With the development of urban economy, the advancement of urbanization, and the changes in the density, intensity and spatial and temporal distribution characteristics of urban transportation demand, advanced intelligent traffic control techniques and methods are used to optimize, comprehensively control and manage urban traffic flow. Become an important issue.
This article refers to the address: http://
The intelligent traffic control system mainly completes the functions of collecting, integrating, processing, analyzing and judging, assisting decision-making, execution and control of traffic information and data, release of traffic information, and evaluation of execution and control effects, static traffic data, dynamic traffic information and The traffic situation is an important input to the system, and the integrity, real-time and accuracy of its acquisition and processing are the key to the system.
The current traffic basic data and information collection generally adopts traffic vehicle detectors, mainly including a loop coil detector, an ultrasonic Doppler detector, an infrared detector, a microwave traffic detector, and a video vehicle detector, etc., through the detection area or The detection of section vehicles carries out the measurement, prediction and calculation of traffic flow, point speed, average speed of road sections, road occupation rate, traffic congestion and accidents, and traffic control system realizes traffic control and coordination at the point, line and surface level. It is reflected in the fine-tuning of traffic signal parameters at intersections, which in turn affects the running time of vehicles on the road; however, for the current situation of mixed traffic in China, these detection methods have problems such as large data error/deviation, long response period, and poor adaptability of use conditions, especially difficult. Meet the parameter requirements for providing traffic control effectiveness assessment.
The vehicle detection system based on wireless positioning technology proposed in this paper will deploy vehicle-mounted mobile positioning device on taxis and buses with high frequency of practical road traffic facilities and can reflect traffic characteristics, and use it as a dynamic traffic parameter to collect vehicles and measure vehicles in real time. Geographical coordinates, calculation of vehicle speed, combined with intelligent traffic geographic information system, provide real-time traffic information, traffic situation and traffic assessment parameters for traffic control.
system design
The vehicle detection system based on wireless positioning technology is mainly composed of a dynamic detection vehicle vehicle equipment, a city traffic command platform, a transportation management center (taxis, public transportation) management platform, and a data communication platform. The vehicle equipment is designed to have positioning. And communication function embedded system terminal equipment. The key technologies of this system mainly include wireless positioning technology, geographic information technology, traffic control technology, wireless communication technology, embedded system and embedded real-time operating system.
Positioning plan selection
At present, the main wireless positioning systems include: the spatial positioning system represented by the European Galileo system, the US GPS system, the Russian GLONASS system, and the China Beidou system; (2) the location-based service provided by the major mobile communication operators covering almost all of China's territory. (LBS)-based network positioning system (3); traffic information navigation and positioning platform based on intelligent development of wireless broadcasting technology, such as the European RDS-TMC (Traffic Message Channel) system.
Considering the practicability, maturity and technological advancement of the system, project investment cost and long-term use cost, it is recommended that the system select the TMC (Traffic Message Channel) positioning scheme and complete the urban intelligent traffic positioning and navigation with the cooperation of the broadcasting system. The establishment of the system. In addition, from the viewpoints of positioning accuracy, response period, and vehicle motion posture, the gyroscope (acceleration sensor) can be used to implement inertial positioning as a supplementary means.
Communication plan selection
The communication between the vehicle equipment and the traffic operation management center and the traffic command center can be through the public mobile communication platform, the dedicated wireless trunking communication platform, or the modification of the existing vehicle communication equipment. It is recommended to use the latter two; the traffic operation management center and the traffic command Dedicated or leased high-speed communication links should be used between the centers.
Vehicle equipment design
The in-vehicle device is mainly composed of a CPU, an RDS module, an acceleration sensor, a display and input unit, a data exchange unit, and a power management unit. The application software mainly completes the functions of decoding, information extraction, vehicle positioning, vehicle motion parameter calculation, traffic information and scheduling information display and output of RDS digital broadcast information.
Traffic command center
In order to realize the function of the TMC (Traffic Message Channel) system, the traffic management department shall coordinate the relevant units to carry out the intelligent upgrade and transformation of the urban FM broadcasting system and establish a platform for the urban intelligent traffic positioning and navigation system.
· Establish urban traffic geographic information system, integrate geometric information, basic attributes, enhanced attributes of spatial elements, and socio-economic information, traffic status information, etc.;
· Establish a data processing platform, complete the data collection of the real-time geographic coordinates of the traffic parameter collection vehicle, the vehicle travel speed, etc., and use the intelligent search and multi-strategy data mining technology to combine the urban traffic geographic information system to realize the real-time traffic information required by the traffic control system. Extraction, analysis, processing, etc. of traffic situation and traffic assessment parameters;
· Establish an integrated access platform to realize the data communication, information exchange and release of the city FM radio system, the transportation management center (taxi, bus) scheduling and communication platform, and the urban traffic control system;
· Establish a comprehensive information display system.
system applications
The main function of the vehicle detection system based on wireless positioning technology is to provide real-time traffic information, traffic situation and traffic assessment parameters for traffic control. At the same time, it can be applied to the following aspects after appropriate expansion design:
Dynamic path induction, based on the need for active guidance, provides traffic travellers or potential traffic travellers with the shortest path or optimal path chain to single or multiple destinations, making vehicle travel more convenient and faster; The user's behavior is reasonably analyzed and predicted, which is conducive to achieving the spatial and temporal distribution of traffic flow and alleviating congestion and environmental pollution;
· Public transportation is preferred. Through the positioning and operation management monitoring of urban public transportation vehicles, priority signals are applied to public transportation vehicles close to intersections to ensure the continuity of driving and improve the traffic capacity of the road network;
· Traffic signal optimization and intelligent control, through real-time traffic control effect evaluation, optimizing signal control parameters, improving traffic control models, improving intelligent channelization functions at traffic intersections and sections, improving utilization of road infrastructure and resources, and reducing traffic congestion ;
· Traffic information release, providing travellers with various traffic information, so that travellers can choose travel time, transportation mode and transportation route so that they can reach the travel destination quickly, conveniently and safely;
The system can also be applied to vehicle dynamic dispatching of traffic operation management, vehicle safety management, stolen vehicle search and positioning, and dynamic recording of vehicle driving conditions.
in conclusion
This paper briefly analyzes the basic parameters of traffic vehicle detection technology and traffic control, introduces the overall design idea of ​​vehicle detection system based on wireless positioning technology, and studies its basic application in the field of intelligent traffic control. I believe that with the dynamic traffic information system Development and promotion, as well as industry research and development in traffic control theory, models, technology and equipment. It can be foreseen that the technology described in this paper has broad application prospects in the field of intelligent traffic control.
48V 100AH Powerwall Solar Battery
Shenzhen Jiesai Electric Co.,Ltd , https://www.gootuenergy.com