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Procedure di costruzione della prospettiva nel progetto del disegno
No full textUna metodologia di intervento
Il termine progetto richiama automaticamente alla nostra mente l’idea del disegno di progetto, ovvero
l’insieme di quelle informazioni grafiche inerenti al tipo di intervento che si è stabilito di realizzare in un
manufatto o in un paesaggio, etc. In realtà il progetto di cui si parla è sempre accompagnato dal progetto del
disegno il quale, a sua volta, diventerà disegno di progetto. Il gioco di parole non deve confondere il lettore,
al contrario, deve suscitare in lui la curiosità intellettuale di individuare, laddove realmente esistesse, l’esatto
confine tra progetto del disegno e disegno di progetto. Non è facile stabilire quale dei due viene per primo: a
volte non esiste alcuna correlazione tra i due, altre volte l’idea progettuale, dalla quale nasce il primo
disegno, lo schizzo, e il disegno nella sua complessità e totalità, si influenzano vicendevolmente pervenendo
alla rappresentazione del progetto definitivo. Spesso, tuttavia, l’immagine finale costituisce un compromesso
inaccettabile tra l’idea del suo pensatore e quello che di essa la rappresentazione esprime. Ciò è da
imputare, spesso, ad una mancata progettualità del disegno che penalizza fortemente il ruolo della
comunicazione nella sua completezza; ciò emerge per esempio quando le viste sono aberrate o molto di
scorcio, quando o l’immagine risulta troppo piccola o poco significativa, quando la posizione assunta non
consente il riporto di particolari sufficientemente recepibili, etc...
Possiamo dire, pertanto, che l’idea si esprime attraverso un disegno il quale, a sua volta, dovendo
rispondere a determinati requisiti, necessita di una progettazione che va dalla scelta del metodo di
rappresentazione a quella della scala da adottare -tanto più grande, quanto più piccolo è il denominatore-, al
supporto cartaceo, al tipo di matita o di pennini, alla scelta del colore, etc.
In questo modo si ha la possibilità di condurre il proprio studio con animo sereno, guidato dalla
consapevolezza e dalla certezza di giungere a risultati voluti, senza sgradite sorprese.
Progettare il disegno significa considerare tutti quegli aspetti che intervengono nel linguaggio visivo e
comunicativo dell’immagine, significa esaminare tutti i dati in possesso in modo da perseguire un obiettivo
finale, significa fare delle scelte opportunamente valutate e, prima ancora, significa leggere ed analizzare ciò
che si vuole rappresentare, sia che si tratti di un’idea di progetto sia di un rilievo di un manufatto esistente.
Nel metodo tradizionale della prospettiva si imposta in planimetria un oggetto A, una linea quadro verticale
ad una certa distanza dall’oggetto ed un punto V, posizione dell’osservatore ad una distanza DELTA dal
quadro. Tutto il sistema è considerato a scala. Questo comporta che il campo grafico non è una porzione
reale del quadro reale, bensì una parte del quadro ridotta a quella scala e in questo modo non si riproduce il
sistema prospettico del Brunelleschi. Nel sistema proposto, viceversa, il quadro e la relativa posizione
dell’osservatore sono quelli reali, dell’occhio e del vetro. L’oggetto reale, posto a distanza reale è sostituito
da un modello1 a scala (che è l’unico ad essere ridotto) posizionato a distanza opportuna rispetto al quadro.
La ricerca della posizione del modello sostitutivo della realtà, ai fini di ottenere una rappresentazione identica
a quella che otterremmo con l’oggetto reale a distanza reale -sistema del Brunelleschi- è legata all’altezza
dell’osservatore rispetto al piano geometrale ed alla distanza dell’osservatore dal quadro. Individuati tali
rapporti è possibile rappresentare l’oggetto in posizione planimetrica ribaltata sullo stesso campo a varie
scale secondo le opportunità. Per fare rientrare nel campo le immagini di larghezze ed altezze reali, può
facilmente individuarsi sia la profondità che la scala di tale planimetria e potere ottenere, in tal modo, una
vista prospettica che riempie l’intero campo. Se, da un lato, il metodo esposto aderisce perfettamente alle
ideologie del Brunelleschi, dall’altro lato, consente inoltre il superamento del rilievo prospettico –
1 Il modello a cui si fa riferimento è un artifizio risolutivo per una vista diretta di dimensioni reali. Diverso è il modello che generalmente
sostituisce la realtà nelle proiezioni parallele, laddove le dimensioni reali eccedendo il campo grafico e devono essere sostituite da
dimensioni a scala.
rappresentando soltanto ciò che si vede- con il progetto prospettico -passando così dalla rappresentazione
del reale a quella del virtuale-. Si precisa, ancora, che per realtà virtuale si può anche intendere, la
rappresentazione del reale da una posizione plano-altimetrica fisicamente impossibile, impedita o inefficace.
La ricerca dei parametri di impostazione della rappresentazione può essere sintetizzata come progetto del
disegno
SfM Techniques Applied in Bad Lighting and Reflection Conditions: The Case of a Museum Artwork
No full textIn recent years, SfM techniques have been widely used especially in the field of Cultural Heritage. Some applications, however, remain undefined in cases where the boundary conditions are not suitable for the technique. Examples of this are instances where there are poor lighting conditions and the presence of glass and reflective surfaces. This paper presents a case study where SfM is applied, using a DSLR camera (Nikon D5200), to the “Head of Hades” inside a glass theca and under a large number of light sources at different distances and of different intensities and sizes. The geometric evaluation has been made comparing the DSLR camera model against the 3D data acquired with structured light systems
Image-based 3D reconstruction using traditional and UAV datasets for analysis of road pavement distress
No full textOn local and urban networks, the enduring issue of scarce resources for Maintenance, Rehabilitation, and Reconstruction strategies (MR&R) has led, in many cases, to using unadjusted or poor techniques for road pavement distress detection and analysis, yielding ineffective or even counterproductive results. Therefore, it is necessary to have tools that can carry out quick, reliable and low-cost assessment surveys. This paper aims at validating the use of innovative and low-cost technologies for road pavement analysis, assessing their potentialities for improving the automation and reliability of distress detection. A Structure from Motion (SfM) technique is analyzed at different altitudes. The technique was applied on a distressed road pavement inside the University Campus in Palermo. The models obtained were compared with a terrestrial laser scanned 3D model to analyze the technique's metric accuracy and reliability. The results have shown that the technique accurately replicates pavement distresses, inciting an integrated approach to optimize pavement management strategies
3D RECONSTRUCTION-REVERSE ENGINEERING – DIGITAL FABRICATION OF THE EGYPTIAN PALERMO STONE USING BY SMARTPHONE AND LIGHT STRUCTURED SCANNER
Full text linkThis paper presents a pipeline that has been developed to acquire a shape with particular features both under the geometric and radiometric aspects. In fact, the challenge was to build a 3D model of the black Stone of Palermo, where the oldest Egyptian history was printed with the use of hieroglyphs. The dark colour of the material and the superficiality of the hieroglyphs' groove have made the acquisition process very complex to the point of having to experiment with a pipeline that allows the structured light scanner not to lose the homologous points in the 3D alignment phase. For the texture reconstruction we used a last generation smartphone
UAV experimentation for pavement distresses detection
Full text linkIn recent years, due to the high costs of
traditional road failure detection techniques, the research
has focused its attention on the use of the drone for the
recognition of deterioration by experimenting with lowcost 3D detection techniques. The use of these techniques
allows to carry out monitoring operations according to a
structured and effective planning to guarantee the safety
of users. The purpose of this paper is to verify the
gradient that determines the loss of accuracy of the 3D
acquisition as the flight altitude changes. in this way, the
practitioner will have a handbook through which he can
decide the altitude of the flight to obtain that degree of
metric accuracy. The application is conducted within a
road inside the University campus using the DJ Mavic
pro2 drone
Procedere
Full text linkIn the disciplinary field, the term procedere (from the lat. procedĕre, comp. of pro ‘ahead’ and cedĕre ‘to go’) [Treccani], effectively recalls the action of advancing, of developing, in a temporal sense, in a continuous process, proper of Representation, of decoding, interpre-tation, and analysis of Architecture. The discipline of Drawing is constantly evolving, taking advantage of cultural and technical evolution, technological innovation tools for knowledge and design, forms of organizing thought, and producing the environment. However, the word procedere (develop) also recalls the action of deriving, originating, com-ing, arising, emphasizing that experimental research and new procedural contributions draw lymph from the disciplinary tradition, which, through the language of Drawing – a code that can never be delegated –, plays a basic role. The complementarity and synergy of all the graphic-expressive methods of representation, therefore, constitute an indispensable cultural baggage that enriches the researcher and allows him to manage the instruments of knowledge as well as to govern the geometric properties that regulate space, to be able to read, communicate and divulge Architecture
3D #DigitalInvasions: a crowdsourcing project for mobile user generated content
No full textThis paper introduces the #InvasioniDigitali project which is an online crowdsourcing initiative started in Italy in 2013 with the aim to promote the value of and engagement with local heritage. The paper focuses on two case studies of pilot ‘invasions’ using 3D data capture by students at museums and heritage sites in Sicily
Image-based 3D reconstruction using traditional and mobile-phone data-sets for road pavement distress analysis
No full textThe issue of road networks being in deplorable conditions is one that is widespread globally. One of the main precursors for this is that when preparing maintenance
management systems, many road agencies rely on data which is often outdated or inaccurate. This is due in many cases to insufficient budgets which are unable to
adequately address both maintenance and rehabilitation. It is therefore critical that road agencies have better tools at their disposal to help combat these issues. One of the possible techniques that have been identified is the use of structure from motion techniques to adequately identify road pavement distresses. This paper advances previous work in this area and explores the accuracy of using mobile phones to collect the imagery as opposed to traditional methods relying on professional cameras and equipment. This would provide a lower cost and readily available alternative for practitioners. The techniques have been applied on a distressed pavement in Palermo, Italy using data-sets from a mobile phone and a professional camera to analyse the quality and adequacy of using data-sets from the mobile phone. The results indicate that the mobile phone data-sets can adequately utilize the techniques and therefore this incites the possibility of integrating mobile integrations with the technology specifically focused on pavement management systems
HIGH QUALITY TEXTURE MAPPING PROCESS AIMED AT THE OPTIMIZATION OF 3D STRUCTURED LIGHT MODELS
Full text linkThis article presents the evaluation of a pipeline to develop a high-quality texture mapping implementation which makes it possible to carry out a semantic high-quality 3D textured model. Due to geometric errors such as camera parameters or limited image resolution or varying environmental parameters, the calculation of a surface texture from 2D images could present several color errors. And, sometimes, it needs adjustments to the RGB or lightness information on a defined part of the texture. The texture mapping procedure is composed of mesh parameterization, mesh partitioning, mesh segmentation unwraps, UV map and projection of island, UV layout optimization, mesh packing and mesh baking. The study focuses attention to the mesh partitioning that essentially assigns a weight to each mesh, which reveals a mesh’s weight calculated by considering the flatness and distance of the mesh with respect to a chart. The 3D texture mapping has been developed in Blender and implemented in Python. In this paper we present a flowchart that resumes the procedure which aims to achieve a high-quality mesh and texture 3D model starting from the 3D Spider acquire, integrated with the SfM texture and using the texture mapping to reduce the color errors according to a semantic interpretation
Exploiting Data Analytics and Deep Learning Systems to Support Pavement Maintenance Decisions
Full text linkRoad networks are critical infrastructures within any region and it is imperative to maintain their conditions for safe and effective movement of goods and services. Road Management, therefore, plays a key role to ensure consistent efficient operation. However, significant resources are required to perform necessary maintenance activities to achieve and maintain high levels of service. Pavement maintenance can typically be very expensive and decisions are needed concerning planning and prioritizing interventions. Data are key towards enabling adequate maintenance planning but in many instances, there is limited available information especially in small or under-resourced urban road authorities. This study develops a roadmap to help these authorities by using flexible data analysis and deep learning computational systems to highlight important factors within road networks, which are used to construct models that can help predict future intervention timelines. A case study in Palermo, Italy was successfully developed to demonstrate how the techniques could be applied to perform appropriate feature selection and prediction models based on limited data sources. The workflow provides a pathway towards more effective pavement maintenance management practices using techniques that can be readily adapted based on different environments. This takes another step towards automating these practices within the pavement management system
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