What role can underwater robots play in deep-sea archaeology?

Let's put it this way: deep-sea archaeology is like performing delicate surgery on an "alien planet" that is pitch black, under immense pressure (enough to crush a person), and incredibly cold. Humans can't stay down there for long, and it's extremely dangerous. This is where underwater robots become the archaeologists' avatars, serving as our eyes, hands, and feet in the deep sea.

They primarily perform these tasks:

1. Acting as "Scouts" – Searching for and Discovering Targets

You've heard of finding a needle in a haystack, right? Finding a centuries-old shipwreck thousands of meters deep on the seabed is roughly as difficult. Robots are the tireless scouts for this mission.

• They are equipped with sonar systems, much like a bat's echolocation. As they navigate, they emit sound waves towards the seabed and receive the returning signals. By analyzing these signals, they can map the underwater topography. If a regular, ship-like protrusion suddenly appears on the seabed, "Bingo!" – it's very likely the target.

2. Acting as "Surveyors" – Creating 3D Archives of Sites

Finding a site doesn't mean you can immediately start excavating. Archaeology emphasizes "being fully prepared before making a move."

• The robot will circle the shipwreck or site, meticulously performing high-definition photography and 3D laser scanning, inch by inch. This is equivalent to creating an identical virtual shipwreck on a computer. Archaeologists on shore can then, like playing a 3D game, zoom in, zoom out, and rotate the ship on the computer, observing its structure from any angle, marking key areas, and planning where to excavate first and what to move later.

3. Acting as "Surgeons" – Performing Delicate Excavation Work

This is the most technically demanding part. Deep-sea artifacts, such as ceramics and wood, after centuries underwater, can be more fragile than tofu.

• Robots have very flexible "mechanical arms." Don't imagine them as large excavator claws; advanced mechanical arms perform with extreme precision. Operators on the ship, watching real-time high-definition footage, can control the mechanical arm to gently brush away silt from artifacts with a small brush, or use a specialized suction tube (like a small vacuum cleaner) to remove mud, then carefully pick up an intact plate or jar. This process requires immense patience and skill.

4. Acting as "Porters" – Salvaging and Sampling

Artifacts deemed worthy of being brought to the surface for study also rely on robots.

• The robot will use its mechanical arm to place the artifact into a specially designed basket or container with protective padding. Then, it slowly transports this basket to the surface. This process must be smooth to avoid secondary damage. It can also collect soil and seawater samples from around the shipwreck, helping scientists analyze the ancient environment.

5. Acting as "Security Guards" – Long-term Monitoring and Protection

Some sites may not be ready for excavation and are designated for in-situ preservation.

• In such cases, robots can periodically (e.g., once a year) dive to the same location to take "health check" photos of the site. By comparing photos from different periods, archaeologists can determine if the site has been damaged by ocean currents, snagged by modern fishing nets, or looted.

In summary, without underwater robots, deep-sea archaeology would largely be a fantasy. They allow us, under conditions of absolute safety, to explore and protect the treasures of human history slumbering in the dark deep sea, using scientific, rigorous, and meticulous methods.