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The ruled surface of impeller is widely used in the industry of automobile, shipbuilding, aerospace and aeronautics. Researches on the manufacture of blade possess general meaning. The importance of their performance in the certain field and the non-replace ability of their functions in the specified mechanical systems have resulted in that the technology of manufacturing and measurement for ruled surfaces has been a critical research project in the field of dimensional manufacturing and measurements. With the rapid development of the modern science and technology, complex ruled surfaces are employed more and more widely, but their tolerances become narrower and narrower. The common impeller surfaces represented by NURBS are given and then curve and surface interpolation algorithm represented by NURBS are presented. These provide theoretical foundation for NC machining programming of impeller surface. Principals of normal offset curve and inclined offset surface are used to simplify the model. The NC milling method of divide area is presented to raise machining efficiency and to improve quality of machined surface. The machining efficiency is important in line property of rule surface, flank milling rule surface with end-milling, improve surface quality and cutter efficiency. This paper presents a calculate method to generate five-axis flank milling NC code of divide area in the blade of compressor with Vericut simulating the five-axis flank milling NC code and measurement the result of processing that verification the precision of five-axis flank milling. This paper also simulates four-axis machining for comparing cutting efficiency between five-axis machining and four-axis machining and the status of both the great differences in processing efficiency.

Roundness and spindle error motion measurements are two fundamental issues in the geometrical measuring techniques. Most of the fixture with rotating cylindrical shaft, cylinder defined by the minimum circumscribed axis, can be obtained the minimum circumscribed rotation surface high-precision axis. Generally, a more accurate measurement points, can result in a more accurate cylindrical shaft, but the longer the time of the calculation time. In this paper, the drawing method can handle a large number of measurement data to avoid lengthy and complicated calculations, and can quickly obtain the minimum circumscribed cylindrical axis precise location, deviation and cylindrical radius and tolerance. This article is the use of the minimum circumscribed cylinder theoretical approach with computer drawing ways. Comparison is relatively quick and easy. The actual display of the results, which can be easily, obtained the position, skew and deviation of the spindle. This paper will be established a cylindrical outer edge quality assessment model and provided a basis for the cylindrical outer edge quality assessment. This paper for seeking the axis of cylindrical shank is based on minimum circumscribed cylindrical theory with computer drawing method and instances for verification. The computer drawing method can be determined spindle eccentric angle and the distance of deviation, to provide a reliable model for the evaluation of rotary spindle, the mode established by the paper at the same time applicable to any other rotating spindle error evaluation.

Machining accuracy of thin-walled parts is easily affected by clamping and cutting deformation due to its poor stiffness. In this paper, synchronous optimization method of clamping force and cutting parameters is presented based on GA and FEM. The optimization objective is to minimize the maximum deformation and to improve the machining efficiency. GA is used to optimize cutting parameters and clamping force, and FEM is used to predict the machining deformation of the thin-walled workpiece. Finally, taking a titanium alloy thin-walled part with irregular shape as an example, the optimal clamping force and cutting parameters at every cutting position are obtained to demonstrate the feasibility of the method.

Large gantry machining centers are used for machining of products in almost all industry. To raise the design and production efficiency of machining centers, an integrated method of fast design and analysis is proposed in this paper. Firstly, large components unit structures are decomposed and extracted based on functions and structures. Then, after conducting fast analysis using APDL programming, a method of Comprehensive Evaluation is employed to optimal select the design schemes. Finally, the column of large gantry machining center QLMT6300 is taken as example to illustrate the validity of the method presented.

The autoclave moulding process of composites is characterized by reentrance, capacity and time constraints. Its scheduling directly affects productivity and production cycle of composites. Scheduling methods in the existing literature can't meet the requirements of its scheduling optimization. Aiming at improving utilization and reducing energy consumption of autoclave, based on the Theory of Constraints, a heuristic algorithm considering the capacity and time constraints is proposed to solve the scheduling problem, and priority scheduling rules are established. The studying of a case shows the effectiveness of the algorithm.

An approach to optimize the cutting parameters based on Particle Swarm Algorithm(PSO) and Finite Element Method(FEA) was proposed. A cutting parameters optimization model was established whose design variables are the cutting parameters and objective function is to minimize the maximum deformation. PSO was used to optimize the cutting parameters and FEA was utilized to predict the machining deformation of the thin-walled workpiece. Finally, the entire technique was demonstrated in a case study. The simulation and experimental results show that the approach can be further employed into the practical machining situation.

The crossbeam is an important part in the gantry machining center which greatly affects the machining accuracy. Four kinds of crossbeam structure for the large machining center were designed and their static and dynamic characteristics were analyzed. The optimal crossbeam structure was selected by the comprehensive performance evaluation method. Then the thicknesses of rib plates in the crossbeam were defined as the optimization parameters after conducting the sensitivity analysis. The first four natural frequencies were defined as the objective functions and the static performance and the mass were defined as the constraint conditions. The optimal sizes of the rib plates in the crossbeam were obtained by the optimization analysis. Finally the feasibility of the result was demonstrated by the simulation. The result indicated that with the mass increased only by 0.18%, the first four natural frequencies of the optimal crossbeam were increased by 19.56%, 19.45%, 19.84%, 17.05%.

Processing precision of numerical control machine tool is decided by static rigidity and dynamic rigidity of spindle to a great extent. 3- D model of numerical control machine tool was established by using parametric modeling and virtual assembly function of Solidworks. Simultaneously, simulation and Experiment study of the spindle static rigidity was carried out, and practicability of the simulation analysis method was proved. The result indicates that the biggest deformation appears in the front of spindle. The static rigidity of spindle can been enhanced greatly by enhancing three carriage-feed system’s static rigidity of machine tool. The simulation for the dynamic rigidity of spindle indicates that the dynamic rigidity of spindle is uniformly distributed and resonance can be avoided effectively by the spindle when working.

Designing a flexible fixture is much more complicated. In this paper a collaborative environment was introduced for flexible fixture design. The tasks involved in fixture design are analyzed and decomposed into five subtasks, which are assigned to workgroups by a project manager. The workgroups can be distributed in different departments or in different locations geographically. The framework of collaborate design environment is constructed. Each workgroup is responsible to a certain job. However, the information needed for flexible fixture design is shared among these workgroups. The information exchanging and management in the environment are expressed with a block diagram. Finally, an example of flexible fixture for manufacturing a thin-walled workpiece is employed to illustrate the efficiency of the collaborative environment.

Thin-walled workpiece is prone to produce deformation in the process of machining because of cutting and clamping forces. In this paper, a model of cutting parameters optimization is proposed to control the deflection. The influence of deflection on nominal milling depth is taken into account and the machining deflection is computed by iterative method. Based on the optimization model, a prototype system is developed to optimize the cutting parameters for a thin-walled workpiece with the genetic algorithm and finite element method. Finally, a simulation example is used to demonstrate the feasibility of the cutting parameters optimization method. The simulation result can be further employed into practical machining situation.

Having first defined the helical angle as the angle between the cutting edge and the axis of rotation of the cutter, this paper then presents design models for producing the cutting edge and groove of a ball-end cutter with concave-arc generator. The relative feed speeds of the grinding wheel in the radial and axial directions during NC machining of the cutter are derived based upon a given speed of rotation. The feed speed of the grinding wheel in the radial direction is modified according to the cross section of the groove that passes through the center of the cutter sphere. The paper presents a method for manufacturing a concave-arc ball-end (CABE) cutter using a 2-axis NC machine. The models that are used to calculate the actual obtained groove and the computer simulation method are also included. To further enhance the accuracy of the mathematical models, a compensatory machining process that eliminates residual profile on the revolving surface is presented. This paper provides a valuable reference for the design and machining of this cutter type.

This paper presents models for defining the minimum circumscribed cylinder (MCC) of the cutter shank, the minimum circumscribed circular-arc-type revolving surface (MCCRS) and the minimum circumscribed corner arc revolving surface (MCCARS) with a spiral groove. A systematic modeling procedure is presented for the assessment of the contour quality of the circular-arc end milling (CAEM) cutters with a cylindrical shank. The axis of the MCC of the cylindrical shank of a revolving cutter with a circular-arc generator curve and a corner radius is taken as the datum line. The profile tolerances and errors are estimated. The presented models are all illustrated and verified by example. This approach can be generalized to a cutter with more than two circular arcs in its shape profile. The paper provides a valuable reference for the evaluation of the actual contour quality of this type of revolving cutter.

The paper presents a systematic manufacturing model for producing the circular-arc ball-end milling (CABEM) cutter. Having first defined the helical angle as the angle between the cutting edge and the axis of rotation of the cutter, the geometric shapes of helical grooves and cutting edge profiles are analytically derived. The feed speed of the grinding wheel in the radial direction is modified according to the cross-section of the groove that passes through the centre of the cutter sphere. The models that are used to calculate the actually obtained groove, and the method of computer simulation are also included. To further enhance the accuracy of the mathematical models, a compensatory machining process, which eliminates residual profile on the revolving surface, is also presented.

The toroid-shaped helical cutter with an involute generator is a precision tool used in the machining of involute helical gears. Taking the axis of the minimum circumscribed cylinder of the measured points on the cylinder shank as the datum axis, this paper provides models of the minimum circumscribed involute revolving surface and the minimum circumscribed toroid-shaped revolving surface. This paper also presents models for evaluating the contour quality of a toroid-shaped cutter with an involute generator. The validity and accuracy of these models are confirmed by worked examples.

Outer cycloid gears are used widely in many instruments and machines. The outer cycloid slotting cutter is an important cutting tool used in the manufacturing of this type of gear. In the process of design, the ideal outer cycloid cutter is one where a cylindrical surface takes the tooth profile of the outer cycloid as the directrix. However, during the manufacturing process, it is used as a cutter and therefore a cutting edge is required. As a result, it will be seen that the processes of design and usage of the outer cycloid cutter are not the same. The range of the qualified length of tooth is deduced in this paper by using the mid-point and mid-line method. This paper also presents the associated outer cycloid slotting cutter design and manufacturing models so that the modelling accuracy and the necessary relief angles of the top cutting edge and side cutting edge can be ensured. This paper is intended as a reference to be used in the manufacture and application of this type of slotting cutter.

ESD/latchup are often two contradicting variables during IC reliability development. Trade-off between the two must be properly adjusted to realize ESD/latchup robustness of IC products. A case study on SERIAL Input/Output (I/O) IC’s is reported here to reveal this ESD/latchup optimization issue. SERIAL I/O IC features a special clamping property to wake up PC’s during system standby situation. Along with high voltage operation, Input/Output (I/O) protection design of this IC becomes one of the most challenging tasks in the product reliability development. In the initial development phase, ignorance of latchup susceptibility resulted in severe Electrical Overstress (EOS) damage during latchup tests, and also gave a false over estimate of ESD protection threshold through parasitic latchup paths. The latchup origin is an output PMOS and floating-well ESD triggering NMOS beside the PMOS, and the main fatal link is this high-voltage (HV) NMOS connecting to a bi-directional SCR cell. This fatal link led to totally five latchup sites and three latchup paths clarified through careful and intensive FIB failure analysis, while this powerful SCR ESD device without appropriate triggering mechanism still could not provide sufficient product-level ESD hardness. Owing to there being no design window between ESD and latchup, the original several protection schemes were all abandoned. Using this bi-directional SCR ESD cell and proper triggering PNP bipolar transistors, a new I/O protection circuit could sustain at least ESD/HBM 4 kV and latchup triggering current 150 mA tests, thus accomplish the best optimization of ESD/latchup robustness.

This paper presents a systematic modelling procedure for assessing the profile quality of concave-arc ball-end (CABE) milling cutters with a cylindrical shank. CABE milling cutters are widely used in three-axis numerical control (NC) machines for producing dies and moulds of complicated surface features. Evaluation of the contour quality of the CABE milling cutter is crucial in enhancing machining accuracy and efficiency. In order adequately to describe the shape of the clamped cutter, the centre-line axis of the minimum circumscribed cylinder of the cylinder shank is taken as the referenced datum axis. The minimum circumscribed concave-arc revolving surface and the minimum circumscribed spherical surface are carefully derived in sequence. The profile errors and tolerances are estimated. The quality of the CABE milling cutter is assured by using the proposed modelling procedure, and several numerical examples are presented to illustrate its effectiveness. The results indicate that the present method is feasible and can be extended to enhance the quality of various revolving cutters.

The paper presents a geometric modelling approach for the precision design and NC machining of a concave-arc ball-end milling (CABEM) cutter which is an important tool for mould-making industries. This paper presents systematic models of the cutting edge, helical groove, and grinding wheel design for the NC machining of a CABEM cutter. Both the normal to the revolving axis and the tangent to the groove, are used to derive the required precision sectional profiles of the grinding wheel. In compliance with the maximal sectional radius of the cutter, the profile of the groove section and both the radial and axial cutting speeds of the grinding wheel are computed in sequence. Using the computer simulation results of the groove actually obtained, this paper proposes a method to resolve the problems of the residual revolving surface and the narrow cutting edge strip. This paper is intended to serve as a reference for the design and NC machining of cutters of this type.

This paper presents models for evaluating the contour quality of a toroidal cutter with a concave-arc generator and a cylindrical shank. Taking the axis of the minimum circumscribed cylinder of measured data on the cutter shank as the datum axis, models are developed to investigate the minimum circumscribed concave-arc revolving surface and the minimum circumscribed toroidal revolving surface. Illustrative examples are given to verify the validity of these models. This paper provides a reference for evaluating the contour quality of this type of revolving cutter.

The paper presents a systematic modelling approach for precision design and numerical control (NC) machining of the tapered ball-end milling (TBEM) cutter that has emerged as a powerful tool for mould-making industries. The major contribution of this work is to produce a complete cutting edge that was conventionally neglected or oversimplified near the ending portion interfacing with the tapered ball end. In order to comply suitably with the requirement for a specific rotating speed, both radial and axial cutting speeds are carefully derived by using a given helical angle defined as the angle between the cutting edge and the revolving axis. Both projected profiles, one normal to the revolving axis and the other tangential to the groove, are used to produce precision sectional profiles of the grinding wheel. In compliance with maximal sectional radius of the taper, the profile of the groove section and the feeding speed of the grinding wheel are computed in sequence. By means of a two-axis NC machine, the shape of the TBEM cutter that possesses a nearly constant helical angle can be systematically designed and produced. With a slightly remedial grinding procedure at the ball end, the dimensional accuracy of the groove and the cutting edge of the TBEM cutter can be well controlled.

This paper presents mathematical models of the cutting edge and helical groove, and the design of the grinding wheels for use in the NC machining of toroid-shaped cutters with a concave-arc generator. According to computer simulation results of the groove actually obtained, the problems of residual profile errors on the groove surface and the cutting edge curve are presented, and rectification action is proposed. This paper provides a reference for the design and NC machining of this type of cutter.

This paper introduces the differences in quality evaluation for the sampling inspection of drills with taper or cylindrical shanks. For a drill with a taper shank, the datum axis is taken to be the axis of the minimum circumscribed cone, whereas for a drill with a cylindrical shank, the datum axis is taken to be the axis of the minimum circumscribed cylinder. The features that are common to both drill types are the definition of the minimum circumscribed cylinder of the cylinder part with helical grooves and the minimum circumscribed univalent hyperboloid based upon the datum axes given above. This paper presents all the necessary supporting models, illustrated and verified by examples, for the evaluation of actual contour quality for these two drill types which are comprised of compound surfaces.

The paper presents a comprehensive manufacturing model that can be used to produce a concave cone-end milling (CCEM) cutter on a two-axis NC machine. A CCEM cutter possesses many distinct features that are superior in many cases to the traditional flat-end milling cutter for producing parts with multiple sculptured surfaces. Based upon the given design parameters and criteria, the equation of the helical flute groove and the curve of the cutting edge at the end of the helical flute are derived and presented. By using an inverse problemsolving technique, the sectional profile of the grinding wheel, the tool compensation for machining, and the feedrate of both NC axes are consequently obtained. The design results are compared with the measured data obtained from the NC produced CCEM cutter. The satisfactory comparative verification indicates that the tool design and manufacturing model presented in this paper is theoretically sound and it can be automated easily. The proposed method is widely applicable for the mass production of various high-efficiency milling cutters.