Multi-objective optimization and rapid prototyping for jewelry industry: methodologies and case studies

Francesca Bertacchini¹, Eleonora Bilotta², Francesco Demarco², Pietro Pantano², Carmelo Scuro²

^{1 Department of Mechanical, Energy and Management Engineering, University of Calabria, Rende, Italy}

^{2 Department of Physics, University of Calabria, Rende, Italy}

Fig. 1 A schematic representation of the adopted logic

The new research and technologies that have ensured the digitalization of industries and the introduction of smart manufacturing are still characterized by poorly studied processes. In particular, communication and integration between different platforms, which form the ecosystem of smart manufacturing, are subject to various communication problems.

The research conducted and propounded in this article is based on the implementation of an integrated manufacturing system that involves parametric modeling, optimization, and additive manufacturing. The ecosystem analyzed guarantees communication between IT platforms such as Rhino-Grasshopper, for parametric modeling, and PreForm, slicing software for Formlab’s stereolithographic 3D printers.

For this purpose, C# scripts have been implemented in order to solve optimization problems in 3D modeling of objects and to guarantee integration between the two platforms. The latter script is configured as a real add-in for Rhino whose advantages are easily demonstrated thanks to the large number of recursive operations that are automated.

Fig. 2 Integration process

Industry 4.0 is a way in the academic and research world to call and identify the fourth industrial revolution that is happening today. This industrial revolution, and the consequent digitalization of the industry, is based on nine pillars including Internet of Things (IoT), big data, cloud, system integration, augmented reality, cyber security, autonomous robot simulation, and additive manufacturing (AM).

In this specific field, it often refers to Industry 4.0 related to production integrated with computer systems the term smart manufacturing (SM). It allows the industry to incorporate the entire product life cycle within the production chain while simultaneously changing the worker’s activities and object design.

Fig. 4 Visual scripting Lissajous Pareto optimal set

This abovementioned concept is typical of another pillar of Industry 4.0, the possibility of guaranteeing the simulation of the finished object before it is made. Industry 4.0 is based on the opportunity to use digital technologies in order to analyze data in real time, transferring useful information to the production system to speed it up and improve it.

These improvements of the production system are possible thanks to the use of the paradigm of IoT. The IoT paradigm that is another pillar of Industry 4.0 is the extension of the Internet to real objects. The goal is to incorporate transparently and seamlessly a large number of different and heterogeneous end systems, while providing open access to selected subsets of data for the development of a large number of digital services.

Fig. 5 Individuals from Lissajous knot Pareto optimal sget

To date, the concept of Industry 4.0 and SM, and consequently also that of IoT, AM, and the other pillars, is applied in various production fields, while this still does not happen in other traditional artisan production sectors. One of them is the jeweler industry. This work has the main purpose of starting a first approach to the use of these new technologies in this field.

An important aid for the development of the Industry 4.0 has been provided by the introduction of CAD (computer-aided design) software. They have allowed a notable growth in many fields of design, including that of jewelry. The CAD system permits the designers to create and show extremely complex objects characterized by a precision of the details typical of the design stage rather than those in the conceptual design stage.

Fig. 7 Octopus interface. a Pareto set approximation. b Genetic diversification. c Convergence parameter

Most of these systems cannot allow the exploration of the design because the dynamic transformation of the shape and the graphical reinterpretation that are not supported. In light of this, the phase characterized by the creation of the conceptual design, where the designers develop the ideas and formulate the possibilities, is implemented with hand sketches. Nevertheless, the new needs of the users have allowed the beginning of a new distinctive method of design based on the parametric design (PD).

PD is a tool that requests an explicit visual dataflow in the form of graph supporting the designers by allowing a wide design exploration of the possible objects. The dataflow permits modeling a design object as a constrained collection of schemata that are represented in the form of a graph, called Direct Acyclic Graph (DAG). Parametric design allows the exploration of a wider range of design possibilities than traditional processes, helping human creativity and ensuring design variations that are obtained simply by changing the input parameters.

Fig. 8 Upper quartile of the non-dominated solutions

Industry 4.0 and the nine pillars that characterize it are today a key topic for research and technological development. The purpose of this research is to contribute to the development of new open-source technologies by allowing an everincreasing number of users to approach the concept of smart manufacturing and to improve and integrate the systems available today.

The research presented addresses for 3 of the nine pillars, simulations (for multi-objective optimization), and additive manufacturing to physicalize the optimized object, and particular attention has been given to system integration with the aim of better connecting different software and fundamental processes for the smart manufacturing sector.

Multi-objective optimization and rapid prototyping for jewelry industry: methodologies and case studies

Francesca Bertacchini¹, Eleonora Bilotta², Francesco Demarco², Pietro Pantano², Carmelo Scuro²

^{1 Department of Mechanical, Energy and Management Engineering, University of Calabria, Rende, Italy}

^{2 Department of Physics, University of Calabria, Rende, Italy}

Fig. 1 A schematic representation of the adopted logic

The new research and technologies that have ensured the digitalization of industries and the introduction of smart manufacturing are still characterized by poorly studied processes. In particular, communication and integration between different platforms, which form the ecosystem of smart manufacturing, are subject to various communication problems.

The research conducted and propounded in this article is based on the implementation of an integrated manufacturing system that involves parametric modeling, optimization, and additive manufacturing. The ecosystem analyzed guarantees communication between IT platforms such as Rhino-Grasshopper, for parametric modeling, and PreForm, slicing software for Formlab’s stereolithographic 3D printers.

For this purpose, C# scripts have been implemented in order to solve optimization problems in 3D modeling of objects and to guarantee integration between the two platforms. The latter script is configured as a real add-in for Rhino whose advantages are easily demonstrated thanks to the large number of recursive operations that are automated.

Fig. 2 Integration process

Industry 4.0 is a way in the academic and research world to call and identify the fourth industrial revolution that is happening today. This industrial revolution, and the consequent digitalization of the industry, is based on nine pillars including Internet of Things (IoT), big data, cloud, system integration, augmented reality, cyber security, autonomous robot simulation, and additive manufacturing (AM).

In this specific field, it often refers to Industry 4.0 related to production integrated with computer systems the term smart manufacturing (SM). It allows the industry to incorporate the entire product life cycle within the production chain while simultaneously changing the worker’s activities and object design.

Fig. 4 Visual scripting Lissajous Pareto optimal set

This abovementioned concept is typical of another pillar of Industry 4.0, the possibility of guaranteeing the simulation of the finished object before it is made. Industry 4.0 is based on the opportunity to use digital technologies in order to analyze data in real time, transferring useful information to the production system to speed it up and improve it.

These improvements of the production system are possible thanks to the use of the paradigm of IoT. The IoT paradigm that is another pillar of Industry 4.0 is the extension of the Internet to real objects. The goal is to incorporate transparently and seamlessly a large number of different and heterogeneous end systems, while providing open access to selected subsets of data for the development of a large number of digital services.

Fig. 5 Individuals from Lissajous knot Pareto optimal sget

To date, the concept of Industry 4.0 and SM, and consequently also that of IoT, AM, and the other pillars, is applied in various production fields, while this still does not happen in other traditional artisan production sectors. One of them is the jeweler industry. This work has the main purpose of starting a first approach to the use of these new technologies in this field.

An important aid for the development of the Industry 4.0 has been provided by the introduction of CAD (computer-aided design) software. They have allowed a notable growth in many fields of design, including that of jewelry. The CAD system permits the designers to create and show extremely complex objects characterized by a precision of the details typical of the design stage rather than those in the conceptual design stage.

Fig. 7 Octopus interface. a Pareto set approximation. b Genetic diversification. c Convergence parameter

Most of these systems cannot allow the exploration of the design because the dynamic transformation of the shape and the graphical reinterpretation that are not supported. In light of this, the phase characterized by the creation of the conceptual design, where the designers develop the ideas and formulate the possibilities, is implemented with hand sketches. Nevertheless, the new needs of the users have allowed the beginning of a new distinctive method of design based on the parametric design (PD).

PD is a tool that requests an explicit visual dataflow in the form of graph supporting the designers by allowing a wide design exploration of the possible objects. The dataflow permits modeling a design object as a constrained collection of schemata that are represented in the form of a graph, called Direct Acyclic Graph (DAG). Parametric design allows the exploration of a wider range of design possibilities than traditional processes, helping human creativity and ensuring design variations that are obtained simply by changing the input parameters.

Fig. 8 Upper quartile of the non-dominated solutions

Industry 4.0 and the nine pillars that characterize it are today a key topic for research and technological development. The purpose of this research is to contribute to the development of new open-source technologies by allowing an everincreasing number of users to approach the concept of smart manufacturing and to improve and integrate the systems available today.

The research presented addresses for 3 of the nine pillars, simulations (for multi-objective optimization), and additive manufacturing to physicalize the optimized object, and particular attention has been given to system integration with the aim of better connecting different software and fundamental processes for the smart manufacturing sector.