Key Engineering Materials Vols. 392-394

Abstract: In this paper, the characteristics and general laws of cutting complex curved surface by wire electrical discharge machining (WEDM) system are studied. Based on analysis of motion parameters the universal mathematical model of polar coordinates is derived. Moreover, the simulation of WEDM system is introduced, which is carried out by using language Visual C++ and the three dimensional graph software OpenGL.This simulation method is helpful in improving machining quality and productivity of complex curved surfaces, and is fundation for establishing CAD/CAPP/CAM technology in WEDM.

Abstract: Cutting force model for flat end milling and dynamic model of cam milling system were established based on the analysis of machining system for parallel indexing cam contour milling. Solution for dynamic performance of this kind of milling system has been introduced. A system, consisting of NC milling machine SK1632K3, tooling and workpiece, has been taken as example to analyze how cutting speed, feeding, or processing redundancy influence the dynamic performance of machining system. Furthermore, milling error of cam contour has been evaluated corresponding to different machining parameters. Simulation and analysis results are very close to practical manufacturing situation.

Abstract: Based on the theoretical analysis of forming shoulder used in fill-and-seal packaging machine, this paper presented the 2-D and 3-D mathematical models of offset bending curve jointing the vertical tube and shoulder parts. According to the technology widely used in the manufacturers, the theoretical basis was provided for preparing the rough parts to make the shoulders. Furthermore, a new method using test tube was proposed to check the shape curve and locate the shoulder parts before welding. Transformed from 3-D offset bending curve, the 2-D cutting data of test tube was also provided for practical use.

Abstract: A micro-EDM equipment which can fabricate three-dimensional micro-structures is developed. A method of electrode wear compensation on-line which is very important to micro 3D structures machined by micro-EDM is presented. In this method, the wear of electrode can be predicted by the statistics law of open rate of discharge status, therefore, its precise model which is very difficult to build as well as the special CAD/CAM system is hardly necessary. At the same time, the micro-EDM CAD/CAM technology which applies the universal CAD/CAM software for milling is also researched and experienced on Unigraphics (UG). At last, micro 3D structures, a micro hemisphere with diameter ∅150+m and a micro 3D beam which is very popular in MEMS, are machined on silicon wafer by this way, which proves the wide useful of this method and the promising application in MEMS.

Abstract: Using environment-friendly cutting fluid in the process of metal cutting is one of the valid paths to carry out the green manufacturing. Using metacrylic acid ester, castor oil and boride as the main raw materials, a new type of environment-friendly water-base cutting fluid had been obtained. The main components of this cutting fluid are some kind of high molecular polymer and some kind of B-containing castor oil EP agents. The test results show that the cutting fluid has good stability, antirust property and biodegradability. The maximal non-chucking load value (PB) of the cutting fluid, whose consistency is 5%, can be 1068N. In the comparison with dry cutting, cutting force using environment-friendly cutting fluid is reduced by 23% in a certain condition. Using this cutting fluid can raise stock-removing efficiency and cutting quality, and extend the service life of cutting-tool. And this cutting fluid is harmless to operators and free from pollution to the environment. Expansion and application of the environment-friendly cutting fluid are advantageous to promote the development of the green manufacturing.

Abstract: Management of fixture design knowledge is vital for improving product quality and reducing product lead time, but there is no efficient and effective mechanism in current computer-aided fixture design systems to integrate fixture design process, to share design resource as well as acquisition and reuse knowledge. Ontology is increasingly seen as a key technology for enabling semantics-driven knowledge processing. On the background of a architecture of fixture design system based on knowledge introduced in the paper, we presented and expatiated a fixture design knowledge acquisition and reuse technology based on ontology, which embeds ontology in current computer-aided fixture design based on knowledge. Finally, the related case study was given.

Abstract: This paper studies the effect of spool valve diametral clearance of electro-hydraulic servo valve on orifice discharge characteristic. To ensure that the freely sliding between spool and sleeve, there must be given diametral clearance between spool and sleeve, which will have an impact on valve orifice discharge characteristic, this paper first individually sets up a 3D models of clearance from 0 to 5 μm, opening value from 0 to 40 μm, then calculates each model’s discharge on the condition that valve orifice’s inlet and outlet differential pressure is constant, finally according to the result of the discharge plots the diametral clearance curve of spool valve. The quantitative numerical relationship of diametral clearance and spool valve characteristic index is given after doing the analysis, Finally, an experimental verification of the simulation results is to be done to prove the simulation results are correct and reliable. The research of this paper provides the basic guidelines for spool valve designing and testing.

Abstract: Laminated templates electro-deposition is an original manufacturing technology that is aimed at micro-scale metallic structures fabrication. Based on the discrete piling-up principal and electrodepositing method, it realizes a manufacturing simplification from the traditional machining to the repetition of template-assisted planar deposition in forming a three-dimensional complicated object. The ability to control the deposit surface nouniformity is a key to successful implementation for each planar depositing. Profile geometry and current configuration are alternated in experiment and thought as the major factors influencing deposit surface roughening. The results show that the surface of the deposits obtained by pulse electroforming has better performance in deposit thickness distribution and properties of the deposits. Optimized parameters have been obtained from the preliminary experiments in which 0.3millimeters-thick epoxy templates and 4~6A/dm2 current density were used at 40+ and a bulk of copper parts, section size 30mm×30mm and 7mm thick were produced and tested for their mechanical performance.

Abstract: Remote monitoring is an important technical way to assure the key equipment to run properly and safely. In the paper, a remote monitoring system based on GPRS wireless communication was developed for large-scale equipments. The architecture of the system was given. The key techniques of the system design, including the remote data transmission, remote monitoring and fault diagnosis techniques were analyzed. Furthermore, the hardware and software design of Data Transmission Unit (DTU) was introduced in detail. And the functional modules of the remote monitoring service system were presented. The system provides an effective way to realize remote monitoring and fault diagnosis for large-scale equipments.

Abstract: Inherent uncertainties always exist in the positioning picking manipulators in complex environment, modeling and simulation of positioning. The manipulators were discussed based on binocular stereo vision in virtual environment (VE). Based on stereo vision, a method how virtual manipulators locate picking object by human-computer interaction (HCI) was proposed. The data input from vision were mapped to virtual picking manipulators so that it could enable the positioning and simulation with route and events-driven mechanism. The positioning experimental platform in VE consists of hardware of CCD stereo vision and simulation software. The visualized simulation system was exploited by EON SDK. The simulation of manipulator’s positioning was realized in VE by the platform. This method can be used for virtual robot to locate objects’ long-distance positioning in complex environment.