chrispeng [ad_1]
A background introduction:
With the rapid development of the national economy and the acceleration of urbanization and motorization, the scale of cities has continued to expand, and the number of motor vehicles and road traffic flow has increased sharply. Especially in large cities, the increase in public transport vehicles, the extension of lines, and the increase in the number of vehicles, traffic operation Not smooth. Despite the construction of a large number of transportation facilities, traffic congestion is still very serious. Many years of practical experience at home and abroad have shown that an important way to solve urban traffic problems is to develop public transportation, establish an advanced public transportation system APTS (Advanced Public Traffic System), and improve road capacity and bus operation management. The urban public passenger transport system has not yet introduced (or is in the process of) introducing advanced high and new technology, and basically still adopts the manual dispatching method of “fixed departures and stuck points at both ends”, which causes the speed of public transportation vehicles to drop, and the travel interval is not balanced, which often occurs.” The phenomenon of “crossing of cars” and “large gaps” have seriously affected the service quality of public transport passenger transport. Especially due to the lack of modern communication means, dispatchers cannot understand the conditions of operating vehicles in real time, and it is difficult to take dispatching measures in a timely and effective manner. Bus dispatching is in a backward status of “invisible and inaudible”, with greater blindness and lag. By applying RFID to the bus yard management system, it can realize the automatic, accurate, long-distance, non-stop collection of information for buses entering and leaving the station, so that the bus dispatching system can accurately grasp the real-time dynamic information of the bus entering and leaving the bus parking lot. Through the implementation of this system, the management level of buses can be effectively improved. The collected data can be researched and analyzed by computer, and the rules of vehicle operation can be grasped, the loopholes in vehicle management can be eliminated, the intelligent management of buses can be realized, and the image of the city can be improved. Thereby improving the management level of urban public transportation operation and dispatch.
Two practical significance:
The vehicle scheduling management system is the core component of the intelligent transportation system. It uses advanced information and communication technology to collect dynamic and static road traffic information, and conduct real-time analysis. According to the analysis results, the vehicle’s driving route and travel time are arranged to achieve Make full use of limited traffic resources, improve the efficiency of vehicle use, and at the same time understand the operating conditions of vehicles and strengthen vehicle management. RFID technology, as an effective means of information collection in the traffic dispatch system, will play an important role in the traffic dispatch management system.
Three system design:
(1) Topological structure diagram of the system
Including long-distance reading and writing system, background processing system, LED display system.
(2) The workflow and characteristics of the system
When the bus enters the parking lot, the remote reader reads the electronic tag number placed on the vehicle. The reader automatically transmits the globally unique number or vehicle-related information that it reads to the background computer for processing. Record and process this information, record the time of entry of the vehicle and vehicle-related information, and determine in the background which parking space the vehicle should be parked in, and transmit this information to the LED display. The driver can use the LED display. Know which parking space should be parked and some additional information, such as the next trip time (this time is the result of automatic calculation by the background computer), etc. When the bus leaves the field, the vehicle information is read by the remote reader, and the back-end system records the time and other information of the field and writes the records to the back-end database. The management of the whole process avoids human intervention, minimizes the operating cost of the system and reduces the inevitable losses caused by manual operation.
The functions and characteristics of RFID application in the public transportation management system include the following aspects: automatic recognition of long-distance without stopping, real-time fixed-point collection of bus entry and exit times, and determination of the location of the parking lot where the bus is located; dispatch center and parking lot LED The display board guides the parking space where the bus should stop after entering the station. This system avoids the situation of non-return at night such as the bus parked in other social parking lots. At the same time, it also controls vehicle scheduling, traffic statistics, vehicle attendance, task assessment, and maintenance period. Automated management of reminders, vehicle maintenance records, inspection records, etc.
Four: Standards for equipment selection
The RFID bus intelligent management system adopts a long-distance reader, which requires a reading distance of 6-8 meters, and the reader’s reading speed is above 30km/h, outdoor installation, and moisture-proof design. The label card requires a unique ID number in the world, a writable area of 928bits, and a working temperature designed for industrial use.
The RFID bus intelligent management system long-distance reader provided by Shenzhen Xianshi Technology has a reading distance of 8 meters, a reading speed of 120 km/h or more, and an all-weather outdoor work design. Since the electronic label card of the company has a unique ID number, it has a writable area of 928 bits, and the working temperature can meet the use of different occasions.
In this design, the “Sense series 915MHz long-distance passive radio frequency tag system” produced by Shenzhen First Technology Co., Ltd. is provided. The vehicle electronic label card is an electronic card that weighs less than 10 grams and is the size of a business card. Installed on the windshield of every car. It is an authorization card issued by a bus company department to vehicles in a dedicated lane. Using microwave technology, when the signal of the car electronic identification reader is received by the car electronic identification card, it can automatically respond and send out a microwave signal containing vehicle information. After the reader receives it, it decodes various identification information related to the vehicle to achieve the purpose of automatic identification. Using these read-write devices, it can perform short-range microwave wireless communication with automotive electronic identification cards installed on vehicles that are driving or parked at a distance of 8-10 meters, and collect the information stored in the vehicle identification card through the lane computer. Analysis and non-contact recognition, the recognition time only takes 0.2 to 0.5 seconds. Since the microwave wireless communication between the automobile electronic identification reader and the automobile electronic identification card is completed within a few microseconds, the reading of the license plate information will not be affected when the vehicle is running at a high speed. It can realize the automation of license plate recognition of authorized vehicles and the computerization of recognition results. This system has a friendly software interface, it is very convenient to connect with other systems, and can be easily used for the management of authorized vehicles. Shenzhen Xianshi Technology Co., Ltd. Sense series 915MHz long-distance passive radio frequency tag system has the following characteristics:
-Working frequency range is 902MHZ-928MHZ frequency hopping work
-The response speed is fast, and the card reading time is only 2ms/32bits.
-The reading distance is far, the farthest can reach 2-8M.
-Strong anti-interference ability, system operation is basically not interfered by the external natural environment
-The cost is relatively low, because passive cards are used, and the price is much lower than that of active electronic tags.
-Long service life, because it adopts a passive system and does not require self-contained battery to provide power. Instead, it extracts energy from the reader through electromagnetic coupling, and then transmits its own information to the reader.
Product performance indicators of Sense series readers
(1) Working frequency: ISM 902MHz～928MHz; or user setting, fixed frequency operation.
(2) Working mode: work in the mode of wide-spectrum frequency hopping (FHSS) or fixed-frequency end transmitting pulse, controlled by software;
(3) Card reading sensitivity: the reading range of up to 12 meters can be adjusted by multi-level software control;
(4) Card reading speed: controlled by software, the average reading of a single card is less than 2ms per 32bits
(5) Security mechanism: able to check the legality of electronic tags;
(6) Card reading mode: two kinds of automatic card reading and external trigger control;
(7) Data output interface: (choose one at the factory)
A Wiegand 26/34 port, compatible with the existing domestic IC card application controller.
An RS232 port can carry out two-way data transmission, and the communication protocol is open to users.
An RS485 port can carry out two-way data transmission, and the communication protocol is open to users.
(8) Antenna: a horizontally polarized microwave antenna with +12dBi gain.
(9) LED indicator light: red light-indicating 5V power supply, yellow light-indicating antenna connection, green light-indicating data output communication status;
(10) Power input: +DC12V DC 3A;
(11) It has outdoor rainproof function.
(12) Weight: ABS/metal shell, the whole machine weighs about 4Kg
(13) Working temperature: -25℃~+55℃.
Five application effects and cases
The RFID public transportation vehicle remote identification system launched by Shenzhen Xianshi Technology Co., Ltd. has been successfully applied to multiple depots of Shanghai Public Transport Group and multiple depots of Yunnan Kunming Public Transport. After the application, it provides automation for the intelligent management of dispatching of bus companies. Management provides full automation for the data collection of vehicle entry and exit, and vehicle entry and exit and monitoring play an important role. On the one hand, it has greatly improved the image of establishing a brand-new urban bus management, prevented the loopholes in manual operation, filed data, and ensured the safety and reliability of bus access. It also greatly promoted the pace of urban automation construction and established a foundation for the industry. An example of the successful application of new technologies.
[ad_2]
