Abstract Ceramic materials are gaining relevance in Additive Manufacturing (AM), although the lack of standardized process parameters limits the repeatability and comparability of printed parts. This study proposes an optimization procedure for the fabrication of alumina (Al₂O₃) components using Fused Deposition Modelling (FDM) with a [...]

Abstract This work presents a fused-filament fabrication (FFF) hot end that combines an unrestricted-rotation C-axis with a rectangular-slot nozzle and an induction-heated melt sleeve. The architecture replaces the popular resistive cartridge and heater block design with an external coil that induces eddy-current heating in a [...]

Abstract As additive manufacturing technologies continue to gain ground in industrial applications, the need for the accurate metrological evaluation of parts produced with advanced materials becomes increasingly critical. In this context, non-contact metrology plays a key role. This research investigates the performance of conoscopic holography [...]

Abstract Surface quality in material extrusion of polymers (MEX/P) plays a critical role in determining the functional performance of printed parts, especially in components that must work together and in sectors such as medical and aerospace. Predicting surface quality before printing shall be therefore considered [...]

Abstract Additive manufacturing (AM) has faced challenges in achieving the part accuracy required for industrial adoption. Most research has focused on offline inspection of geometric deviations in test parts. This paper introduces a novel approach to enhance part accuracy and process control in Polymer Extrusion [...]

Abstract:  The industrial adoption of material extrusion of polymers (MEX/P) is hindered by the geometric quality of manufactured parts. Contact image sensors (CISs), commonly used in flatbed scanners, have been proposed as a suitable technology for layer-wise characterization of contour deviations, paving the way for [...]

Abstract The variety of equipment implementing laser triangulation technology for 3D scanning makes it difficult to analyse their performance, comparability, and traceability. In this study, three laser triangulation sensors arranged in different configurations are analysed using high precision spheres made of different materials and surface [...]

Abstract Additive Manufacturing (AM) is advancing technologically towards the production of components for high-demand mechanical applications with stringent dimensional accuracy, leveraging metallic and ceramic raw materials. The AM process for ceramic components, known as Ultraviolet Laser Stereolithography (SLA), enables the fabrication of unique parts or [...]

Abstract The implementation of in-situ sensing solutions to monitor additive manufacturing processes has seen a significant surge in recent years, notably in processes where localised heating is used. These technologies, however, have not always yielded accurate information about final part quality, due to differences between [...]

Abstract The characteristics of additively manufactured parts (topological optimisation, freedom of design …) present a challenge from a metrological point of view. In this respect, non-contact inspection is of great importance for the rapid verification of this type of parts. However, their particular characteristics (stair-effect, [...]

Abstract Material Extrusion (MEX) currently stands as the most widespread Additive Manufacturing (AM) process, but part quality deficiencies remain a barrier to its generalized industrial adoption. Quality control in MEX is a complex task as extrusion performance impacts the consistency of mechanical properties and the [...]

Abstract The purpose of this paper is to provide a new procedure for in-plane compensation of geometric errors that often appear in the layers deposited by an additive manufacturing (AM) process when building a part, regardless of the complexity of the layer geometry. The procedure [...]

Abstract The great geometric complexity that additive manufacturing allows in parts, together with the possibility of combining several materials in the same part, establishes a new design and manufacturing paradigm. Despite the interest of many leading sectors, the lack of standardization still makes it necessary [...]

Abstract The lack of geometric and dimensional accuracy of parts produced by additive manufacturing (AM) is directly related to the machine, material and process used. This paper aims to propose a method for the analysis and compensation of machine-related geometric errors applicable to any AM [...]

Abstract The lack of standardization and the low quality of parts produced by Additive Manufacturing requires in certain cases the use of in-situ monitoring techniques based on the use of different types of sensors, each of which has advantages and disadvantages depending on the type [...]

Abstract The advantages of non-contact digitising systems over contact systems are undeniable. They allow capturing more information per unit of time with less accessibility problems and without alter the digitised surface. Although many of these systems have been developed with the aim of replacing contact [...]

Abstract Traditionally, 3D digitizing sensors have been based on contact measurement. Given the disadvantages of this type of measurement, non-contact sensors such as structured light sensors have gained the attention of many sectors in recent years. The fact that their metrological performance is affected by [...]

Abstract The surface quality verification of mechanical components is an essential activity in many applications where surface performance plays an important role in the functional behaviour of the part. Although many of the verification techniques commonly employed are based on the use of contact roughness [...]

Abstract The use of non-contact scanning equipment in metrology and in dimensional and geometric inspection applications is increasing due to its ease of use, the speed and density of scans, and the current costs. In fact, these technologies are becoming increasingly dominant in the industrial [...]

Abstract The improvement of industrial manufacturing processes requires measurement procedures and part inspection tasks to be faster and faster while remaining effective. In this sense, the capabilities of noncontact measuring systems are of great help, not only because of the great amount of data they [...]

Abstract A notable constraint to the industrial application of additive manufacturing processes is the lack of geometric accuracy of the parts produced. In-situ inspection systems, therefore, need to be developed to detect and compensate for any geometric deviations that appear during the process. This article [...]

Abstract Among the different methodologies used for performance control in precision manufacturing, the measurement of metrological test artefacts becomes very important for the characterization, optimization and performance evaluation of additive manufacturing (AM) systems. The purpose of this study is to design and manufacture several benchmark [...]

Abstract The significant improvements made in additive manufacturing (AM) techniques since their beginnings, coupled with its intrinsic advantages, have resulted in a technology that stands out as most suitable for applications in leading sectors today. In addition to some of the properties of the parts, [...]

Abstract Metal Additive Manufacturing (AM) processes are developing quickly. These processes have several attractive qualities, however, the quality of manufactured parts still remains a major issue that needs to be addressed if it is to become a prevalent technology in the industry. In some powder [...]

Abstract: This paper presents the integration of a conoscopic holography sensor (CH) in a machining centre (MC) by means of a centralized control on the machine’s CNC (CNC centralized control). Besides the installation and extrinsic calibration of the sensor, the primary focus is the automation of the freeform digitizing [...]

Abstract: This work analyses the directional effect shown by the high-density point clouds digitized with a conoscopic holography (CH) sensor. The asymmetric shape of the laser spot for this sensor yields directionality to appear along the largest spot dimension and to occur repeatedly under different working conditions. To study [...]