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The aim of this study is to first investigate the surface integrity of cylindrical rollers under grinding process and then design a reasonable superfinishing process that improve the anti-fatigue performance of cylindrical rollers by optimization of the surface integrity.

First, the white and dark layers produced by the grinding process is analyzed by microscope. Then, the influence of oilstone pressure on the stock removal, surface precision and crowned profile are explored. Finally, an optimal superfinishing process and a novel turnaround device are designed to improve surface integrity.

The experimental results show that as the oilstone pressure increases, the stock removal first increases and then remains stable. This hints that the stock removal of a single-time superfinishing process has an upper limit. In the current conditions, the maximum stock removal is 6 µm. Double-time superfinishing process and the turnover device can effectively eliminate the white and dark layers and improve the symmetric of roller profile. In addition, the surface precision is also improved.

The surface integrity of bearing rollers is very important to the application of industry field. The findings and the methods in the study can be helpful to improve the surface integrity of the bearing rollers.

To obtain a high-quality finished product model, three-dimensional (3D) printing needs to be optimized.

Based on back-propagation neural network (BPNN), the particle swarm optimization (PSO) algorithm was improved for optimizing the parameters of BPNN, and then the model precision was predicted with the improved PSO-BPNN (IPSO-BPNN) taking nozzle temperature, etc. as the influencing factors.

It was found from the experimental results that the prediction results of IPSO-BPNN were closer to the actual values than BPNN and PSO-BPNN, and the prediction error was smaller; the average error of dimensional precision and surface precision was 6.03% and 6.54%, respectively, which suggested that it could provide a reliable guidance for 3D printing optimization.

The experimental results verify the validity of IPSO-BPNN in 3D printing precision prediction and make some contributions to the improvement of the precision of finished products and the realization of 3D printing optimization.

The purpose of this paper is to develop a strategic approach with an intelligently integrated management system in advanced manufacturing industry to meet the requirements of high precise measurement tasks and essential measurement know-how within the sophisticated production systems.

The continuous development toward ever-higher precision and closer tolerances in the manufacture of workpieces is in line with the perspective of nanotechnology. To meet the metrological requirements new high precision intelligent measuring instruments have been developed, which are proposed in this paper.

In modern industrial production, need for high precision metrology at micro and nano scale provides high quality requirements as well. Therefore, while providing adequate metrology applications, good management of resources and environmental, energy consequences shall be addressed in an integrated manner with an integrated management system of quality, environment and energy.

Metrology as the measurement science provides the functional methodology for quality control under the defined specifications and standards. New levels of manufacturing precision are the key requirements to enable advanced machining processes that demands improved techniques of metrology.

The practical industrial use is now quite possible, but uncertainty and calibration with respect to certain questions still open. In various technical fields, there are increasingly new applications being mainly mechanical engineering, precision machining, biomedicine and precision engineering are mentioned.

This paper provides measurement results and experimenting a strategic approach to develop a smart integrated system applicable in manufacturing industry using the intelligent networking for the digital factory by first an inter-university network that accesses, cooperates and operates at distance in the laboratory of distant research laboratories that can be applicable to all other industrial organizations.

This study aims to optimize the manufacturing process to improve the manufacturing quality, costs and delivering time with the help of multiscale multiphysics modelling and simulation. Multiscale multiphysics-based modelling and simulations are receiving more and more interest by research community and the industry particularly in the context of increasing demands for manufacturing high precision complex products and understanding the intrinsic complexity in associated manufacturing processes.

In this paper, some modelling and analysis techniques using multiscale multiphysics modelling are presented and discussed.

Furthermore, the possibility of adopting the multiscale multiphysics modelling and simulation to develop the virtual machining system is evaluated, and further supported with an industrial case study on abrasive flow machining (AFM) of integrally bladed rotors using the techniques and system developed.

With the development of multiscale multiphysics-based modelling and simulation, it will enable effective and efficient optimisation of manufacturing processes and further improvement of manufacturing quality, costs, delivery time and the overall competitiveness.

A nut bolt joint is a primary device that connects mechanical components. The vibrations cause bolted joints to self-loosen. Created by motors and engines, leading to machine failure, and there may be severe safety issues. All the safety issues and self-loosen are directly and indirectly the functions of the accuracy and precision of the fabricated nut and bolt. Recent advancements in three-dimensional (3D) printing technologies now allow for the production of intricate components. These may be used technologies such as 3D printed bolts to create fasteners. This paper aims to investigate dimensional precision, surface properties, mechanical properties and scanning electron microscope (SEM) of the component fabricated using a multi-jet 3D printer.

Multi-jet-based 3D printed nut-bolt is evaluated in this paper. More specifically, liquid polymer-based nut-bolt is fabricated in sections 1, 2 and 3 of the base plate. Five nuts and bolts are fabricated in these three sections.

Dimensional inquiry (bolt dimension, general dimensions’ density and surface roughness) and mechanical testing (shear strength of nut and bolt) were carried out throughout the study. According to the ISO 2768 requirements for the General Tolerances Grade, the nut and bolt’s dimensional examination (variation in bolt dimension, general dimensions) is within the tolerance grades. As a result, the multi-jet 3D printing (MJP)-based 3D printer described above may be used for commercial production. In terms of mechanical qualities, when the component placement moves from Sections 1 to 3, the density of the manufactured part decreases by 0.292% (percent) and the shear strength of the nut and bolt decreases by 30%. According to the SEM examination, the density of the River markings, sharp edges, holes and sharp edges increased from Sections 1 to 3, which supports the findings mentioned above.

Hence, this work enlightens the aspects causing time lag during the 3D printing in MJP. It causes variation in the dimensional deviation, surface properties and mechanical properties of the fabricated part, which needs to be explored.

The purpose of this study is to investigate the characteristic and function of oxide film formed on grinding wheel in electrolytic in-process dressing (ELID) precision grinding and improve the quality of ELID grinding.

Dynamic film forming experiments were carried out with a simulation device close to the actual processing conditions. Then, the ELID grinding experiments of bearing rings were performed using grinding wheels with good film forming effect. The experiment was designed by quadratic regression general rotation combination method. The influence of grinding depth, electrolytic voltage, duty cycle and grinding wheel linear speed on grinding effect is analyzed.

A mathematical model for the formation rate of oxide film was established. The experiments show that the composition of grinding wheel and grinding fluid, as well as the electrical parameters, influence the film forming effect. Thus, the oxide film plays an important role in ELID grinding.

This study provides a reference for the design and selection of grinding wheel and grinding fluid and the setting of process parameters in ELID grinding.

The purpose of this paper is to build a new deployable antenna with folded scissors ribs and to evaluate the reasonable characteristics of this new structure.

Based on the TerrStar-1 satellite, virtual design and shapes forming are considered in this paper with the structure design of the new antenna. Considering the relaxation units in net surface, form-finding evaluation is used to build mathematical model and operate the optimization algorithm so that the design of the new antenna with folded scissors ribs is achieved. Simulations are carried out to verify the antenna proposed.

It is found that the antenna with folded scissors ribs can be developed smoothly in the space.

The proposed the antenna with folded scissors ribs can be considered as a fall-back alternative for large antenna, with a diameter of over 10 m in the space, or is seen as another option for the system with a simple rigid structure.

Different from traditional antenna, it provides a valuable reference for the further research of large deployable antenna in space. The antenna in this paper is able to develop more than 30 m of diameter. Meanwhile, the surface density and the natural frequency and the root-mean-square error in surface are superior to those of the traditional antenna.

The purpose of this paper is to study the functionality of additively manufactured (AM) parts, mainly depending on their dimensional accuracy and surface finish. However, the products manufactured using AM usually suffer from defects like roughness or uneven surfaces. This paper discusses the various surface quality improvement techniques, including how to reduce surface defects, surface roughness and dimensional accuracy of AM parts.

There are many different types of popular AM methods. Unfortunately, these AM methods are susceptible to different kinds of surface defects in the product. As a result, pre- and postprocessing efforts and control of various AM process parameters are needed to improve the surface quality and reduce surface roughness.

In this paper, the various surface quality improvement methods are categorized based on the type of materials, working principles of AM and types of finishing processes. They have been divided into chemical, thermal, mechanical and hybrid-based categories.

The review has evaluated the possibility of various surface finishing methods for enhancing the surface quality of AM parts. It has also discussed the research perspective of these methods for surface finishing of AM parts at micro- to nanolevel surface roughness and better dimensional accuracy.

This paper represents a comprehensive review of surface quality improvement methods for both metals and polymer-based AM parts.

This paper aims to present an optimal prototyping technology for the manufacture of occlusal splints.

To carry out this study, a comparative technique was used to analyze models obtained by different prototyping techniques. Subsequently, further tests were carried out with respect to the manufacturing of splints by means of thermoforming in a vacuum. This involved an analysis of the most important variables such as prototype material, geometric accuracy, surface finish and costs.

It was found that there is a group of prototyping technologies that are suitable for the manufacture of the models used in the thermoforming of correction splints, the most appropriate technologies being based on ink jet printing (IJP-Objet), ultraviolet photo polymerization and fused deposition modelling due to the fact that they offer an optimal relationship between the cost and the quality of the model required for thermoforming.

The application of rapid prototyping techniques in medicine makes the production of physical models from three-dimensional medical image processing and their subsequent use in different specialties possible. It also makes preoperative planning processes, the production of prostheses and the preparation of surgical templates possible, thereby offering a higher quality of diagnosis, safer surgery and cost and time savings compared to conventional manufacturing technologies.

This paper suggests that there exists a group of prototyping technologies for the manufacture of splints that offer advantages over existing technologies. The results also suggest that, in many cases, the most expensive technology is not the most appropriate: there are other options that provide an optimal model in terms of the cost and the quality needed for thermoforming.

This paper aims to develop a new magnetorheological polishing (MRP) device with roller and investigate the polishing mechanism of MRP fluids using this new device.

The principle of MRP process with roller is discussed, and then the structure of the polishing device is designed in detail. The polishing experiments of K9 glass are carried out using MRP device with roller.

A series of tests are performed to evaluate the effect of the excitation gaps, working gap and polishing time on the polishing characteristics, and the optimized polishing parameters can be obtained. The surface roughness Ra of the sample is reduced from 359 to 38 nm under optimized polishing parameters.

MRP method with roller is proposed in this paper, and the MRP device with roller can reduce the surface roughness Ra significantly. After being polished, the circular ring-shaped polishing belt disappears on the workpiece surface, which means it has great potential for polishing.