Ontology for smart 4D printed material systems and structures synergically applied with generative artificial intelligence for creativity promotion

This study presents a versatile ontology for describing all kinds of smart or stimuli-responsive 4D printed material systems and structures. The different components of the ontology, namely: initial geometry and shape, shape-morphing principle(s), triggering stimuli, intermediate/final geometry and shape, 4D material and printing or additive manufacturing technology, are enumerated and classified. Accordingly, a codification system for schematically illustrating the actuation cycle of 4D printed material systems and structures, and shape-morphing devices in general, is proposed. The systematic application of the ontology to a relevant set of examples helps to demonstrate its utility and adaptability to many different types of 4D printed objects. It demonstrates that the ontology and codification schemes developed in this research can serve a comprehensive classification tool for the emergent field of 4D printing. It is the first ontology capable of representing the multiple actuation steps of complex 4D printed devices and actuators, in which several metamorphoses may be achievable, due to combinations of different shape-morphing principles and triggering stimuli. To this end, a single line of code is required. A glossary is provided to support its implementation and application. Besides, the usability of the ontology and related codification by a generative artificial intelligence (AI) for supporting engineering design tasks is explored and validated through a set of examples and an industrial use case. This work is expected to provide a universal language to facilitate the communication in the 4D materials and printing field, as well as a synergic generative AI-based methodology for creativity promotion linked to innovative smart 4D printed material systems and structures

Shaping ability of Reciproc and TF Adaptive systems in severely curved canals of rapid microCT-based prototyping molar replicas

Objective: To evaluate the shaping ability of Reciproc and Twisted-File Adaptive systems in rapid prototyping replicas. Material and Methods: Two mandibular molars showing S-shaped and 62-degree curvatures in the mesial root were scanned by using a microcomputed tomography (μCT) system. The data were exported in the stereolitograhic format and 20 samples of each molar were printed at 16 µm resolution. The mesial canals of 10 replicas of each specimen were prepared with each system. Transportation was measured by overlapping radiographs taken before and after preparation and resin thickness after instrumentation was measured by μCT. Results: Both systems maintained the original shape of the apical third in both anatomies (P>0.05). Overall, considering the resin thickness in the 62-degree replicas, no statistical difference was found between the systems (P>0.05). In the S-shaped curvature replica, Reciproc significantly decreased the thickness of the resin walls in comparison with TF Adaptive. Conclusions: The evaluated systems were able to maintain the original shape at the apical third of severely curved mesial canals of molar replicas

Wireless Sensors for Intraoral Force Monitoring

A device for wireless intraoral forces monitoring is presented. Miniaturized strain gauge sensors are used for the measurements of forces applied by tongue and lips. A sensor interface IC is able to multiplex among four sensors and a low energy transmission module, equipped with an ARM Cortex–M0 core, is used for signal elaboration and remote wireless data transmission using Bluetooth® Low Energy standard protocol. The main novelty rely in the dynamic correction of the output corrupted by the prestrain issue. Moreover, the device shows a reduced dimension and the ability to transmit data wirelessly, without the use of external cables normally used in state-of-the-art intraoral monitoring devices

Product Lifecycle Management Strategy for the Definition and Design Process of Face Implants Oriented to Specific Patients

Part 2: Collaborative Environments and New Product DevelopmentInternational audienceThe main purpose of this research was oriented to generate a structured model from an organizational vision to the definition and development of precise osteosynthesis prosthesis. Implants were adapted to the Colombian population anthropometry allowing fracture reductions and craniofacial defects corrections based on technologies for specific patients. This research was developed taking into account the first three PLM stages: Imagination, definition, and realization. Procedures, stages, roles, and activities that take part in the design and pre-surgical planning were identified for the patient-specific implants PSI, carried out through a study case. It was established as a definition model for design and fabrication process of patient-specific implants (PSI). It was possible that technology included in a collaborative workflow wherein the roles which intervene in the design process and the pre-surgical planning were related. The ability to design implants for specific patients and surgical guides was obtained different pathology situations including face trauma. According to the PLM strategy for designing custom implant, it would be possible to build innovation capabilities. With those, an organization could generate a collaborative workflow integrating stages, roles, activities, applying technology and local human resource. Further work related to the subject is necessary to enhance the process by iteration and improve the clinical cases management

Explicit parametric solutions of lattice structures with proper generalized decomposition (PGD)

Architectured materials (or metamaterials) are constituted by a unit-cell with a complex structural design repeated periodically forming a bulk material with emergent mechanical properties. One may obtain specific macro-scale (or bulk) properties in the resulting architectured material by properly designing the unit-cell. Typically, this is stated as an optimal design problem in which the parameters describing the shape and mechanical properties of the unit-cell are selected in order to produce the desired bulk characteristics. This is especially pertinent due to the ease manufacturing of these complex structures with 3D printers. The proper generalized decomposition provides explicit parametic solutions of parametric PDEs. Here, the same ideas are used to obtain parametric solutions of the algebraic equations arising from lattice structural models. Once the explicit parametric solution is available, the optimal design problem is a simple post-process. The same strategy is applied in the numerical illustrations, first to a unit-cell (and then homogenized with periodicity conditions), and in a second phase to the complete structure of a lattice material specimen