Application Practice of Remote Acoustic Devices on Unmanned Ships

With the rapid development of unmanned ship technology in maritime operations, security patrols, ecological monitoring, and other fields, its characteristics of autonomous navigation and long - term endurance have become important supports for water operations. However, the traditional functions of unmanned ships mostly focus on data collection such as water quality testing and image monitoring, and they lack efficient water sound interaction and deterrence capabilities. Relying on the core advantages of directional sound transmission and resistance to water environment interference, remote acoustic devices form a "water mobile acoustic platform" with unmanned ships, effectively making up for the shortcoming of unmanned ship sound interaction and further expanding their application value in complex water scenarios.

I. Application Scenarios of Remote Acoustic Devices Adapted to Unmanned Ships

The combination of remote acoustic devices and unmanned ships accurately matches the following four core water scenarios to solve the operation pain points in different fields:

• Maritime security and border patrol scenarios: In areas such as coastal borders and inland waterways, unmanned ships equipped with remote acoustic devices can issue directional warnings to illegal smuggling ships and stowaway ships (such as "Your ship has entered China's jurisdiction waters, please stop immediately for inspection"). In key areas such as ports and docks, they can broadcast safety management notices in real - time (such as "Staying in the waterway is prohibited, please pay attention to avoiding passing ships") and synchronize the on - site dynamics to the ground command center to assist law enforcement personnel in handling.
• Emergency rescue scenarios: When people are trapped in water due to disasters such as floods and typhoons, unmanned ships can quickly reach the disaster - stricken waters. Through remote acoustic devices, they can broadcast rescue routes to the trapped people (such as "Please move to the direction of the orange life raft, and the rescue ship is on standby nearby") and deliver knowledge on floating and risk avoidance. In maritime search and rescue, they can play positioning prompts to the people who fall into the water (such as "Save your strength, and the unmanned ship will drop life - saving equipment for you") and assist the rescue team in locking the target position through sound signals. In oil spill accidents, they can broadcast the scope of the dangerous area to the surrounding ships (such as "There is an oil spill in the XX waters, please do not approach") to avoid secondary accidents.
• Ecological protection and water management scenarios: In water areas of nature reserves (such as wetlands and lakes), unmanned ships equipped with remote acoustic devices can broadcast warning voices to illegal fishing boats and illegal sewage - discharging ships to form water deterrence. In areas such as reservoirs and drinking water sources, they can broadcast prohibition notices to people who swim and fish in violation of regulations (such as "This is a drinking water source protection area, and entering the water is prohibited"). In aquaculture areas, they can repel harmful aquatic organisms through specific frequency sound waves to protect the safety of aquaculture species.
• Public services and operation coordination scenarios: At the site of water construction (such as bridge construction and waterway dredging), unmanned ships can broadcast the scope of the construction area and the detour route to the passing ships through remote acoustic devices (such as "Please detour 100 meters north of the construction area, thank you for your cooperation"). During water events (such as dragon boat races and sailing races), they can broadcast the competition rules and safety tips in real - time (such as "Non - event ships are prohibited from entering the race track during the competition") to maintain the on - site order.

II. Core Customer Needs in Unmanned Ship Scenarios

In the application of unmanned ships, customers' needs for remote acoustic devices revolve around "water resistance, stability, and efficiency", which are specifically manifested as follows:

• Strong water resistance and environmental adaptability needs: Unmanned ships operate on water for a long time, so the device is required to have a protection level of IP65 or above, which can resist seawater corrosion, rain immersion, and wave impact. At the same time, it should adapt to the changes in water temperature and air temperature in the range of - 20°C to 60°C to avoid faults in environments such as high - temperature exposure and low - temperature freezing. In addition, it should have wind and wave resistance capabilities and can transmit sound stably under wind force below level 5 without being covered by environmental noise (such as wave sound and engine noise).
• Long - distance clear sound transmission needs: The operation range of unmanned ships is mostly 1 - 5 kilometers of water area. Therefore, the device is required to have an effective sound transmission distance of not less than 800 meters in an open water area without obstacles. The voice signal has no distortion and no noise. Even in a windy and rough environment, the personnel on the water can clearly receive the information. For specific targets (such as a single ship and a single trapped person), it is required to have the ability of directional sound transmission to avoid sound diffusion interfering with unrelated areas.
• Remote control and coordination needs: It supports remote operation through the unmanned ship control system or the shore - based command platform, including volume adjustment, working mode switching (directional/omnidirectional), pre - made voice playback, and real - time voice input. No manual boarding is required for setting. At the same time, it needs to be linked with the unmanned ship's GPS positioning, high - definition camera, and sonar sensor. When the sensor detects a target (such as trapped people and illegal ships), it automatically triggers the acoustic device to work.
• Low power consumption and endurance adaptation needs: The single - operation endurance of unmanned ships is mostly 8 - 24 hours. Therefore, the device is required to have low - power consumption characteristics, with a working power consumption of less than 15W. It can be directly connected to the unmanned ship's power supply system to avoid affecting the operation due to frequent charging. At the same time, it should have a power monitoring function. When the device power is too low, it automatically sends a reminder to the command platform to ensure that the key information transmission is not interrupted.

III. Core Characteristics of Remote Acoustic Devices Adapted to Unmanned Ships

To meet the needs of unmanned ship scenarios, remote acoustic devices need to have the following targeted technical characteristics to ensure efficient collaboration with unmanned ships:

• High protection and anti - corrosion design: The shell is made of aluminum alloy or engineering plastic + anti - corrosion coating material, which can resist the corrosion of seawater and fresh water and avoid rusting and cracking due to long - term immersion. The equipment interface adopts a waterproof sealing structure, and the data cables and power cables are equipped with waterproof connectors to prevent water from seeping into the internal circuit. At the same time, a moisture - proof and breathable valve is set inside the device to balance the internal and external air pressure and avoid the generation of condensed water.
• High sound pressure level and anti - interference output: The sound pressure level output can reach 130dB - 150dB, covering the human ear - sensitive frequency band of 200Hz - 20000Hz to ensure that the sound signal can still penetrate the interference in environments such as wave sound and engine noise. A professional acoustic algorithm is used to optimize the sound wave transmission path to reduce the attenuation of sound caused by water surface reflection. Even in an environment with 1 - meter - high waves, the voice information can still be clearly received at 800 meters. At the same time, it supports more than 10 levels of sound intensity adjustment to adapt to the needs of different scenarios.
• Low power consumption and multi - power adaptation: A low - power chip and an energy - saving circuit design are adopted. The standby power consumption is less than 3W, and the working power consumption is controlled at 10 - 15W. It can be directly connected to the unmanned ship's lithium battery or solar power supply system without an additional backup power supply. Some devices have a built - in backup lithium battery, which can maintain the continuous operation of the device for more than 3 hours when the unmanned ship's power supply is interrupted, ensuring the information transmission in emergency situations.
• Lightweight and easy - installation design: The overall weight of the device is controlled within 5 kilograms, and the volume is not more than 20cm×20cm×20cm. It can be fixed on the deck or the top of the cabin of the unmanned ship through a bracket without affecting the navigation stability and load - carrying capacity of the unmanned ship. The installation interface adopts a standardized design, supporting quick disassembly and replacement to facilitate later maintenance and overhaul.

IV. Integration Solutions of Remote Acoustic Devices with Other Equipment

In the unmanned ship system, remote acoustic devices need to be integrated with a variety of equipment to form a "perception - decision - execution" collaborative system. The specific integration solutions are as follows:

• Integration with perception equipment: It is linked with the unmanned ship's high - definition camera, sonar sensor, and infrared thermal imager. When the camera identifies abnormal situations such as "illegal ship intrusion" and "person falling into the water", or the sonar detects underwater obstacles and illegal fishing equipment, it automatically triggers the remote acoustic device to play the corresponding voice (such as "Your ship has illegally intruded into the no - navigation area, please leave immediately" and "A person falling into the water is found, and the unmanned ship will go to the rescue"). The infrared thermal imager can assist in locking the target in the environment of night or low visibility to ensure that the device transmits sound accurately.
• Integration with communication equipment: It is connected to the unmanned ship's 4G/5G communication module or satellite communication module to realize ultra - long - distance control. When the unmanned ship operates in waters far from the shore and without public network signals (such as the open sea), the shore - based personnel can send commands (such as switching the working mode and updating the pre - made voice) to the acoustic device through the satellite link. The device can transmit the working status (such as power, volume, and fault information) back to the shore - based command platform in real - time to facilitate remote monitoring and fault troubleshooting.
• Integration with positioning and navigation equipment: Combined with the unmanned ship's GPS/Beidou positioning system, when the unmanned ship enters a preset sensitive area (such as a drinking water source protection area and a military no - navigation area), the remote acoustic device broadcasts a warning voice to the ships entering this area. When the unmanned ship deviates from the operation route (such as deviating from the search and rescue area due to wind and waves), the device immediately sends a position abnormality alarm to the shore - based platform and plays the prompt of "The unmanned ship deviates from the route, please pay attention to avoidance" to the surrounding ships.
• Integration with warning light equipment: It is linked with the unmanned ship's LED warning light and strobe light to form a "sound and light coordination" effect. When the remote acoustic device starts the warning mode, the warning light is turned on synchronously (such as a blue strobe light). Through the dual stimulation of vision and hearing, the warning effect on the target is enhanced. For example, in night rescue, "sound and light coordination" can help the people who fall into the water quickly locate the position of the unmanned ship and improve the rescue efficiency.

V. Core Advantages of the Combination of Remote Acoustic Devices and Unmanned Ships

Compared with traditional water acoustic devices or unmanned ships operating alone, the combination of remote acoustic devices and unmanned ships can exert significant advantages in many aspects:

• Expand the operation range and efficiency: Unmanned ships can autonomously navigate and cover a large - area water area (a single operation can cover more than 20 square kilometers). Combined with remote acoustic devices, the information transmission efficiency is 4 - 6 times higher than that of manual ship - driving broadcasting. For example, in the management of a 10 - square - kilometer reservoir, unmanned ships combined with devices can complete the broadcasting of the no - swimming notice in the whole water area within 2 hours, while manual ship - driving takes 6 - 8 hours.
• Improve operation safety: In dangerous scenarios (such as flood - stricken areas and oil spill waters), unmanned ships can replace personnel to enter high - risk areas for operation. Remote acoustic devices allow shore - based personnel to complete information transmission and deterrence without approaching dangerous environments, greatly reducing the risk of personnel casualties. For example, in the water rescue after a typhoon, unmanned ships carry devices to enter the waters with strong wind and waves to broadcast rescue instructions, avoiding the risk of the rescue personnel taking risks by driving ships.
• Realize precise and ecological operation: Through the directional sound transmission technology and the precise positioning ability of unmanned ships, the sound can be accurately transmitted to the target area, avoiding environmental interference caused by sound diffusion to the surrounding ecological environment. For example, in the water area of a nature reserve, warnings can be broadcast directionally to illegal fishing ships without affecting the habitat of the surrounding aquatic organisms. At the same time, the device can simulate the sound of natural enemies to achieve ecological repelling, avoiding water pollution caused by the use of chemical agents.
• Reduce operation costs: One unmanned ship combined with a remote acoustic device can replace the workload of 2 - 3 water operation personnel. Moreover, the single operation cost (electricity fee, maintenance fee) of the unmanned ship is lower than the cost of manual ship - driving. Long - term operation can significantly reduce the investment in labor and time. For example, in the daily security patrol of the port, one unmanned ship can cover the patrol needs of a 5 - kilometer waterway, and the cost is reduced by more than 50% compared with manual ship - driving patrols.

VI. Application Cases of Remote Acoustic Devices on Unmanned Ships

Case 1: Collaborative Application of Coastal Border Unmanned Ship Patrols and Remote Acoustic Devices

A coastal border management department introduced 8 unmanned patrol ships, each equipped with a remote acoustic device, as well as a high - definition camera, a Beidou positioning system, and a satellite communication module. During daily patrols, the unmanned ships cruise in the border waters according to the preset routes. When the camera identifies a suspicious ship approaching the border line, the remote acoustic device automatically switches to the directional mode and plays the warning voice of "Your ship has approached China's border line, please turn around and leave immediately, otherwise further measures will be taken" to the suspicious ship. If the suspicious ship refuses to leave, the device synchronizes the ship's position and course information to the shore - based command center through the satellite link. The command center can remotely adjust the device volume to continuously strengthen the warning intensity. In addition, when manual patrols cannot be carried out due to bad weather (such as heavy rain and heavy fog), the unmanned ships can still operate normally and broadcast the border management regulations to the passing ships through the device to prevent illegal border crossing incidents. After the implementation of this scheme, the number of illegal border crossing incidents in the border waters decreased by 75%, and the patrol cost was reduced by 60% compared with manual ship - driving.

Case 2: Practical Application of Urban Waterlogging Emergency Rescue Unmanned Ships and Remote Acoustic Devices

When a city suffered waterlogging disasters caused by heavy rainfall, the rescue team put 5 emergency rescue unmanned ships into use. Each unmanned ship was equipped with a remote acoustic device, an infrared thermal imager, and a life - saving equipment dropping device. The unmanned ships quickly entered the flooded streets and community waters. When the infrared thermal imager detected trapped people on the roof and balcony, the remote acoustic device was activated immediately and played the instruction of "Please stay at a high place for rescue, the unmanned ship will drop life jackets and food for you, please do not enter the water without permission" to the trapped people. At the same time, the device transmitted the location information of the trapped people back to the rescue command center through the 4G communication module to assist in arranging the rescue team. In the dangerous area where the water depth exceeds 1.5 meters, the unmanned ships broadcast the warning of "The water flow here is fast, please do not approach" to the surrounding people through the device to prevent people from entering the dangerous waters by mistake. In this rescue, the combination of the remote acoustic device and the unmanned ship helped the rescue team transfer more than 230 trapped people within 4 hours. The information transmission efficiency was 10 times higher than that of the traditional loudspeaker, and no rescue personnel were injured.