CN113386134A - Coordinate type welding robot control system and method and robot - Google Patents

Abstract

The invention provides a coordinate type welding robot control system, a coordinate type welding robot control method and a robot, wherein the coordinate type welding robot control system comprises an upper computer, a lower computer, a hardware module and robot peripheral equipment, wherein the upper computer is connected with the lower computer, and the upper computer is used for inputting and/or outputting a motion control instruction; the lower computer is used for operating a control algorithm and generating control logic for controlling the welding machine; the hardware module is used for receiving the control logic through the expansion board interface and transmitting the control logic to the robot peripheral equipment. The communication protocol of the system is a TCP protocol, so that the possibility of packet loss can be avoided from the bottom layer to a certain extent; the gun cleaning station is supported, so that sticking blockage generated in the working process of the welding robot and shallow objects in a gas protection sleeve of the welding gun can be cleaned, the gas is ensured to be smooth for a long time, and the quality of a welding seam is improved; the wire feeder is supported, the wire feeding precision is ensured, and the utilization rate of welding wires is improved; supporting the external shaft linkage coupling processing, sometimes need to cooperate with two axis displacement body, so design 8 axle drives.

Description

Coordinate type welding robot control system and method and robot

Technical Field

The invention relates to the technical field of industrial robot control, in particular to a coordinate type welding robot control system and method and a robot.

Background

According to the development report of the Chinese robot industry, the market of the Chinese robot is about 1/3 worldwide, the market is expected to increase from 57.3 hundred million dollars to 70 hundred million dollars in 2019 in 2021, the welding robot accounts for more than 40% of the global industrial robot at present, the welding robot can work in high-risk environments such as high temperature, oxygen deficiency, toxicity and the like, the repetitive work can be well completed, and the production efficiency of the factory is improved. The repeatability precision and stability of the welding robot are closely related to the stability and reliability of software and hardware of a control system.

The software and hardware that controls the welding robot trajectory planning is referred to as the welding robot control system. Most of traditional demonstrator in the welding robot system is developed based on Linux and WinCE, WinCE has rich GUI library and can shorten the development period, but the traditional demonstrator does not support cross-platform. The Linux kernel is small, the resource occupancy rate is low, and the graphical interface support effect is poor.

Welding systems are various in variety, and can be divided into control systems with a single chip microcomputer, a PLC, a special microprocessor, a PC + motion control card and embedded chips such as ARM, DSP and FPGA as cores on the structure of a single processor. Early robotic controllers often employed MCU-based controllers. However, with the development of the technology, the calculation speed of the controller is greatly increased, and the requirement of performing high-speed calculation on a complex algorithm cannot be met only by a single chip microcomputer. Later, a plurality of manufacturers provide a whole set of solutions with the PLC as a core controller, and the robot system with the PLC as the core has the advantages of mature and reliable technology, good expansibility, interchangeability and the like, and greatly shortens the development period, but the PLC does not support complex algorithms, has simpler processed data, and cannot meet complex motion tracks of multi-axis linkage. And then a PC + motion control card is taken as the core of the robot control system. The motion control card can be used in various motion occasions, mostly used for controlling a stepping motor and a servo motor, can fully utilize the resources of a PC (personal computer), controls the motion of a robot in real time and detects the state of the robot, ensures the position and speed control precision of a system, can reduce the development time, but has high cost and is not beneficial to secondary development.

Disclosure of Invention

The invention solves the main problems of poor stability and reliability of the traditional welding robot control system and high development cost of the controller.

The invention provides a coordinate type welding robot control system which comprises an upper computer, a lower computer, a hardware module and robot peripheral equipment, wherein the upper computer is connected with the lower computer and used for inputting and/or outputting a motion control command;

the lower computer is used for operating a control algorithm and generating control logic for controlling the welding machine;

and the hardware module is used for receiving the control logic through an expansion board interface and transmitting the control logic to the robot peripheral equipment.

Further, the system architecture of the lower computer is as follows:

an SOC FPGA architecture or an ARM + FPGA architecture, the SOC FPGA architecture being an SOC chip integrating an ARM processor and an FPGA on a single chip.

Further, the host computer includes:

the demonstrator is developed by using an Android system and is used for realizing man-machine interaction, teaching, editing application programs, setting control equipment parameters and displaying the state of the current controlled object.

Further, the host computer still includes:

and the remote rod control is used for sending a control instruction to the demonstrator through a serial port on the remote rod sampling plate.

Further, the demonstrator is also used for converting the control command and sending the converted control command to the lower computer.

Further, the robot peripheral device includes:

the welding machine comprises a digital welding machine, a shaft motor driver, a position sensor, a welding seam tracking device, a wire feeder and a gun cleaning station;

the digital welding machine is connected with the hardware module through a first IO expansion interface;

the shaft motor drive receives the pulse differential signal sent by the hardware module and drives the shaft motor to operate;

the position sensor is connected with the hardware module through a second IO expansion interface;

the welding seam tracking device is in communication connection with the hardware module through an expansion serial port on the expansion board;

the wire feeder is connected with the hardware module through a third IO expansion interface or is in communication connection with the hardware module through the expansion serial port;

and the gun cleaning station is connected with the hardware module through a fourth IO expansion interface, or is in communication connection with the hardware module through the expansion serial port.

Further, the shaft motor drive is an 8-shaft drive.

Further, the host computer still includes:

the software control layer is used for monitoring a user button event and a rocker serial port event so as to obtain monitoring information;

and the software view layer is used for updating the view after receiving the monitoring information and inputting a control instruction.

According to another aspect of the present invention, there is also disclosed a coordinate type welding robot motion control method, characterized in that the coordinate type welding robot control method is implemented when the coordinate type welding robot control system as described in any one of the preceding paragraphs is operated, and the coordinate type welding robot control method includes:

analyzing the thread data to obtain an original joint angle of the demonstrator;

planning a motion track and a motion speed to obtain an interpolated target joint angle sequence;

converting the target joint angle sequence into the pulse number sent by the shaft of the shaft motor at each moment;

sending the pulse number to an FPGA to drive a motor to rotate;

monitoring the thread while the motor rotates to obtain the amount of motion of the shaft motor;

and transmitting the motion amount back to an upper computer for data storage and display.

According to yet another aspect of the present invention, there is also disclosed a coordinate type welding robot characterized in that the coordinate type welding robot comprises a robot body and a coordinate type welding robot control system as described in any one of the foregoing, the coordinate type welding robot control system being configured to control the robot body to perform welding.

The embedded processor is adopted as a system core controller on the main controller, and the SoC FPGA framework of the core controller has the advantages of high-speed parallel processing and flexible customization of the FPGA and the advantages of the ARM processor in the aspects of flexible control, graphical interface display and network transmission. Compared with a processor and FPGA structure, the communication bandwidth and the communication efficiency between the processor and the FPGA are greatly improved. The SoC FPGA adopts an on-chip integration mode, the FPGA and the HPS system are integrated on the same chip, a data bit width of up to 128 bits is designed between the FPGA and the HPS system, the operating frequency reaches 200MHz, and the communication bandwidth and the communication efficiency between the FPGA and the HPS system are greatly improved. The SoC system can be customized according to engineering requirements, peripherals, a memory and interfaces can be selected, and own specific functions can be embedded, because the welding robot control system needs to work in a stable and reliable heat dissipation environment, the embedded IC has low power consumption and small volume, and the stability and reliability of the system can be effectively ensured due to the fan-free design; in addition, the method has the characteristics of low cost, high reliability, good expansibility, open technical data, low development difficulty and multiple tasks, and can effectively improve the data processing speed.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description, serve to explain the principles of the invention.

Fig. 1 is a schematic diagram of the general architecture of a welding robot control system according to an embodiment of the present invention.

Fig. 2 is a schematic diagram of a hardware design structure of the SoC simplified system in the embodiment of the present invention.

FIG. 3 is a schematic diagram of a communication model between a teach pendant and a controller according to an embodiment of the present invention.

Fig. 4 is a schematic diagram of the general hardware architecture of the welding robot control system in the embodiment of the present invention.

Fig. 5 is a diagram of the MVC pattern of the upper computer in the embodiment of the present invention.

FIG. 6 is a diagram of a lower computer software architecture according to an embodiment of the present invention.

Fig. 7 is a flowchart of an algorithm for planning the movement of the welding robot according to an embodiment of the present invention.

FIG. 8 is a schematic view of a straight line weld with pose transformation in an embodiment of the invention.

FIG. 9 is a schematic view of a circular arc weld in an embodiment of the present invention.

FIG. 10 is a schematic view of a round weld workpiece according to an embodiment of the present invention.

Fig. 11 is a schematic diagram of a cooperative welding mode and a welding effect in the embodiment of the invention.

FIG. 12 is a schematic diagram of the effect of swing welding according to an embodiment of the present invention.

Fig. 13 is a schematic diagram of the effect of laser tracking welding in the embodiment of the present invention.

Detailed Description

Various exemplary embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that: the relative arrangement of the components and steps, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise.

Meanwhile, it should be understood that the sizes of the respective portions shown in the drawings are not drawn in an actual proportional relationship for the convenience of description.

The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses.

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to specific embodiments and the accompanying drawings.

Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate.

In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.

In the first embodiment, as shown in fig. 1, the overall architecture of a welding robot control system is shown, except for a robot peripheral device (hereinafter referred to as peripheral device) and a body structure, the whole system is decomposed into three modules, namely an upper computer, a lower computer and hardware;

the upper computer is mainly responsible for man-machine interaction, a user can accurately control the robot to move in a control mode of a rocker and can also interact with the robot in a touch screen mode, and the upper computer is connected and communicated with the lower computer in an Ethernet mode;

the lower computer is composed of an ARM + FPGA SOC, logic control of the whole robot is carried out on an ARM layer, the logic control comprises communication, algorithm, process control and the like, the lower computer is a core part of the whole control system, and various interfaces are provided on the FPGA layer to carry out data interaction with a hardware layer;

the hardware part is mainly used for expanding pin addresses defined in the FPGA and butting with peripheral equipment through an expanded interface of the expansion board.

1.1 embedded processor type selection:

generally, the traditional embedded system architecture design has high production cost and is limited by the performance of PCB wiring and I/O pins, so the SoC FPGA architecture is adopted in the patent, as shown in fig. 2, that is, a novel SoC chip integrating an ARM processor and an FPGA on a single chip has the following advantages:

(1) the FPGA-based network interface system has the advantages of high-speed parallel processing and flexible customization of the FPGA, and also has the advantages of flexible control, graphical interface display and network transmission of the ARM processor.

(2) Compared with a processor and FPGA structure, the communication bandwidth and the communication efficiency between the processor and the FPGA are greatly improved. The SoC FPGA adopts an on-chip integration mode, the FPGA and the HPS system are integrated on the same chip, a data bit width of up to 128 bits is designed between the FPGA and the HPS system, the operating frequency reaches 200MHz, and the communication bandwidth and the communication efficiency between the FPGA and the HPS system are greatly improved.

(3) Users can customize the SoC system according to engineering requirements, select peripherals, a memory and interfaces, and can also embed own specific functions to design a processor with competitive advantages.

(4) The time to market of the product can be shortened by adopting the SoC FPGA, and the development time can be effectively shortened based on the development software of a Linux operating system in an ARM processor; the programmable logic advantage of the FPGA is fully exerted, and general hardware with competitive advantage is established.

The invention aims to develop economic welding robot control system hardware with complete functions, an Intel company provides two series of Arria V and Cyclone V for middle-end and low-end application, provides Arria 10 series for high-end application, and synthesizes SoC FPGA key characteristics listed in a table 2, wherein DE0-Nano-SoC of the Cyclone V series is selected as a system core board in the embodiment.

TABLE 2 SoC FPGA Key characteristics

Selecting a SoC FPGA of a Cyclone V SE 5CSEMA4U23C6N model as a core processor, wherein the SoC FPGA comprises three 50MHz clocks, 40K programmable logic units, 2460K embedded memories, 5 analog phase-locked loops (PLL), 2 hard disk controllers, 1 4-wire SPI interface and a USB-Blaster II interface; and the dual-core Cortex-A9 ARM core comprises 1GB DDR3 SDRAM and SD card capable of recording Linux system.

1.2 demonstrator (industrial android screen) selection

The WiFi performance of the Miezhi technology Y7P10 android screen selected in the embodiment is generally higher than that of other android screens, the Y7P10 android screen adopts a 4-core Cortex-A7 framework, and a CPU with a main frequency of 1.2 GHz. The welding robot system is characterized in that 12V power supply is adopted, an IPS capacitive touch screen with the standard size of 7 inches and the resolution ratio of 1024 x 600 is matched, 2 pieces of 512MB DDR3 share 1GB operation memory, 4 paths of RS-232 interfaces, 1 path of RS-485 interfaces, 4 paths of USB interfaces and one hundred mega Ethernet interfaces are included, a reliable and friendly human-computer interface can be completely provided, application programs can be taught and edited, and the setting of tool parameters, external axis parameters and external equipment parameters and the display of the state of a welding robot are realized.

1.3 welding machine model selection

Digital welders are becoming more and more widely used in the field of welding. The welding machine mainly realizes functions by software, and can integrate various welding functions. Compared with the traditional welding machine, the digital welding machine has higher reliability and stability, has the characteristics of safety and energy conservation, and is more suitable for automatic welding. The digitalized inversion welding machine is the mainstream direction of the future development of the welding machine, so the full-digital IGBT inversion multifunctional welding machine of the McGMite Artsen Plus series is selected, the specific model is Artsen Plus 500DR, when the welding machine is connected with a full-digital control wire feeder, three modes of direct current, pulse and double-pulse welding based on real-time energy control can be selected, and a special welding control mode can be customized.

1.4 driver model selection

The system adopts a pulse and direction control motor to operate, the welding gun load arranged at the tail end of the welding robot is small, the requirements on the moment and the load capacity of a driver are not high, but the welding robot with higher precision and design is expected, the rated power required by each axis of a control position is about 700W, and the rated power required by each axis of a control posture is 200W.

Based on the above conditions, the embodiment of the invention selects a loose (Panasonic) a4 series MCDJT3220 ac servo driver, which is an economical servo driver specially used for position control and suitable for motors with power of 50W-50KW, and mainly simplifies the functions of the driver.

The position control mode of the driver has three modes, firstly, an open-circuit command pulse is input to a collector, the frequency can reach 200KHz, and the minimum pulse width is 2.5 us; differential command pulse input, wherein the pulse frequency can reach 500KHz, and the minimum pulse width is 1 us; and thirdly, inputting a high-speed differential command pulse, wherein the maximum pulse width is 4MHz, and the minimum pulse width is 0.125 us.

1.5 communication mode selection

As shown in fig. 3, a communication model of the teach pendant and the controller is that the teach pendant in the teach pendant belongs to a mobile handheld device, and the mobility and flexibility of the teach pendant can be improved by adopting a wireless communication mode. In recent years, the wireless communication modes with wide application and promising development are shown in table 4:

TABLE 4 Wireless communication scheme

Because welding robot control system task is complicated, and the data of transmission are many, and with present wireless communication mode, wiFi covers extensively, does not have the position requirement to the teach box, and transmission rate is fast, and the technical development degree of difficulty is low, and the later maintenance cost is low, need not other expenses during the use. Therefore, the wireless communication of the welding robot control system in this embodiment adopts a WiFi mode, but in order to prevent the communication from being affected in a strong interference environment, two communication modes, namely RS485 and network cables, are also designed in some embodiments.

1.6 hardware architecture design

The control system hardware with high reliability, simple operation and good man-machine interaction is designed by taking DE0-Nano-SoC V5 CSEMA4U23C6N as a control core of the control system hardware and taking a Mitsui science and technology Y7P10 Android screen as a demonstrator, and adopting Wi-Fi, 485 and network cable modes for communication between the controller and the demonstrator, and combining an embedded type, an Android system, a Wi-Fi technology and a serial port communication technology, so that the overall architecture of the system hardware is determined, and the figure 4 shows.

Because the android industrial screen does not have extra pins and can not be directly expanded, the rocker sampling plate is made, the rocker data is transmitted to the demonstrator through the RS-232 serial port, and the rocker data is transmitted to the core board to control each shaft of the robot to feed after conversion processing.

1.7 Upper computer System software design

The upper computer is developed by using Android, an Android industrial screen and a rocker peripheral are used as hardware bases, the upper computer program can respond to touch operation of a user, an operation mode of the rocker is provided, and the user can control single-axis motion of the robot more conveniently.

Fig. 5 shows an MVC pattern diagram of an upper computer, and the MVC design pattern is combined to divide the model layer of the upper computer into the parts, serial port communication and data processing between an android screen and a rocker, Socket communication data processing between a demonstrator and a lower computer, parameter setting of robot parameters and speed, process and the like.

The viewing layer can be mainly divided into 5 kinds of interfaces: selecting the type of the robot, a welcome interface, a main interface, a teaching interface, a welding/grabbing interface, a file management interface and a parameter setting interface; in order to make full use of the interface space on the parameter setting interface, fragment in android is adopted for design, and the parameter setting is divided into 8 fragment parts including common parameters, structural parameters, zero-return measurement, calibration of a tool coordinate system, speed limit setting, input and output ports, alarm setting and a control system.

The control layer mainly comprises user button event monitoring and rocker serial port event monitoring, the view is updated in time by monitoring the movement of a user touch motor or a rocker, and corresponding models are controlled to realize corresponding functions.

1.8 demonstrator Main interface function

The human-computer interaction interface is an important part of user experience, and according to the steps and actual requirements of teaching reproduction, the demonstrator should comprise the following functional interfaces:

firstly, the robot is calibrated by pulse equivalent, so that a setting interface of the pulse equivalent of each axis is required to be added on a parameter setting interface; after the calibration is finished, related parameters of the robot are required to be set, wherein the related parameters comprise speed, acceleration and welding process selection; the zero returning operation of the robot can be carried out according to the appointed pose after the parameter setting is finished; after zero return is completed, the robot can be taught and moved; finally, in order to conveniently manage the teaching files, a file management function module needs to be designed.

1.9 design of lower computer software architecture

The lower computer consists of an ARM hard core and an FPGA hard core, a Linux system is embedded in the ARM, a C + + program is developed to communicate with the upper computer, related algorithms such as robot track planning and attitude planning are provided, and all service requests are taken charge of.

The lower computer software architecture diagram is shown in fig. 6, the lower computer system is located in the middle layer of the whole control system, mainly responses to user instructions and feedbacks to external signals and data, and the program is composed of 6 threads, namely a data receiving thread, a data analyzing thread, a motion thread, a signal monitoring thread, a TCP heartbeat thread and a main monitoring thread.

The data receiving thread mainly receives data issued by an upper computer, only divides the received data and judges whether the data accord with protocol rules or not. Each data sequence is composed of an instruction word, a length, data and a check bit, and the data length and the check bit are verified in a data receiving thread. And if the verification is passed, putting the data into a message queue, and waiting for the data analysis thread to analyze. And if the verification fails, feeding back an error to the upper computer, requesting to retransmit the instruction and reporting the error to the user.

The motion thread judges each motion state mark of single-axis motion, teaching motion, automatic welding and the like in a polling mode, and if one motion mark is changed, the thread responds to the motion, sends corresponding pulses to the FPGA interface and further drives the robot to move.

The signal monitoring thread also exists in the system in a polling mode, the FPGA provides an address interface of each IO port, and signals of each sensor are read through the address interfaces. When an external signal is triggered, the signal monitoring thread returns different sensor data to the upper computer, and a user judges the current motion state of the robot through the display of the upper computer on the state of the sensor. The signal monitoring thread can also obtain offset data returned by the welding seam tracking system through a 232 or 485 interface provided by the FPGA, and the attitude is corrected in real time by the lower computer.

The TCP heartbeat thread is mainly used for ensuring that an upper computer and a lower computer can timely acquire the connection state of a current network, the upper computer sends a heartbeat protocol to the lower computer at regular intervals, and the lower computer activates a heartbeat mark after receiving the protocol. And the TCP heartbeat thread detects a heartbeat mark once every three heartbeat periods, if the heartbeat mark is not activated, the network is disconnected, and all the motions are stopped by the lower computer, so that the collision is avoided.

The main monitoring thread is used as the main thread of the whole lower computer, and the thread always exists in the system from the system power-on to the power-off. The main function of the thread is to ensure that the upper computer and the lower computer simultaneously carry out system initialization, and communication connection needs to be reestablished and the lower computer needs to be reinitialized each time a user restarts an upper computer program. And the main monitoring thread mainly monitors the Socket communication state, and if a new connection request exists, the old Socket connection is ended, the system resources are released, the whole lower computer control system is reset, and the upper computer and the lower computer are ensured to be initialized at the same time.

As shown in fig. 7, the motion algorithm of the robot is mainly implemented in an automatic welding module, and after an original joint angle is obtained through data analysis and thread analysis, a target joint angle sequence obtained through interpolation is obtained through trajectory planning and speed planning, the target joint angle sequence is converted into a pulse number sent by each axis at each moment and sent to an FPGA, and then a motor of each axis is driven to rotate to complete trajectory motion; the welding gun calibration algorithm reads the motion amount of each axis through a signal monitoring thread, calls a welding gun calibration algorithm interface, completes the calculation of a calibration result, and finally transmits the result back to an upper computer for data storage and display.

1.10 Environment building method

The lower computer core control system software builds an embedded Linux development environment by using eclipse, realizes system-level operation by calling Linux thread resources and Socket resources, uses C + + for development in order to ensure the running speed and stability of a program, and introduces an Eigen matrix library for matrix operation.

The lower computer program downloads and debugs the program through the Ethernet, and the upper computer needs to ensure that the IP address is in the same interval.

When the ARM-DS5 integrated system is installed, the system is provided with a C + + compiler of Linux, so that the Linux compiler is selected to compile programs when a project is built. The Linux system on the SOC is a small cut Linux system which is burned on a Cortex M3 chip and supports various interfaces such as an Ethernet interface, a USB and the like, and Win32Disk Imager is used for burning and recording the Linux system on an ARM chip of a lower computer.

In this embodiment, the main data communication protocol of the robot welding control system is the TCP protocol, which can avoid the possibility of packet loss from the bottom layer to some extent, but the influence factors of the communication stability are many-sided. Therefore, the system writes a watchdog thread in a software layer to ensure the real-time accessibility of message sending, and is realized by detecting the alarm mark once every 1s interval.

In the embodiment, the robot welding control system supports a power failure protection function, an application system cannot be recovered due to important data loss caused by instantaneous undervoltage or power failure, a power failure protection circuit is designed, and the abnormal power failure processing capacity of the system is enhanced. And designing I/O interfaces for state detection and emergency treatment, including limit detection, drive alarm signal detection, emergency stop and the like.

In the embodiment, the robot welding control system supports a gun cleaning station, so that sticking blockage generated in the working process of the welding robot and shallow objects in a gas protection sleeve of a welding gun are cleaned, the gas is ensured to be smooth for a long time, and the quality of a welding seam is improved; the wire feeder is supported, the wire feeding precision is ensured, and the utilization rate of welding wires is improved; supporting the external shaft linkage coupling processing, sometimes need to cooperate with two axis displacement body, so design 8 axle drives.

The above description is only exemplary of the present invention and should not be taken as limiting the invention, as any modification, equivalent replacement, or improvement made within the spirit and scope of the present invention should be included in the present invention.

The implementation effect after the implementation of the technical scheme is as follows:

the invention mainly tests the function test of the rectangular coordinate type welding robot, is one of the most basic and important tests of the whole system, and mainly verifies the track planning algorithm. The cantilever type welding robot is used as a small platform for testing, has a smaller structure, but has the same operation effect as the coordinate type welding robot.

The coordinate type welding robot has good welding effect on a horizontal straight line welding line of a welding workpiece, the welding track is continuous, the phenomena of broken welding and non-uniformity are avoided, and the space straight line algorithm and the acceleration and deceleration algorithm are proved to be basically stable.

As shown in fig. 8, it is shown that the straight-line weld with posture change in the welding process is welded more uniformly at the over-weld joint, and no surfacing and lack of welding occur, which proves that the speed planning algorithm between multiple sections of welds can obtain a good application effect in an actual field.

As shown in fig. 9, an arc is also one of the most common teaching shapes in an actual welding field, and three-point arc welding can achieve a good practical application effect, which proves that the arc trajectory planning algorithm is successfully applied in a scene of welding such a large arc.

As shown in fig. 10, the welding effect of the full-circle weld obtained by three-point teaching is shown, and welding defects such as broken welding do not occur in the finished weld, which indicates that the three-point teaching full-circle trajectory planning algorithm can meet the welding requirements of the basic circular weld.

As shown in fig. 11, a cooperative welding mode and a welding effect are provided, and for a welding scene where an intersecting line and a workpiece need to be fixed, a robot and a positioner are often required to perform cooperative welding. The welding robot and the positioner move cooperatively, so that the welding of a singular welding seam can be finished, the stability during welding can be improved to a certain extent, and the welding quality is improved. The circular welding seam of spot welding through the positioner has stronger stereovision, has great promotion in welding quality.

As shown in fig. 12, for the seam welding with a large gap or a large thickness, a pendulum welding function is often used to improve the welding quality. The welding amplitude can be enlarged through swing welding, and even the effect of fish scale welding can be achieved. The swing welding motion is completed through the swing shaft of the rectangular coordinate type welding robot, so that the usability is high, and the use cost of the whole robot is saved to a great extent.

As shown in fig. 13, the schematic diagram of the laser tracking welding effect is shown, the welding seam obtained by tracking is consistent with the actual welding seam, and the welding of the straight welding seam is just completed, which proves that the welding seam tracking trajectory planning algorithm can complete the compensation of the measured deviation of the welding seam tracker.

It should also be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in the process, method, article, or apparatus that comprises the element.

Claims (10)

1. The utility model provides a coordinate formula welding robot control system, includes host computer, next machine, hardware module and robot peripheral equipment, its characterized in that:

the upper computer is connected with the lower computer and is used for inputting and/or outputting a motion control command;

the lower computer is used for operating a control algorithm and generating control logic for controlling the welding machine;

and the hardware module is used for receiving the control logic through an expansion board interface and transmitting the control logic to the robot peripheral equipment.

2. The coordinate welding robot control system of claim 1, wherein the system architecture of the lower computer is as follows:

an SoC FPGA architecture or an ARM + FPGA architecture, the SoC FPGA architecture being an SoC chip integrating an ARM processor and an FPGA on a single chip.

3. The coordinate welding robot control system of claim 1, wherein the upper computer comprises:

the demonstrator is developed by using an Android system and is used for realizing man-machine interaction, teaching, editing application programs, setting control equipment parameters and displaying the state of the current controlled object.

4. The coordinate welding robot control system of claim 3, wherein the upper computer further comprises:

and the remote rod control is used for sending a control instruction to the demonstrator through a serial port on the remote rod sampling plate.

5. The coordinate welding robot control system according to any one of claims 3 or 4, wherein the teach pendant is further configured to convert the control command and send the converted control command to the lower computer.

6. The coordinate welding robot control system of claim 1, wherein the robot peripheral device comprises:

the welding machine comprises a digital welding machine, a shaft motor driver, a position sensor, a welding seam tracking device, a wire feeder and a gun cleaning station;

the digital welding machine is connected with the hardware module through a first IO expansion interface;

the shaft motor drive receives the pulse differential signal sent by the hardware module and drives the shaft motor to operate;

the position sensor is connected with the hardware module through a second IO expansion interface;

the welding seam tracking device is in communication connection with the hardware module through an expansion serial port on the expansion board;

the wire feeder is connected with the hardware module through a third IO expansion interface or is in communication connection with the hardware module through the expansion serial port;

and the gun cleaning station is connected with the hardware module through a fourth IO expansion interface, or is in communication connection with the hardware module through the expansion serial port.

7. The coordinate welding robot control system of claim 6, wherein the axis motor drive is an 8-axis drive.

8. The coordinate welding robot control system of claim 6, wherein the upper computer further comprises:

the software control layer is used for monitoring a user button event and a rocker serial port event so as to obtain monitoring information;

and the software view layer is used for updating the view after receiving the monitoring information and inputting a control instruction.

9. A coordinate type welding robot motion control method for realizing the coordinate type welding robot control method when a coordinate type welding robot control system according to any one of claims 1 to 8 is operated, the coordinate type welding robot control method comprising:

analyzing the thread data to obtain an original joint angle of the demonstrator;

planning a motion track and a motion speed to obtain an interpolated target joint angle sequence;

converting the target joint angle sequence into the pulse number sent by the shaft of the shaft motor at each moment;

sending the pulse number to an FPGA to drive a motor to rotate;

monitoring the thread while the motor rotates to obtain the amount of motion of the shaft motor;

and transmitting the motion amount back to an upper computer for data storage and display.

10. Coordinate welding robot, characterized in that it comprises a robot body, and a coordinate welding robot control system according to any of claims 1-8 for controlling the robot body to perform welding.

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