In recent years, with the rapid development of the Internet, the development of Internet of Things technology has also shown a rapid trend. Under this situation, the major developed countries in the world are vigorously supporting the construction of "smart cities". Of course, China, as the largest developing country, should also accelerate its pace and strive to be at the forefront of creating "smart cities". With the stable and rapid development of China's economy and society, the level and speed of urbanization have been greatly improved. The increase of commercial areas has also increased the number of large outdoor advertisements. When facing bad weather such as strong winds, citizens have to be more careful when walking under these "Big Mac". Therefore, in order to improve the city's safety management level and facilitate the supervision unit to quickly grasp the emergency situation, this paper proposes an intelligent supervision method that uses sensor technology to monitor the tilt of large outdoor advertising, and designs and develops a monitoring system based on the tilt sensor to achieve large-scale outdoor Real-time dynamic monitoring of advertising inclination, and a set of effective early warning level standards have been developed to push early warning messages to managers in real time. The large-scale outdoor advertising monitoring system consists of a front-end information collection and transmission device and a back-end information processing and display part. Among them, the MEMS tilt sensor in the front-end information collection device is used to collect the tilt data of large outdoor advertisements at regular intervals, and the monitoring data is transmitted to the server through GPRS wireless communication, and finally the server completes data analysis, data storage, and monitoring And early warning and Web interface display, when the tilt angle reaches the early warning level, the system will actively send early warning notification SMS for customized users. This system has the characteristics of all-weather and real-time, which improves the efficiency of large-scale outdoor advertising supervision and greatly saves labor costs. It is a beneficial attempt to apply the Internet of Things technology to the field of "smart cities". The thesis focuses on the design and implementation of large-scale outdoor advertising monitoring system, as well as the core issues of early warning level formulation method and danger level prediction method. Among them, the design part of the large-scale outdoor advertising monitoring system includes system architecture, function, database and software and hardware integrated design, and the implementation part includes field construction and software implementation. Since China has not released relevant standards for the monitoring and warning level of the tilt of large outdoor advertising sensors, the formulation of its early warning level standard was carried out based on the relevant specifications of outdoor advertising design and the principle of structural mechanics in this paper, which is also an important innovation in this article And based on the SPSS software, the early warning analysis of the inclination monitoring data was carried out, and the method of timely warning was put forward. The manhole cover is a public infrastructure in the underground pipeline system, which is mainly used to cover various deep well pits on the ground, such as waterways, running water, gas or communication pipelines, to prevent pedestrians and vehicles from falling or falling into them, and avoid accidents. Occurred, at the same time, it can also play a role in isolating and protecting the underground facilities, so the horizontal placement of the manhole cover plays a particularly important role in isolation. Due to the influence of passing pedestrians and vehicles, the manhole cover will gradually deviate from its original position over time, loosening, tilting, and shifting. In the end, it poses a threat to road safety.

         With the continuous expansion of the city's scale, the matching and coverage of public infrastructure construction have increased year by year, and the monitoring and management using traditional inspection schemes have been unable to carry out timely and effective supervision. 

        For this purpose, the manhole cover sensor developed by Shanghai Zhichuan Electronics, whose model is ZCT330E-SWP-N-YK, has a small size, lightweight, +5 V (DC) power supply, TTL output; the product has a magnet inside, cooperates Spiral cable, easy to install; all industrial devices are stable and reliable; impact resistance, vibration resistance; protection grade IP67.

        It can effectively solve the problem of anti-theft of manhole covers. From the perspective of installation, connection, protection, monitoring sensitivity and effectiveness, it can greatly reduce the program and post-maintenance costs. The confirmation of the opposite address can effectively monitor the state of each manhole cover in the monitoring area, reduce the workload of manual inspection, improve the reliability of monitoring and the timeliness of later maintenance.

        Shanghai Zhichuan Electronics is committed to the R & D, production, sales and application of smart city tilt sensors, providing customers with standard and customized solutions to create ideal investment cost performance for customers in the industry.