.
Background
With the increasing expansion of national power grid scale, the safety concept becomes a most core part of power grid enterprise culture, and personal, power grid and equipment safety is a premise and foundation of all work. However, at present, there are still the operator maloperation, the operation danger coefficient of ascending a height is high, transmission line has the foreign matter to hang reality problems such as not good clearance, along with the improvement of industrial automation level, industrial robot replaces manual work in more fields, but the control of robot puts forward higher and higher requirements to speed and precision, for guaranteeing that industrial robot accurately accomplishes action and operation, its corresponding control system seems important especially, traditional arm control system communication mode bottom line response time overlength needs multiple protocol conversion, can't satisfy diversified communication demand, thereby influence the response speed and the action precision of arm.
Disclosure of Invention
The invention provides a high-precision and quick-response electric six-axis robot control system and method based on TherCAT, aiming at overcoming the problem that the motion precision and corresponding speed of an industrial robot in the prior art are influenced by a traditional communication mode and a control method.
In order to achieve the purpose, the invention adopts the following technical scheme:
a six axis robot control system of electric power based on TherCAT, characterized by, including people's PC, PLC master control system, the said PC carries on the data interaction through ADS agreement with PLC system, the said PLC master control system includes PLC master station and several PLC slave stations, adopt EtherCAT to carry on the data interaction between said PLC master station and several PLC slave stations separately, said PLC master station and PLC slave station carry on the data interaction with PC based on ADS agreement; the PLC slave station comprises a motion controller and a logic controller which respectively correspond to the six-axis robot joints. The PLC master station adopts a Beifu CX9020 series controller, the kernel of the controller is a WinCe operating system, the PLC slave station adopts a Beifu EL7201-0010 compact servo terminal module, the six-axis robot mechanical arm has high control precision and high safety and reliability, can replace operators to carry out operation with high risk coefficient, the robot end effector can be connected with different execution devices to realize different functions,
preferably, the six-axis robot comprises an indicating module and a sensing module, wherein the indicating module is connected with the logic controller through an output module, and the sensing module is connected with the logic controller through an input module. The indicating module is an indicating lamp, the sensing module is a plurality of sensors, the logic controller directly reads and writes Input and Output variables of the Output module connected with the indicating lamp through a preset PLC program, and the logic controller directly reads and writes Input and Output variables of the Input module connected with the sensors through the preset PLC program, so that IO equipment is controlled.
Preferably, the six-axis robot comprises a servo module and a position feedback module, and the servo module and the position feedback module are connected with the motion controller through a servo driving module. The servo module selects a BECKHOFF servo motor with the model number of AM8111-1F 21-0000.
Preferably, the PLC master station includes an EtherCAT master station, a register, an ethernet network interface, and a network interface card, and the EtherCAT master station includes an ethernet controller and a data transceiver integrated inside the network interface card. The register is used for storing PLC programs transmitted by the PC, the Ethernet network interface and the Ethernet controller are both in standard configuration, and the network interface card adopts NIC, so that the applicability is good.
Preferably, the PLC slave station includes an EtherCAT slave station, a register, and an ethernet network interface, and the EtherCAT slave station includes an ESC chip. And the ESC chip calls input data corresponding to the data frame in the external register, inserts the input data into the corresponding position of the data message, and then transmits the data frame information to the next adjacent slave station module through the EtherCAT network until the data reaches the last slave station module and then transmits the data back to the PLC master station.
Preferably, the PLC master station and the PLC slave station are realized by a TwinCAT soft PLC system. The TwinCAT is used as a master control core for realizing communication connection and configuration of system hardware resources and realizing real-time control of the hardware resources, and has flexible and reconfigurable flow control capability, the TwinCAT adopted by the PLC master control system is an automatic control software platform based on a Windows operating system, system configuration and PLC programming and debugging functions can be realized, and a distributed clock technology is adopted to ensure clock synchronization among EtherCAT slave station modules.
Preferably, all six joints of the six-axis robot are rotary joints, the two joints are connected through connecting rods, and the servo module comprises a plurality of AM8111 servo motors. And realizing the cooperative control of six shafts.
A control method of an electric six-axis robot based on TherCAT comprises the following steps:
s1: building each joint of the six-axis robot, and then combining the joints to build a six-axis robot model;
s2: data transmission between the PLC master station and the PLC slave station is realized by using EtherCAT;
s3: planning a motion path of the robot by using kinematics simulation;
s4: injecting errors into all joints of the mechanical arm, analyzing the sensitivity degree of each joint to the injected errors, and outputting joint error sensitivity sequencing;
s5: according to the output joint error sensitivity, the joint precision with high error sensitivity is improved. In the process of manufacturing and assembling the robot, the installation accuracy of the posture and the position of the joint is improved, so that the error of the joint is reduced.
Preferably, the step S2 includes that the ESC calls input data corresponding to the data frame in the external register, and inserts the input data into a corresponding position of the data packet, and then transmits the data frame information to the next adjacent slave module through the EtherCAT network until the data reaches the last slave module, and then transmits the data back to the PLC master station.
Preferably, step S4 includes injecting errors in the preset proportion of the current joint motion range into each joint in sequence, and measuring a difference between the actual moving position and the preset moving position of each joint, where a larger difference indicates a higher sensitivity of the joint to the errors, and a smaller difference indicates a lower sensitivity of the joint to the errors.
Therefore, the invention has the following beneficial effects: (1) and the data transmission between the PLC master station and the PLC slave station is realized by adopting an EtherCAT communication mode, and the data compatibility is good. (2) A variable error analysis algorithm is injected into the six-axis robot joint, and data reference is provided for installation and debugging of the robot joint and an opening method of a control algorithm. (3) TwinCAT is used as a master control core, and a distributed clock technology is adopted to ensure clock synchronization among EtherCAT slave station modules.
Drawings
Fig. 1 is a block diagram of a robot control system according to an embodiment of the present invention.
Fig. 2 is a schematic diagram of EtherCAT operation according to an embodiment of the present invention.
Detailed Description
The invention is further described with reference to the following detailed description and accompanying drawings.
Example (b):
the TherCAT-based electric six-axis robot control system comprises a PC (personal computer), a PLC (programmable logic controller) main control system, a plurality of indicating lamps, a plurality of sensors, a plurality of servo motors and a position feedback module corresponding to the servo motors, wherein all six joints of the six-axis robot are rotary joints, and the two joints are connected through a connecting rod. The six-axis robot mechanical arm is high in control precision and safety and reliability, can replace operators to perform operation with high risk factor, and the robot end effector can be connected with different execution devices to realize different functions of electric power work.
The PC machine performs data interaction with the PLC system through an ADS protocol, the PLC master control system comprises a PLC master station and a plurality of PLC slave stations, EtherCAT is respectively adopted between the PLC master station and the PLC slave stations for data interaction, and the PLC master station and the PLC slave stations perform data interaction with the PC machine based on the ADS protocol; and the PLC master station and the PLC slave station are realized by a TwinCAT soft PLC system. The TwinCAT is used as a master control core for realizing communication connection and configuration of system hardware resources and realizing real-time control of the hardware resources, and has flexible and reconfigurable flow control capability, the TwinCAT adopted by the PLC master control system is an automatic control software platform based on a Windows operating system, system configuration and PLC programming and debugging functions can be realized, and a distributed clock technology is adopted to ensure clock synchronization among EtherCAT slave station modules.
The PLC slave station comprises a motion controller and a logic controller which respectively correspond to the six-axis robot joints. The PLC main station adopts a Beifu CX9020 series controller, the inner core of the controller is a WinCe operating system, the PLC main station further comprises an EtherCAT main station, a register, an Ethernet network interface and a network interface card, and the EtherCAT main station comprises an Ethernet controller and a data transceiver which are integrated in the network interface card. The register is used for storing PLC programs transmitted by the PC, the Ethernet network interface and the Ethernet controller are both in standard configuration, and the network interface card adopts NIC, so that the applicability is good.
The PLC slave station adopts a Beifu EL7201-0010 compact servo terminal module, and further comprises an EtherCAT slave station, a register and an Ethernet network interface, wherein the EtherCAT slave station comprises an ESC chip. And the ESC chip calls input data corresponding to the data frame in the external register, inserts the input data into the corresponding position of the data message, and then transmits the data frame information to the next adjacent slave station module through the EtherCAT network until the data reaches the last slave station module and then transmits the data back to the PLC master station.
The logic controller directly reads and writes Input and Output variables of an Output module connected with the indicator lamp through a preset PLC program, and the logic controller directly reads and writes Input and Output variables of an Input module connected with the sensor through a preset PLC program, so that simple IO equipment is controlled. The servo motor and the position feedback module are connected with the motion controller through the servo driving module. The servo motor is BECKHOFF servo motor with the model number of AM8111-1F 21-0000.
The invention also discloses a control method of the electric six-axis robot based on TherCAT, which comprises the following steps: the method comprises the following steps: s1: building each joint of the six-axis robot, and then combining the joints to build a six-axis robot model;
s2: data transmission between the PLC master station and the PLC slave station is realized by using EtherCAT; and the ESC chip calls input data corresponding to the data frame in the external register, inserts the input data into the corresponding position of the data message, and then transmits the data frame information to the next adjacent slave station module through the EtherCAT network until the data reaches the last slave station module and then transmits the data back to the PLC master station.
S3: planning a motion path of the robot by using kinematics simulation;
s4: injecting errors into all joints of the mechanical arm, analyzing the sensitivity degree of each joint to the injected errors, and outputting joint error sensitivity sequencing; and injecting errors in the preset proportion of the current joint motion range into each joint in sequence, and measuring the difference between the actual moving position and the preset moving position of each joint, wherein the larger the difference is, the higher the sensitivity of the joint to the errors is, and the smaller the difference is, the lower the sensitivity of the joint to the errors is.
S5: according to the output joint error sensitivity, the joint precision with high error sensitivity is improved. In the process of manufacturing and assembling the robot, the installation accuracy of the posture and the position of the joint is improved, so that the error of the joint is reduced.
The specific embodiments described herein are merely illustrative of the spirit of the invention. Various modifications or additions may be made to the described embodiments or alternatives may be employed by those skilled in the art without departing from the spirit or ambit of the invention as defined in the appended claims.
Although terms such as TherCAT, ADS protocol, PLC, registers, error analysis algorithm, etc. are used more often herein, the possibility of using other terms is not excluded. These terms are used merely to more conveniently describe and explain the nature of the present invention; they are to be construed as being without limitation to any additional limitations that may be imposed by the spirit of the present invention.

Claims (10)

1. A six axis robot control system of electric power based on TherCAT, characterized by, including PC, PLC master control system, the said PC carries on the data interaction through ADS agreement with PLC system, the said PLC master control system includes PLC master station and several PLC slave stations, adopt EtherCAT to carry on the data interaction between said PLC master station and several PLC slave stations separately, said PLC master station and PLC slave station carry on the data interaction with PC based on ADS agreement; the PLC slave station comprises a motion controller and a logic controller which respectively correspond to the six-axis robot joints.
2. The TherCAT-based power six-axis robot control system as claimed in claim 1, wherein the six-axis robot comprises an indication module and a sensing module, the indication module is connected with the logic controller through an output module, and the sensing module is connected with the logic controller through an input module.
3. The TherCAT-based electric power six-axis robot control system as claimed in claim 2, wherein the six-axis robot comprises a servo module and a position feedback module, and the servo module and the position feedback module are connected with the motion controller through a servo driving module.
4. The TherCAT-based power six-axis robot control system as claimed in claim 3, wherein the PLC master station comprises an EtherCAT master station, a register, an Ethernet network interface and a network interface card, and the EtherCAT master station comprises an Ethernet controller and a data transceiver integrated in the network interface card.
5. The TherCAT-based electric power six-axis robot control system as claimed in claim 4, wherein the PLC slave station comprises an EtherCAT slave station, a register and an Ethernet network interface, and the EtherCAT slave station comprises an ESC chip.
6. The six-axis robot control system of electric power based on TherCAT of claim 5, wherein the PLC master station and the PLC slave station are realized by a double-happiness soft PLC system TwinCAT.
7. The TherCAT-based electric power six-axis robot control system as claimed in claim 6, wherein all six joints of the six-axis robot are rotary joints, the two joints are connected through a connecting rod, and the servo module comprises a plurality of AM8111 servo motors.
8. A control method of an electric six-axis robot based on TherCAT is based on the control system of any one of claims 1 to 7, and is characterized by comprising the following steps:
s1: building each joint of the six-axis robot, and then combining the joints to build a six-axis robot model;
s2: data transmission between the PLC master station and the PLC slave station is realized by using EtherCAT;
s3: planning a motion path of the robot by using kinematics simulation;
s4: injecting errors into all joints of the mechanical arm, analyzing the sensitivity degree of each joint to the injected errors, and outputting joint error sensitivity sequencing;
s5: according to the output joint error sensitivity, the joint precision with high error sensitivity is improved.
9. The method as claimed in claim 8, wherein the step S2 includes the ESC calling input data corresponding to the data frame in the external register, inserting the input data into a corresponding position of the data packet, and then transmitting data frame information to the next adjacent slave module through the EtherCAT network until the data reaches the last slave module and then transmitting the data back to the PLC master station.
10. The method as claimed in claim 9, wherein the step S4 includes injecting errors in a preset ratio of a current joint motion range into each joint in sequence, and measuring a difference between an actual moving position and a preset moving position of each joint, wherein a larger difference indicates a higher sensitivity of the joint to the errors, and a smaller difference indicates a lower sensitivity of the joint to the errors.
CN202111499944.4A 2021-12-09 2021-12-09 TherCAT-based electric six-axis robot control system and control method Pending CN114248269A (en)

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CN115378761A (en) * 2022-09-27 2022-11-22 傲拓科技股份有限公司 EtherCAT master station system rapid implementation method based on PLC

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