The word “Digitization” is ubiquitous today. The term is extremely used but its meaning is worn out when taken to a specific terrain. Answering to how?, with what?, for what?, and even, why? for the particular case of Cultural Heritage it is not an easy taks, nor closed. Digitization and Heritage is a Romeo and Juliet style romance (to make a cultural simile), where the respective families view the matter with suspicion, even when it is destined to be a well-matched marriage, not one of convenience.
Digitization sounds technological, state-of-the-art. Heritage sounds archaic, old-fashioned. Putting one together with the other, and avoiding formal definitions (otherwise non-existent), it is proposed to define digitization in this case as the incorporation of digital technologies (those based on electronics, optics, computing and telecommunications) to the products, processes and services that organizations follow and offer for research, protection, conservation, restoration and dissemination of Cultural Heritage.
Digitization affects the way of facing work, the proper way of working and the organization in itself, modifying its structure and managing. This alteration in the organization schema causes an atavistic fear of losing the artisan and professional-knowledge supported value that features the companies in the Cultural Heritage sector, made up of more than 90% by SMEs in the EU. This is the real reason why they take the longest to “digitize”. It is not just an issue about buying, installing and operating computers, software and wireless networks. The change is deeper: it is not a question of appearance; it is a fundamental question. But it is well worth remembering that the workshops and people who appear in history and arts books today because the works they have bequeathed, are indeed famous for having innovated and used the best technologies available on their time.
But, what are the technologies at stake today for the Digitization of Cultural Heritage? Without being exhaustive, and also being aware of leaving things in the pipeline, the most demanded technologies are summarized below:
Multidimensional modelling and simulation (including Heritage BIM -HBIM[1]-): exact 3D virtual replicas of movable and immovable assets; mechanical, electrical, acoustic, lighting and signal coverage simulations with specialized software; 4D (evolution in time). The HBIM parametric modelling is remarkable to complying with Directive 2014/24/ EU and also to addressing extra dimensions: 5D (costs); 6D (sustainability and energy efficiency); 7D (maintenance).
Sensors, Internet of Things (IoT) and 5G: multipurpose devices for capturing, combining and communicating all kinds of data over the Internet. The 5G allows making between 10 and 20 times faster the traffic of these data compared to current 4G mobile communications. These technologies are typically used in structural and environmental monitoring for condition assessment.
Data analytics to get useful information: cloud computing (to archive all kind of information and making it accessible and searchable from anywhere and from any device connected to the Internet); edge computing (local computing -on the axis-, to improve response times and save bandwidth); big data (massive treatment of structured and unstructured data – in the order of Petabytes: 1015 bytes-). The determination of causes and effects, together with the prediction and characterization of behaviours (including visitor flows) are common examples
Artificial intelligence (AI): machine learning (ability to learn without specific coding) and deep learning (learning based on neural networks that mimic the basic functioning of the human brain) are well-known. One example is the Gigapixel technology to enlarge images to see tiny details thanks to intelligent computer processing of extremely high-quality photographs. Another example is the automatic recognition of symbols or animal species in a prehistoric rock engraving on which a-priori nothing can be distinguished.
Systems dynamics and informational entropy: they are ways of studying adaptive mechanisms in complex and changing systems (such as all those that humans forge -which are precisely characterized by creativity and culture-) to make predictive models or to support decision-making and management.
Computer vision: capturing and processing of images by cameras that operate in one or more spectral ranges to see beyond our eyes also at all scales (from space with COPERNICO satellites, to the microscopic world): search for patterns, detection of pests , humidity, alterations, irregularities and falsifications, definition of authorship and artistic techniques, conservation assessment. Applied to video analytics, it is very effective in guaranteeing the security against theft, vandalism or looting.
Digital twins: combining some (or all) of the previous aspects (multidimensional modelling, simulation, computer vision, sensors, IoT and AI) upon a virtual replica ready to remotely work under a multidisciplinary approach, allows to anticipate possible problems and experiment safely before performing any intervention, helping to its optimal planning. It can be applied to movable assets, but it has special significance in immovable ones.
High-quality audio and video: Hi-Res for audio and FullHD, 2K and 4K for video are words already entered in our lives. They allude to the highest attributes and durability of the audio and video formats that can be used for the registration of intangible heritage or the broad dissemination of heritage in general.
Virtual reality (VR), augmented reality (AR) and mixed reality (XR): to recreate spaces, decorations and configurations, past or future, even to look into planned interventions upon 3D models using special glasses or smartphones.
Ontologies and semantics: to uniquely name and hierarchically structure the constituent elements of movable or immovable assets and cultural landscapes so that they are understandable both by specialists and laymen regardless of their language and cultural background.
Interoperability: to synchronize data, systems and processes nevertheless of their origin and format.
Cybersecurity: to defend against malicious attacks on computers, servers, mobile devices, electronic systems, networks and data. Blockchain allows avoiding falsifications as well as guaranteeing the authorship and the digital visa of projects.
Robotization and 3D printing: configurable robots (adaptable, shippable and remotely-assisted) allow the modular construction of specific elements in-situ. They also allow the automation of inspection, cleaning, assembly, conservation and restoration processes in dangerous or hard-to-reach places, quickly and accurately. It can be combined with 3D printing for sealing, insulating and watermarking in different materials and finishes. Particularly 3D printing allots functional replication (total or partial) at different scales to create prototypes, parts, mock-ups and test series.
Nanotechnology and new advanced materials: the continuously increasing processing power of computers and their combination with the hardware of machinery allows the study and manipulation of matter in incredibly small sizes (typically between 1nm and 100nm), resulting in a wide range of materials and techniques usable in conservation and restoration.
In March 2021, the European Commission published a report that reviews and evaluates the actions and progress achieved in the EU in the implementation of the Recommendation (2011/711/EU) on digitization, online accessibility and digital preservation of cultural heritage as one of the main political instruments in those matters[1]. The ecological and digital transitions are, in fact, the keys to the agreement on the so-called Recovery Plan for Europe[2]. EU Member States have agreed on the need to invest more in improving connectivity and related technologies to strengthen the digital transition and emerge stronger from the COVID-19 pandemic, transforming the economy and creating opportunities and jobs for that Europe into which citizens want to live. During the confinement society has shown that Cultural Heritage in digital format was a true social balm, with museums and collections open online 24 hours a day.
Thus it is the right time and there are no general solutions for “digitization”. Cultural Heritage is not about producing thousands of cars, parts or packaging per day. Quite the contrary: each company, each project, each asset must be considered for what it is: something unique. To make a clear example, imagine somebody getting into the supermarket and asking ‘what is there to eat?’ The answer, consonant with the perplexity, could be: there are from precooked to fresh, meat, fish, eggs, dairy and sweets in all possible varieties. It depends on your culinary tastes, your hunger and the time you have, your nutritional needs, the time of day … In short: particular problems require particular solutions.
Public initiatives like ‘Connected Industry 4.0’ are developing measures that allow the industrial fabric to benefit from the intensive use of ICT in all areas of its activity. These initiatives are linked to the term Industry 4.0, which refers to the challenge of carrying out the 4th Industrial Revolution through the transformation of industrial sector by the enabling technologies incorporation: 3D printing, robotization, sensors and embedded systems, augmented reality, artificial vision, predictive maintenance, cybersecurity, traceability, big data, etc.
Construction sector, as the industrial one, is immersed in a deep metamorphosis before the irruption of these new technologies. The economic crisis has been very intense in this market. As a strategy for its recovery, it must its particular revolution, taking full advantage of the opportunities offered by enabling technologies. For this reason, the ‘Construction 4.0’ concept appears as a necessity to digitize the construction through the incorporation of enabling technologies adapted to their particularities.
In this sector, it is the first time that a revolution is built ‘a priori’, which gives us the opportunity both to companies and to research centres to participate actively in the future.
In CARTIF, we work along this line by means of some projects that apply these technologies. In the case of the BIM (Building Information Modeling), which proposes to manage the complete cycle of the project through a digital 3D model, we develop improvements to include all the actor of the value chain.
With reference to 3D printing, a methodology that allows the construction of objects layer by layer, obtaining singular pieces or with complex geometries, CARTIF applies technologies to the direct printing on vertical surfaces for the rehabilitation of facades.
If we talk about robotization, besides the fact that making specific robots to certain tasks, adapt existing machines increasing their autonomy and safety of operators. In this line, we collaborate to develop monitoring and navigation technologies for the automatic guidance of machinery and to detect risks situations between machinery and operators.
With all these innovations, the future of construction is promising, if and when this research would be considered as an essential basis for its growth.
In the European Union 40% of the total final energy is consumed in residential and tertiary buildings. That is reason behind several European Directives established with the aim that the Member States develop long-term strategiesencouraging the renovation of residential and commercial buildings applying specific energy efficiency criteria. In order to define efficient strategies they have to be established in a holistic way; beyond individual buildings and thinking in wider terms of districts and cities. For this reason, several research projects are nowadays exploring the best way to perform retrofitting activities with those results in mind.
Nonetheless, the definition of a retrofitting strategy for any neighbourhood or any city is a trivial issue. There are many factors that must be analysed before proceeding with such intervention. Although the objectives to be achieved are often clear (reduction of energy consumption, reduction of greenhouse gas emissions, including renewable energies, etc.), the method to achieve those objectives is variable and different measures can be applied to the same scenario with varying degrees of success. The analysis of the most effective measures in cost-benefit terms requires of a considerable amount of information about the considered area and carrying out a series of complex calculations that allow to obtain indicators associated with the several possible interventions that may take place.
So it is at this point that the use of ICT (Information and Communication Technologies) adds value: performing calculations through simulation tools (including energy, costs and environmental aspects among others) the analysis of the different scenarios is more accurate and also tedious manual processes prone to failures are automated. However, although different simulation tools are available in the market a single specific tool that fully automates retrofitting interventions just does not exist nowadays.
In this regard, CARTIF is currently working on several projects aimed at creating such tools for designing retrofitting projects in cities such as the new project Nature4Cities or OptEEmAL, started in 2015. Both projects are funded by the European Commission under the Horizon 2020 R&D programme.
Nature4Cities aim is the development of a tool to support design of energy retrofitting projects in urban environments by applying Nature Based Solutions (NBS). This type of solutions has already been covered by my colleagues in a previous post.
On the other hand, OptEEmAL project focuses on developing a design platform for energy retrofitting projects at district level. Working with input data provided by the user (BIM, CityGML and other type of data) the OptEEmAL platform automatically generates and evaluates possible retrofitting scenarios based on implementing a set of measures for energy conservation.
Such measures are contained in a catalogue according to a data model based on standards (such as IFC). The solutions included in this catalogue are both passive (envelope improvements, change of windows) and active (concerning energy generation systems, renewable energies or control strategies) and are applied both at building and district level. These measures may be generic solutions with default values or specific solutions provided by commercial entities.
In order to evaluate the various potential scenarios, a set of performance indicators are analysed and then categorised into different categories: energy, comfort, environmental, economic, social and urban. Once the optimisation has taken place, the OptEEmAL platform shows to the user the solution with better results in terms of indicators. As a result of the process OptEEmAL provides the user with very detailed information on the retrofitting project.
CARTIFwill continue working in this area of knowledge with our strong commitment to support energy efficiency and ultimately improve the cities and places where we live.
In recent years, being the instrumental techniques cheaper and cheaper and the computational algorithms more accesible (even open source) several researchers and consultancy companies are developing new 3D abilities. Laser scanning or photogrammetry techniques are applied to mechanical or structural systems in order to collect some geometric specifications, which may be not available for different reasons.
Although direct engineering process will usually have the technical reports and drawings of the product prior to its building or manufacturing, it is usual that the old factories or buildings are not documented or, if they are, it is quite common that the drawings do not match to project. And even so, the time may have caused differences in the material behavior (chemical attacks, damage, settlements of supports or other common structural pathologies).
Footbridge stadium Balearic (Mallorca, Spain)
Often the collected data are focused on geometric dimensions and surface characteristics such as roughness and color. One of the most obvious applications is the three-dimensional reconstruction of architectonic buildings, either for rehabilitation or development of augmented drawings (BIM) or for historical or industrial heritage.
Being very useful the geometric data collected, in structural engineering it is necessary to add more information about the characteristics of different building materials, the joints between them and their possible interaction with the supports and the ground.
Fortunately, other enabling technologies to extract some additional information are also becoming more widely available. In this post we will see how using simple acceleration records and identification algorithms together with computational model updating techniques can complete the geometric information so that all technical specifications, necessary to estimate the dynamic behavior of the structure under study, can be obtained. These procedures do not require destructive testing and, even though these tests were viable, they did not provide the required information despite their higher cost.
First it should be noted that the geometric data collectedusing 3D techniques, irrespective of dimensional accuracy, refer to a particular state of load on the structure (at least due to the gravitational action) and corresponds to a particular ambient temperature. Both conditions can affect in a significant way when dealing with slender structures such as bridges and pylons. Furthermore these constructs generally experience unavoidable deformations due to environmental actions that can also affect dimensional accuracy of the 3D model.
Second it is interesting to note that in structural engineering and building is usual to use commercial components (proper cross-sections, formworks, pipes, lamps, …) of known discrete dimensions. This enables the possibility of carrying out adaptive scaling for improving the dimensional accuracy or for local refinement. So, it is not necessary comprehensive dimensional records and low cost systems (both instrumental as compact cameras and computer software) can be good enougth.
Considering the above and assuming certain skills for computational modeling, it is posible to create a preliminary model of the structure. On this model, using the finite element method, it is easy to estimate the incremental deformation due to certain loads or thermal actions and through appropriate correlations begin to estimate certain internal parameters (effective density, stiffness, damage, etc.). However, the methodology is especially important when the above information is combined with modal data.
To do this, first thing is to have the experimental eigenmodes (identified through operational modal analysis by post-processing acceleration records under environmental loading) and then select certain parameters of the computational model to be modified. Now it is the turn to adjust the value of these parameters (through optimization routines and depending on the sensitivity of each parameter and its range of reasonable values) to match with the experimental modes to the numerical ones (calculated via FEM). This process should take into account not only the most representative mode shapes but also their modal frequencies and damping.
Once proper values for these parameters are determined, the computer model can be used not only to generate the corresponding technical documentation of the as-built structure but also to estimate their vulnerability to accidental loads, or to evaluate the life-span or to estimate the performance of conservation jobs, among other applications. Those tasks are known as “structural re-engineering”, whose advantages can be matter for other post.
