Tips from Marine Units: Training Your Team to Use ROVs for SAR
Rachel Doornekamp | July 15, 2020
Submersible remotely operated vehicles or ROVs provide search and recovery teams with a safe and effective tool for the search and recovery of victims and evidence.
Specializing in identifying targets of interest, victim and evidence recovery, and rapid search response, a Deep Trekker ROV can enhance and assist search and recovery teams.
When time is of the most importance, Deep Trekker ROVs have eyes in the water in seconds. In time sensitive situations, the ROV provides real-time visuals. Add-on sonar allows for accurate and effective navigation in the turbid waters. Tailor-made tools such as additional lighting or grabber arms allow teams to retrieve victims or evidence.
The easily transportable and deployable robots allow teams to work effectively in remote and difficult locations. In an industry as potentially dangerous as search and recovery, the assistance provided by an ROV keeps divers safe and out of precarious situations.
Outlining a Plan
One of the first steps to training your team in using an ROV is to nail down your search and recovery process with the ROV. With a strong plan in mind it is easy for your team to visualize how the ROV will be used and how the vehicle will change processes.
When Shane Seagroves, Emergency Services Director of Lee County Rescue, and his team are dispatched to an incident they typically face large, open water conditions. Using side scan sonar the team begins by sweeping the area for targets. “One of the things we’ve tried to implement in our program is a methodical approach to search and recovery. We set up grids on the boat...we typically try to run in 90 degree angles, sonar does not like to run in circles,” explained Seagroves.
“We’ll start with a pattern running parallel to the shore. If we’ve got a search area we try to get out of that search area, maybe 200, 300 yards away from that...we will then do the same thing running perpendicular to the shore,” said Seagroves. “If you try to focus on one point you will develop tunnel vision and you can end up wasting a lot of time searching one area.”
After scanning the area, the Lee County Emergency Services Team rates the targets on the bottom in terms of likelihood of a match. Using the ROV, the team quickly and safely checks the targets. “You take the ROV and you can find your target pretty easily down on the bottom,” noted Seagroves. “We identify the target with the boat, so we’re using the ROV instead of having to do hops with the divers. We deploy the ROV from the boat, verify the target yes or no.”
Once the target has been identified as the victim, they must be retrieved in a respectful and safe manner. “We attach the ROV to the target and have the diver go down and do the recovery,” explained Seagroves.
Glenn Lang, Special Agent with the Maine State Police uses his ROV in a similar manner to Seagroves however being based in Maine means that Lang can often have cold, icy conditions to contend with. While side scan sonar is not an option on an icy lake, the team in Maine runs search patterns for targets similar to the way Lee County does. Starting from a hole made in the ice, Lang directs the ROV in a spokes pattern to accurately cover the area. “We keep our runs on the spokes fairly short, maybe 100 or 200 feet as opposed to really reaching out there,” he noted.
Recovery in the frozen waters can differ depending on conditions. “We then send the ROV down, it will depend on our dive team whether the commander wants to send divers under the ice to recover when we easily could recover with the ROV itself,” Lang explained. “For recovery it depends on what the commander decides.”
By ensuring that your team is clear on key processes you are setting them up for success.
Murky water is inherently dangerous to navigate within as a diver. Below the surface, visibility can range from a few feet to a few inches away; in some cases, the water is so dark you would not be able to see your hand, millimeters from your face. In conditions where visibility is dangerously low, murky water search & rescue operations are extremely difficult to perform. As it is impossible to ascertain the parameters of the dive area, safety becomes a greater concern for divers facing unknown and potential precarious conditions.
In turbid waters, the standard camera on the underwater drone will work similar to a human eye; they will have a hard time navigating through the water. This is where the navigational sonar systems come into play. From the surface, the ROV pilot navigates through the low visibility water solely using the sonar's heads up display (HUD); similar to how a pilot would rely on their plane's instruments when they fly through a fog. Add-on sonar allows for accurate and effective navigation and identification of targets in turbid or dark waters.
The benefits of pairing ROVs with sonar systems for search and rescue operations is clear. By using the sonar, either side scan sonar on a vessel or sonar directly on the ROV, you are able to quickly locate the objects or discrepancies underwater that may be the target you are searching for. From there, the ROV can be deployed to verify and retrieve, or help retrieve, the object.
In order to make the most of sonar’s ability it is imperative that teams feel confident and gain valuable experience in navigating and identifying objects with sonar. Seagroves noted that when it comes to sonar, “you have to practice.” When his team first utilized sonar nearly a decade ago Seagroves shared that, “every Friday morning at sunrise we were on the lake running that (sonar) looking at stuff. We looked at tires, we looked at bricks, we threw guns in the water, I put divers in the water, we threw dummies in the water, just trying to figure out what we were looking at.”
Seagroves noted the importance of keeping things straightforward and simple to maximize training, “use the sonar as a flashlight, keep it simple...we’re taking that dark black water and we’re turning it white.”
You can learn more about the use of sonar and different types of sonar in our Sonar for Search and Recovery ROVs.
Deep Trekker offers numerous add on tools to further assist emergency service teams. In addition to the sonar discussed above, a variety of plug and play add ons enhance the abilities of the vehicle.
The Two-Function Grabber Arm is extremely versatile and beneficial for search and recovery teams. With this grabber arm, operators can safely retrieve objects, hold tools and deploy equipment. Infinite 360 degree rotation and 32kg (70lbs) of locking force make this rugged add on a valuable tool for emergency service teams.
With the Two-Function Grabber Arm, teams can also make use of the 3-Jaw Manipulator Attachment, Interlocking Large Claw Attachment and Interlocking Small Claw Attachment for straightforward retrieval of a variety of submerged items. Seagroves went on to say that, “by using these tools we limit that risk, we limit exposure and that first recovery we made with the ROV paid for itself.”
It is imperative that teams feel comfortable with these tools in order to maximize the benefits of their use. In addition to full understanding of the tools, users should be well practiced in the use of the tools to perform well in high pressure situations.
Search and recovery missions can be dangerous and time consuming for divers, making an underwater ROV an incredibly useful tool for teams. Working in tandem with divers, ROVs provide instant eyes in the water to assist in many facets of recovery, from the quick identification of targets to the retrieval of items from dangerous locations.
“We didn’t set out to put divers out of business, we wanted to make it safer for them,” noted Seagroves. Divers and ROVs together make an excellent team for efficient and safe search and rescue operations.
In order to optimize ROV and diver operations it is imperative that divers have practice in the water with the ROV. As noted by both Seagroves and Lang, recovery can be greatly assisted by following the ROV’s tether to the target.
Deep Trekker Vehicles
Deep Trekker offers two submersible ROVs, the DTG3 and the REVOLUTION. Both vehicles offer operators with a convenient and straightforward way to get eyes underwater. Both equipped with a 4K camera, Deep Trekker’s ROVs provide users with high quality underwater footage.
The battery-operated vehicles are designed for ease of portability. Portability of an ROV is extremely important during a search and rescue mission. With bodies of water being located in some of the most remote locations on the planet, air transportation or on foot travel may be the only access. Deep Trekker vehicles come housed in their own convenient Pelican carrying cases, allowing them to be easily transported and deployed in isolated areas.
The DTG3 is a mini observation-class underwater ROV built to provide operators the ability to quickly deploy and visually inspect within underwater environments. Battery operated for up to 8 hours with a depth rating of 200m(656ft), the DTG3 is versatile and durable.
The REVOLUTION is a completely re-imagined ROV. The patented pending revolving head allows operators to rotate the camera, manipulators and sonar all while station holding in moving water. Depth rated to 305m(1000ft) with an 8 hour battery life (including quick swap), the REVOLUTION is tough and adaptable.
Ashton Davis, Houston County Rescue Chief and Board President shared that, “by far the best piece of equipment other than divers is this ROV.”
Shane Seagroves, Emergency Services Director at Lee County Rescue, echoed Davis by saying, “at the end of the day we’re looking for 3 things; safety, efficiency and timeliness. And it (Deep Trekker) hits all 3 of those for us.”
Underwater Search and Rescue Patterns You Should Know
August 30, 2021
Methodical search patterns are important to a thorough search. There are many...
ROV Pilot 101: All You Need To Know
July 30, 2021
Underwater drones were first invented in the 1950s. Their design enabled them...
Sonar Systems: All You Need to Know
April 6, 2021
Sonar systems have many applications, but what should you know? This guide...