introduction:

With the vigorous development of transportation and the development of intelligent buildings such as buildings and communities, the traditional manually managed parking lot can no longer meet the needs of users and managers for the safety, efficiency, performance and management of the parking lot. Therefore, the intelligent parking lot system should be put into operation. The intelligent management of distributed system is to use highly automated electromechanical equipment, computer network and communication technology team parking lot for safe and efficient management. Due to the reduction of manual participation, personnel costs and losses caused by errors are minimized, and the safety and use efficiency of the whole parking lot are greatly improved.

The design of distributed intelligent parking lot system is based on the guiding ideology of safety, reliability, practicality, openness, scalability and efficiency and distributed structure.1. Hardware design of distributed intelligent parking systemAccording to the needs of decentralized control and centralized management of distributed intelligent parking lot system, Ethernet LAN is introduced for data information sharing, supervision and management. The system is divided into management center station, process management station and field control level, so as to give full play to the advantages of distributed system.

1.1 structure layout of distributed intelligent parking lot systemThe schematic diagram of system structure layout is shown in Figure 1. As can be seen from Figure 1, the system is mainly composed of computer, spass host, automatic identification device, IC card issuing machine, car stopper, monitoring camera, controllable prompt board, etc.Figure 1 structural layout of distributed intelligent parking lot system

1.2 main functions and features of the systemUsing the characteristics of distributed system, centralized management and hierarchical control are realized for the intelligent parking lot. Network management is implemented for the parking lot with multiple exits and multiple entrances. Through screen command and dispatching, the parking lot vacancy information is displayed, which reduces the work intensity and improves the efficiency; The open structure is convenient for system upgrading and capacity expansion.Manual and automatic working modes improve the reliability of the system; The system mainly works in the network mode. In case of network failure, the on-site management computer and local mode work. If the on-site management computer also fails, the spass host and system will cooperate with the manual mode to realize the work of the parking lot.

At the entrance, when the incoming vehicle is detected by the ground induction coil, the camera is excited to capture the image of the vehicle and store the relevant data in the database; At the exit, when the exit vehicle is detected by the ground induction coil, the vehicle image is taken; Realize the linkage of vehicle image, license plate and IC card, which not only enhances the anti-theft function, but also facilitates the management of information.1.3 system working principleThe control center of the system is the central control computer, which is responsible for the coordination and management of the whole system. Including software and hardware parameter control, system general networking management, communication and analysis, command release, etc., integrating management, security, statistics and business statements. It can work independently to form a parking lot management system, or it can be connected with other systems and integrated into a larger network system.

The computer of the process management station completes the management and supervision of video images, IC card issuer and spass host.

The working relationship of relevant equipment can be clearly understood through the car admission flow chart (as shown in Figure 2). The card reader is a remote sensing mode, and the smart card is a non-contact inductive IC card; For the health of video image data, capture the appearance, color, license plate number of the vehicle and the foreign trade of the driver when reading the card at the entrance, and archive it as the card data. Capture the appearance, color and license plate number of the vehicle when reading the card at the exit, compare and archive the image data at the entrance, so as to ensure the consistency of the vehicles with the card number and the safety of vehicle storage.

Fig. 2 flow chart of car admission2. System software design2.1 system function planning

According to the requirements of distributed intelligent parking lot system and users, the functional modules are planned to design and develop the software corresponding to each module. The system has the following main functional modules:System management: (1) system data item setting, relevant equipment working parameters and charging standards; (2) User management: users are authorized at different levels according to their permissions to realize the management of adding, deleting and changing passwords; (3) The system can manage payroll personnel, record staff attendance, and count everyone's charges.Card library management: IC card is a very important auxiliary equipment to realize the function of intelligent parking lot. It should complete the functions of user card production, repair, recharge, validity setting, cancellation, retrieval and printing.

Entrance and exit management: according to the work flow of the distributed intelligent parking lot, realize the automatic collection and control of information in all links of entrance and exit, and simulate the vehicle entry and exit process and its pictures in the way of upwelling animation on the display.Data management: the system software automatically stores the situation of vehicles entering and leaving the parking lot every day in the vehicle management daily account database, and uses various data entry, modification, query, statistics, printing reports, etc.2.2 core technology of software development

(1) Computer C / S (C / b) working mode in LAN. According to the requirements of the parking lot distributed system and relevant departments of users, in order to realize the effective health and management role, plan the functions and working interfaces of management workstations at all levels and on-site control and the flow of data information, and use VB6 or VC6 to develop applications and TCP / IP communication protocols that meet the needs.(2) Configuration of process management computer. Using the configuration software, according to the actual requirements of the distributed monitoring system of the branch parking lot, this paper investigates and analyzes the system, and grasps the structural framework, process, functions to be realized and how to realize these functions of the system as a whole. The configuration work shall be carried out according to the following process: making work screen - defining data object - Animation link - equipment link - writing control process - alarm display - report output - Statistical display.Conclusion: the application of distributed intelligent parking lot system provides accurate, timely, intuitive and funny control and management for managers, field operators and drivers. After the early development, design and testing, the system has preliminarily met the requirements of various timely indicators in the early stage of design.