Search and Recovery: How ROVs can aid Police Missions

The Critical Need for ROVs in Search and Recovery Operations

Searching for evidence and locating missing individuals are just a couple of the many tasks that police units are required to carry out. Search and recovery operations involve the systematic search and retrieval of evidence, objects, or individuals relevant to criminal investigations or other law enforcement operations.

While search and recovery operations may not be a daily occurrence, their importance cannot be understated. Due to the gravity of these operations, having dedicated resources such as recovery Remotely Operated Vehicles (ROVs) and dive teams is of utmost importance. In fact, many larger municipal governments have established marine units that include both ROVs and divers for precisely these purposes.

The presence of water bodies in the vast majority of counties, cities, and towns across the globe creates a potential for incidents such as drownings, evidence concealment, and drug smuggling. To effectively respond to these situations, mission-ready teams equipped with ROVs and dive capabilities are essential.

It's worth noting that the rarity of these incidents should not undermine the need for preparedness. In fact, the absence of resources to address underwater situations can inadvertently increase the likelihood of illegal activities taking place. If lawbreakers are aware that police units lack the means to recover evidence from water, they may be emboldened to engage in illicit acts beneath the surface. Therefore, having dive teams and ROVs readily available not only serves as a response tool but also acts as a preventive measure.

Challenges of Traditional Method of Search and Recovery

Traditional methods for search and recovery missions typically involve the use of dive teams. These methods face many challenges, including:

The safety of dive teams working in dangerous environments
Time and depth restrictions
Search inaccuracy
Deployment requirements of a minimum of three people (two to supervise the diver)
Cost

Before teams adopted the use of search and rescue ROVs and sonar to aid in searches, divers would have to rely on their vision, if possible, or by touch, if visibility was restricted. This process is incredibly time-consuming, requiring slow, methodical searches of small areas at a time, and poses an increased risk to divers due to extended amounts of time underwater.

Visibility Challenges in Traditional Methods

Search sites are often in treacherous waters, leaving dive teams to work in inherently dangerous environments. They are ultimately putting their lives at risk every time they splash into unknown, or turbid waters.

Limerick Marine Search and Rescue Service, using a Deep Trekker ROV to assist divers in SAR operations, says, "No one wants to see rescuers injured or lose their lives during a rescue or recovery mission," explains Mr. Sherlock, treasurer of LMSRS. “We wouldn’t be entering a diver in water that has speeds of four knots, but we can enter this unit at four knots, that would be at its maximum speed. This will negate the chance of us putting a diver into the water to endanger themselves going into a dangerous area.”

The potential to encounter structures that could pose a safety risk, or objects that could entangle them and trap them underwater is potentially high. Diving into unfamiliar waters that may have low visibility due to being murky creates an unnecessary risk that can now be avoided with the use of recovery ROVs and sonar technology.

Discover the Impact of Underwater Drones in Murky Water Search and Rescue Operations. Explore the Cost-Effective and Safer Alternative.

Poor visibility can be caused by factors like sediment, algae, debris, or water turbidity, making searches in these environments through traditional methods very difficult and potentially dangerous.

Depth Limitations and Deployment Constraints

Police divers are limited to a maximum depth of 100 feet (30m) in any body of water. Anything beyond this depth and dives become much more dangerous and complicated, with a high risk of central nervous system oxygen toxicity convulsions and nitrogen narcosis, as well as the need for divers to go through decompression, which can take hours, after only a 15 minute dive. This limitation can make conducting thorough searches difficult, especially when search areas can be quite large and need to be covered as quickly as possible.

Divers need to be back to the surface with a minimum of 1000 psi for all dives. The average diver breathes with a 20-35 psi/min Surface Air Consumption rate in a no current dive, and in just a 1.5 knot current, that SAC rate can be as much as 4-5 times higher.

Short deployment time is also a challenge and can slow an entire mission down. Many search and recovery missions take hours or even days to complete, since divers are limited in the amount of time they can spend underwater.

In some situations, especially in extreme cold or heat environments, divers can only remain underwater for less than 30 minutes before having to resurface and take an extended break. Anything over the 30 minute mark can compromise the diver’s optimal physical and mental condition, making searches less effective while also putting the diver’s health at risk.

Scuba Diver in the Water with DTG3's

Search Inaccuracy and Complex Underwater Environments

Traditional search and recovery methods rely heavily on human divers and their manual search efforts. Because these searches are typically conducted in large areas and are commonly quite dangerous and complex, search accuracy becomes a major challenge of police units conducting these operations.

Search inaccuracy can be due to a variety of reasons, such as:

Limited visibility
Complex underwater environments
Search area size
Human error

Limited visibility is one of the most common challenges, with many searches being conducted in high current, or murky waters. In murky water, divers must rely on touch, making it extremely easy to pass by an object of interest without realizing it. In high current, divers often use drift diving, which involves deploying divers upstream from the search where they are then carried by the current while conducting their search. This, of course, creates limitations and leads to inaccuracies, since it becomes much easier to miss something while drifting with the current.

Complex underwater environments can also make it very easy to miss objects of interest, since divers need to sift through many objects and obstructions, which can impair their search and make it difficult to avoid passing over a target that might be obscured by many other objects.

Search area size is also an important factor that can easily lead to inaccuracies. Without the aid of an ROV for law enforcement that can track and mark areas through a mission planner and tracking software, divers are left to rely on their memory and slow, methodical searches in small areas that can easily lead to missed areas. Human error is always a factor in any mission, but can be mitigated by the aid of technologies and tools like sonar and ROVs that can help make these challenging operations more accurate and successful.

“When we are diving we may miss something alongside us that might be only three feet away, whereas this drone is breaking down that barrier of misses,” Mr. Sherlock explained.

Half Surface Half Underwater

Cost Considerations in Traditional Methods

Dive teams are more than just the men and women in the water - they also require multiple dive supervisors, especially in HAZMAT or deeper water scenarios. For smaller municipalities, this may mean a significant portion of the law enforcement, or the need for volunteers.

The cost is a substantial consideration for police units. Divers require training and certification, the equipment is incredibly expensive, and the cost of insurance is even more. For example, insuring a single diver for a year usually sits at around $25,000 USD due to the associated risks that come with their job. Many regions rely on volunteers for search missions; however, there is no reason to risk a person's life if alternatives are available, especially if they are not being compensated for their efforts.

The length and frequency of dives can also affect the costs associated with these police operations, due to the costs involved with managing and preserving the air supply. Tanks need to be refilled with compressed air or breathing gas after every dive, and the cost to refill can vary depending on the location. Some dive centers will charge a flat fee to refill, while others will charge a fee based on the volume of air or gas needed to refill.

The cost of a single recovery ROV equipped with sonar could offset these costs within a single year of use, and with little to no maintenance required, that one purchase could last municipalities for many years, drastically reducing their operational costs while at the same time massively improving the speed and accuracy of their searches.

Search and Rescue Tent

Advantages of Using ROVs in Search and Recovery

An ROV for law enforcement is utilized for search and recovery operations for several reasons. There are many benefits for multiple applications, including:

Training and safety for divers
Extended dive time
Deepwater searches
Advanced imaging and sensor capabilities
Documentation and evidence preservation
Target recovery

These capabilities make an ROV in municipalities an incredibly valuable tool for law enforcement agencies in conducting effective and efficient search and recovery operations in underwater environments. When speed and accuracy are so crucial to mission success, police units need to leverage every advantage available to them.

Enhancing Diver Training and Safety

ROVs can be integrated into diver training programs for search and recovery, providing controlled and adaptable training environments. .

Divers can benefit from gaining valuable experience, developing specific skills, and enhancing their overall proficiency by working with the support of ROVs, maximizing the effectiveness of law enforcement diver training programs.

ROVs can record real-time data, provide top surface assistance, and collect data for post dive reviews, which will help further develop the efficacy of dives.

Improved Diver Monitoring and Assistance

Not only can ROVs enhance diver training, but also diver monitoring and assistance during actual search and recovery missions. Police units can take advantage of the capabilities of ROVs and significantly improve the safety, efficiency, and effectiveness of underwater search and recovery operations with these tools.

Supervisors can give topside support by providing better situational awareness through real-time monitoring of diver activity through the ROVs high resolution cameras and sonar to ensure the safety of the divers. Integrated with sonar, police units can use ROVs to communicate real time situational awareness, an invaluable complement to the divers that dramatically enhances the safety of the mission.

ROVs can also be deployed while divers prepare to splash, which, again offers better situational awareness, as well as helping to minimize the time spent underwater by mapping out the area in advance, and even locating and helping to navigate to the target. When time is so crucial to mission success, having access to tools that can save considerable time and allow operators to quickly assess an area is a huge benefit to search and recovery operations.

Efficient Target Recovery

Equipped with robotic arms, grabber claws, or specialized tools, recovery ROVs can securely grab and retrieve objects of interest from underwater environments. With robotic arms, operators are able to grab and manipulate objects, place them in recovery positions or baskets, or attach targets to carabiners and lift lines for retrieval.

This provides a safe and controlled method of recovery of the target, often protecting divers from having to make difficult and potentially dangerous dives. It also provides a better understanding of the search area, and accompanied with rescue boats, adds an extra layer of security for police units and dive teams.

“It is powerful enough to retrieve people, it has the strength to lift a person, it won’t let it go," says Mr. Sherlock.

Pivot-005

Streamlined Body Recovery

When faced with the devastating task of searching for a missing person, missions are incredibly time sensitive. Police teams have a finite amount of time to find these lost souls and to try to bring some level of closure for families and loved ones.

With ROVs to aid the police units, teams gain the advantage of real time visuals, and accurate, highly effective navigation when adding sonar systems to the ROV to provide detailed information of the environment, even in low visibility, murky water.

When working in high current waters, police teams can use USBL and DVL modular add-ons for additional situational awareness, stability, and station holding, allowing ROVs to counter currents easily. Divers can also follow the ROVs tether to the location, once the ROV has found the target, helping divers work and navigate more safely in difficult and dangerous environments.

Evidence Preservation and Recovery

Using ROVs in municipalities to help recover evidence comes with many benefits. Most importantly, perhaps, is the ability to conduct the search without disturbing crucial evidence. ROVs can capture detailed imagery and video footage, and this documentation can provide a valuable record for investigations while preserving the integrity of the evidence without causing damage or disturbance. Splashing divers into unknown waters always comes with the risk of accidentally destroying or disturbing evidence, as well as having elevated safety concerns.

The safety of the team is equally important, and using recovery ROVs allows police units and divers to gain situational awareness, especially with the integration of sonar and mission tracking software. Operators can leverage the moving map display and track the last searched areas to help complete searches much faster, with more accuracy, and with more efficiency.

Additional Advantages of Utilizing ROVs

There are many more advantages to utilizing ROVs with police search and recovery teams, including, but not limited to:

Cost effectiveness - save on costly diving equipment, dive insurance, and unnecessary dives.
The ability to dive and search much lower depths than human divers.
Conducting preliminary searches of an area to help pre-plan dives.

Enhancing Search and Recovery Operations with Deep Trekker ROVs

Deep Trekker ROVs are effective and useful tools for police search and recovery units that are easy to learn and operate, with the advantage of being optimized for sonar operations. Proven to be successful in identifying targets of interest, victim and evidence recovery, and rapid search response, a Deep Trekker ROV enhances and assists police search and recovery teams, while saving a considerable amount of time and money.

Quick Deployment and Real-Time Visuals

Deep Trekker underwater drones can be deployed in a matter of seconds, allowing police teams to get eyes in the water almost immediately. When time is so mission critical, this advantage couldn’t be more important. Providing real time visuals quickly and safely, with modular integrations such as sonar, additional lighting, and grabber claws, police teams are able to quickly locate and retrieve victims or evidence.

BRIDGE Technology for Enhanced Integration and Data Recording

Deep Trekker's BRIDGE technology offers operators the ability to integrate imaging sonars and USBL positioning system data via the handheld controller. Operators can view this information on the controller screen and record video, sensor data, sonar data, and USBL data in one place. The USBL can time stamp position data, which can be exported for easy analysis after a dive. This eliminates the need for bulky equipment and streamlines operations for ROV pilots, enhancing their efficiency and effectiveness.

ROVs or underwater drones equipped with Sonar and USBL systems can greatly assist with performance in murky waters.

Portability and Remote Operation

Deep Trekker ROVs are designed for portability, enabling effective operation in remote locations. The robots' ease of deployment and portability make them ideal for accessing challenging and isolated areas during police search and recovery missions. Their compact size and convenient Pelican carrying cases allow for easy transportation and deployment, ensuring that teams can work effectively even in hard-to-reach locations.

Versatile ROV Options

Deep Trekker offers three underwater ROV models: DTG3, PIVOT, and REVOLUTION. These purpose-built and customizable ROVs are engineered to meet various needs across industries, including police search and recovery. Equipped with sonar and a 4K camera, Deep Trekker’s ROVs are able to deliver high quality underwater footage and detailed imagery in practically any environment. ROVs can also provide assistance with side scan sonar and greatly improve the long range capabilities of the search.

ROV Family

The DTG3 is a mini observation-class ROV designed for quick deployment and visual inspections in underwater environments. The PIVOT and REVOLUTION models feature six vectored thrusters for enhanced maneuverability and stability. The REVOLUTION's patented revolving head allows for camera, manipulator, and sonar rotation while station holding in moving water. These ROVs have impressive depth ratings and battery lives, making them tough, portable, and adaptable for diverse operational requirements.

Ensuring Diver Safety and Efficiency

Deep Trekker ROVs play a vital role in keeping divers safe during risky search and recovery operations. By utilizing ROVs, police teams can reduce the risks associated with diving, such as working under ice or in dangerous conditions. The ROVs provide a safer alternative, preserving the lives of divers while efficiently completing the mission. The use of ROVs is seen as an imperative step in minimizing the unacceptable loss of divers during high-risk operations.

Maine State Police Special Agent Glenn Lang shares, “You’re not replacing them (divers), it makes them safer and preserves the lives of divers because it can be so hazardous going under the ice...25 years ago I lost one of my friends who was diving under the ice, it’s just that risky...losing divers that way is just unacceptable when you can take care of it without putting a man under the ice.”

Expert Guidance and Customization

Deep Trekker offers robotics experts who can assist in finding the right technology for specific missions. They provide guidance and support to help select the appropriate ROV option based on applications and budget. The team is dedicated to helping police units maximize the effectiveness of their search and recovery operations. Custom quotes can be obtained to tailor the solution to individual needs.

If you need help finding the right technology for your missions, reach out to our robotics experts to find the right option for your applications and budget. We are happy to help. Get your custom quote today.