Francesco Buonamici

Making Blind People Autonomous in the Exploration of Tactile Models: A Feasibility Study

Blind people are typically excluded from equal access to the world’s visual culture, thus being often unable to achieve concrete benefits of art education and enjoyment. This is particularly true when dealing with paintings due to their bi-dimensional nature impossible to be explored using the sense of touch. This may be partially overcome by translating paintings into tactile bas-reliefs. However, evidence from recent studies suggests that the mere tactile exploration is often not sufficient to fully understand and enjoy bas-reliefs. The integration of different sensorial stimuli proves to dramatically enrich the haptic exploration. Moreover, granting blind people the possibility of autonomously accessing and enjoying pictorial works of art, is undoubtedly a good strategy to enrich their exploration. Accordingly, the main aim of the present work is to assess the feasibility of a new system consisting of a physical bas-relief, a vision system tracking the blind user’s hands during “exploration” and an audio system providing verbal descriptions. The study, supported by preliminary tests, demonstrates the effectiveness of such an approach capable to transform a frustrating, bewildering and negative experience (i.e. the mere tactile exploration) into one that is liberating, fulfilling, stimulating and fun.

Are We Ready to Build a System for Assisting Blind People in Tactile Exploration of Bas-Reliefs?

Nowadays, the creation of methodologies and tools for facilitating the 3D reproduction of artworks and, contextually, to make their exploration possible and more meaningful for blind users is becoming increasingly relevant in society. Accordingly, the creation of integrated systems including both tactile media (e.g., bas-reliefs) and interfaces capable of providing the users with an experience cognitively comparable to the one originally envisioned by the artist, may be considered the next step for enhancing artworks exploration. In light of this, the present work provides a description of a first-attempt system designed to aid blind people (BP) in the tactile exploration of bas-reliefs. In detail, consistent hardware layout, comprising a hand-tracking system based on Kinect® sensor and an audio device, together with a number of methodologies, algorithms and information related to physical design are proposed. Moreover, according to experimental test on the developed system related to the device position, some design alternatives are suggested so as to discuss pros and cons.

Recent strategies for 3D reconstruction using Reverse Engineering: a bird’s eye view

This paper presents a brief review of recent methods and tools available to designers to perform reverse engineering of CAD models starting from 3D scanned data (mesh/points). Initially, the basic RE framework, shared by the vast majority of techniques, is sketched out. Two main RE strategies are subsequently identified and discussed: automatic approaches and user-guided ones.

Reverse Engineering of Mechanical Parts: a Template-Based Approach

Abstract Template-Based reverse engineering approaches represent a relatively poorly explored strategy in the field of CAD reconstruction from polygonal models. Inspired by recent works suggesting the possibility/opportunity of exploiting a parametric description (i.e. CAD template) of the object to be reconstructed in order to retrieve a meaningful digital representation, a novel reverse engineering approach for the reconstruction of CAD models starting from 3D mesh data is proposed. The reconstruction process is performed relying on a CAD template, whose feature tree and geometric constraints are defined according to the a priori information on the physical object. The CAD template is fitted upon the mesh data, optimizing its dimensional parameters and positioning/orientation by means of a particle swarm optimization algorithm. As a result, a parametric CAD model that perfectly fulfils the imposed geometric relations is produced and a feature tree, defining an associative modelling history, is available to the reverse engineer. The proposed implementation exploits a cooperation between a CAD software package (Siemens NX) and a numerical software environment (MATLAB). Five reconstruction tests, covering both synthetic and real-scanned mesh data, are presented and discussed in the manuscript; the results are finally compared with models generated by state of the art reverse engineering software and key aspects to be addressed in future work are hinted at.

Reverse Engineering of Mechanical Parts: A Brief Overview of Existing Approaches and Possible New Strategies

Reverse Engineering (RE), also known as “CAD reconstruction”, aims at the reconstruction of 3D geometric models of objects/mechanical parts, starting from 3D measured data (points/mesh). In recent years, considerable developments in RE were achieved thanks to both academic and industrial research (e.g. RE software packages). The aim of this work is to provide an overview of state of the art techniques and approaches presented in recent years (considering at the same time tools and methods provided by commercial CAD software and RE systems). In particular, this article focuses on the “constrained fitting” approach, which considers geometrical constraints between the generated surfaces, improving the reconstruction result. On the basis of the overview, possible theoretical principles are drafted with the aim of suggest new strategies to make the CAD reconstruction process more effective in order to obtain more ready/usable CAD models. Finally, a new RE framework is briefly outlined: the proposed approach hypothesizes a tool built within the environment of an existing CAD system and considers the fitting of a custom-built archetypal model, defined with all the a-priori known dimensions and constraints, to the scanned data. INTRODUCTION The introduction of Computer Aided Design (CAD) tools dramatically changed the nature of modern engineering. CAD models, in particular, are currently essential in every engineering aspect and application. In mechanical engineering, specifically, CAD models are key-elements within the entire product development process, from the design phase (e.g. 3D modeling, FE simulations) to the final production (e.g. CAM tools). Given the relevance of CAD models, difficulties and limits come to light when dealing, for instance, with the reengineering of a part whenever its original digital representation is not available. Reverse Engineering (RE) aims at the reconstruction of 3D geometric models of objects and mechanical parts, starting from 3D measured data (points/mesh). This process, also known as “CAD reconstruction”, allows to recover a CAD model of an existing mechanical part/object in order to fulfill all possible designer’ needs. In recent years, considerable developments in RE were achieved thanks to both academic and industrial research (in this second case, mostly relate to RE software packages). Scientific literature is moving towards the development of techniques able to reconstruct CAD models more and more faithful to the original design intent; however, the obtained CAD models are usually not promptly usable by designers for their final needs. This is mainly due to 1) the format of the geometrical description (which usually cannot be directly interpreted by most CAD environments) and 2) imperfections in reconstruction that need to be amended. To better identify these limits and to outline the basis of a new RE strategy to improve the state of the art, a brief review of existing approaches to CAD reconstruction is presented in the following section. Proceedings of the ASME 2016 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference

Reverse engineering modeling methods and tools: a survey

Reverse Engineering (RE) is a long-term goal of engineering and computer science; it aims at the reconstruction of CAD models from measured data by means of 3D mathematical surfaces and geometrical...

Designing the architecture of a preliminary system for assisting tactile exploration of bas-reliefs

The participation of blind people (BP) in cultural life can be improved by enhancing methodologies and tools for facilitating the 3D reproduction of artworks and, at the same time, to facilitate their exploration. The creation of integrated systems including not only tactile media such as, for instance, sculptures or bas-reliefs but even a set of tools capable of providing the users with an experience cognitively comparable to the one originally envisioned by the artist, may undoubtedly enhance artworks exploration. The present work aims to design a conceptual system to aid BP in the tactile exploration of bas-reliefs. This conceptual system comprises both a hand-tracking system and an audio device, together with a number of methodologies, algorithms and information related to physical design. The designed layout, preliminarily tested to understand its potential and limits, proved to be a promising first attempt in enhancing the BP exploration experience.