CN103021228A - Traffic experiment system based on touch screen and programmable logic controller (PLC) and control method thereof - Google Patents

Abstract

The invention discloses a traffic experiment system based on touch screen and PLC, including touch screen, PLC (programmable logic controller), traffic lights, serial communication line and DC power supply, PLC is connected with touch screen through serial communication line, PLC and traffic The lamps and lanterns are electrically connected, and each part of the system is powered by a DC power supply. In the traffic experiment system based on the touch screen and PLC of the present invention, the operation data of the PLC is displayed on the traffic light fixture through the wire, and the operation data and the state of the traffic light are reflected on the touch screen through the serial communication line at the same time, and the learners input on the touch screen Instructions can also be transmitted to the PLC through the serial communication line to control its operation mode. The instructions include traffic light time setting, day mode, night mode and express traffic; this system can enable learners to creatively design touch screen interface and ladder diagram method , Effect images, powerful functions, expand the experimental content, improve the teaching effect, but also stimulate students to learn the fun of PLC controllers.

Description

Traffic experiment system and its control method based on touch screen and PLC

technical field

The invention relates to a traffic experiment system based on a touch screen and a PLC (programmable logic controller) and a control method thereof, belonging to the field of electrical and electromechanical technology.

Background technique

At present, many colleges and universities have opened PLC (programmable logic controller) courses in electrical and electromechanical majors, and generally still focus on book teaching. Although some use multimedia courseware to assist teaching, students still feel that the content is abstract and difficult to understand. Especially in the practical link, PLC teaching is even more difficult, and it does not allow students to achieve the purpose of applying what they have learned. Controlling traffic lights is a typical application of PLC. Some school curriculum designs use PLC to control light-emitting diodes to simulate the simple working method of traffic lights, which lacks some vivid effects, and the realized functions are fixed and single, and cannot be multi-functional and multi-mode in real time. Controlling the working mode of light-emitting diodes failed to stimulate students' interest and creativity. To this end, students need a new traffic experiment system, which enables students to design and verify their own PLC topics, so as to change passive and boring learning into active and creative learning.

Moreover, the number of vehicles has increased rapidly in recent years, while urban road construction and traffic management are relatively lagging behind. People and vehicles compete for roads, road congestion, congestion, traffic accidents, etc. often occur, and urban traffic problems have attracted more and more attention. At present, my country's urban traffic light system is relatively simple, and the traffic lights at intersections are basically fixed timed. The traffic department determines a fixed value as the working hours of traffic lights according to the statistical value of road traffic flow by statisticians, but it cannot be effective. Functional, multi-mode real-time control of how traffic lights work. According to the existing PLC traffic experiment system, it cannot stimulate students' interest in traffic light control and thinking and exploration of traffic intelligent management.

Today, the touch screen is a new type of programmable control terminal, a new generation of high-tech human-machine interface products, suitable for on-site control, high reliability, simple programming, and convenient use and maintenance. When there are many process parameters and human-computer interaction is required, the use of the touch screen can greatly enhance the automatic control function of the entire production. It has been well applied in industry and some electrical equipment, but it has not been applied in actual traffic control and PLC traffic experiments.

Contents of the invention

Purpose of the invention: In order to overcome the deficiencies in the prior art, the present invention provides a traffic experiment system based on touch screen and PLC, which can help students deeply understand the working principle and application method of PLC, stimulate students' interest and creativity, and encourage students to understand The thinking and exploration of traffic intelligent management assists teachers to better complete teaching tasks.

Technical solution: a traffic experiment system based on a touch screen and PLC, characterized in that: the traffic experiment system is composed of a touch screen, PLC, traffic lights, serial communication lines and DC power supply, and the PLC is connected to the touch screen through a serial communication line , The PLC is electrically connected to the traffic light lamp, and the touch screen, PLC, traffic light lamp and serial communication line are all powered by a DC power supply.

The touch screen is TPC7062K.

The PLC is Siemens S7-200 series PLC.

The traffic lights are composed of 12 industrial signal lights, including 4 red lights, 4 green lights and 4 yellow lights, which are arranged in the same arrangement as the actual traffic lights.

The serial port communication line is an RS-485 communication bus.

The DC power supply is 24V DC power supply.

A control method of a traffic experiment system based on touch screen and PLC, comprising the following steps:

Step (1): Initialize, set traffic light time and clock time on the touch screen;

Step (2) - main method: automatically select day mode and night mode according to the clock time. In day mode, the red light, green light, and yellow light are normally displayed in turn according to the set time; in night mode, only the yellow light flashes, and the red light and Green light doesn't work.

If there is an urgent vehicle to pass the traffic light quickly, it also includes step (3)-urgent vehicle passage sub-method: if there is an urgent vehicle to quickly pass the traffic light, the emergency vehicle passage sub-method is called through the buttons on the touch screen to control the working mode of the traffic light to achieve emergency The purpose of driving ahead.

The step (2) - the main method specifically refers to:

2a): Set the clock time and traffic light time through the input box control on the touch screen. After normal operation, the clock time is transmitted to the register in the PLC in real time, and the set traffic light time data is transmitted to the control traffic light in the PLC method On the timer of the running time;

2b): According to the clock time in the register, the PLC judges whether it is between 5 o'clock and 22 o'clock, if yes, run the traffic light day mode; if not, jump to the traffic light night mode;

2c): According to whether the emergency vehicle pass button is pressed on the touch screen, judge whether to carry out the emergency vehicle pass, if not, continue to run the main method; if yes, call the express vehicle pass sub-method;

2d): If not, judge whether the step is over; if not, go to 2b); if yes, end.

The step (3)-the emergency vehicle passage sub-method specifically refers to:

3a): According to the operation of the buttons on the touch screen, judge whether the north-south road is open, if yes, the method of entering the north-south road; if not, the method of turning to the east-west road;

3b): Judging whether to return to the main method, if not, continue to run the next step of the sub-method; if yes, return to 2b) of the main method;

3c): According to the operation of the buttons on the touch screen, it is judged whether the east-west road is passing, if yes, the method of entering the east-west road; if not, the method of turning to the north-south road;

3d): Determine whether to return to the main method; if not, go to 3a); if yes, return to 2b) of the main method.

The beneficial effects are: the traffic experiment system and its control method based on the touch screen and PLC provided by the present invention are basically the same as the actual traffic system principle, adopt the touch screen and PLC control technology, make a friendly man-machine interface, monitor the traffic lights, and realize The functions of traffic light time setting, daytime mode, nighttime mode and express traffic allow students to experience the practical application of PLC in traffic control; comprehensive training for students, including traffic light experimental system design and wiring training, PLC control system Design and hardware wiring training, PLC programming training, touch screen interface design and system software and hardware debugging training, stimulate students' interest and creativity, stimulate students' interest in traffic light control and thinking and exploration of traffic intelligent management, and be proactive To learn about PLC knowledge. the

Description of drawings

Fig. 1 is a structural representation of the present invention;

Fig. 2 is a flow chart of the control method of the present invention.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings.

As shown in Figure 1, it is a kind of traffic experiment system based on touch screen and PLC, which is composed of touch screen 1, PLC2, traffic light lamps and lanterns 3, serial port communication line 4 and DC power supply 5, and described PLC2 communicates with touch screen 1 through serial port communication line 4 Connection, PLC2 is electrically connected with traffic light fixture 3, and touch screen 1, PLC2, traffic light fixture 3 and serial port communication line 4 are all powered by DC power supply 5; Described touch screen 1 is TPC7062K; Described PLC2 is the S7-200 series of Siemens PLC; the traffic light fixture 3 is composed of 12 industrial signal lights, 4 red lights, green lights, and yellow lights, which are the same as the actual traffic lights; the serial communication line 4 is a RS-485 communication bus; the DC The power supply 5 is a DC power supply of 24V.

Further, the COM2 port of the PLC is connected to the negative pole of the DC power supply 24V, the PORT1 port of the PLC is connected to the serial port (DB9) of the touch screen through the serial port communication line RS-485, and the output port Y0 of the PLC is connected to the traffic light lamp One end of L0 and L6, the output port Y1 of the PLC is connected to one end of L1 and L7 of the traffic light lamp, the output port Y2 of the PLC is connected to one end of L2 and L8 of the traffic light lamp, and the output port Y3 of the PLC One end of L3 and L9 of the traffic light fixture is connected, the output port Y4 of the PLC is connected with one end of L4 and L10 of the traffic light fixture, and the output port Y5 of the PLC is connected with one end of L5 and L11 of the traffic light fixture. The other terminals of the traffic light lamps L0, L1, L2, L3, L4, L5, L6, L7, L8, L9, L10, L11 are connected to the positive pole of the DC power supply 24V.

As shown in Figure 2, it is a control method for a traffic experiment system based on touch screen and PLC, comprising the following steps:

Step (1): Initialize, set traffic light time and clock time on the touch screen;

Step (2) - main method: automatically select day mode and night mode according to the clock time. In day mode, the red light, green light, and yellow light are normally displayed in turn according to the set time; in night mode, only the yellow light flashes, and the red light and Green light doesn't work.

If there is an urgent vehicle to pass the traffic light quickly, it also includes step (3)-urgent vehicle passage sub-method: if there is an urgent vehicle to quickly pass the traffic light, the emergency vehicle passage sub-method is called through the buttons on the touch screen to control the working mode of the traffic light to achieve emergency The purpose of driving ahead.

The step (2) - the main method specifically refers to:

2a): Set the clock time and traffic light time through the input box control on the touch screen. After normal operation, the clock time is transmitted to the register in the PLC in real time, and the set traffic light time data is transmitted to the control traffic light in the PLC method On the timer of the running time;

2b): According to the clock time in the register, the PLC judges whether it is between 5 o'clock and 22 o'clock, if yes, run the traffic light day mode; if not, jump to the traffic light night mode;

2c): According to whether the emergency vehicle pass button is pressed on the touch screen, judge whether to carry out the emergency vehicle pass, if not, continue to run the main method; if yes, call the express vehicle pass sub-method;

2d): If not, judge whether the step is over; if not, go to 2b); if yes, end.

The step (3)-the emergency vehicle passage sub-method specifically refers to:

3a): According to the operation of the buttons on the touch screen, judge whether the north-south road is open, if yes, the method of entering the north-south road; if not, the method of turning to the east-west road;

3b): judge whether to return to the main method; if not, continue to run the next step of the sub-method; if yes, return to 2b) of the main method;

3c): According to the operation of the buttons on the touch screen, it is judged whether the east-west road is passing, if yes, the method of entering the east-west road; if not, the method of turning to the north-south road;

3d): Determine whether to return to the main method, if not, go to 3a); if yes, return to 2b) of the main method. the

For completing the present invention, concrete preparatory work and setting are as follows:

Install the PLC programming software STEP 7 - MicroWIN on the PC. After the installation is successful, open the software and set the communication parameters. The communication address of PC/PPI is set to 0, the interface uses COM1, and the transmission baud rate uses 9.6Kbps. According to the function to be realized, draw the program flow chart, then write the ladder diagram, and finally download it to the PLC through the serial communication line, and set the PLC to the RUN state.

Install the configuration software MCGS of the touch screen on the PC. After the installation is successful, open the software, create a new project, select the TPC type as TPC7062K according to the selected touch screen, and add a general serial port parent device in the device window, and then add a child device That is Siemens S7-200PPI, and modify the serial port number to achieve normal data transmission, add the variable name used in the experimental system, and set the corresponding type of the variable. The port and type of the variable are consistent with the variable type in the PLC program. Under the user window, according to the PLC ladder diagram, select the appropriate control in the configuration toolbox, after continuous modification and improvement, it can realize the effect of vivid interface image, powerful and perfect function. Finally, it is downloaded to the touch screen through a dedicated data cable.

After the software and hardware are completed, the software and hardware of the experimental system are uniformly debugged. According to the working state of the traffic light, the monitoring of the STEP7 programming software and the display data and effects of the touch screen, check and modify the hardware system, check and modify the ladder diagram program, and check and modify the touch screen controls, and finally complete the experimental system.

The above is only a preferred embodiment of the present invention, it should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, some improvements and modifications can also be made, and these improvements and modifications are also possible. It should be regarded as the protection scope of the present invention.

Claims (10)

1. traffic experimental system based on touch-screen and PLC, it is characterized in that: described traffic experimental system is comprised of touch-screen, PLC, traffic lights light fixture, serial port communication line and direct supply, described PLC is connected with touch-screen by serial port communication line, PLC is electrically connected with the traffic lights light fixture, and touch-screen, PLC, traffic lights light fixture and serial port communication line are by DC power supply.

2. the traffic experimental system based on touch-screen and PLC according to claim 1, it is characterized in that: described touch-screen is TPC7062K.

3. the traffic experimental system based on touch-screen and PLC according to claim 1, it is characterized in that: described PLC is the PLC of the S7-200 series of Siemens.

4. the traffic experimental system based on touch-screen and PLC according to claim 1, it is characterized in that: described traffic lights light fixture is comprised of 12 industrial signal lamps, and each 4 of red lights, green light, amber light are arranged evenly identical with the actual traffic lamp.

5. the traffic experimental system based on touch-screen and PLC according to claim 1, it is characterized in that: described serial port communication line is the RS-485 communication bus.

6. the traffic experimental system based on touch-screen and PLC according to claim 1, it is characterized in that: described direct supply is direct supply 24V.

7. the control method of each described traffic experimental system based on touch-screen and PLC according to claim 1-6 may further comprise the steps:

Step (1): initialization arranges the traffic lights time and clock time in touch-screen;

Step (2)-main method: automatically select day mode and Night according to clock time, under the day mode, red light, green light, amber light normally show in turn according to setting-up time; Under the Night, only have the amber light flicker, red light and green light are not worked.

8. the control method of the traffic experimental system based on touch-screen and PLC according to claim 7, it is characterized in that: if there is anxious car will pass through rapidly traffic lights, also comprise step (3)-anxious car submethod that passes through: if there is anxious car will pass through rapidly traffic lights, button by touch-screen calls the current submethod of anxious car, the working method of control traffic lights reaches the purpose that anxious car is gone ahead of the rest.

9. the control method of the traffic experimental system based on touch-screen and PLC according to claim 8, it is characterized in that: described step (2)-main method specifically refers to:

2a): by the input frame control on the touch-screen, set clock time and traffic lights time, after the normal operation, clock time is real-time transmitted to the register among the PLC, and the traffic lights time data of setting is transferred on the red greenish-yellow lamp of control in the PLC method timer of working time;

2b): PLC judges whether between 5 o'clock to 22 o'clock according to the clock time in the register, if so, moves the traffic lights day mode; If not, jump to operation traffic lights Night;

2c): whether press according to the current button of anxious car on the touch-screen, judge whether to carry out anxious car and pass through, if not, continue the main method of operation; If so, call the current submethod of anxious car;

2d): if not, whether determining step finishes again; If not, forward 2b to) locate; If so, finish.

10. the control method of the traffic experimental system based on touch-screen and PLC according to claim 9, it is characterized in that: the current submethod of described step (3)-anxious car specifically refers to:

3a): according to the operation of button on the touch-screen, judge whether that the road, north and south is current, if so, enter the current method in road, north and south; If not, forward the current method in thing road to;

3b): judge the no main method that turns back to, if not, continue next step of operation submethod; If so, turn back to the 2b of main method) locate;

3c): according to the operation of button on the touch-screen, judge whether that the thing road is current, if so, enter the current method in thing road; If not, forward the current method in road, north and south to;

3d): judge whether to turn back to main method; If not, forward 3a to) locate; If so, turn back to the 2b of main method) locate.

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