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Adaptive slicing is a key step in 3D printing as it is closely related to the building time and the surface quality. This study aims to develop an adaptive layering algorithm that can coordinate the optimization of printing quality and efficiency to meet different printing needs.

A multiobjective optimization model is established for printing quality, printing time and layer height based on the variation of surface features, profile slope and curvature of the model. The optimal solution is found by an improved method combining Newton's method and gradient method and adapts to different printing requirements by adjusting the parameter thresholds.

Several benchmarks are applied to verify this new method. The proposed method has also been compared with the uniform layering method, it reduces the volume error by 46.4% and shortens the printing time by 28.1% and is compared with five existing adaptive layering methods to demonstrate its superior performance.

Compared with other methods with only one layered result, this method is a demand-oriented algorithm that can obtain different results according to different needs and it can reach a trade-off between the building time and the surface quality.

Presents development and characterisation of a new metal/polymer composite material for use in fused deposition modelling (FDM) rapid prototyping process with the aim of application to direct rapid tooling. The work represents a major development in reducing the cost and time in rapid tooling.

The material consists of iron particles in a nylon type matrix. The detailed formulation and characterisation of the thermal properties of the various combinations of the new composites are investigated experimentally. Results are compared with other metal/polymer composites used in rapid tooling.

The feedstock filaments of this composite have been produced and used successfully in the unmodified FDM system for direct rapid tooling of injection moulding inserts. Thermal properties are found to be acceptable for rapid tooling applications for injection moulding.

Introduces an entirely new metal based composite material for direct rapid tooling application using FDM RP system with desired thermal properties and characteristics. This will reduce the cost and time of manufacturing tooling inserts and dies for injection moulding.

This paper presents an investigation on the development of different pattern placement strategies in robotic palletisation of box packages in the packaging industry with practical implementations for one, two, four and five block patterns with the aim of improving the operational efficiency in robotic palletisation.

The work involves considering the gripper design and maximum number of picks and various process parameters that affect the robotic implementation of pallet patterns and develops a methodology to form different patterns for a given pallet size.

The proposed methodology represents an efficient approach for pallet pattern implementation and results in reduced number of placements required for a given number of boxes per layer and reduced time for palletisation.

The paper introduces a novel technique for pallet loading problem (PLP) considering the physical aspects and restrictions encountered when using the robot and the gripper size to generate the pattern on the pallet. Traditional solutions of PLP do not consider these aspects in pattern placements.

Rapid prototyping (RP) has been given focus during dynamic market conditions, as it largely helps to compress product development time. RP contains the potential to achieve environmentally friendlier operations. However, RP processes are not environmentally friendlier, as the possibilities of toxicological health and environmental risks while handling and disposing of raw material remain unresolved. This study aims to select environmentally friendlier processes without compromising required mechanical properties. Some of the RP processes considered in this study are selective laser sintering (SLS), stereo lithography apparatus (SLA), three-dimensional printing (3DP) and laser engineered net shaping (LENS).

A conceptual model comprising 25 criteria (both traditional and environmental) has been developed. An expert team was formed to evaluate the environmental performance of RP processes using the developed conceptual model. Analytic network process–technique for order preference by similarity to an ideal solution-based hybrid methodology has been adopted for this purpose. Further, to overcome ambiguity and subjectivity nature of judgment, fuzzy set concepts have been adopted. Finally, a decision support system has been developed using MATLAB software to mitigate the associated computational difficulty.

The detailed analysis of criterion weights revealed that the expert team has assigned higher importance to environmental criteria over traditional criteria. Based on environmental considerations, ranking has been generated as SLA-SLS-3DP-LENS.

Only point-to-point and discrete fusion-based RP process have been considered in this study to demonstrate the developed conceptual model. Also, expert knowledge has been taken to rate some of the environmental criteria. In the near future, by conducting environmental studies, these criteria can be substituted with real data to improve accuracy of RP process selection.

Reported studies in RP process selection in literature were conducted considering mainly the various traditional criteria. In this study, the environmental criteria have also been considered along with traditional criteria. This study takes the initiative toward sustainability studies in RP processes. Also, detailed inferences have been derived and the results have been compared with the existing studies and this is the novel contribution of this study.

The purpose of this study is to highlight the direct fabrication of rapid tooling (RT) with desired mechanical, tribological and thermal properties using fused deposition modelling (FDM) process. Further, the review paper demonstrated development procedure of alternative feedstock filament of low-cost composite material for FDM to extend the range of RT applications.

The alternative materials for FDM and their processing requirements for fabrication in filament form as reported by various researchers have been summarized. The literature demonstrates the role of various post-processing techniques on surface finish of FDM prints. Further, low-cost materials for feedstock filament have been investigated experimentally to check their adaptability/suitability for commercial FDM setup. The approach was to realize the requirements of FDM (melt flow rate, flexibility, stiffness, glass transition temperature and mechanical strength), necessary for the successful run of an alternative filament. The effect of constituents (additives, plasticizers, surfactants and fillers) in polymeric matrix on mechanical, tribological and thermal properties has been investigated.

It is possible to develop composite material feedstock as filament for commercial FDM setup without changing its hardware and software. Surface finish of the parts can further be improved by applying various post-processing techniques. Most of the composite parts have high mechanical strength, hardness, thermal stability, wear resistant and better bond formation than standard material parts.

Future research may be focused on improving the surface quality of parts fabricated with composite feedstock, solving issues related to the uniform distribution of filled materials during the fabrication of feedstock filament which in turns further increases mechanical strength, high dimensional stability of composite filament and transferring the technology from laboratory scale to various industrial applications.

Potential applications of direct fabrication with RT includes rapid manufacturing (RM) of metal-filled parts and ceramic-filled parts (which have complex shape and cannot be rapidly made by any other manufacturing techniques) in the field of biomedical and dentistry.

This new manufacturing methodology is based on the proper selection and processing of various materials and additives to form high-performance, low-cost composite material feedstock filament (which fulfil the necessary requirements of FDM process). Finally, newly developed feedstock filament material has both quantitative and qualitative advantage in RT and RM applications as compared to standard material filament.

This paper seeks to present an investigation on building controlled drug delivery device (DDD) matrix using fused deposition modelling (FDM) rapid prototyping (RP) process. The focus of the study is on the effect of FDM fabricated macro‐features of reservoir‐matrix DDD models on the drug release rates through the diffusion process.

Using various parameters involved with FDM, polymeric DDD matrices with different macro‐features are designed and fabricated on the FDM3000 machine. Experiments are conducted to study the release characteristics and porosity of the fabricated models with a model drug and to see how they are affected by FDM build parameters.

Experimental results show that FDM parameters, raster gap and raster angle, play significant roles in controlling the structure and drug release characteristics of the FDM fabricated DDDs. The experimental observations reveal that appropriate FDM parameters can be selected to fabricate controlled DDD device with desired release rate of drug and the desired period of operation of the device.

The paper introduces a novel application of FDM RP system in the development and fabrication of polymeric controlled DDDs. The controlled release of drugs is an important area in which RP techniques can be successfully used in developing models of release matrix for DDDs with added benefits of accuracy, uniformity and low costs compared with conventional methods.

The purpose of this paper is to develop a methodology to analyze the total sintering energy (TSE) required for manufacturing a part in metal powder-based additive manufacturing (AM) processes and optimize AM processes for minimizing total energy and form errors of AM parts while maximizing part strength.

The paper uses a computational geometry approach to determine the TSE expended for manufacturing a metal AM part. The stereolithography (STL) file of a part is converted into a voxel data structure and the total sintering volume (TSV) is computed from the voxel representation. The TSE is then calculated from the TSV using the material property information of the metal powder.

The TSE of an AM part is calculated for different slice thickness and part orientations, and the correlation of the total energy to these parameters is calculated. Using these correlations, the AM process is optimized to calculate the optimal values of slice thickness and part orientation which would result in lower process energy, lower part form errors and higher part strength.

The methodology presented in this paper provides AM users a roadmap to predict the energy required for manufacturing a part. In addition, the optimization model will allow engineers to manufacture precision parts which satisfy their design specifications with minimal energy expenditure.

Fused deposition modelling (FDM) is the most economical additive manufacturing technique. The purpose of this paper is to describe a detailed review of this technique. Total 211 research papers published during the past 26 years, that is, from the year 1994 to 2019 are critically reviewed. Based on the literature review, research gaps are identified and the scope for future work is discussed.

Literature review in the domain of FDM is categorized into five sections – (i) process parameter optimization, (ii) environmental factors affecting the quality of printed parts, (iii) post-production finishing techniques to improve quality of parts, (iv) numerical simulation of process and (iv) recent advances in FDM. Summary of major research work in FDM is presented in tabular form.

Based on literature review, research gaps are identified and scope of future work in FDM along with roadmap is discussed.

In the present paper, literature related to chemical, electric and magnetic properties of FDM parts made up of various filament feedstock materials is not reviewed.

This is a comprehensive literature review in the domain of FDM focused on identifying the direction for future work to enhance the acceptability of FDM printed parts in industries.

Combination of advanced imaging, designing and manufacturing techniques has been rapidly developed in recent years for diagnostic and therapeutic purposes for medical devices. The purpose of this paper is to present a methodology for design and fabrication procedure of medical models using computer‐aided design (CAD) and fused deposition modeling (FDM) technique for application in the mandibular reconstructive surgery.

Case studies of patients with mandibular defects are examined using CAD model construction including data acquisition from computerized tomography scan and data processing. Furthermore, the effect of advanced manufacturing parameters settings in FDM methodology is investigated.

The models were used in assisting the surgeons in their reconstruction planning. A significant improvement regarding the success and convenience in surgery planning been reported.

This paper explores the application and viability of FDM rapid prototyping technology for fabrication of complex mandibular models used for reconstructive surgery.

The purpose of this paper is to propose a systematic study to formulate the cost of prototypes manufactured through rapid prototyping (RP) an fused deposition modeling (FDM) 3D printer in a university lab.

The paper has a theoretical‐conceptual approach. This approach is carried out by studying and proposing a methodology for calculating the cost of pieces prototyped an FDM 3D printer.

This work originated from a gap in literature to establish a way to calculate the price of RP pieces from FDM 3D printers in universities' labs, since no similar work has dealt with this RP technology and has not taken into account the costs of post‐processing step. The results suggest that the formulation may be used to calculate price of prototyped pieces through FDM 3D printer.

The systematic approach proposed by this research to formulate cost for the RP pieces is initially oriented only to modelling technique by FDM 3D printer. Considerations on operator's and designer's hourly rates are those practiced in Brazil, which may differ from other countries.

The paper's scientific contribution is a specific formulation to calculate price of prototyped pieces through FDM considering the post‐processing way, which differs from previous published works. The formulation implies that the execution times and the amount of material used were obtained by internal calculation of the tested machine. This is different from what has been already studied by previous literature which considers an index that encompasses the machine operation cost in function of time. It is aimed that the results obtained here are accurate, since error margins of the process variables are reduced.