With the increasing number of motor vehicles in cities, many big cities, such as Beijing, Shanghai and Nanjing, have experienced traffic overload. Therefore, since the late 1980s, these cities have successively built urban expressways, which have effectively improved the traffic conditions in the initial stage of expressway construction. However, with the rapid growth of traffic volume, the expressway lacks systematic research and control, and the expressway has not fully played its expected role. The structural characteristics of urban expressways also determine that the traffic conditions of urban expressways are bound to be restricted by the traffic conditions at the junction of expressways and ordinary roads. Therefore, how to use appropriate control methods to maximize the use of expensive urban expressways and alleviate traffic congestion between main roads and ramps, urban areas and surrounding areas has increasingly become the main problem to be solved by traffic management and urban planning departments. Therefore, the author has conducted in-depth research. This paper analyzes and discusses the circuit principle, design calculation and experimental debugging of the urban and rural traffic signal lamp simulation control system.
There are many control methods to realize intersection traffic light system, which can be realized by standard logic devices, programmable controller PLC, single chip microcomputer and other schemes. Among them, the realization of the circuit with standard logic devices is greatly influenced by logic devices such as gate circuits, and the debugging work is extremely difficult. The author is not very familiar with the design and development system with single chip microcomputer. Therefore, in the end, the author chooses to use programmable controller PLC to realize the design of system functions and complete the design task.
Keywords: PLC traffic light program report design
Task requirements:
1. Traffic traffic light control system
The start-stop control of 1. 1 The signal lamp is controlled by the start switch. Turn on the start switch, and the traffic signal lamp system, pedestrian signal lamp system and electronic police system will start to work. The red light for north-south traffic will light up first, and the green light for east-west traffic will light up. East-west pedestrian traffic red light, north-south pedestrian traffic green light; Loop control according to rules. When the start switch is turned off, the traffic signal system, pedestrian signal system and electronic police system stop working.
1.2 The north-south traffic red light is on for 60 seconds, and the east-west traffic red light is on for 60 seconds. Enter the next cycle.
1.3 When the north-south traffic red light is on, the east-west traffic green light is on for 25 seconds and then goes out. Then the east-west traffic yellow light flashes for 5 seconds and then goes out. Then the east-west traffic red light turns on, and the north-south turn green light goes out after 25 seconds. Enter the next cycle.
1.4 when the east-west traffic red light is on, the north-south traffic green light is on for 25 seconds and then goes out; Then the north-south traffic yellow light flashes for 5 seconds and then goes out. Then the north-south traffic red light turns on, the east-west turn green light turns on for 25 seconds, flashes for 5 seconds and then goes out. Enter the next cycle.
2. Pedestrian traffic light control
2. 1 Control at the same time with the traffic light system. When the north-south traffic red light continues to light up, the east-west pedestrian green light starts, the north-south pedestrian light lights up for 60 seconds, and the east-west pedestrian red light lights up for 30 seconds. Enter the next cycle.
2.2 At the same time when the east-west pedestrian red light is on, the north-south pedestrian green light is on for 25 seconds, then flashes for 5 seconds and then goes out to remind pedestrians to cross the road quickly and enter the next cycle.
2.3 The red light for north-south pedestrians lights up, while the green light for east-west pedestrians lights up for 25 seconds, then flashes for 5 seconds and then goes out to remind people to cross the road quickly and enter the next cycle.
3. Electronic police records violate the control of red light system.
3. 1 When the traffic lights in the north-south direction are on, the buzzer will ring if a vehicle illegally runs the red light (simulated by a switch or grating in the north-south direction); When the light is green, the switch does not work.
3.2 When the east-west traffic light is red, if a vehicle illegally runs the red light (simulated by switch or grating in the north-south direction), the buzzer will ring; When the light is green, the switch does not work.
Directory summary 2
Abstract 3
Chapter 1 Introduction 5
1. 1 the function and research significance of traffic lights 5
Development status of 1.2 PLC: 5
Characteristics and application of 1.3 programmable controller 8
1.4 Overview 9
Chapter II System Scheme Design 1 1
2. 1 Task requirement: 1 1
2.2 control scheme 12
2.3 PLC selection 13
2.3. 1 extension module selection 13
2.3.2, PLC network design 13
2.3.3, software preparation 13
2.3.4 confirm the selected PLC 13.
2.4 programming 13
2.4. 1 Flowchart (see the figure below) 13
2.4.2 timing diagram 14
Program 15
2.5 Experimental Simulation 22
2.6 Original Listing 24
Design summary 25
Acknowledgement 27
Reference 28
Appendix: Complete Statement Table 29 The above answers come from:/html/41/662.htm.