Editor's Note: Sensors, as the "nerve endings of the information age," have permeated every critical field of the socio-economic landscape. Since October 2025, China Electronics News has invited Guo Yuansheng, Deputy Director of the Science and Technology Committee of the Jiusan Society Central Committee and Executive Vice Chairman of the China Sensor and IoT Industry Alliance, to launch the column "Guo Yuansheng Explains Sensors." The column focuses on eight major fields and scenarios: power, major equipment, intelligent manufacturing, smart agriculture, smart healthcare and big health, smart home appliances and consumer electronics, urban security, and low-altitude economy. Articles such as "Sensors 'Garrisoned' on the Power Generation Side: The Cornerstone of Stable Operation in New Power Systems" and "Sensors for Energy Storage Clarify Three Core Development Directions" have been published successively, receiving widespread attention and high praise from readers. The article published this time focuses on smart sensors in the municipal facilities sector, elaborating on their application prospects, industrial status, and future recommendations to build industrial consensus and promote industrial development.
As the construction of Digital China advances in depth and new-type urbanization steps into a strategic period of high-quality development, cities, as the core carriers of population aggregation and economic activities, have seen their modernization level of governance become a key yardstick for measuring regional development quality. The traditional municipal facility system has long faced pain points such as "broad perception blind spots, long response chains, and fragmented management." From the delayed handling of pipeline leaks to the passive response to traffic congestion, from the difficulty in predicting safety hazards to the lack of precision in public services, these shortcomings not only constrain urban operation efficiency but also affect the improvement of people's livelihood and well-being.
As the "nerve endings" and "data origins" of smart municipal construction, the ubiquitous penetration and deep application of sensor technology are not only the key approach to solving traditional governance problems but also the core support for building a modern urban governance system of "omni-perception, intelligent judgment, and collaborative disposal." From the basic guarantee of water, electricity, gas, and heating to the smart travel of public transportation, and then to the risk prevention and control of safety and emergency response, the omni-perception network constructed by sensors can not only bridge the "last mile" of urban governance but also lay a solid data foundation for smart city construction.
Based on the application requirements of all scenarios, sorting out the adaptation logic and landing path of sensor technology, and looking forward to the direction of technology evolution, can provide clear practical guidance for the intelligent upgrade of municipal facilities, making cities smarter, safer, and more livable.
I. Basic Guarantee Facilities: Building the Perception Layer for Water, Electricity, Gas, Heating, and Public Services
Intelligent Water Affairs System
The water affairs system is the "lifeline" of a city. Relying on manual inspection, it suffers from problems such as difficulty in locating leakage, slow warning of waterlogging, and lagging water quality monitoring. The application of sensor technology can realize dynamic monitoring of the whole process from water source to drainage, improving water affairs operation and maintenance efficiency and emergency response capability.
1. Tap Water Supply: In response to residents' water safety and pipeline leakage issues, water quality sensors and flow sensors need to be deployed. Water quality sensors adopt the electrochemical principle to monitor core indicators such as tap water turbidity (≤1NTU), residual chlorine (0.3-0.5mg/L), and pH value (6.5-8.5) in real time. When the indicators exceed the national standards, the dosing system of the water plant is automatically triggered to adjust or an alarm is sent to the user end; electromagnetic flow sensors are installed at key nodes of the pipeline network. By monitoring the change of water flow velocity in the pipeline, the leakage area is located (location accuracy ±0.5m). Combined with the GIS map, the leakage points are visualized, solving the problems of low efficiency and poor accuracy of the traditional "listening leak" method.
Future Trends: Introduce spectral water quality sensors. Through UV-Vis absorption spectroscopy technology, realize synchronous monitoring of multiple parameters such as turbidity, residual chlorine, and COD (detection time ≤30 seconds), replacing traditional single-indicator sensors; combine AI algorithms to analyze historical water quality data, predict the risk of water quality degradation caused by pipeline aging, and trigger pipeline maintenance in advance.
2. Sewage Treatment and Reclaimed Water Reuse: To ensure the standard discharge of sewage and the efficiency of reclaimed water utilization, ultrasonic level sensors and COD/BOD sensors need to be deployed in sewage treatment plants. The ultrasonic level sensor measures the water level of the pool by emitting high-frequency sound waves (measurement range 0-10m, accuracy ±0.1%FS), and links with the inlet water pump to realize automatic flow regulation, avoiding pool overflow; the COD/BOD sensor is based on the bioelectrochemical principle, monitoring the concentration of organic matter in sewage in real time (COD measurement range 0-5000mg/L, BOD measurement range 0-3000mg/L). When the concentration is abnormal, adjust the air volume of the aeration system and the operating frequency of the aerator to optimize the biochemical treatment efficiency.
Future Trends: Apply biosensors. Through the respiration of immobilized microorganisms or changes in metabolic current, the content of biodegradable organic matter in sewage is fed back in real time, reducing the detection time by more than 50% compared to the chemical method; combined with membrane bioreactor (MBR) technology, deploy conductivity sensors (measurement range 0-2000μS/cm) and turbidity sensors in the reclaimed water reuse link to ensure that the reclaimed water quality meets the reuse standards for greening, toilet flushing, etc.
3. Urban Drainage and Waterlogging Prevention: In response to the problem of rainstorm waterlogging, water level, rainfall, and manhole cover status sensors need to be deployed in rivers, sewers, manhole covers, and other locations. Submersible level sensors are installed at river cross-sections and the ends of sewers to monitor water level changes in real time (measurement range 0-5m, accuracy ±0.5%FS). When the water level reaches the warning threshold (e.g., the river water level exceeds the warning water level by 0.5m), the urban waterlogging warning platform is triggered, and warning information is pushed to municipal departments and surrounding residents; tipping bucket rainfall sensors measure rainfall through the number of tipping bucket flips (measurement range 0-4mm/min, resolution 0.1mm). Combined with meteorological forecast data, the intensity and duration of rainstorms are predicted, and drainage pump stations are started in advance; manhole cover displacement/inclination sensors adopt MEMS technology. When the manhole cover tilts (inclination angle >15°) or displaces (displacement >5cm), an alarm signal is sent immediately to prevent pedestrians from falling. At the same time, the water level under the manhole cover is monitored. When the water level rises to the bottom of the manhole cover (pressure ≥5kPa), it warns of sewer blockage and assists municipal personnel in timely dredging.
Future Trends: Manhole covers integrate pressure transmitters and LoRa communication modules to realize synchronous monitoring of underground water levels and manhole cover status. When the water level rises to a critical value, nearby drainage pumps are automatically triggered to start, reducing the formation time of waterlogging; radar level sensors are deployed at waterlogging-prone points. Compared with traditional submersible sensors, they can avoid the influence of siltation, adapt to harsh water quality environments, and improve monitoring stability.
Intelligent Power and Energy Systems
Energy systems such as power, heating, and gas are the "power sources" of urban operation. Traditional energy management has problems such as uneven load distribution, difficult discovery of leakage hazards, and inaccurate heating temperatures. Sensor technology can realize whole-chain monitoring of energy transmission, distribution, and use, improving energy utilization efficiency and supply security.
1. Urban Distribution Network: In response to grid fluctuations and line overheating after the integration of new energy, current and temperature sensors need to be deployed. Rogowski coil current sensors, adopting the electromagnetic induction principle, measure the distribution network current in a non-contact manner (measurement range 0-6000A, accuracy ±0.2%FS), monitoring line load changes in real time. When the load exceeds 80% of the rated capacity, the dispatch system is triggered to adjust the power supply line to avoid overload tripping; optical fiber temperature sensors are laid along the cable. By monitoring the change of optical fiber light intensity, the temperature of cable joints is monitored (measurement range -50-200℃, accuracy ±1℃). When the temperature exceeds 85℃, an alarm is issued to prompt joint looseness or insulation aging, preventing line short circuits from causing fires.
Future Trends: Adopt flexible current sensing elements made of printed electronics technology, which can be bent to adapt to the bidirectional power flow monitoring of the grid after the integration of distributed photovoltaics and wind power (measurement frequency 10kHz). Compared with traditional Rogowski coils, they are easier to install and can be directly wound on the cable surface; combined with edge computing gateways, load data preprocessing is realized at the sensor end, reducing cloud transmission pressure and improving grid dispatch response speed (from minute-level to second-level).
2. Municipal Centralized Heating: In response to the problems of large heat loss in heating pipelines and uneven indoor temperatures of residents, temperature and pressure sensors need to be deployed. PT100 temperature sensors are installed on the main heating pipeline and branch pipelines to monitor the water supply temperature (45-60℃) and return water temperature (30-45℃) in real time. When the temperature difference between supply and return water exceeds 10℃, the frequency of the circulation pump at the heating station is adjusted to balance the pipeline network flow; diffusion silicon pressure sensors are installed at the beginning and end of the pipeline to monitor the pipeline network pressure (0.2-1.6MPa). When the terminal pressure is lower than 0.2MPa, the makeup water pump is started to supplement the pressure, avoiding insufficient heating for end users; NTC room temperature sensors are deployed in residents' homes to measure indoor temperature (18-24℃). The data is uploaded to the heating company's platform via ZigBee wireless communication to realize "heating on demand." When the indoor temperature is lower than 18℃, the heating flow in the area is automatically increased.
Future Trends: Room temperature sensors integrate human body infrared sensing modules. When no one is detected indoors for more than 2 consecutive hours, the room temperature is automatically lowered to 16℃ to reduce heating energy consumption; distributed optical fiber temperature sensors (DTS) are deployed inside the insulation layer of heating pipelines to realize temperature monitoring of the full length of the pipeline (up to 10km), locating areas with serious heat loss (temperature difference >5℃), assisting in the repair of pipeline insulation layers, and reducing heat energy waste.
3. Gas Transmission: In response to the risks of gas leakage and gas metering issues, gas leakage and flow sensors need to be deployed. Catalytic combustion gas leakage sensors are installed in residential kitchens and industrial/commercial gas consumption places. When the methane concentration in the air reaches 0.5% VOL (10% of the lower explosion limit), audible and visual alarms are triggered, and the gas solenoid valve is linked to close, avoiding gas explosions; ultrasonic flow sensors are used for gas metering. By measuring the time difference of sound wave propagation in the downstream and upstream directions in the gas, the gas flow is calculated (measurement range 0-100m³/h, accuracy ±1.0%FS). Compared with diaphragm gas meters, it can reduce the metering error caused by changes in gas temperature and pressure.
Future Trends: Deploy laser methane telemetry sensors along the urban gas pipeline network. By emitting a laser with a wavelength of 1653nm, the absorption spectrum of methane in the air is detected to realize long-distance leakage detection at the kilometer level (up to 3km) (detection limit 1ppm·m). Combined with drone inspection, it covers areas difficult to reach manually, such as mountains and rivers; residential gas leakage sensors integrate NB-IoT communication modules. When leakage is detected, alarm information is sent to the user's mobile phone, property management platform, and gas company platform simultaneously, shortening the emergency disposal time (from more than 30 minutes traditionally to within 5 minutes).
Intelligent Public Service Facilities
Relying on sensor technology to open up various service perception links, realize efficient resource allocation and precise service supply, and improve the convenience and happiness of the masses.
1. Smart Lighting and Communication: In response to the problems of high energy consumption and single function of traditional street lights, smart street lights integrating multiple sensors need to be deployed. Smart street lights are equipped with illuminance sensors (measurement range 0-100000lux), which automatically adjust the light brightness according to the ambient brightness (e.g., the brightness gradually changes from 30% to 100% at dusk), reducing energy consumption by more than 30% compared to traditional street lights; PM2.5 sensors (measurement range 0-1000μg/m³) and noise sensors (measurement range 30-130dB) are integrated to monitor the urban micro-environment quality in real time. When the PM2.5 concentration exceeds 75μg/m³ or the noise exceeds 70dB, the data is pushed to the environmental protection department to assist in air pollution and noise pollution control; WiFi modules and LED information screens are equipped to provide free network access and real-time traffic and weather information display for pedestrians.
Future Trends: Smart street lights integrate Beidou short message modules. When communication base stations are interrupted due to extreme weather (such as typhoons and rainstorms), they serve as emergency communication nodes to send disaster warning information to the mobile phones of surrounding residents; ozone sensors (measurement range 0-200μg/m³) are added to realize real-time monitoring of photochemical smog, assisting the environmental protection department in formulating volatile organic compounds (VOCs) emission reduction plans.
2. Livelihood Scenario Services: In response to problems such as strong odors in public toilets, difficulty in food traceability in farmers' markets, and unreasonable irrigation in park green spaces, dedicated sensors need to be deployed. Infrared opposing beam stall sensors (detection accuracy ≥99%) are installed in public toilets. The stall occupancy status is judged by blocking the infrared beam, and the data is synchronized to the electronic screen at the entrance of the toilet, facilitating pedestrians to quickly find empty stalls; VOC odor sensors (capable of detecting gases such as ammonia and hydrogen sulfide, detection limit ≤0.1ppm) are equipped. When the odor concentration exceeds the set threshold (e.g., ammonia ≥0.5ppm), the exhaust system is automatically started, and a cleaning reminder is pushed to the cleaner's mobile phone. Smart traceability scales (integrating RFID chips and weighing sensors, weighing accuracy ±0.1g) are deployed in farmers' markets. After merchants enter information such as product origin and supplier, a traceability QR code is generated. Consumers can scan the code to view the whole-process information of food from origin to stall; temperature and humidity sensors (temperature measurement range -20-60℃, humidity measurement range 0-100%RH) are installed in cold chain stalls to monitor the temperature in the freezer in real time (e.g., fresh food freezers need to maintain 0-4℃). When the temperature exceeds the range, an alarm prompts merchants to adjust the freezer settings to ensure food freshness. Soil moisture sensors (measurement range 0-100%vol) and weather station sensors (capable of measuring rainfall, wind speed, and illuminance) are installed in park green spaces. When the soil moisture is lower than 30%vol and there is no rainfall in the next 24 hours, the sprinkler irrigation system is automatically started; when the wind speed exceeds level 3, the sprinkler irrigation is suspended to avoid water waste.
Future Trends: The odor sensor in public toilets is upgraded to a multi-gas detection module, which can distinguish ammonia (toilet odor), formaldehyde (decoration pollution), and carbon monoxide (gas leakage), realizing one device for multiple uses; smart traceability scales support blockchain evidence storage, uploading food traceability data to the blockchain platform to prevent merchants from tampering with information and improving consumers' trust in food safety; park soil moisture sensors integrate salinity sensors (measurement range 0-20ms/cm) to optimize irrigation strategies for parks in saline-alkali land and avoid aggravating soil salinization.
3. Small Public Facilities: In response to problems such as easy loss of smart manhole covers, untimely replenishment of vending machines, and safety hazards of express delivery cabinets, status monitoring sensors need to be deployed. Displacement sensors (measurement range ±50mm) and inclination sensors (measurement range ±90°) are installed on smart manhole covers. When the manhole cover displaces by more than 5cm or tilts by more than 15°, an alarm message is immediately sent to the municipal platform via the NB-IoT network, and the LED light on the surface of the manhole cover flashes to warn and prevent pedestrians from falling; some manhole covers integrate underground water level sensors (measurement range 0-3m). When the groundwater level rises to the bottom of the manhole cover, it warns of sewer blockage and assists municipal personnel in timely dredging. Infrared cargo detection sensors (detection distance 0-50cm) are installed on vending machines/express delivery cabinets to monitor the remaining quantity of goods in the cargo lane in real time. When the remaining quantity of a certain type of goods is less than 3, a replenishment reminder is pushed to the operator's mobile phone; temperature and humidity sensors (temperature measurement range -10-50℃, humidity measurement range 20-90%RH) are equipped on express delivery cabinets to provide environmental temperature and humidity monitoring for special items such as fresh food and medicine. When the temperature exceeds 25℃ or the humidity exceeds 80%RH, the recipient is reminded to pick up the package as soon as possible.
Future Trends: Smart manhole covers integrate pressure sensors (measurement range 0-100kN), which can monitor the weight of passing vehicles. When a vehicle is overloaded (exceeding 50kN), information is pushed to the traffic management department to assist in governing the damage to roads caused by overloaded vehicles; express delivery cabinets add human presence detection sensors (based on millimeter-wave radar technology). Before the cabinet door is closed, it detects whether there is a living body in the cabinet (e.g., a child mistakenly drilling in). If a living body is detected, it refuses to close the door and issues an audible and visual alarm to avoid safety accidents.
II. Public Transportation Facilities: Intelligent Perception of Travel and Logistics
Intelligent Public Transportation Carriers
In response to the problems of inaccurate passenger flow dispatch for buses and subways and slow response to elevator and escalator failures, multiple types of sensors are deployed to realize status monitoring, passenger flow analysis, and fault warning of public transportation carriers, improving travel efficiency and safety.
1. Buses and Subways: Passenger flow statistics sensors adopt binocular vision + AI algorithms. By recognizing the head outline and shoulder features of passengers, the number of people getting on and off is accurately counted (recognition accuracy ≥95%, supporting backlight and occlusion scenarios), and the data is uploaded to the intelligent dispatch platform in real time. When the passenger flow load of a bus route exceeds 80% for 3 consecutive trips, the platform automatically triggers a dispatch command for interval buses, shortening passengers' waiting time (reducing by an average of 10-15 minutes); CO₂ sensors (measurement range 0-5000ppm) and temperature and humidity sensors (temperature 0-40℃, humidity 20%-90%RH) are installed in subway carriages. When the CO₂ concentration exceeds 1500ppm or the temperature exceeds 28℃, the carriage ventilation system is linked to increase the air volume to improve the in-car environment. GNSS dual-mode positioning sensors (GPS + Beidou, positioning accuracy ±2m) combined with vehicle OBU equipment realize real-time location tracking of buses and subways. Passengers can check the countdown to the arrival of vehicles through mobile APPs (error ≤1 minute).
Future Trends: Bus passenger flow sensors are upgraded to 3D structured light sensors, which can not only count the number of people but also recognize large luggage, baby strollers, etc., carried by passengers. The dispatch system can prioritize the arrangement of vehicles equipped with luggage racks or barrier-free facilities based on the recognition results; pressure distribution sensors are installed on subway doors. When human body occlusion is detected during door closing (pressure ≥5N/cm²), the secondary opening of the door is automatically triggered to avoid pinching injuries to passengers.
2. Elevators and Escalators: Elevators are equipped with strain-type weighing sensors (measurement range 0-2000kg, accuracy ±1%FS). When the load exceeds 110% of the rated weight, an overload alarm is triggered and door closing is prohibited, and an overload record is sent to the property management platform; displacement sensors adopt the photoelectric pulse principle. By detecting the relative displacement between the elevator car and the guide rail, accurate floor positioning is realized (accuracy ±1cm), avoiding floor display errors. Escalators are equipped with comb plate foreign object detection sensors (infrared opposing beam type, detection distance 5-10mm). When clothing, shoelaces, etc., are caught in the comb plate, the escalator operation is immediately stopped and an alarm is issued; vibration sensors (measurement range 0-20g, frequency 1-1000Hz) monitor the vibration status of the escalator drive chain and steps in real time. When the vibration acceleration exceeds 5g or the frequency shows abnormal fluctuations, faults such as bearing wear and chain looseness are warned, reminding maintenance personnel to overhaul in advance (fault prediction accuracy ≥85%).
Future Trends: Elevators integrate AI visual sensors. Through cameras in the car, abnormal passenger behaviors (such as running, leaning against the elevator door, and staying for a long time) are recognized, and voice reminders are issued in real time (e.g., "Please do not lean against the elevator door to avoid danger"); escalator vibration sensors are combined with edge computing modules to complete vibration data preprocessing locally, uploading only abnormal data, reducing cloud transmission pressure, and extending the sensor battery life (from 2 years to more than 5 years).
Intelligent Static Traffic and Logistics
In response to problems such as difficulty in finding parking spaces, untimely garbage collection, and low express delivery efficiency, sensor technology is used to realize the efficient utilization of static traffic resources and precise control of logistics links.
1. Public Parking Lots: Geomagnetic sensors adopt the magnetoresistive effect principle and are installed under the parking space ground (burial depth 5-10cm). By detecting changes in the Earth's magnetic field, it is judged whether a vehicle is parked (detection accuracy ≥98%, response time ≤2 seconds). The data is uploaded to the parking lot management platform via the LoRa network. The platform synchronously updates the parking space status to the electronic screen at the entrance and the mobile parking APP, guiding car owners to quickly find empty parking spaces (saving an average of 8-12 minutes in finding a space). Ultrasonic vehicle detectors are installed at the entrance/exit of the parking lot. By emitting 40kHz ultrasonic waves, the vehicle height is measured (measurement range 0.5-3m), automatically distinguishing car models such as sedans, SUVs, and trucks, assisting the management platform in classified charging by vehicle model.
Future Trends: Geomagnetic sensors are upgraded to "geomagnetic + millimeter-wave radar" dual-mode sensors. Even if there is less metal at the bottom of the vehicle (such as new energy vehicles) or the parking space surface is covered with fallen leaves and snow, the detection accuracy can still be maintained at more than 99%; reverse car search sensors are deployed in the parking lot. By matching the car owner's mobile phone Bluetooth signal with the Bluetooth beacon above the parking space (positioning accuracy ±3m), a walking car search navigation route is provided for the car owner.
2. Sanitation and Logistics Vehicles: Garbage trucks are equipped with infrared fullness sensors (detection distance 0.1-1m) and load sensors (measurement range 0-10t, accuracy ±0.5%FS). When the garbage height in the garbage bin exceeds the sensor installation position (15cm from the bin opening) or the total load of the garbage truck exceeds 8t, a fullness/overload alarm is sent to the sanitation dispatch platform. The platform plans the optimal collection route based on the alarm information (reducing the empty driving rate by more than 30%). Express delivery vehicles are equipped with laser obstacle avoidance sensors (measurement range 0-10m, angle 120°) and battery SOC sensors (measurement range 0-100%, accuracy ±2%). The laser obstacle avoidance sensor detects pedestrians, vehicles, and obstacles in front in real time, and automatically decelerates or stops when the distance is less than 1m; the battery SOC sensor uploads the remaining power to the delivery platform in real time. When the power is lower than 20%, the rider is reminded to go to a nearby battery swap cabinet to replace the battery, avoiding power failure midway.
Future Trends: The fullness sensor of the garbage truck integrates an odor sensor (capable of detecting ammonia and hydrogen sulfide). It can not only judge whether the garbage is full but also detect the degree of garbage rot, prioritizing the collection of kitchen waste that is easy to produce odors; express delivery vehicles are equipped with UWB ultra-wideband positioning sensors (positioning accuracy ±10cm), realizing centimeter-level positioning in complex environments such as residential compounds and office buildings, assisting riders in accurately finding the recipient's address.
Intelligent Shared Travel Tools
In response to problems such as random parking of shared bicycles, difficulty in discovering vehicle failures, and range anxiety for electric vehicles, sensor technology is used to realize status monitoring, standardized management, and safety assurance of shared travel tools.
1. Shared Bicycles: GPS + Beidou dual-mode positioning sensors (positioning accuracy ±3m) and Bluetooth smart locks are installed on the vehicle body. Users unlock the vehicle by triggering a Bluetooth signal through a mobile APP. During the ride, the positioning sensor uploads the vehicle location once every 10 seconds. When the vehicle is parked in a no-parking zone (such as inside a residential compound or on a motor vehicle lane), the smart lock refuses to lock and prompts the user to move it to a designated parking spot (no-parking zone recognition accuracy ≥95%). The inclination sensor (measurement range ±90°) detects whether the vehicle is overturned in real time. When the vehicle overturns at an angle exceeding 45° and lasts for more than 5 minutes, an overturn alarm is sent to the operation and maintenance personnel, reminding them to upright the vehicle in time. The Hall speed sensor calculates the riding mileage by detecting the number of wheel rotations (accuracy ±0.1km) and generates a riding track combined with positioning data for users to view.
Future Trends: Shared bicycles integrate tire pressure sensors (measurement range 0-100psi, accuracy ±1psi). When the tire pressure is lower than 25psi, a prompt of "Insufficient tire pressure, it is recommended to change the vehicle" is pushed to the user APP, and a tire repair reminder is sent to the operation and maintenance personnel; the smart lock adds NFC function, supporting unlocking through mobile phone NFC touch in a network-free environment, improving the convenience of use.
2. Shared Electric Vehicles: In addition to the core sensors equipped with shared bicycles, they are also equipped with battery health sensors (capable of monitoring battery voltage, current, and temperature) and motor controller sensors (measuring motor speed and torque). The battery health sensor monitors the battery temperature in real time (normal range 0-45℃). When the temperature exceeds 50℃, it triggers the start of the battery cooling fan and sends a high-temperature alarm to the platform to avoid battery fires; the motor controller sensor detects the motor speed (range 0-500rpm) and torque (range 0-50N·m). When the motor speed is abnormal (e.g., exceeding 120% of the rated speed) or the torque is too large (e.g., exceeding the rated value when climbing), the output power of the motor is automatically adjusted to protect the motor from damage.
Future Trends: Shared electric vehicles install electronic fence sensors (based on UWB technology, positioning accuracy ±5cm) to realize the "pick up and return at fixed points" function. Users need to park the vehicle within the designated electronic fence to lock and return the vehicle, further standardizing the parking order; the battery health sensor combines AI algorithms to predict the remaining life of the battery (error ≤1 month). When the battery life is less than 3 months, operation and maintenance personnel are reminded to replace the battery in advance to avoid power failure midway during the user's ride.
III. Safety and Emergency Facilities: Intelligent Perception of Risk Warning and Emergency Response
Fire Safety Monitoring
In response to fire hazards in various urban buildings and public places such as shopping malls, office buildings, and parks, multiple types of intelligent fire detection sensor systems are deployed to build an all-scenario fire monitoring network, realizing early fire warning and rapid response, and minimizing fire losses and casualties.
1. Indoor Places of Buildings (such as shopping malls, hotels, office buildings, high-speed (subway) rail stations, and other public buildings; government organs, campuses, residential areas, etc.): Core deployment includes photoelectric smoke alarms, rate-of-rise / fixed-temperature heat detectors, and fire hydrant pressure sensors. Among them, photoelectric smoke alarms use the light scattering principle to capture smoke particles in the early stage of a fire, realizing early fire warning (response time ≤10 seconds); rate-of-rise / fixed-temperature heat detectors have both fixed temperature detection (triggered by set threshold temperature) and differential temperature detection (triggered by a sudden rise in temperature rate), adapting to fire monitoring in high-temperature environments such as kitchens and machine rooms; fire hydrant pressure sensors adopt the diffusion silicon pressure sensing principle to monitor the pressure status of the fire water supply system in real time (measurement range 0-2.5MPa, accuracy ±0.5%FS). When the pressure is lower than 0.8MPa, an alarm is triggered to ensure sufficient fire water supply when a fire occurs.
Future Trends: Smoke alarms integrate CO sensors. Through multi-parameter fusion recognition technology, fire smoke is accurately distinguished from interference sources such as kitchen oil fumes and steam, reducing the false alarm rate in household scenarios by more than 60%; relying on the NB-IoT network to realize cloud aggregation of sensor data, linking with the fire emergency platform to realize accurate matching and pushing of alarm information with building floor plans and evacuation routes.
2. Outdoor Public Areas (such as parks, squares, green spaces, gardens, tourist attractions, etc.): Focus on configuring smart fire extinguishers and fire lane infrared light grid sensors. Smart fire extinguishers integrate pressure sensors and RFID identity recognition modules. The pressure sensor monitors the internal pressure of the fire extinguisher in real time (normal range 1.2-1.5MPa). When the pressure is lower than 1.0MPa, operation and maintenance personnel are reminded to replace it; the RFID module can realize the location traceability and usage record tracking of the fire extinguisher, avoiding loss or failure to replace when expired. The fire lane infrared light grid sensor forms a protective network through multiple groups of infrared opposing beams. When a vehicle or obstacle occupying the fire lane is detected (occlusion time >30 seconds), an audible and visual alarm is immediately triggered and information is pushed to the municipal management platform.
Future Trends: Fire lane monitoring is upgraded to use millimeter-wave radar sensors. With the characteristics of penetrating smoke, rain, snow, and vegetation occlusion, 24-hour blind-spot-free monitoring is realized (detection distance 0-50m, angle 120°); combined with video monitoring linkage, when occupying behavior is monitored, automatic snapshot evidence collection and license plate information recognition are performed to improve law enforcement and disposal efficiency.
Personal Safety and Emergency Evacuation
In response to prominent problems such as crowded crowds in parks, stampede risks in large cultural and sports activities, and unsmooth emergency evacuation in buildings, sensors for passenger flow statistics, emergency disposal, and intelligent policing are deployed to build a "monitoring-warning-response-evacuation" whole-chain safety assurance system, ensuring personnel safety and orderly evacuation.
1. Personnel Gathering Places: Core deployment includes smart cameras and high-altitude observation dome cameras. Smart cameras are equipped with binocular vision and AI algorithms to realize face capture, personnel density statistics (accuracy ≥95%), and abnormal behavior analysis (such as running, pushing, staying, etc.). When the personnel density exceeds 1.5 persons/㎡ or abnormal behavior is detected, regional warning is triggered; high-altitude observation dome cameras adopt 360° panoramic monitoring lenses and infrared night vision functions to realize real-time monitoring of large-scale areas (monitoring radius 0-3km), adapting to safety control in open places such as large squares and sports venues.
Future Trends: Cameras integrate sound event detection sensors. Through voiceprint recognition technology, abnormal sounds such as screaming, glass breaking, and explosions are accurately recognized (recognition accuracy ≥90%), realizing "visual + auditory" dual-mode linkage alarms, solving the warning blind spots of traditional video monitoring in dim light and occlusion scenarios.
2. Emergency Disposal Facilities: Deploy one-key alarm pillars and electronic fences. One-key alarm pillars integrate press-type trigger sensors and voice intercom modules. After users press the alarm button, two-way voice communication with the emergency command center can be established immediately (response time ≤3 seconds). At the same time, a built-in GPS positioning module (positioning accuracy ±5m) accurately pushes alarm location information; electronic fences adopt pulse-type infrared sensors to form an invisible protective boundary. When someone illegally climbs over, a high-voltage pulse warning is triggered (safe voltage, only deterrent and non-lethal) and an alarm is synchronized, adapting to boundary protection in key areas such as schools and hospitals.
Future Trends: One-key alarm pillars integrate heart rate and body temperature sensors. When help-seekers trigger an alarm, their physical status data can be uploaded synchronously (heart rate measurement range 40-200 beats/min, body temperature measurement accuracy ±0.1℃). The emergency command center can predict rescue priorities based on health data, assisting rescue personnel in carrying corresponding medical equipment and improving rescue pertinence.
3. Intelligent Policing System: Build a whole-process intelligent perception system of "alarm-dispatch-on-site disposal-feedback," deploying police intelligent patrol robots, mobile policing terminals, and all-scenario linkage sensors. In the alarm link, link one-key alarm pillars, video monitoring sensors, and sound event detection sensors to realize accurate positioning of alarm signals (positioning accuracy ±3m) and real-time collection of on-site audio and video, synchronously triggering surrounding monitoring equipment for key recording; in the dispatch link, police vehicles are equipped with GNSS dual-mode positioning sensors (GPS + Beidou, positioning accuracy ±2m), 4G/5G communication modules, and road condition perception sensors to push the optimal dispatch route in real time, while automatically retrieving traffic light data around the alarm point to assist green wave passage; in the on-site processing link, mobile policing terminals integrate fingerprint recognition sensors, ID card reading sensors, portable gas detection sensors (capable of detecting flammable and explosive gases such as methane and hydrogen, detection limit ≤1ppm), and high-definition camera sensors to realize rapid verification of personnel identity, on-site material evidence image collection, and real-time uploading of environmental dangerous gas detection information; police intelligent patrol robots are equipped with infrared thermal imaging sensors (measurement range -20-150℃), laser obstacle avoidance sensors (measurement range 0-10m, angle 120°), and audible and visual alarm modules. They can independently patrol in high-risk areas such as substations and hazardous chemical warehouses, detect equipment overheating hazards and gas leaks, and immediately alarm and upload on-site image data when abnormalities are found.
Future Trends: Relying on multi-source sensor data fusion and AI algorithms, build an all-domain intelligent policing governance platform, realizing automatic retrieval of multi-dimensional data such as on-site and surrounding video monitoring, traffic conditions, and key personnel information within 1 second after the alarm, assisting the command center in quickly judging the case; police vehicles and on-site sensors are linked in real time, and the terminal automatically generates disposal plan suggestions; on-site disposal data is stored as evidence through the blockchain to ensure that the law enforcement process is traceable, while linking with other urban governance systems (such as traffic and emergency) to realize cross-domain collaborative disposal, forming an intelligent and closed-loop policing governance model.
Infrastructure Structure Safety and Health Monitoring
In response to public facility safety hazards such as lost manhole covers, fallen street lights, and damaged bridge and tunnel structures, full life-cycle status monitoring sensors are deployed to realize early warning and timely maintenance of facility faults, avoiding accidental injuries to pedestrians and vehicles, and ensuring the safe operation of urban infrastructure.
1. Bridges and Buildings: Deploy vibration acceleration, strain gauges, and inclination sensors. Vibration acceleration sensors (measurement range 0-5g, frequency 1-100Hz) perform modal analysis by monitoring structural vibration data to identify the structural health status of bridges and high-rise buildings; strain gauges (measurement range -2000-2000με, accuracy ±1με) are installed on bridge main girders, building load-bearing walls, and other parts to monitor stress changes in real time, avoiding structural damage caused by overload and aging; inclination sensors (measurement range ±30°, accuracy ±0.1°) are used to monitor the tilt deformation of buildings and bridges, triggering a warning when the tilt angle exceeds the threshold.
Future Trends: Large-span bridges adopt distributed optical fiber sensors. Through optical time-domain reflection technology, continuous strain monitoring of the whole bridge is realized (monitoring distance up to 20km), replacing traditional point sensors, realizing blind-spot-free and high-precision deformation warning, and improving warning accuracy by more than 50%.
2. Roads and Underground Pipeline Networks: Deploy soil pressure sensors and pipeline corrosion sensors. Soil pressure sensors (measurement range 0-500kPa, accuracy ±2%FS) are installed under the road subgrade to predict the risk of road collapse by monitoring soil pressure changes; pipeline corrosion sensors adopt the electrochemical corrosion sensing principle and are installed on the inner walls of gas and water supply pipeline networks to monitor the degree of pipeline corrosion in real time and warn of the risk of pipeline network aging and leakage.
Future Trends: Road sensors integrate underground cavity detection radar. Through the principle of electromagnetic wave reflection, cavities under the road are identified (detection depth 0-5m, cavity resolution ≥0.5m), which can warn of the risk of road collapse 3-6 months in advance; underground pipeline network sensors adopt optical fiber sensing technology to realize long-distance and high-precision leakage and corrosion monitoring, adapting to long-term stable operation in complex underground environments.
3. Small Public Facilities (Manhole Covers, Street Lights): In addition to deploying displacement and inclination sensors, smart manhole covers add anti-fall sensors and pressure sensors. The anti-fall sensor adopts an infrared opposing beam type with a detection distance of 0.5-1m. When the manhole cover is missing, the infrared beam is blocked and an alarm is immediately triggered; pressure sensors (measurement range 0-500kg, accuracy ±1kg) are installed on the edge of the anti-fall net under the manhole cover. If a pedestrian accidentally falls, the sensor detects a weight ≥30kg and immediately sends an emergency rescue signal to the municipal department, while starting the audible and visual alarm in the anti-fall net to remind nearby personnel to participate in the rescue. Inclination sensors (measurement range ±45°, accuracy ±0.2°) are installed on street light poles. When the street light tilts at an angle exceeding 10° due to strong wind, collision, etc., a falling warning is sent to the operation and maintenance personnel; combined with vibration sensors (measurement range 0-10g), it monitors whether the street light pole is hit by a vehicle (vibration acceleration ≥5g). Even if the collision does not cause immediate falling, it can remind subsequent checks on whether the pole structure is damaged.
Future Trends: Small public facility sensors integrate energy harvesting modules (solar + vibration power generation), extending battery life to more than 5 years and reducing operation and maintenance costs; build a small public facility intelligent monitoring network to realize data interoperability and linkage warning, improving the intensive level of urban infrastructure operation and maintenance.
IV. Municipal Sensor Industrial Ecology and Development Strategy Assessment
Market Size and Growth Drivers: Data-Driven Demand Release
1. Overall Market Size: Benefiting from the continuous promotion of new-type urbanization, urban renewal, and special plans for smart municipal construction, the municipal sensor market has entered a period of rapid growth. According to authoritative industry data, the market size of China's municipal sensors reached 38.6 billion yuan in 2025, a year-on-year increase of 18.2%; it is expected that the market size will exceed 65 billion yuan in 2028, and the compound annual growth rate (CAGR) from 2025 to 2028 will remain at a high level of 18.5%. This growth trend far exceeds the average growth rate of the global sensor market (about 12%), which is mainly derived from China's large-scale investment in the intelligent transformation of infrastructure.
2. Segmented Field Structure: From the perspective of market segmentation, the pattern of "traffic-led, safety-leap, and livelihood-filling" is presented. Among them, the market size of public transportation sensors (including parking lots, shared travel, buses, and subways) is 12.7 billion yuan, accounting for 32.9%, which is the largest segmented field. The main driving factors are the intelligent transformation of urban static traffic (more than 120,000 smart parking lots have been transformed nationwide) and the intelligent upgrade of shared travel tools (the intelligent transformation rate of existing shared bicycles exceeds 85%); the market size of safety and emergency sensors (fire protection, structure monitoring, intelligent policing) is 8.9 billion yuan, accounting for 23.1%, with a year-on-year growth rate of 22.5%, becoming the fastest-growing segmented field, benefiting from the policy reinforcement of urban safety resilience construction and the normalization of safety inspections of old facilities; the market size of water affairs sensors (leakage detection, drainage and waterlogging prevention) is 7.6 billion yuan, accounting for 19.7%. Driven by the special action for urban waterlogging control (23,000 waterlogging-prone points have been transformed nationwide), the demand for underground pipeline network monitoring sensors has surged; the market size of public service sensors (smart street lights, livelihood scenarios) is 9.4 billion yuan, accounting for 24.3%. The carrier value of smart street lights as "urban perception neural network nodes" is highlighted. More than 35,000 smart street light projects have been built nationwide, driving the demand for multi-sensor integrated applications.
3. Core Growth Drivers: First, at the policy end, the country has issued the "Action Plan for Intelligent Transformation of Urban Infrastructure," clearly requiring that the coverage rate of the perception network of core municipal facilities such as urban water supply, gas, and drainage should exceed 90% by the end of 2027, directly driving the rigid demand for sensors; second, at the technology end, the maturity of low-power wide-area network technologies such as NB-IoT and LoRa has improved (network coverage rate exceeds 95%), providing communication support for the large-scale deployment of sensors; third, at the operation and maintenance end, the operation and maintenance cost of the traditional "sea of people inspection" model accounts for more than 60%, while intelligent monitoring by sensors can reduce operation and maintenance costs by 30%-50%. The demand for cost optimization promotes the accelerated penetration of the market.
Industrial Pattern: The Path of Localization Development under Layered Competition
1. Competition Echelon Division: The current market has formed a clear three-tier competition echelon. The first echelon is international head enterprises, represented by Siemens, Bosch, and Honeywell. Relying on core chip R&D, high-precision sensing technology, and whole industry chain integration capabilities, they dominate the high-end market. Their market share in fields such as laser methane telemetry, distributed optical fiber monitoring, and high-precision infrared thermal imaging exceeds 70%. Their products are mainly used in high-end scenarios such as large bridges and tunnels and national-level new areas, and the unit price is 3-5 times that of domestic products; the second echelon is domestic leading enterprises, represented by Hangzhou Maileke, Hikvision, and Hanwei Technology. Through the integrated solution of "hardware + software + platform," they have achieved breakthroughs in the mid-to-high-end market. Their market share in fields such as smart street light sensors, geomagnetic parking space detectors, and conventional gas leakage sensors exceeds 60%. Among them, Hanwei Technology's market share in the water affairs sensor field reaches 28%, ranking first in China; the third echelon is small and medium-sized enterprises in segmented fields, such as Suzhou Good-Ark (MEMS sensor chips), CSG Smart Grid Sensing Technology (power sensing terminals), and Keli Sensing (weighing sensors). They focus on deep cultivation in a single category, forming technical barriers in segmented scenarios. Although their market share is not high, their profitability stability is strong.
2. Core Links of the Industry Chain: Upstream core components (MEMS chips, laser emission modules, signal conditioning chips) remain a shortcoming for domestic production. The localization rate of high-end MEMS chips is less than 15%, mainly relying on overseas enterprises such as STMicroelectronics and Texas Instruments; the midstream sensor manufacturing link has realized large-scale mass production. Domestic enterprises have cost advantages in the fields of packaging and testing and structural design. The capacity utilization rate of conventional sensors exceeds 80%; the downstream application end presents a model of "government-led + enterprise participation." Procurement in fields such as municipal, traffic, and emergency is mainly dominated by government special bidding. Head enterprises occupy the dominant position with qualification advantages and localization service capabilities. Small and medium-sized enterprises mainly enter the market through cooperation with system integrators.
3. Localization Progress: Comprehensive substitution has been realized in the mid-to-low-end field. The domestic market share of products such as manhole cover sensors, passenger flow statistics sensors, and temperature and humidity sensors exceeds 90%; substitution in the mid-to-high-end field is accelerating. The localization rate of products such as optical fiber temperature sensors and ultrasonic flow sensors has increased to 35%-40%, which have been applied to major projects such as the Hong Kong-Zhuhai-Macao Bridge; there is still a gap in the high-end field. The localization rate of core components such as distributed optical fiber demodulation chips and kilometer-level laser telemetry modules is less than 5%, becoming a key bottleneck restricting industrial upgrading.
Core Challenges: Triple Constraints of Technology, Standards, and Ecology
1. Technology Level: First, there is insufficient breakthrough in high-end sensing technology. Core technical indicators such as noise control of high-precision MEMS chips and stability calibration of laser sensors have a 2-3 generation gap with international advanced levels, leading to the dependence of high-end products on imports; second, there is a bottleneck in low-power technology. For sensors in scenarios without municipal power, such as smart manhole covers and underground pipeline networks, the current battery life is generally 1.5-2 years. Frequent replacement leads to a surge in operation and maintenance costs. The integrated application of low-power chips and energy harvesting technologies (such as vibration power generation and thermoelectric generation) is not yet mature; third, the data fusion capability is weak. The data value of a single sensor is limited, while the development of spatiotemporal calibration and heterogeneous fusion algorithms for multi-source sensor data lags behind, leading to prominent "data island" problems, making it difficult to support collaborative decision-making for smart municipalities.
2. Standards Level: First, there is a lack of unified technical specifications. The communication protocols of sensors from different manufacturers (such as NB-IoT terminal interfaces and data transmission formats) are different, resulting in a data interoperability rate of less than 40% across brands and scenarios, increasing the difficulty of system integration; second, there is a lack of installation and operation and maintenance standards. There are no clear specifications for the installation of sensors in complex scenarios such as old residential areas and underground pipeline networks, leading to uneven construction quality and a sensor failure rate of more than 15%; third, data security standards are imperfect. Municipal sensor data involves sensitive information such as urban infrastructure layout and public safety, but the current security encryption standards for data collection, storage, and transmission are not yet unified, posing risks of data leakage and tampering.
3. Ecology Level: First, the industrial ecology of "sensor + platform + operation and maintenance" has not yet been formed. Most enterprises still focus on hardware sales, lacking the layout of backend data services and operation and maintenance systems, resulting in low industrial added value; second, the R&D capability of small and medium-sized enterprises is insufficient. Industry R&D investment is mainly concentrated in head enterprises (R&D expense ratio exceeds 8%), and the R&D investment proportion of small and medium-sized enterprises is less than 3%, making it difficult to support core technology breakthroughs; third, cross-domain collaboration is insufficient. There is a lack of collaborative R&D mechanisms between sensor enterprises and municipal design units, construction enterprises, and software service providers, leading to a disconnect between product iteration and actual application needs.
Development Strategy: Dual-Wheel Drive of Technology Breakthrough and Ecology Reconstruction
1. Technology Upgrade Direction: First, increase R&D investment in key components such as MEMS chips, laser emission modules, and high-sensitivity detectors. Relying on the National Integrated Circuit Industry Investment Fund, promote collaborative research in the whole chain of "chip design-manufacturing-packaging," with the goal of breaking through 50% in the localization rate of high-end MEMS chips by 2030; second, promote the integration of low power consumption and intelligence. Adopt the architecture of "low-power MCU + edge computing chip" to realize local data preprocessing and abnormal recognition of sensors, reducing cloud transmission pressure. Combined with energy harvesting technologies such as solar and vibration power generation, extend the life of sensors in scenarios without municipal power to more than 5 years; third, build a multi-source data fusion system. Develop AI-based spatiotemporal calibration and data fusion algorithms to realize hierarchical intelligent processing of "sensor-edge node-cloud platform" and improve data decision-making value.
2. Industrial Ecology Construction: First, promote the construction of the standard system. Led by industry associations, join hands with leading enterprises to formulate unified municipal sensor communication protocols, installation and operation and maintenance specifications, and data security standards. Focus on promoting the implementation of the general interface standard for NB-IoT municipal sensors to realize cross-manufacturer data interoperability; second, cultivate the integrated model of "hardware + software + service." Guide enterprises to transform from single hardware suppliers to comprehensive solution service providers, providing whole-process services such as sensor deployment, data platform construction, and long-term operation and maintenance assurance to improve industrial added value; third, build a collaborative innovation ecology. Establish a "enterprise-university-research institute-government" industry-university-research-application cooperation mechanism, focus on typical scenarios such as urban waterlogging monitoring and bridge structure health, carry out joint research, and promote the rapid transformation of technological achievements.
3. Deepening Application of Scenarios: First, upgrade from "passive monitoring" to "active prediction." Based on historical and real-time data of sensors, build an AI prediction model to realize advance prediction of risks such as elevator failures, pipeline network leakage, and road collapse (e.g., elevator failure warning 30 days in advance, pipeline network leakage location 7 days in advance); second, promote cross-domain system linkage. Break the data barriers of sensors in fields such as traffic, water affairs, and safety, build an all-domain smart municipal management platform, and realize whole-chain responses such as "waterlogging warning-traffic control-emergency rescue" and "gas leakage-valve closing-fire linkage"; third, expand the penetration of livelihood scenarios. Deploy low-cost and highly reliable sensors in scenarios such as old residential areas, farmers' markets, and community parks to solve livelihood pain points, while accumulating scenario data to feed back technology iteration.
Conclusion
Although municipal sensors are hidden in the urban texture, they deeply penetrate every scenario of people's clothing, food, housing, and transportation—from pipeline network sensors that ensure water safety to parking space detectors that optimize travel efficiency, from gas leakage alarms that guard home safety to heating sensors that adjust comfortable room temperatures. These "invisible guards" use precise perception as a pen to outline the delicate contours of people's livelihood and well-being, bringing the temperature of urban governance directly to the masses.
More importantly, as the "data cornerstone" and "perception origin" of smart city construction, the current all-domain deployment pattern of municipal sensors is precisely the prototype of smart cities. In the future, with the deep iteration of 5G, AI, and IoT technologies, these scattered perception nodes will break barriers and deeply integrate to build an all-domain covered and all-domain linked urban perception neural network. The massive, real-time, and accurate data they collect will become the "source of living water" for the smart city decision-making hub, supporting the intelligent upgrade of all fields such as urban planning, resource scheduling, emergency response, and public services, and promoting the leap of urban governance from "experience judgment" to "data-driven" and from "passive response" to "active prediction."
From prototype to core support, the iterative upgrade path of municipal sensors is precisely the key path for smart cities to move from concept to reality. Under the dual waves of new-type urbanization and digital transformation, municipal sensors will continue to consolidate the data foundation of smart cities, making cities smarter, safer, and more livable, and injecting lasting smart momentum into the high-quality development of modern cities.
Author | Guo Yuansheng, Deputy Director of the Science and Technology Committee of the Jiusan Society Central Committee, Executive Vice Chairman of the China Sensor and IoT Industry Alliance
Editor | Yang Pengyue Art Editor | Ma Liya Supervisor | Zhao Chen