Combining machine control and a skilled operator to help archaeology
Case study
Author: Karina Lykke Lumholt
Video specialist: Pamela Almeida
An area of about 10 hectares/25 acres is right now being excavated in Odense, Denmark, before being laid out for construction. Odense City Museums and their large team of archaeologists are responsible for researching, excavating, and preserving the prehistory of the area, and curator Jakob Bonde is leading the excavation.
“We have found parts of an existing village, which we can date back to the Middle Ages around 1200 A.D.,” explains Jakob.
South of this mediaeval site, the archaeologists were thrilled to find an even earlier site. A burial place with cremation graves from the Roman Iron Age (500 B.C. to 400 A.D.).
The digging of search trenches commences an archaeological excavation to get a sideways (layered) view of the deposits. This establishes if there are archaeological objects or material in the area and places them in chronological order.
If archaeological finds are discovered on site after the initial examination, an excavator will meticulously remove the topsoil. Thomas Petersen from the company Fuglsanggård is specialised in using an excavator equipped with Leica iXE3 machine control for archaeological projects.
“We started working with Thomas about four years ago. It is very helpful for us that he has this equipment because it’s making our job easier when we don’t have to measure everything. He can help us setting out the test trenches and the areas that we shall excavate, and when we are finished, we level everything out again,” says Jakob.
It takes finesse to use an excavator for archaeology projects
The excavator carefully removes the topsoil, and if the archaeologists find something, the Leica GS12 GNSS antenna and the CS15 controller are used to digitally record the exact positions of the find and report it back to the museum. Wooden pegs are placed in the soil so the archaeologists can look for traces of houses, pits, wells and graves in the designated area.
“I am trained in spotting the post holes, urn graves, or other graves. I know what the archaeologists are looking for, and I can stop the excavator before digging into something important. It demands patience and sense in order not to dig too deep,” says Thomas Petersen.
Thomas receives the outline with GNSS coordinates for the project from the museum, through Leica ConX to the MC1 software on the in-cabin control panel. He uses the machine control solution to log all heights of the area with the excavator’s bucket and the function Create Model in MC1 to create a surface model on the fly. The advantage is that he knows exactly how much material to fill back and where, once the excavation is finished.
Logging of points to create a surface model.
Thomas uses the newly released semi-automatic functionality in MC1 when filling back the material.
“It makes it easier to fill back material in the correct heights using the one-hand-operation. I don’t risk not having enough material, I can create a smoother surface than I can manually, and I get it right the first time!” explains Thomas.