In the operation and maintenance system of underwater projects such as bridge piers, subsea oil and gas pipelines, and water conservancy dams, the inspection link has always been the key to ensuring structural safety and avoiding accident risks. Traditional underwater inspection relies on manual operations by divers, which is limited by environmental factors such as water depth, visibility, and current speed. It is not only inefficient but also has extremely high safety hazards. The emergence of underwater inspection cameras, with their unique technical characteristics, has completely changed the operation mode of underwater engineering inspection and become an indispensable core tool in modern underwater engineering operation and maintenance. Its application advantages are mainly reflected in the following four dimensions:

The environment where underwater projects are located is complex and changeable. Shallow waters may face problems such as strong light reflection and turbid water, while deep waters have extreme conditions such as high pressure, low temperature, and complete darkness. These all bring great challenges to traditional inspection. Underwater inspection cameras have perfectly broken through these environmental limitations through targeted technical design: On the one hand, the low-light image sensor and wide dynamic range technology equipped can clearly capture object details in the dark environment of deep waters or under strong light interference in shallow waters. For example, in the inspection of subsea oil and gas pipelines at a depth of 100 meters, even without the assistance of external light sources, corrosion spots of 0.5mm level on the pipeline surface can still be identified; On the other hand, the high-strength waterproof and pressure-resistant shell can withstand the pressure of water depth up to 1000 meters, adapting to inspection scenarios of different depths such as bridge foundations, dam bodies, and deep-sea pipelines. There is no need to adjust the type of inspection equipment due to water depth, which greatly simplifies the operation process. In addition, some underwater inspection cameras can also be combined with remotely operated vehicles (ROVs), and move stably in turbulent currents through remote control, avoiding the problem that manual diving cannot operate accurately due to current impact. This increases the efficiency of a single inspection by 3-5 times. The bridge pier inspection that originally took 3 days can now complete the full-process data collection in only 1 day.

Underwater inspection is a high-risk industry. Divers may encounter risks such as drowning, decompression sickness, and underwater biological attacks during operations. Especially in deep waters or complex current environments, the incidence of safety accidents is extremely high. Through the "unmanned" or "less-manned" operation mode, underwater inspection cameras fundamentally reduce safety risks: inspectors do not need to go into the water, but only need to operate the camera on the surface control platform or remote terminal to complete the all-round shooting and data transmission of underwater structures. Taking the underwater pier inspection of a cross-sea bridge as an example, the traditional method requires 2 professional divers to take turns diving, each operation time does not exceed 30 minutes, and a medical support team must be on standby at any time; while using an underwater inspection camera, only 1 operator is needed to control the equipment on the bridge deck, and continuous operation for 8 hours has no safety risks. This not only avoids the threat to the lives of divers but also reduces additional costs such as medical support. At the same time, for underwater projects with high-risk environments such as toxic water bodies and radioactive pollution (such as industrial wastewater discharge pipeline inspection), underwater inspection cameras can directly go deep into the polluted area for operation without worrying about damage to personnel health, filling the application gap of traditional inspection methods in high-risk environments.

Structural defects of underwater projects (such as cracks, corrosion, and leakage) are often hidden. Traditional manual inspection relies on divers' visual observation and empirical judgment, which is prone to missing subtle defects due to subjective errors or visual blind spots. If these defects are not found in time, they may gradually expand and cause serious accidents. Relying on high-resolution imaging and data storage functions, underwater inspection cameras have achieved a qualitative leap in inspection accuracy: mainstream equipment has a pixel count of more than 20 million, and with a macro lens, it can clearly capture subtle cracks on the concrete surface, texture characteristics of steel corrosion, and even the aging status of sealant at pipeline joints. The inspection accuracy can reach 0.1mm, far exceeding the 1mm limit of manual visual observation. More importantly, the images and videos taken by the camera can be transmitted to the cloud database in real time to form a complete inspection file. Inspectors can zoom in, mark, and compare and analyze the images through a computer. For example, by superimposing the inspection images of bridge piers in different years, the crack expansion speed can be accurately calculated; at the same time, these data can be stored for a long time, providing traceable basis for the whole-life cycle operation and maintenance of the project, and avoiding operation and maintenance decision-making errors caused by the loss of inspection data.

From the perspective of long-term operation and maintenance, underwater inspection cameras can significantly reduce the comprehensive inspection cost of underwater projects. On the one hand, it reduces labor cost input: traditional manual inspection requires the establishment of a professional diving team, equipped with diving equipment and medical support personnel, and the cost of a single inspection is as high as tens of thousands of yuan; while an underwater inspection camera only needs 1-2 operators, the equipment can be reused, and the cost of a single inspection is only 1/5-1/3 of the traditional method. On the other hand, it avoids the surge in later maintenance costs caused by missed inspections: for example, if a subsea oil and gas pipeline misses a corrosion point due to traditional inspection, it will eventually cause a leakage accident, which not only requires bearing tens of millions of yuan in pipeline repair costs but also needs to pay huge marine pollution compensation; while an underwater inspection camera can accurately identify defects and carry out local repairs in advance, and the repair cost is only 1/10 of the total loss after the accident. In addition, the inspection process of the underwater inspection camera does not need to interrupt the normal operation of the project. For example, in the inspection of water conservancy dams, the traditional manual inspection requires closing the gates and emptying the water body, causing the hydropower station to shut down for several days and resulting in huge economic losses; while the underwater inspection camera can operate under the normal water storage and operation state of the dam, realizing "zero shutdown" inspection and minimizing the indirect losses caused by project shutdown.