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This paper aims to present a reverse engineering (RE) approach for three-dimensional (3D) model reconstruction and fast prototyping (FP) of broken chess pieces.

A case study involving a broken chess piece was selected to demonstrate the effectiveness of the proposed unconventional RE approach. Initially, a laser 3D scanner was used to acquire a (non-uniform rational B-spline) surface model of the object, which was then processed to develop a parametric computer aided design (CAD) model combined with geometric design and tolerancing (GD&T) technique for evaluation and then for FP of the part using a computer numerical controlled (CNC) machine.

The effectiveness of the proposed approach for reconstruction and FP of rotational parts was ascertained through a sample part. The study demonstrates non-contact data acquisition technologies such as 3D laser scanners together with RE systems can support to capture the entire part geometry that was broken/worn and developed quickly through the application of computer aided manufacturing principles and a CNC machine. The results indicate that design communication, customer involvement and FP can be efficiently accomplished by means of an integrated RE workflow combined with rapid product development tools and techniques.

This research established a RE approach for the acquisition of broken/worn part data and the development of parametric CAD models. Then, the developed 3D CAD model was inspected for accuracy by means of the GD&T approach and rapidly developed using a CNC machine. Further, the proposed RE led FP approach can provide solutions to similar industrial situations wherein agility in the product design and development process is necessary to produce physical samples and functional replacement parts for aging systems in a short turnaround time.

The purpose of this paper is to implement a new process aimed at the design and production of orthopaedic devices fully manufacturable by additive manufacturing (AM). In this context, the use of generative algorithms for parametric modelling of additively manufactured textiles (AMTs) also has been investigated, and new modelling solutions have been proposed.

A new method for the design of customised elbow orthoses has been implemented. In particular, to better customise the elbow orthosis, a generative algorithm for parametric modelling and creation of a flexible structure, typical of an AMT, has been developed.

To test the developed modelling algorithm, a case study based on the design and production of an elbow orthosis made by selective laser sintering was investigated. The obtained results have demonstrated that the implemented algorithm overcomes many drawbacks typical of the traditional computer aided design (CAD) modelling approaches. The parametric CAD model of the orthosis obtained through the new approach is characterised by a flexible structure with no deformations or mismatches and has been effectively used to produce the prototype through AM technologies.

The obtained results present innovative elements of originality in the CAD modelling sector, which can contribute to solving problems related to modelling for AM in different application fields.

Paint path planning for industrial robots is critical for uniform paint distribution, process cycle time and material waste, etc. However, paint path planning is still a costly and time‐consuming process. Currently paint path planning has always caused a bottle‐neck for manufacturing automation because typical manual teaching methods are tedious, error‐prone and skill‐dependent. Hence, it is essential to develop automated tool path‐planning methods to replace manual paint path planning. The purpose of this paper is to review the existing automated tool path‐planning methods, and investigate their advantages and disadvantages.

The approach takes the form of a review of automated tool path‐planning methods, to investigate the advantages and disadvantages of the current technologies.

Paint path planning is a very complicated task considering complex parts, paint process requirements and complicated spraying tools. There are some research and development efforts in this area. Based on the review of the methods used for paint path planning and simulation, the paper concludes that: the tessellated CAD model formats have many advantages in paint path planning and paint deposition simulation. However, the tessellated CAD model formats lack edge and connection information. Hence, it may not be suitable for some applications requiring edge following, such as welding. For the spray gun model, more complicated models, such as 2D models, should be used for both path planning and paint distribution simulation. Paint path generation methods should be able to generate a paint path for complex automotive parts without assumptions, such as presupposing a part with a continuous surface.

The paper makes possible automated path generation for spray‐painting process using industrial robots such that the path‐planning time can be reduced, the product quality improved, etc.

The paper provides a useful review of current paint path‐planning methodologies based on the CAD models of parts.

The purpose of this paper is to present an integrated design approach for rapid product development (RpD) of a broken product.

Reverse engineering (RE), re‐engineering (ReE) and RpD systems have been incorporated to infuse agile characteristics in the proposed design and development process. A case study involving a broken clutch shoe was selected to demonstrate the efficacy of the proposed integrated approach.

Integration of RE, ReE and RpD presented an unconventional approach towards achieving reduced lead times for design and development of products. Agile characteristics have been manifested for the broken clutch shoe by retrieval of a digitized parametric computer aided design (CAD) model. Moreover, development and selection of an enhanced feasible design (M₃) as well as delivery of the corresponding prototype was accomplished just in one week.

The proposed integrated approach for RpD can provide solutions to similar industrial situations wherein agility in the product design and development process can be infused so that the developed part can be delivered quickly to the customer at the reduced time and costs.

This paper describes the use of parametric modelling techniques in the design of drinking bottles. A customised application programme is developed and integrated for the design and manufacture of a blow mould bottle within a proprietary CAD/CAM software named Duct5. One such conceptual design is physically realized and verified through the use of the stereolithography technique. Overall, by equipping designers with a library of “bottle‐design” features from a CAD/CAM system, the design period is shortened and simplified, and the same geometrical data can be passed downstream for manufacturing.

Integrates CAD/CAM, production control and process control in a case study involving manufacturing automation. The manufacturing firm is a distributed cellular system operating in a produce‐to‐order environment. Combines a parametric CAD software with global variables and global relations to achieve a design automation. Results obtained from design automation are transmitted to update the design model and the associative manufacturing model. In addition, scheduling and control are also integrated in the system. Distinguishes three scheduling levels: static scheduling, rescheduling, and real‐time scheduling. For a distributed and effective reason, the distributed shifting bottleneck procedure (DSBP) is adopted as the static scheduler and rescheduler, and the LRPT (longest bottleneck processing time) despatching rule is adopted as the real time despatching rule. FInally, introduces the configuration of the system including the flexible manufacturing cell architecture and the input buffer device. Uses a PLC programming toll that follows the IEC 1131‐3 standard to implement cell controllers. The above implementation aims to easily and effectively execute the CIM system.

This paper aims to introduce a process chain spanning from scanned data to computer-aided engineering and further required simulations up to the subsequent production. This approach has the potential to reduce production costs and accelerate the procedure.

A parametric computer-aided design (CAD) model of the flyer wearing a wingsuit is created enabling easy changes in its posture and the wingsuit geometry. The objective is to track the influence of geometry changes in a timely manner for following simulation scenarios.

At the final stage, the two-dimensional (2D) pattern cuts were derived from the developed three-dimensional (3D) wingsuit, and the results were compared with the conventional ones used in the first stages of the wingsuit development.

Proposing a virtual development process chain is challenging; apart from the fact that the CAD construction of a wingsuit flyer – in itself posing a complicated task – is required at a very early stage of the procedure.

A three-dimensional (3D) printed custom-fit respirator mask has been proposed as a promising solution to alleviate mask-related injuries and supply shortages during COVID-19. However, creating a custom-fit computer-aided design (CAD) model for each mask is currently a manual process and thereby not scalable for a pandemic crisis. This paper aims to develop a novel design process to reduce overall design cost and time, thus enabling the mass customisation of 3D printed respirator masks.

Four data acquisition methods were used to collect 3D facial data from five volunteers. Geometric accuracy, equipment cost and acquisition time of each method were evaluated to identify the most suitable acquisition method for a pandemic crisis. Subsequently, a novel three-step design process was developed and scripted to generate respirator mask CAD models for each volunteer. Computational time was evaluated and geometric accuracy of the masks was evaluated via one-sided Hausdorff distance.

Respirator masks were successfully generated from all meshes, taking <2 min/mask for meshes of 50,000∼100,000 vertices and <4 min for meshes of ∼500,000 vertices. The average geometric accuracy of the mask ranged from 0.3 mm to 1.35 mm, depending on the acquisition method. The average geometric accuracy of mesh obtained from different acquisition methods ranged from 0.56 mm to 1.35 mm. A smartphone with a depth sensor was found to be the most appropriate acquisition method.

A novel and scalable mass customisation design process was presented, which can automatically generate CAD models of custom-fit respirator masks in a few minutes from a raw 3D facial mesh. Four acquisition methods, including the use of a statistical shape model, a smartphone with a depth sensor, a light stage and a structured light scanner were compared; one method was recommended for use in a pandemic crisis considering equipment cost, acquisition time and geometric accuracy.

The purpose of this paper is to establish an adaptive assembly, to realize the adaptive changing of the models and to improve the flexibility and reliability of assembly change. For a three-dimensional (3D) computer-aided design (CAD) assembly in a changing process, there are two practical problems. One is delivering parameters’ information not smoothly. The other one is to easily destroy an assembly structure.

The paper establishes associated parameters design structure matrix of related parts, and predicts possible propagation paths of the parameters. Based on the predicted path, structured storage is made for the affected parameters, tolerance range and the calculation relations. The study combines structured path information and all constrained assemblies to build the adaptive assembly, proposes an adaptive change algorithm for assembly changing and discusses the extendibility of the adaptive assembly.

The approach would improve the flexibility and reliability of assembly change and be applied to different CAD platform.

The examples illustrate the construction and adaptive behavior of the assembly and verify the feasibility and reasonability of the adaptive assembly in practical application.

The adaptive assembly model proposed in the paper is an original method to assembly change. And compared with other methods, good results have been obtained.

The purpose of this paper is to present a Design for Additive Manufacturing (DfAM) methodology that connects several methods, from geometrical design to post-process selection, into a common optimisation framework.

A design methodology is formulated and tested in a case study. The outcome of the case study is analysed by comparing the obtained results with alternative designs achieved by using other design methods. The design process in the case study and the potential of the method to be used in different settings are also discussed. Finally, the work is concluded by stating the main contribution of the paper and highlighting where further research is needed.

The proposed method is implemented in a novel framework which is applied to a physical component in the case study. The component is a structural aircraft part that was designed to minimise weight while respecting several static and fatigue structural load cases. An addition goal is to minimise the manufacturing cost. Designs optimised for manufacturing by two different AM machines (EOS M400 and Arcam Q20+), with and without post-processing (centrifugal finishing) are considered. The designs achieved in this study show a significant reduction in both weight and cost compared to one AM manufactured geometry designed using more conventional methods and one design milled in aluminium.

The method in this paper allows for the holistic design and optimisation of components while considering manufacturability, cost and component functionality. Within the same framework, designs optimised for different setups of AM machines and post-processing can be automatically evaluated without any additional manual work.