Archaeology and Ancient History: Digital Archaeology, Virtual Reality in Archaeology - Lund University

You can learn most of the workflows presented in this blog joining this course!
It is not required any pre-knowledge of any 3D or 2D software... and  well.. you should see the results of our students at the end of the course...



Archaeology and Ancient History: Digital Archaeology, Virtual Reality in Archaeology - Lund University

Omnidirectionla treadmill

Some months ago, the virtual reality group at the Humanities lab went to visit a company called MSE in Älmhult. They specialize in training setups for virtual environments and they have developed an interesting product that is a sort of an omnidirectional treadmill. So the user can control moving around in a virtual world just by walking or running. There is no need for any interaction devices such as mouse, keyboard or game controller, at least not as far as moving around in the virtual worlds is concerned.

Their setup was a cylindrical projection surface around the treadmill. They also used a simple tracking device that required a small wireless transmitter attached to the user.

The obvious drawback with a device like this is of course that it can only be one user at the time, which probably means that museums won’t be that interested in it. Another drawback that became very clear once we started to try it out, was that it was really loud. MSE told us that it could be soundproofed, but there will still be considerable noise from it. 

We also tried a head mounted display that was surprisingly good. They told us that the new version of that particular head mounted display will be released in June and it will be wireless with a weight of only 350 grams. Imaging combining a head mounted display with the omnidirectional treadmill. Then you wouldn't need any other projection device and could walk around in a virtual world for quite some time.

It was a great day and we really had a lot of fun trying out their stuff. We hope to be able to collaborate with MSE a lot in the future.

Pompeii - a 3D Revival

Pompeii - a 3D Revival is a project that aims to investigate, document and visualize Pompeian architecture by means of different types of 3D-models (both in "as is- and "as was"-models). The use of acquisition techniques like 3D Scanning or Dense stereo reconstruction will increase the knowledge of the relations between the technological infrastructures of the insula i.e. water pipes system, illumination etc. and the distribution of commercial, working and reception spaces in this overall domestic context. 

Through the use of Virtual Reality Techniques will be possible to visit the Pompeian houses of Casa del Torello and Casa di Cecilio Giocondo understanding the relation between the actual archaeological context and their original appearance.

This project is very exciting and we are planning to use the results of this research activity in several ways. Last October we finished the acquisition campaign, and in collaboration with the Visual Computing Lab , Pisa , we are now post processing the data. The results of this work will serve two different visualization platforms, one specifically designed to show the structures of the insula in high resolution through the web (the main idea is make these data available to the scientific community) , and another one to support an exhibition on the insula V 1, which will take place in Stockholm in the 2014.

During the last fall we tried to visualize part of the structures inside a CAVE system, the experiment was very successful.   As you can see from this short movie, even if the house was only partially texturized, the potentialities in such application are enormous.

I'll post new results and information soon...

Best

/nicoló

Interesting and useful new tool

Centre for Image Analysis at Uppsala university has developed a very interesting tool that could be used for historical datasets. It is used to piece fragments of an object together and reconstruct the object. The obvius use could be for pottery or human bones, espacially sculls. The input to the system is 3d-scans of the different pieces. The software analysis the pieces and makes an rough alignment. Then with the help of a haptic device the researcher can put the pieces together and try to make them fit exactly.
This would be useful when working with very fragile objects that shouldn't be touched too much. Just 3d-scan them and then put the scans in this system and once it is there, they can be handled without risking any damage to the objects.
The Humanities lab sent them three pieces of a clay plate to test the system. Here is a video showing how the system is used.

http://www.youtube.com/watch?v=m1EcVWRiPT0

We will soon send them 15 pieces of a scull that will be very interesting to see if the system can handle as well.

/Stefan

Visualizations for an exhibition

The Humanities lab are involved in a really interesting project at the moment. We work together with the Historical museum in Stockholm in preparing an exhibition that will start next year. Part of it is about the battle of Visby in 1361. Visby is the largest city of Gotland, which is a big island to the east of Sweden. In 1361 it was invaded by the Danish army and in the middle of the summer there was a terrible battle just outside of Visby. The local army, consisting mainly of peasants, boys and older men, was no match for the professional and experienced Danish army and it is estimated that 50% of the male population at Gotland at the time was killed in the battle.

A skull with 11 damages from three different weapons

The exhibition will tell an exciting, but also horrible and nasty story about how people was sacrificed, died, and was buried in several mass graves outside the city wall. The skeletal remains in the graves bear witness of terrible wounds. What happened on the battlefield? How was it to be in the heat of battle, cornered between the high wall and the Danish army? The Historical museum would like to envisage some of this and we are helping out with part of the visualizations. 

A chopped off foot

First we are 3d-scanning some of the skeletal remains with clear traces of different weapons. It is three skulls, one arm, one leg and a chopped off foot. We are using a NextEngine scanner to do this job. Just to make sure, we have taken a lot of pictures as well, that could be used in PhotoScan.

The museum has hired an expert in medieval weaponry and weapon techniques and he has analyzed the wounds very carefully. Based on this analysis he could reenact the most probable movements with the most probable weapons used to inflict the different wounds. We, of course, put him in our motion capture system to record these movements so we can use them as a base for the animations that will be done to visualize what happened. 

The long axe is prepared with mocap markers

 /Stefan

4DGIS-ongoing experiments

During these days I am playing a bit with the data from Catalhoyök and Uppåkra, in both cases I am experimenting  with Image Based Modeling techniques and Arcscene 10, with the goal to have a clear idea on what the limits and potentialities.
After a long discussion with Camilla Mazzucato from Oxford University we started implementing more models and we are planning -together with a larger group of researchers- to start working on the design of a new typology of database.
So far we grouped the models in multi patch files, but I am not jet sure if this will be the best or the only solution for this project, in fact it depends a lot from the typology of visualization that we want to reach.

3D models realized during the excavation season 2012 in Catalhöyuk

Next spring's main goal,  it will be  the import of  the entire dataset of models realized during the last excavation season,  with the goal of start working  on new workflows to combine into ArcGis data of different typology (vector+3D models etc). In particular I would like for the next excavation season to explore the possibility to have a 3D distribution of findings (as points) visualized on the 3D models, let's see how far we will go..


/n

3D-scanning in the jungle

Cave entrance seen from first chamber

At the end of May I went to Belize to work at a Maya site out in the jungle for three weeks. The site, originally referred as “Awe Caves”, is a medium-sized Maya ceremonial center located in the western part of Belize. It is of particular interest because a large cave with an extensive dark zone tunnel system resides directly beneath the largest temple in the site core. The project of 3D documentation and reconstruction of this site is part of a larger research project of preliminary investigation started in the summer 2011 and directed by Holley Moyes, UC Merced. The first year some 3D documentation of the excavations was done by Fabrizio Galeazzi, UC Merced. This year one of the ambitions was to 3D-scan the complete cave. The cave is a natural geological structure, but has been divided into nine chambers in succession, by the Mayan people. The cave turns around so that the last chamber enters into the first, about 10-15 meters up on one of the walls in the entrance chamber. The different division of the chambers varies from clearly manmade structures to more or less natural boundaries.

Snapshot from pointscloud. The colored area shows a manmade wall

The 3d scanning was done with a Faro Focus 3D scanner. It is a small and compact scanner, that is easy to carry and has everything needed to scan built in. Faro Focus 3D including tripod, weighs about 8 kg and is therefore the ideal scanner for a mission of this kind. One important benefit from the small format of the scanner is evident in the fact that the scanning of the complete cave were made in just eight days.

Scanning of excavtion in the cave was done with light

Right from the beginning it was decided not to try to capture color information in the cave, but only settle for the geometry. To capture color information would demand large amounts of lights to illuminate the cave properly. Bringing enough lights and spending time placing them as good as possible would have been a huge and costly task far beyond the scope of the project.

At the start of the campaign, a fairly normal scanning strategy for larger structures was applied. This was a relatively efficient approach in the entrance chamber, but further into the cave it got more and more difficult. With such an extremely irregular geometric structure found in the cave, the risk to miss important parts was much larger than usual. So after a few days the scanning strategy significantly changed and scanning positions were moved closer together to be sure to cover as much as possible. It culminated in the fifth chamber, which was a complete jumble of rocks, stalactites, stalagmites, narrow cavities and hidden structures. This complex geometry led to a scanning strategy, in which the different scan positions were placed only a few meters from each other. This of course gave us a huge amount of scans that, at this writing, still isn’t fully post processed. 

The humidity caused other problems as well

Another objective of the scanning campaign was to verify how well the scanner handled the very special climate prevailing in a place like this. This is subtropical jungle and the work were made during a time of year when it was quite a lot of rain, high humidity and relatively warm. Inside the cave the temperature was slightly lower, but the humidity was significant. Anyone who has worked with electrical equipment in these conditions can tell you that humidity plays tricks with equipment that does not occur in dryer environments. 

Scanning part of the entrance from a spot in the jungle

We were pleased to see that the scanner handled these conditions well for most of the time. The battery ran out faster than usual, but that was expected. The only problem experienced was that the touch panel of the scanner stopped working on a number of occasions. The touch panel is mainly used to adjust the settings for the different scans, such as resolution or whether the scan should be done with color or not. Once these settings are made, the need to use the touch panel is not that big, with the very important exception of starting each new scan. Hence a non-functioning touch screen could be a serious problem. Fortunately, the scanner also provides a more stable button under the touch screen, which can be used just to start scans if you cannot start them otherwise. That saved a lot of time, since the only way to get the touchscreen to work again was to turn the scanner off and let it rest for a couple of hours. To prevent problems with humidity, the scanner bag was equipped with several small bags of silica gel during the entire period in Belize. It is used as a desiccant to control local humidity and may have done some good in keeping the scanner in such a good shape.

All in all it was a very interesting trip and we are really looking forward to have time to work with the data.

Scan of the entrancecave. To the left of the middle you can see two people that happened to be scanned. Good to use as a reference

/Stefan