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This paper aims to comprehensively achieve the requirements of high assembly precision and low cost, a precision-cost model of assembly based on three-dimensional (3D) tolerance is established in this paper.

The assembly precision is related to the tolerance of parts and the deformation of matching surfaces under load. In this paper, the small displacement torsor (SDT) theory is first utilized to analyze the manufacturing tolerances of parts and the assembly deformation deviation of matching surface. In the meanwhile, the extracting method of SDT parameters is proposed and the assembly precision calculation model based on the 3D tolerance is established. Second, an integrated optimization model based on the machining cost, assembly cost (mapping the deviation domain to the SDT domain) and quality loss cost is built. Finally, the practicability of the precision-cost model is verified by optimizing the horizontal machining center.

The assembly deviation has a great influence on cost fluctuation. By setting the optimization objective to maximize the assembly precision, the optimal total cost is CNY 72.77, decreasing by 16.83 per cent from the initial value, which meets economical requirements. Meanwhile, the upper bound of each processing tolerance is close to the maximum value of 0.01 mm, indicating that the load deformation can be offset by appropriately increasing the upper bound of the tolerance, but it is necessary to strictly restrict the manufacturing tolerances of lower parts in a reasonable range.

In this paper, a 3D deviation precision-cost model of assembly is established, which can describe the assembly precision more accurately and achieve a lower cost compared with the assembly precision model based on rigid parts.

This article is a review of research on the theme of Soviet product quality and Soviet state standards. The first section surveys previous research by Western scholars on the topic of Soviet product quality, paying particular attention to their sources of information. This is followed by a discussion of the availability of Soviet state standards as data sources on Soviet product quality. The third section of the article consists of a case study of the use of Soviet state standards to assess product quality, paying particular attention to machine tools. The article concludes with a discussion of the results and suggests avenues for further research.

The purpose of this paper is to verify the feasibility and reliability of mineral casting applied in high-precision printed circuit board (PCB) drilling machine. The mechanical properties of machine frame are quantified to provide a solution for machine tool industry to seek a perfect substance competing with classic materials such as cast iron and granite.

The optimal design of machine frame is performed via the CAD system combined with finite element analysis (FEA). The mechanical properties of the frame elements are evaluated by a series of mechanical experiments: static performance is quantified by flatness tests, dynamic behavior is estimated by experimental and numerical models, respectively. Meanwhile, the performance of the frame element with traditional materials is examined experimentally.

Mineral casting parts can be successfully applied to PCB drilling machine to meet high accuracy requirements. The characteristic of mineral casing gives the most possibilities in structural design. The frame parts show good static/dynamic behaviors by structural optimization processes. Especially, the machine frame with mineral casting gains a great weight reduction compared with traditional materials.

The application of mineral casting in PCB drilling machine offers greater design flexibility and innovative system solutions. The combination of FEA is convincing to achieve optimal structure and ideal weight to maximize the economic and technical benefits. Moreover, lightweight design of machine structural components achieves not only higher kinematic/dynamic precision but also considerable cost reduction.

The traditional precision design only takes the influence of geometric tolerance of the parts and does not involve the load deformation in the assembly process. This paper aims to analyze the influence mechanism of flexible parts deformation on the geometric precision, and then to ensure the reliability and stability of the mechanical system.

Firstly, this paper adopts the N-GPS to analyze the influence mechanism of flexible parts deformation on the geometric precision and constructs a coupling 3D tolerance mathematical model of the geometric tolerance and the load deformation deviation based on the SDT theory, homogeneous coordinate transformation theory and surface authentication idea. Secondly, the least square method is used to fit the deformation surface of the mating surface under load so as to complete the conversion from the non-ideal element to the ideal element.

This paper takes the horizontal machining center as a case to obtain the deformation information of the mating surface under the self-weight load. The results show that the deformation deviation of the parts has the trend of transmission and accumulation under the load. The terminal deformation cumulative amount of the system is up to –0.0249 mm, which indicated that the influence of parts deformation on the mechanical system precision cannot be ignored.

This paper establishes a comprehensive 3D tolerance mathematical model, which comprehensively considers the effect of the dimensional tolerance, geometric tolerance and load deformation deviation. By this way, the assembly precision of mechanical system can be accurately predicted.

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 purpose of this study is to investigate an effective method to manufacture propellers.

The investment casting process and injection molding process have been applied separately to the rapid prototyping/rapid tooling (RP/RT) to obtain metal (Al‐Si alloy) propellers and plastic (Acrylonitrile butadiene styrene – ABS) propellers. The two different manufacturing processes were compared following the same master model (MM). The Moldflow software is used to optimize the experimental parameters of the molding. Furthermore, a gypsum type of powder is used to produce the RP MM of the propeller according to the Pro‐E software. The RP MM then is filled with a metallic resin material (at room temperature) to obtain a wax mold. Then, this wax mold was coating by dipping the ZrO₂ slurry to improve heat resistant ability, and following solidification, and then filled with metal alloy to obtain metal (Al‐Si alloy) propellers. Another process, the RP MM by dipping the ZrO₂ slurry to increase the heat resistance and then is filled with aluminum alloy and an injection mold can be obtained, the plastic (ABS) propellers can be duplicated. To ensure the precision of dimension and improves the surface roughness for the RT (metallic resin mold and aluminum alloy mold), the contour of the duplicated molds were milling with the high‐speed CNC manufacturing program.

The advantage of this process is that combining the RP/RT system with the high‐speed CNC machining center enables easy production of injection molds.

This process provides engineers with a quick way to fabricate parts and modify the designs. This study demonstrates that this process provides a practical way to fabricate parts and saves the cost and time which increases market competition. The molds with high precision and good surface roughness were duplicated by the rapid‐prototype technique. Furthermore, this investigation demonstrates that: if the product contains special shapes? The material requires a large amount of cutting? or In the case of expensive and hard to machine materials, the proposed process is the best choice to duplicate cost‐effective mold.

The purpose of this paper is to describe the development of a novel mobile monitoring and control (MC) framework with active-push and plug-and-play capabilities. This proposed framework is particularly designed to addresses the shortcomings of the traditional factory MC systems in sharing information over the internet, protecting the system security, delivering warning messages, and deploying monitoring points.

By leveraging web service technology, mobile devices, and wireless communication, this paper describes the methodology and approach for designing a MC server, a wireless monitoring module (WMM), an intelligent v-Machine, two active-push mechanisms, a pocket PC application, and a smart phone application.

The designed WMM enables the monitoring points to be deployed in a mobile manner. The proposed mobile MC framework (MMCF) can timely detect abnormalities of appliances and equipment and turn off appliances in dangerous situations through WMM. It can also instantly deliver various warning contents to the mobile devices carried by the responsible persons. The v-Machine is built based on virtual metrology (VM) technology and can predict production precision of machined workpieces.

With the successful design and testing of the novel MMCF, this framework can obviously be used for many more applications and developments.

The authors' implement a factory MC system based on the proposed framework and conduct various integration tests on two electric appliances and a practical CNC machine tool in a factory. Testing results shows that the factory MC system works smoothly according the design goals and can overcome the shortcomings of traditional factory MC systems. The MC system also presents good performances, instantly delivering warning contents with a size ranging from 1K bytes to 10M bytes to the users within few seconds.

The proposed MMCF exploits various automation technologies to detect equipment's abnormalities, reduce the rate of product defects caused by human errors, reinforce security, prevent accidents, and ensure the safety of operations.

The proposed MMCF can effectively promote existing factory MC systems to achieve the merits of mobile MC, which is a unique contribution of this work, compared to previous studies. The results of this study can be applied to a variety of industrial automation applications, including factory automation and assembly automation.

Novel nanomaterials and nano-devices require further functional aspects that can be designed and supported using new nanomanipulation techniques allowing specific functions at the design phase. The nano-manipulator becomes a key instrument for technology bridging sub-nano to mesoscale. The integration of various operations in nano-devices requires sub-nanometer precision and highly stable manipulator. This paper aims to review various design concepts of recent nanomanipulators, their motion characteristics, basic functions, imagine and automation with control techniques for the sake of establishing new design features based on recent requirements.

The paper reviews various existing nanomanipulators, their motion characteristics, basic functions, imagine and automation with control techniques. This will support precision machine design methodology and robotics principles.

The availability of a nano-precision instrument with integrated functions has proved to be extremely helpful in addressing various fundamental problems in science and engineering such as exploring, understanding, modeling and testing nano-machining process; exact construction of nano-structure arrays; and inspection of devices with complex features.

New functional specifications have emerged from this review to support the design and make of new advanced nanomanipulators with more features availability to support manipulation within the same reference datum needed for research and education.

Laser calibration is becoming almost standard practice for machine tools aspiring to high levels of accuracy, and the Hewlett Packard system is now widely used by machine tool builders. But Ernest Drake from the company's headquarters in California was in this country recently arguing that many other companies could benefit from the laser's accuracy.