ROS and professional archaeology

It is a long time since we wrote something in this blog, but (like every year) the excavation season leaves us few time for research. For this reason, today I want to break our silence and show some results of our latest studies regarding archeorobotics (the use and development of robotic devices in archaeology).

If you are a regular reader of ATOR, you probably know that since 2012 we are working on optical sensor to achieve a real-time 3D documentation of archaeological evidences (or any kind of data we need to acquire during our projects). Since we started to work on different kind of drones (UAV, ROV, etc...), we discover the nice universe of ROS (Robot Operating System) and SLAM (Simultaneous Localization And Mapping) algorithms. In this post we summarized our research on this topic, focusing on the use of Kinect. Currently we already used this techniques on professional projects (like large scale surveys or excavations), adapting the system to work with RGB-D devices (in underground environment or during cloudy days) or stereocameras (with direct sun light conditions). For instance we helped our friend Cristian Boscaro of IUAV to test this technology in order to document the tunnels which connect the domes of the Abbay of S. Giustina in Padua. This evening I will post a video which shows a particular use of ROS and Kinect to solve a technical problem we had on the field today. We were working to assist the excavator in doing a trench for a pipeline near the Sanctuary of S. Romedio, in difficult logistic condition. Despite the absence of archaeological evidences, the Superintendence asked us to document the track of the trench, since often what is realize during the execution of this kind of work is different from what is planned in the map. Due to the fact that too few hours were left to accomplish a documentation with GPS and total station and that this strategy would have been pretty tricky (inside the gorge of the river S. Romedio) and not so accurate (for the scattering effect of the wood), we decided to use SLAM to get a real time 3D documentation of the track and later to georeference the result on the LIDAR data which the Autonomous Province of Trento releases freely. The video below shows the final result, which completely satisfies the (high) archaeological tolerance of this project.

That's all for today! Have a nice evening!

The devils boat

This year, thanks to Prof. Tiziano Camagna, we had the opportunity to prove our methodologies during a particular archaeological expedition, focused on the localization and documentation of the "devils boat". 

This strange wreck consists in a small boat built by the Italian soldiers, the "Alpini" of the battalion "Edolo" (nicknamed the "Adamello devils"), during the World War 1, near the mountain hut J. Payer (as reported by the book of Luciano Viazzi "I diavoli dell'Adamello"). 

The mission was a derivation of the project "La foresta sommersa del lago di Tovel: alla scoperta di nuove figure professionali e nuove tecnologie al servizio della ricerca” ("The submerged forest of lake Tovel: discovering new professions and new technologies at the service of scientific research"), a didactic program conceived by Prof. Camagna for the high school Liceo Scientifico B. Russell of Cles (Trentino - Italy).

As already mentioned, the target of the expedition has been the small boat currently lying on the bottom of lake Mandrone (Trentino - Italy), previously localized by Prof. Camagna and later photographed during an exploration in 2004. The lake is located at 2450 meters above see level. For this reason, before involving the students into such a difficult underwater project, a preliminary mission has been accomplished, in order to check the general conditions and perform some basic operations. This first mission was directed by Prof. Camagna and supported by the archaeologists of Arc-Team (Alessandro Bezzi, Luca Bezzi, for underwater documentation, and Rupert Gietl, for GNSS/GPS localization and boat support), by the explorers of the Nautica Mare team (Massimiliano Canossa and Nicola Boninsegna) and by the experts of Witlab (Emanuele Rocco, Andrea Saiani, Simone Nascivera and Daniel Perghem).
The primary target of the first mission (26 and 27 August 2016) has been the localization of the boat, since it was not known the exact place where the wreck was laying. Once the boat has been re-discovered, all the necessary operations to georeference the site have been performed, so that the team of divers could concentrate on the correct archaeological documentation of the boat. Additionally to the objectives mentioned above, the mission has been an occasion to test for the first time on a real operating scenario the ArcheoROV, the Open hardware ROV which has been developed by Arc-Team and WitLab.
Target 1 has been achieved in a fast and easy way during the second day of  mission (the first day was dedicated to the divers acclimation at 2450 meters a.s.l.), since the weather and environmental conditions were particularly good, so that the boat was visible from the lake shore. Target 2 has been reached positioning the GPS base station on a referenced point of the "Comitato Glaciologico Trentino" ("Galciological Committee of Trentino") and using the rover with an inflatable kayak to register some Control Points on the surface of the lake, connected through a reel with strategical points on the wreck. Target 3 has been completed collecting pictures for a post-mission 3D reconstruction through simple SfM techniques (already applied in underwater archaeology). The open source software used in post-processing are PPT and openMVG (for 3D reconstruction), MeshLab and CloudCompare (for mesh editing), MicMac (for the orthophoto) and QGIS (for archaeological drawing), all of them running on the (still) experimental new version of ArcheOS (Hypatia). Unlike what has been done in other projects, this time we preferred to recover original colours form underwater photos (to help SfM software in 3D reconstruction), using a series of command of the open source software suite Image Magick (soon I'll writ  a post about this operation). Once completed the primary targets, the spared time of the first expedition has been dedicated to secondary objectives: teting the ArcheoROV (as mentioned before) with positive feedbacks, and the 3D documentation of the landscape surrounding the lake (to improve the free LIDAR model of the area).
What could not be foreseen for the first mission was serendipity: before emerging from the lake, the divers of Nautica Mare team (Nicola Boninsegna and Massimiliano Canossa) found a tree on the bottom of the lake. From an archaeological point of view it has been soon clear that this could be an import discovery, as the surrounding landscape (periglacial grasslands) was without wood (which is almost 200 meters below). The technicians of Arc-Team geolocated the trunk with the GPS, in order to perform a sampling during the second mission.
For this reason, the second mission changed its priority an has been focused on the recovering of core samples by drilling the submerged tree. Further analysis (performed by Mauro Bernabei, CNR-ivalsa) demonstrated that the tree was a Pinus cembra L. with the last ring dated back to 2931 B.C. (4947 years old). Nevertheless, the expedition has maintained its educational purpose, teaching the students of the Liceo Russell the basics of underwater archaeology and performing with them some test on a low-cost sonar, in order to map part of the lake bottom.
All the operations performed during the two underwater missions are summarized in the slides below, which come from the lesson I gave to the student in order to complete our didactic task at the Liceo B. Russell.

Aknowledgements

Prof. Tiziano Camagna (Liceo Scientifico B. Russell), for organizing the missions

Massimiliano Canossa and Nicola Boninsegna (Nautica Mare Team), for the professional support and for discovering the tree

Mauro Bernabei and the CNR-ivalsa, for analizing and dating the wood samples

The Galazzini family (tenants of the refuge “Città di Trento”), for the logistic support

The wildlife park “Adamello-Brenta” and the Department for Cultural Heritage of Trento (Office of Archaeological Heritage) for close cooperation

Last but not least, Dott. Stefano Agosti, Prof. Giovanni Widmann and the students of Liceo B. Russel: Borghesi daniele, Torresani Isabel, Corazzolla Gianluca, Marinolli Davide, Gervasi Federico, Panizza Anna, Calliari Matteo, Gasperi Massimo, Slanzi Marco, Crotti Leonardo, Pontara Nicola, Stanchina Riccardo

Soil triangle integration in a PostgreSQL based system for archaeological recording sheets

This is the second presentation we gave at ArcheoFOSS 2016. This time the topic is more related with geoarchaeology and regards geTTexture (the open source application we developed in order to speed up the sedimentation est).

Here below is the link to the original presentation, for the reader who wants to see it directly online:

www.museidironzone.it/openLibrary/html/gettexture/gettexture.html

For those who prefer to see it on youtube, I just uploaded it on our channel:

Like for last post, I report here below a short abstract, describing shortly each slide of the presentation:

SLIDE 1

Title and overview

SLIDE 2

Compiling the archaeological recording sheet is one of the most time-expensive operation during an archaeological project both doing it manually...

SLIDE 3

... or using a database.

SLIDE 4

Considering the Italian standards (ICCD, "Istituto Centrale per il Catalogo e la Documentazione"), often new archaeologists have difficulties in describing the composition of the archaeological layer.

SLIDE 5 and 6

SLIDE 7 and 8

No particular difficulties are detected in describing the artificial elements.

SLIDE 9 and 10

A little bit more complicated is considered to describe the organic and oranogenic elements.

SLIDE 11 and 12

The most difficult field is considered the geological one.

SLIDE 13

Geological materials are splitted into two categories: skeleton and fine earth

SLIDE 14 and 15

The skeleton is normally simpler to identify (both in the field and in the lab).

SLIDE 16 and 17

The fine earth is maybe the most complicated archaeological element to identify on the field, while specialist (geoarchaeologists) need to use specific equipement in the lab.

SLIDE 18

Fine earth definition on the field is foten carried on with anametric and sobjective methodology.

SLIDE 19

Like feel, ball and ribbon test

SLIDE 20

The sedimentation test gives more objective results with a minimum metric value.

SLIDE 21

Arc-Team used validated the use of sedimentation test also in emergency excavation (which have a stricter time-table respect other archaeological projects)

SLIDE 22

Thank to +Mattia Segata  (Arc-Team's geoarchaeologist at ATLAB), the basic methodology has been improved considering the Strokes' Law.

SLIDE 23

+Giuseppe Naponiello  (Arc-Team DataBase and WebGIS expert) improved a PostreSQL dabatase, developed on the Italian archaeological recording sheet. The Database is able to integrate the data coming from the sedimentation test.

SLIDE 24

Future integration are planned for basic analytical chemistry analyses on the field.

SLIDE 25

And for more specific laboratory analyses (e.g. Energy Disperive X-ray Spectrometry).

SLIDE 26

The DataBase can be easily integrated into a WebGIS

SLIDE 27

The slides is just a demonstration of the software (the code is taken from a prototype).

SLIDE 28

The slide is just an example of one of the videotutorial Arc-Team is producing to explain the sedimentation test and the use of geTTexture.

SLIDE 29

geTTexture will be one of the open source application for archaeology which Arc-Team is developing and that will compose the suite Arc-Tool.

SLIDE 30

Another extension of geTTexture Arc-Team is working on is related with colorimetry. The idea is to integrate a tool to record anametric analyses

SLIDE 31

or metric data coming from Open Hardware devices (e.g. Public Lab spectrometer)

SLIDE 32

Thak you for your attention

Have a nice day!

QGIS - Reshape Features

This short Videotutorial shows you the effect of QGIS "Reshape Features" tool on vector lines.
If you have time to clean and smooth vector-lines manually, you can try that possibility.

If you want to keep up always with our latest videos, 

just subscribe our 

You Tube-Chanel:

   

OpenJUMP GIS: from a local (cartesyan) system to a projeced coordinate system

Sometimes we are asked why (after 11 years) we still keep OpenJUMP in ArcheOS, since QGIS became such a functional GIS  and could cover all the feature of the other similar software. The main reason for such a choice are two:

1. QGIS developed very fast and can happen that some tools are still buggy when released (like for the newest georeferencer version)

2. the software (Polygontool) our friend +Szabolcs Köllö (aka Keulemaster) developed for us, in order to handle big data in archaeological surveys, is strictly connected with OpenJUMP

The GIS OpenJUMP

Today I just finished to package for (ArcheOS Hypatia) the last version of this GIS (OpenJUMP 1.9.1) and to upload it in our experimental repository (soon we share it), so I prepared a new videotutorial to illustrate one of the operation in which OpenJUMP is still useful, since the similar tool of QGIS are sometimes buggy: the recovering of old excavation data from a local (cartesian) coordinate system to a projected coordinate system (e.g. in the videotutorial, ETRS89 / UTM zone 32 N).

I hope this can be useful. Have a nice day!

Nexus 3 videotutorial

In order to help people in testing Nexus package for ArcheOS Hypatia (see the related post), I just recorded a fast videotutorial to show how this simple tool works.

Please note that the videotutorial refers to ArcheOS Hypatia's package, where Nexus binaries are stored in /usr/bin (so that they can be start from any path in the terminal). If you compiled your Nexus version somewhere in your home folder, than probably you will have to activate the binary from that directory.

Here below is the short video; I hope it will be useful.

Soon I will upload also the new 3DHOP package for ArcheOS Hypatia, with some instruction about it.

Have a nice day! 

ArcheOS Hypatia Nexus package (call for testing)

Hi all,

Since we are working on a project related with a 3D gallery of WW1 remains, we are using the 3DHOP application (which has been also suggested by Nicola Schiavotiello in the ArcheOS-dev Mailing List), developed by the Visual Computing Lab of the CNR-ISTI (Pisa - Italy). In order to exploit the full potential of this software it is useful to use the tool Nexus (see the related issue in ArcheOS github) , to create batched multiresolution mesh structures (to enable Level of Details  - LoD - visualization). 

An example of simple visualization in 3DHOP

For this reason, today I took the occasion to build a simple binary package (for amd64), to be tested for ArcheOS. If someone wants to help in testing the package, it can be downloaded here. Please report in the comment of this post your feedbacks. 

Thank you all!

LAST UPDATED 2016-01-29

In order to implement the two new packages in ArcheOS Hypatia in a short time, we changed the architecture field of the control file of 3DHOP deb package to let it work with all the machines, while we compiled a new i386 package for Nexus. If you want to test the new packages, here are the new files:

3DHOP (architecture all)

Nexus (architecture i386)
Nexus (architecture amd64)

Soon we will update archeos-meta in order to implement these two software.

Any help in packaging is much appreciated!

ArcheOS new issue on GitHub repository (how to)

In order to simplify reports regarding ArcheOS from the community, I just uploaded on YouTube a short videotutorial which shows how to register a new issue on our main repository on GitHub.

Here is the video:

I am sorry for the low quality, but I think you can understand the single steps. Next time I will try to do it better :).

Have a nice day!

ArcheOS-next (new release) codename

Since we started again in developing ArcheOS, we will soon need a new name for the next release (it is important also to maintain a certain continuity with what has been done for ArcheOS Theodoric).

For this new version we would like to have the name of a woman, as until now we just chose male historical figures (it should be a sort of tribute to all our female colleagues around the world).

If you want to participate in choosing the next codename for ArcheOS, just send us your ideas using one of our traditional channels (FaceBook, the development Mailing List, or ATOR itself, commenting this post). We will collect the names during this week and later we will set up a poll to choose the winner, like we did last time. 

The "candidates" should be female notable and historical figures, better if somehow in continuity with the old codenames we used (Akhenaton, Sargon, Xenophon, Caesar and Theodoric).

We are waiting for your proposal. Thank you very much!

The Halicarnassus relief with two "gladiatrices", thefemale counterpart of gladiators
(image from Wikipedia released under Public Domain by the user RsAzevedo)

ArcheOS at Linux Day 2015

"Saturday, October 24 returns the main Italian event dedicated to GNU/Linux, free software, open culture and sharing: dozens of events all over Italy, hundreds of volunteers and thousands of visitors will be involved  to celebrate digital freedom!"

This incipit comes from the official website of the event and summarizes what the Linux Day has been until now. As this year there will be also an event regarding ArcheOS (presented by +Leonardo Zampi  in the city of Florence, at the organization Libera Informatica), I took the occasion to write a post with some links regarding the archaeological GNU/Linux distro, so that this material will be available for anyone who would like to show also this particular branch of the FLOSS universe.

Let's start form the official website, which has been completely renovated by +Fabrizio Furnari and +Romain Janvier, accessible at this address: http://www.archeos.eu/

The main website

As you can read there, we have two mailing list: one for the users and the other for developers.

If you are familiar with it, you can also contact us on our IRC Channel at FreeNode (#archeos).

For those people who would like to work on the code, we use GitHub to develop the main system as well as all the related software projects (source packages, patches, small applications, GUI, etc...).

Finally (for the users), thanks to the collaboration of the University of Innsbruck (Near East and Ancient History Department), we have a wiki system in which we are slowly uploading tutorial and videotutorial. The website is available at this address: http://vai.uibk.ac.at/dadp/doku.php?id=start, but currently is under migration on a new server and will be not accessible for the next couple of weeks. I will keep this post update about the progress of this operation as soon as I will have news.

In the next days I hope to find the time collect more material regarding ArcheOS and to write a post about articles and presentations of the last years. Stay tuned!

Project Tovel part 1: open geodata

As many of you know, since some years we (Arc-Team) are supporting Prof. Tiziano Camgna's project regarding the underwater forest of Lake Tovel (1, 2) in Trentino (Italy).
In the past days we are asked to give a lesson about our contribution to the project at the Liceo Scientifico Bertrand Russel of Cles (TN, Italy). In order to prepare some data for the event, I started to work on a 3D map of the underwater surface of the lake and,  to collect material for different ArcheOS videotutorials I recorded almost the complete process. For this reason I start today a series of "minipost" to publish this material, hoping that this will be useful for some readers.
In this first minipost I will write about open geodata, which are very important for archaeologists, but also for other professionals. Before to enter the topic, I have to say that we live and work (fortunately for us) in a Italian province (Trentino) which is sensible to this matter (open data). If you can understand Italian, you should read +Maurizio Napolitano's blog, one of the real expert in this field currently working at the Fondazione Bruno Kessler.
During the Project Tovel I needed geographical open data to set up the GIS system with some basic cartography. More specifically I started with the "Carta Tecnica Provinciale" (a technical map of the province), which I downloaded form the "Portale Cartografico Trentino" of the S.I.A.T. (Sistema Informativo Ambientale e Territoriale of the Province Trentino). As you can read in the portal (sorry, just Italian), the C.T.P. (Carta Tecnica Provinciale) is available Under the Creative Commons Attribution 2.5 terms.
The videotutorial you can see below just show the simple process to access and download these data (in raster or vector) form the webgis service.

I hope this first post was youseful for some of you, have a nice day!

QGIS: exporting 3D data in threejs

Hi all,

I go on recording small videotutorial regarding the software in ArcheOS 5 (codename Theodoric), trying to collecting more material for the official documentation.

In order to avoid the creation of "wasted food" (videotutorial which are not connected with a real project risk to be useless because too theoretical and too few practical), I am collecting examples from our (Arc-Team) work.

This time I will show how to export 3D data from QGIS and visualize them in a browser thanks to the nice plugin "Qgis2threejs". I I had the necessity to do this kind of operation just to create some screenshot to complete this very simple illustration that gives a geological overview of the working area:

Of course this is not the only way to collect 3D views (I could do the same in GRASS with Nviz), but this workflow is very fast, for a small project.

Here is the videotutorial (I hope it will be useful):

As ususal, the video is uploaded also in our Digital Archaeological Documentation Project.

Have a nice day!

WebRTIViewer

Hi all,

I write this post to complete the one +Rupert Gietl did regarding Large Scale Reflectance Transformation Imaging. As you read in that article, Rupert, using +GRASS GIS, re-built virtually the necessary light conditions to process an RTI image of an entire archaeological area. 

This is just one of the test we are carrying on with RTI techniques, since we are trying to evaluate this methodology under different aspects. Obviously, during our experiments, we encounter interesting researches carried on by other institutions. 

This post regards one of the projects we found on our way (I will write soon about other related works) and, more precisely, a software to share RTI images through internet: WebRTIViewer. Actually the source code of the application, an HTML5-WebGL viewer, is release under the therms of the General Public License 3 (GPL 3) on the website of its author: +Gianpaolo Palma.

Here is an example of its application, using Rupert's data of the archaeological site (better visualized here). To see it, just turno on the light and, holding the left button, move your mouse around.

The software comes with two binary tools (one for Windows 32 bit and the other for Windows 64 bit), which are necessary to prepare the RTI images for the viewer. For this reason I wrote to Giampolo Palma to ask if there would be the possibility to insert WebRTIViewer and the other applications in ArcheOS (to do this we would need the access to the source code of the binary tools, called webGLRTIMaker) and he kindly answered that he likes the idea and he would agree, but before to release the code of the webGLRTIMaker under an open license he will ask the opinion of his labs colleagues (the Visual Computing Lab). This institute, part of the Italian CNR-ISTI, is the same that develops other nice Free/Libre and Open Source (FLOSS) software, usefull in archaeology, such as MeshLab, which is often in our post, or 3DHOP (soon a post about it). Hopefully, if everything goes well, we will have another nice tool to add to the ArcheOS software selection, helping Cultural Heritage professionals in sharing data through RTI technologies.

Here below you can see again webRTIViewer in action (better visualized here), this time with data coming from the archaeological excavation of Khovle Gora (in Georgia), where we work for the University of Innsbruck (Austria) and support technically the fieldwork directed by Dr. Walter Kuntner of the Institut für Alte Geschichte und Altorientalistik.

Digital Archaeology at Lund University

This year, as usual since 2011, +Alessandro Bezzi and me taught some lessons during the course "Archaeology and Ancient History: Digital Archaeology, GIS in Archaeology" at Lund University, held by +nicolò dell'unto. We used the opportunity to update the presentation with which we always start the first lecture. Here below you can see its last version, done with impress.js (just click on the first slide and us the spacebar to navigate).

For a better view, click here

The main topic is digital archeology (or "computational archeology", as it is also known in Italy). 

Initially we define five main operations that are common to any archaeological project: data acquisition, processing, management, analysis and sharing. The first three steps refer to the documentation work-flow, while the last three actions are related with the real research process (of course data management is in common with both of the phases).

Thereafter we analyze each step, starting with data acquisition, which is mainly based on hardware devices. During this operation are normally registered two elements, points and pictures, in order to virtually recover what the archaeological excavation is destroying. With points and pictures it is possible to document objects (artifacts and ecofacts) and actions (basically the archaeological samplings), and their elaboration or, in some cases combination, allows the researchers to record lines, polygon, 3d surfaces and real volumes, to register also the most complex elements of the archaeological record (layers, structures, etc...).

On the contrary of what happen with data acquisition, data processing is mainly based on software. Nowadays it can be divided into two orders of operations: standard procedures (raw coordinates elaboration, 2D photomapping, 2D vector archaeological drawing) and advanced techniques (3D restitution, volume calculation and 3D modeling). The very first and basic step to visualize recorded data is to elaborate the raw coordinates, registered with a total station or a RTK GPS, into a GIS readable code (e.g. CVS or WTK). Combining points and pictures is also possible to create georeferenced photomosaic, using a photomapping techniques (e.g. the metodo Aramus, the Khovle method or the newest Corte Inferiore method). Once obtained a complete georeferenced photomosaic it is possible to use a GIS to draw over the raster level, using one or more vector layers and to connect them with a database. Advanced techniques of documentation are more directly related with 3D and can be based on different methodology to extract morphological, topological and metric informations from one or more pictures (e.g. SvR, SfM, IBM, 3D photogrammetry, etc...). With these informations it is possible to calculate the real volumes of the elements of the archaeological records and use this data to reconstruct the depositional and post-depositional processes, using, when necessary, 3D modeling. Normally, during the different work-flows that can be involved in data processing, many kind of informations are elaborated with raster, vector and voxel graphic in 2 (x,y), 3 (x,y,z) or 4 (x,y,z,t) dimensions. The final aim is to set up a system which is able to handle such a variety of data and this system is the GIS.
In fact GIS software, combined with DBMS, are extremely useful during the data management phase, exactly for their capacity to handle different kind of informations (as many as are the disciplines or sciences which help archeology in its task). The use of such instruments helps to optimize the research, especially in comparison with the traditional techniques, not only during data management, but also during the more delicate stage of data analysis (when most of the cognitive processes are involved).
Among other things, in this fourth step, it is more evident the importance of using open source software and tools to maintain a continuous control on every single process of a study that can lead to the elaboration of new theories. Of course, not all the the analysis are equally sensitive under this aspect: for the simplest researches (anastylosis, building techniques, basic geomorphology, etc...) it is not strictly mandatory to know the source code of the applications, also because in these cases the main examinations are done directly by humans. On the other hand, for more complex studies (landscape archeology and Cost Surface Analysis, statistics, advanced geomorphology, etc...), it is very important to have a complete access to  the formulas and algorithms used by the software in order to keep an human control and do not completely delegate to the computer, among difficult quantitative calculations, also more delicate qualitative investigations (in which the human operator is still essential). In this way it is possible to correctly study all the different informations collected during the archaeological research, considering, at the same time, future integrations (GIS is an open system under a temporal point of view). The last goal of data analysis is to share results with the (scientific and non) community, which is the best way to improve the archaeological discipline itself, especially exploiting the potential of internet.
This lead us to the final step of an archaeological project (data sharing), which can follow different channels, like traditional publication, e-publication (e.g. webgis), exhibitions, etc... The most important thing, at least for scientific disclosure, is to grant a public access to all the informations used for the study (not only the filtered data, but also the raw data), in order to propose new hypothesis and (at the same time) give the all the necessary elements to verify them (no dogma, no authority principle).
To summarize the meaning of this contribution, considering archeology as a science (empiric approach) and a humanity (speculative approach), we can see how computational archeology helps to improve the scientific (empiric) approach, which is often underestimated, granting a more objective data acquisition and processing respects traditional techniques, especially during the critical phase of the archaeological excavation. In fact, unlike scientific experiments, the archaeological excavation is unrepeatable, being the most destructive approach of the discipline (and, at the same time, the most important).

PS

All the screenshots were done with ArcheOS. Some of them are related with really old projects, slowly we will replace them with more updated images...

QuantumGIS and OpenJump: Photomapping with more pictures (Corte Inferiore method)

Hi all,
i would like to share a new method to realize georeferenced 2D-photomosaic. Thanks to the new version of OpenJump (r3856), now it is possible to export the GIS-view to any kind of resolution (no more block to 3800 width-pixel). Just set in the oj_linux.sh file (OpenJump bin folder) the allowed memory in the line 24

JAVA_MAXMEM=${JAVA_MAXMEM--Xmx2048M}

with 2048M my computer can export GIS-view till the value of 6905 width-pixel. More memory gives more resolution.

This is the videotutorial:

and this an example:

Aerial archaeology with FLOS Hardware and Software

Hi all,

today I post an old presentation which I had no time to publish before. Its title is " Aerial archeology with FLOS Hardware and Software" and it is related with a lesson I gave during the Italian Virtual Heritage School 2013, held in Pisa at the headquarters of CNR. 

In my speech I tried to summarize Arc-Team's experience in aerial archeology from 2006 until July 2013. For this reason the slides are a little bit outdated, but the presentation still contains valuable informations for people who want to start with aerial related documentations with free and open source tools.

The first section of the slides is dedicated to an introduction about the two main component of our  Free and Open Source Remote Sensing Platform: ArcheOS (software) and an open source UAV (there are many option, like the UAVP, the ArduCopter, or the KK derivated copters).

The second part of the presentation shows the prototypes we built, both open source (UAV and KKcopter) and commercial (DJ Naza).

In the third branch I tried to summarize in a kind of "blueprint" animated infographic the main structure of a quadcopter. And later I simply repeated the post of ATOR in which Alessandro Bezzi described how to build an open source xcopter (KK board based).

In the fifth section are shown some possible quadcopters configurations, while in the sixth part is analyzed the evolution of the flight techniques (also considering different conditions that can influence the work).

Finally I presented some cases of study and, at the and, are just some tips based on our experience.

The presentation is embedded here below (just click on the window and press space to navigate). As usual in ATOR, it is released with CC BY, so if you need (also just some part of it), you can reuse the material in your work. I hope it can be useful.

For a better view, click here 

2016-04-26 Update

Thanks to self-archiving I can now add the bibliography related with this post:

 ResearchGate: Article

Academia: Article

I hope it will be useful, even if no more up to date it can be a starting point to work in Aerial Archeology with Open Software and Hardware.

From drone-aerial pictures to DEM and ORTHOPHOTO: the case of Caldonazzo's castle

Hi all,
I would like to present the results we obtain in the Caldonazzo's castle project. Caldonazzo is a touristic village in Trentino (North Italy), famous for its lake and its mountains. Few people know about the medieval castle (XII-XIII century) whose tower is actually the arms of the town. Since 2006, the ruins are subject to a valorization project by the Soprintendenza Archeologica di Trento (dott.ssa Nicoletta Pisu). As Arc-Team we participated in the project with archaeological field work, historical study, digital documentation (SFM/IBM) and 3D modeling.
In this first post i will speak about the 3D documentation, the aerial photography campaign and the data elaboration.

1) The 3D documentation 

One of the final aims of the project will be the virtual reconstruction of the castle. To achieve that goal we need (as starting point) an accurate 3D model of the ruins and a DEM of the hill. The first model was realized in just two days of field-work and four days of computer-work (most of the time without a direct contribution of the human operator). The castle's walls were documented using Computer Vision (Structure from Motion and Image-Based Modeling); we use Pyhon Photogrammetry Toolbox to elaborate 350 pictures (Nikon D5000) divided in 12 groups (external walls, tower-inside, tower-outside, palace walls, fireplace, ...).

The different point clouds were rectified thanks to some ground control point. Using a Trimble 5700 GPS the GCPs were connected to the Universal Transverse Mercator coordinate system. The rectification process was lead by GRASS GIS using the Ply Importer Add-on.

To avoid some problems encountered using universal coordinate system in mesh editing software, we preferred, in this first step, to work just with only three numbers before the dot.

2) The aerial photography campaign 

After walls documentation we started a new campaign to acquire the data needed for modeling the surface of the hill (DEM) where the ruins lie. The best solution to take zenithal pictures was to pilot an electric drone equipped whit a video platform. Thank to Walter Gilli, an expert pilot and builder of aerial vehicles, we had the possibility to use two DIY drones (an hexacopter and a xcopter) mounting Naza DJI technology (Naza-M V2 control platform).

Both the drones had a video platform. The hexacopter mount a Sony Nex-7; the xcopter a GoPro HD Hero3. The table below shows the differences between the two cameras.

As you can see the Sony Nex-7 was the best choice: it has a big sensor size, an high image resolution and a perfect focal lenght (16mm digital = 24 mm compare to a 35mm film). The unique disadvantage is the greater weight and dimension than the GoPro, that's why we mounted the Sony on an hexacopter (more propellers = more lifting capability). The main problem of the GoPro is the ultra-wide-angle of the lens that distorts the reality in the border of the pictures.
The flight plan (image below) allowed to take zenithal pictures of the entire surface of the hill (one day of field-work).

The best 48 images were processed by Python Photogrammetry Toolbox (one day of computer-work). The image below shows the camera position in the upper part, the point cloud, the mesh and the texture in the lower part.

At first the point cloud of the hill was rectified to the same local coordinate system of the walls' point cloud. The gaps of the zenithal view were filled by the point clouds realized on the ground (image below).

After the data acquisition and data elaboration phases, we sent the final 3D model to Cicero Moraes to start the virtual reconstruction phase.


3) The Orthophoto

The orthophoto was realized using the texture of the SFM's 3D model. We exported out from MeshLab an high quality orthogonal image of the top view which we just rectified using the Georeferencer plugin of QuantumGIS.
As experiment we tried also to rectified an original picture using the same method and the same GCPs. The image below shows the difference between the two images. As you can see the orthophoto matches very well with the data of the GPS (red lines and red crosses), while the original picture has some discrepancies in the left part (the area most far away from the drone position, which was zenithal on the tower's ruin).

4) The DEM

The DEM was realized importing (and rectifying) the point cloud of the hill inside GRASS 7.0svn using the Ply Importer Add-on. The text file containing the transformation's info was built using the relatives coordinates extracted from Cloud Compare (Point list picking tool) and the UTM coordinates of the GPS' GCPs.

After data importing, we use the v.surf.rst command (Regularized spline tension) to transform the point cloud into a surface (DEM). The images below show the final result in 2D and 3D visualization.

Finally we imported the orthophoto into GRASS.

That's all.

OpenJUMP: adding a vector layer with a customized db

Hi all,

today I recorder a fast videotutorial regarding the GIS OpenJUMP (which is one of the Geographic software integrated in ArcheOS).

Normally, when you add a new vector layer in your project, you get a new empty level, without any database schema, so that you can start to draw your feature, but, if you want to add some info, you have to manually describe your db schema, like in the video below:

Of course, if you have to draw many different layers with a common database schema (like always happen in a normal archelogical GIS), this operation can be time-consuming (and boring). For this reason in the videotutorial below I try to show how to write a short script which automatically add in OpenJUMP a new vector layer with a customized database schema:

Since I fear the quality of the video is too poor in Youtube, I prepared an image in which you can see better the source code of the script:

The code of the script

To work correctly, the script has to be placed in your OpenJUMP folder, in /lib/ext/BeanTools/ and, as you see in the video, you have to refresh the menu in OpenJUMP (Customize --> BeanTools --> RefreshScriptMenu) to find it (in ArccheOS Caesar you will find the script already in the menu. Just modify the code according to your needs).

Like always I added the tutorial in our ArcheOS wiki (DADP project), in order to go on in composing a free documentation system for Digital Archaeology: 

• Tutorial 1
• Tutorial 2

I also uploaded the code of the script into a specific github repository, so that, if you want, you can contribute in its development. We can use the comment space of this post for the discussion about the schema and about its possible modifications (or you can simply download the script and modify it in order to fulfill your specific needs).

I hope it was useful, have a nice day!

File conversion with TOPS (Total Open Station)

HI all,

today I had to convert some raw total station data from Trimble file format (.are) into something simpler and more readable, like a csv file (Comma Separated Value), in order to further process my points and load them inside a GIS. To perform this operation I used a specific software which you can find in ArcheOS: Total Open Station. 

This tool is developed by +Stefano Costa and Luca Bianconi. Here you can find the official website.
I record a short videotutorial about the file conversion. You can see it in the video below.

As usual, I uploaded it also in the Digital Archaeological Documentation Project of Innsbruck University. Here is the direct link.
I hope it will be useful.
Have a nice day!

OpenJUMP: query to extract single points from a general vector layer

Hi all,

today I am working on data elaboration of an archaeological excavation. I decided to record a short videotutorial to show how to perform a very simple query in OpenJUMP (which is a topic I am often asked to explain during lessons about archeology and open source). Before to start, I'll write a short introduction regarding the processing of this data, just to understand why I need to perform this kind of query. 

I worked on this excavations collecting all the data in a local system (with simple 3D Cartesian coordinates), because the job was an emergency archeology project and I did not have the time to set up a geographic coordinate system on the field, before the construction site began. Just at the and of the excavation, I could come with a RTK GPS, to collect some Ground Control Points (GCP) in UTM WGS84. This is the reason why in this time, when I am processing the data, I had to put together all the daily total station downloads in a single cvs file, which I georeferenced in OpenJUMP, using the GCP I collected with the GPS. The problem is that now I will have to separate again the single points, grouping them according to their function (e.g. points for photomapping of area 1, height points of the same area, points for SfM georeferencing, find-points and so on...). To do this operation, I will simply use OpenJUMp (where I loaded and georeferenced the csv file), performing a query on the attribute (the name) of cumulative vector layer , which will tell me where are the the points I need. In this way I can select in the GIS the features I am looking for and put them in a new vector level, copying the db schema of the cumulative layer (name, y, x, z, code). At the end of the process, I will have single separated vector files which I will use in the next steps of data processing (photomapping, 3D, ecc...).

Here is the videotutorial I uploaded in the ArcheOS tutorila wiki (rom Insbruck University):

I hope it was useful, have a nice day!