Digitizing Ice: 3D Twins of the Franklin Expedition

In 1845, HMS Erebus and HMS Terror set sail for the Arctic to chart the Northwest Passage. They never returned. For 170 years, the fate of the crew was a legend wrapped in ice. Today, digital archaeology allows researchers to explore these shipwrecks without getting wet, using underwater photogrammetry and three-dimensional models to unravel the mystery from a screen.

Underwater Photogrammetry: The Robotic Eye in the Darkness 🧊

Documenting a shipwreck in the Arctic involves extreme conditions: zero visibility, freezing temperatures, and unpredictable currents. To overcome this, Parks Canada teams deployed remotely operated vehicles (ROVs) equipped with high-resolution cameras. By capturing thousands of overlapping images, a Structure from Motion (SfM) process was applied. This algorithm calculates the position of each pixel to generate a dense point cloud. The result is a textured 3D model of HMS Erebus, allowing measurement of hull deformation or identification of tool marks without disturbing the sediment.

The Virtual Puzzle: Solving the Mystery Without Touching the Ship 🔍

Creating digital twins not only preserves heritage but also enables non-invasive forensic research. Archaeologists can simulate sunlight on the model to search for hidden inscriptions in the wood. Additionally, by merging LiDAR data from the seabed with the 3D reconstructions of the ships, they study how the ice crushed the hulls. Every pixel reveals a clue: from the tin of food cans to the position of the cannons, helping to decipher whether it was lead poisoning, scurvy, or the cold that ended the expedition.

What mesh resolution do you consider sufficient to preserve these details?