1 Robot control system
1.1 System control requirements
The task of the handling manipulator is to send the workpiece processed on the left station to the right station. It is known that the workpiece to be handled is directly below the initial position of the manipulator. The manipulator has the following control requirements:
(1) The manipulator is at the initial position, after pressing the start button, the manipulator moves down to the workpiece → clamps the workpiece → lifts the workpiece → moves right to the next station above → moves down to the designated position → puts down the workpiece → moves up → Move left to return to the original position. This process is repeated cyclically.
(2) If the manipulator presses the stop button during the movement, the manipulator will not stop immediately, nor will it automatically reset, but will continue to work until it completes the current cycle operation and returns to the original position, and then stops and does not cycle again. If the emergency stop button is pressed, the manipulator stops at the current position. After the emergency stop is released, press the reset button to reset the manipulator and stop at the initial position to wait for the operation to resume.
1.2 System Hardware Configuration
(1) Selection of the control system. At present, there are many kinds of PLCs imported from abroad and assembled and developed in China in the domestic market. Therefore, PLC series have different standards, different functions, and different prices. Taking into account the cost performance of PLC, the ability to adapt to the load and the adaptability of school teaching, PACSystems RX3i series PLC products and QP Control 6″ TFT (IC754Cxx06Cxx) touch screen are selected. .Control software adopts Proficy Machine Edition 6.0 of GE's integrated development environment, which integrates Proficy View (touch screen), Logic Developer-PLC (PLC/PAC programming), Logic Developer-PC (PC-based control system) in one development environment. Programming and running debugging) and Proficy Motion Developer (motion control programming) programming interface, the switching of programming interface can be realized by simply clicking Apply Themes in the drop-down menu of Window in the menu bar. Proficy ME software platform has excellent performance on a variety of hardware. portability [3].
(2) The hardware composition of PLC system. The hardware structure of the PLC system mainly includes: RX3i programmable controller CPU module (IC695CPU310), 12-slot backplane (IC695CHS012), DC 24V single-width power supply module (IC695PSD040), Ethernet communication module (IC695ETM001), 32-point control Command input module (IC694MDL655), 32-point control command output module (IC694MDL754) [4]. Its hardware structure is shown in Figure 2.
1.3 System software design
(1) Address allocation of the system. According to the control requirements of the manipulator, there are 4 button input signals in this control system, which respectively perform the functions of start, stop, emergency stop and reset; 4 position detection sensors are required, which respectively perform the left limit, upper limit, lower limit and right limit. Bit function; There are 5 output signals, which respectively perform the functions of moving down, clamping, rising, moving right and moving left of the manipulator. The I/O assignment of the system is shown in Table 1.
(2) The design of the touch screen man-machine interface consists of the following two parts. The first part: monitoring interface design. The touch screen of the system selects IC754VSL12CTD with a resolution of 800×600 pixels. The operating system of the touch screen is Microsoft Windows CE. NETFM, which is stored in 16MB flash memory, is copied to dynamic memory when used, and the operating system automatically starts running after power-on or restart of the touch screen. Since GE has integrated the touch screen Quick panel View programming software with Proficy MachineEdition software, all interface products can use the same software package for software programming, which includes a wealth of tools such as configuration, components, drawing and scripting. , so complex monitoring screen development can be completed in a relatively short time. After completing the overall screen production and script programming, download the software compiled in Proficy Machine Edition to the PLC through the Ethernet communication module of the PLC through a self-adaptive, half-duplex or full-duplex network card port on the touch screen. In the touch screen, communication with PLC and human-computer interaction are realized at the same time. The system touch screen monitoring screen.
A simple schematic diagram of the manipulator is drawn in the monitoring screen, and four input buttons, four limit switch indicators, and two clamp and release indicators are designed. The up, down, left and right actions of the manipulator can be controlled from Visible on the screen. There are also two status indicators in the screen, which represent the state of the manipulator running and stopping. When the manipulator is in the state of running and stopping, they will give corresponding indications. Part II: Animated connection of variables. In this control system, the corresponding buttons, indicator lights and the movement of the manipulator in the touch screen monitoring picture are connected with the variables in the PLC, so that the monitoring picture can be moved according to the action requirements. The buttons on the touch screen and the indicator lights of the limit switch are connected with the ladder diagram program through the intermediate relay, and the four action variables of up, down, left and right of the manipulator are connected with the output relay and the corresponding script program realizes the animation function. The animation connection of the button (take the start button as an example) needs to be configured by Touch and Color; the animation connection of the indicator light needs to be configured by Color and script program; the movement of the robot arm needs to be configured by Size, Position and script program. The configuration method takes the start button touch dynamic configuration as an example,
The script program of the moving animation of the robot arm and the state change of the position sensor indicator light (taking the robot arm moving down and the lower limit sensor indicator light as an example) is as follows:
IF Targetl.Q00001>0
xiajiang:=xiajiang+10
ENDIF
IF xiajiang>50
Targetl.M00007:=1
ENDIF
IF Targetl.Q00003>0
Targetl.M00007:=0
ENDIF
(3) PLC software programming. The control system software adopts ProficyME 6.0 programming, Proficy ME 6.0 software is a visual development tool for GE PLC programming under the Windows operating system, using Logic Developer-PLC can be used to develop control programs on a personal computer, and through Ethernet or serial port to the PLC.
2 Software and hardware joint debugging of control system
Through the connection (Online/Offline) of the Proficy Machine Edition programming interface, establish the connection between the PC and the PAC and download it, and turn the dial switch on the CPU310 to the RUN OUTPUT DISABLE position, and observe whether the running result of the program output is correct. If the design is correct, turn the toggle switch to RUN I/O ENABLE. Right-click the target object of the touch screen, press the left key to select Download and Run from the drop-down menu, download the touch screen operation screen and script program to the touch screen, click the input button on the screen, modify the program and monitor screen until the touch screen screen is displayed to observe the operation of the manipulator until the process meets the control requirements of the control system.
3 Conclusion
The design proposes to apply the touch screen to the PLC control system of the manipulator. The software and hardware design of the whole control system and the debugging of the system can realize PLC control of the manipulator on the touch screen, and truly show the working process of the manipulator as the controlled object in the control system. The practical application proves that the system design is reasonable and the simulation effect is realistic, which is helpful to improve students' PLC programming ability in industrial control and achieve the purpose of enriching students' engineering practice experience. It can be promoted in college teaching and has strong practicability.
Application and Design of Touch Screen in Manipulator Control System
2022 07/19