Micro-electrical discharge machining has been an important technology which can manufacture mesoscopic characteristic precisely on conductive materials.However,its machining efficiency is too low to meet current manufacturing requirement.The main reasons include two aspects:durative tool electrode wear results in tool electrode grinding frequently;Match between pulse energy and machining quality results in the selection limitation of pulse energy.Therefore,it aims at efficiency enhancement for micro-electrical discharge machining.Parallel stage structure design,alternating pulse power supply,multi-mode wire electrical discharge grinding,multi-functional spindle design,multi-technics combination,etc.Then,experiments have been done and the results show that the application of above measurements will be beneficial to enhance micro machining efficiency.

Aiming at the research on relationships between the train axle box parameters,the definition of top-down design,boundary conditions,performance index and design parameters are given.By using the method of House of Quality (HoQ) theory and complex network theory,the main parameters in boundary conditions from higher values of out-degree index of the spring species,weight,vehicle suspension and other parameters are gained.Car-body weight,free vibration,primary suspension and other parameters which have higher values of out-in-degree index is the most considerable performance indexes.And the damper cylinder volume,material,spring center horizontal span and other parameters which have higher values of in-degree index are the main design parameters.The main design parameters can be obtained based on the uniform definition of index formula for out degree and in degree.

Electrochemical pattern transfer machining is a kind of methods of channel shaping,in which it’s hard to monitor the change of channel profile and shaping law.In this work,a new approach by employing computer simulation method was applied to simulate the channel forming processing.Mathematical model based on electric field was built and finite element method was selected to analyze and compute the corrosion process of channel by using the time-dependent APDL language based on electrochemical machining shaping theory.The comparison denotes that simulation date deviates from experimental in less than 18% in depth and 6% in width of channel.Accordingly the good agreement between theory and experimental data verified the validation of the computer simulation of the channel machining in Electrochemical Machining (ECM).

To design and analyze the butt joint ultrasonic fatigue specimen of MB8 wrought magnesium alloy,and to study the influence of weld seam size and resonance length on natural frequency of the specimen.The size of ultrasonic fatigue specimen without weld seam was calculated by analytic method which provides the preliminary reference size for the sample of the butt joint.In the finite element software,the sample of the weld joint was simulated and analyzed by establishing solid model,meshing and modal analysis.The influence of the weld size on the natural frequency of the sample was obtained by changing the weld seam size.The influence of the resonance length on the natural frequency of the sample was acquired by altering the resonance length.According to this rule,the sample size is optimized,so that the natural frequency of the butt joint sample is close to 20kHz. The weld seam on ultrasonic fatigue will make the frequency of the specimen natural deviate from 20kHz.Increasing width and height of weld seam will lead to enlarge the natural frequency of specimen.When the height of the weld seam increases,the effect on the natural frequency of specimen becomes weakened.When the width of the weld seam increases,the effect of width on the natural frequency amplitude of specimen remains unchanged.The natural frequency of the sample will be 20.022kHz when the L₃ is adjusted to 17.4 mm.Therefore final size of MB8 wrought magnesium alloy butt joint ultrasonic fatigue specimen is as below:b₁ for 3mm,b₂ for 8mm,L₁ for 12.5mm,L₂ for 15mm,R₀ for 46.25mm,L₃ for 17.4mm.

The artificial measurement of elevator guide rails is labor intensity,low efficiency and low precision.In order to solve the problem,designed a set of elevator guide rails automatic measurement system based on binocular vision.The system consists of the hardware system and the software system.Aiming at the problems of low contrast and less feature points of the surface of the elevator guide rails,the laser grid is projected onto the surface of the workpiece,so that the surface can be determined with identifying characteristics.It uses improved RANSAC algorithm to extract the laser grid.And then it uses SURF algorithm to extract and match the image feature points,and calculates the spatial coordinates of the feature points based on the camera calibration result.Finally,it calculates the flatness,parallelism and perpendicularity of the elevator guide rails according to the spatial coordinates of the feature points.Experimental results show that the system is reasonable,good software stability and high efficiency.It improves the efficiency and accuracy of the measurement of elevator guide rails and has a very good practical value.

The fundamental of permanent magnet eddy braking is analyzed and the math model about the parameters of braking force,the number of the magnet pole pair,the thickness and bottom diameter of the magnet and so on is developed on the basis of electromagnetic theory.Additionally,the results of math model and Ansoft Maxwell are analyzed to verify its correctness and the practicability.The influence mechanism of the number of the magnet pole pair,the thickness and bottom diameter of the magnet and so on to the braking force is explored to gain the characteristic relation among them.The dynamic model is developed according to the characteristic of bridge crane and design the parameter of the permanent magnet eddy current brake.At the last,the simulation of the dynamics is performed to provide the basis to the design of permanent magnet eddy current brake of the crane.

A two-stage classification method is proposed for engineering machinery spare parts aiming at the characteristics of randomness,diversity and complexity.In the first stage,the spare parts are divided into two categories according to the stability of the service spare demand time series.In the second stage,combined with the factors such as the value,service,time and other factors of the spare parts classification,the Rough Set (RS) theory and Self-Organizing Map (SOM) neural network are combined to design the RS-SOM clustering model.The index data are discretized by using fuzzy c-means clustering algorithm.Then the improved matrix algorithm is used to reduce the index set.In the kernel based SOM model,the training process is improved by introducing rough set theory.Finally,the clustering results of engineering machinery spare parts are obtained.Data experiments show that compared with the method of the ABC classification method and the traditional SOM clustering method,the classification result is better and it can provide a more reliable basis for the selection of the spare parts forecasting method and inventory strategy.

Because of the improvement of information level in a workshop,its traditonal inspection data can’t meet the demands of quality managenent.To solve this problem,a computer aided inspection plan system was built and was intergrated with manufacturing execution system.Part’s MBD model was used as the data source and the second development of UG software was used to extract these data.Meanwhile,an inspection domain ontology and knowledge base was built to reason the inspection instruments and inspection methods.

Studied a dynamics simulation analysis method for a rigid-flexible coupling system of quadruped robot.Established the flexible body model,quadruped robot rigid-flexible coupling dynamic model is established by ANSYS and ADAMS and analyzed the effect of elastic deformation simulation and rigid body simulation on the robot walking gait.In addition,analyze the robot walking in the process of stress and strain.Results show that the rigid-flexible coupling model and the actual situation more similar,more realistic reflection of the working performance of the robot,which provides an important basis for further gait planning,structure design and optimize of the quadruped robot.

In order to improve the efficiency of robot arm design and shorten the development cycle.First,a three-dimensional model of the robot arm with six-freedom was built in Solidworks software,then the model was imported into the kinematic and dynamic analysis software Adams to carry out the kinematic analysis,for veryfing the constraint of virtual prototype was correct.Then,through the interface modular part(Adams/Controls)of Matlab and Adams,the virtual prototype was imported into the Matlab,control system was established by Matlab/Simulink module,the imported virtual prototype as part of mechanical system of the coordinated simulation control system.The torque of the joints were dynamic controlled by adopting the method of system control law which were based on calculation method of moment,the simulation results showed that the robot arm had good dynamic response and accurate locus-tracking ability,to provide an effective reference for the design and development of the physical prototype.

Based on the building slabstone-installing robot with independent development,related research was carried out about the space linear trajectory planning. The kinematics analysis was carried on the robot,and simulated CP control method with five times polynomial curve interpolation was used for the trajectory planning in the joint space,which ensures the real-time synchronization and velocity continuity in the movement control of each joint. With the help of Matlab robot toolbox and Labview programming software,related simulation and experiments were done to complete the task of space linear trajectory planning on the end of the robot.

Stable enough wire driving force is the key to improve the forming quality.Not only to control the size of driving force,but also to ensure the stability of the extrusion filament process,the influencing factors of friction driving force analyzed.And the calculation formula of friction driving force can be derived by theoretical analysis.Wire feeder is the key to design the spray head system.According to the analyzed influence rule of the driving force,a kind of opening remote wire feeder is designed.It can provide large enough friction driving force to ensure wire feeding smooth,and has important practical reference value.

Through the simplified mechanical model of DF8B diesel locomotive radial bogie,the formula of coupling rod’s loads can be deduced.In the straight track condition with different train speed,the result of simulation and test can be got respectively by the simulator software SIMPACK and real vehicle test.Through contrasting the theoretical value,simulated value and test value of the loads of the coupling rod of the bogie,the accuracy of theoretical derivation has be verified.With the conclusion of the analysis,the factors affecting the coupling rod’s loads in the straight condition are founded and the result provides a theoretical basis to the radial bogie further improve.

According to the measured dynamic strain data,and calculated by the load spectrum,the damage of bogie frame is calculated based the S-N(stress-life) curve,providing a basis for determining the rationality of the relevant technical documents such as static strength test,fatigue test and finite element analysis.

Sometimes because of part structure or size in milling,when the workpiece need to inclined to clamp,the contour cannot parallel with the X axis and Y axis,which make the tool-setting difficult.The method to realize the semi-automatic tool-setting in milling this kind of parts by using photoelectric edge detector was introduced and combining with user macro program of CNC system,then using G68 to facilitate automatic processing.

Aiming at extraction of AutoCAD drawing schedule and interface problem of information management system,the structure characteristics of schedule were analyzed in detail,and the recognition and extraction method of schedule was put forward based on coordinate positioning.The steps of the method included:building selection set,structure identification of schedule,character recognition,the storage of virtual schedule,data output,etc.With the VB as the development platform,the recognition and extraction software of AutoCAD schedule was developed.The software didn't have any specific format limit of engineering drawing schedule,and it had strong flexibility and adaptability.Currently,the software runs well.

The rigidity and strength performance of the moving beam longmen processing center is determined by the design of the beam structure to a great extent.The static and dynamic characteristics of the beam are directly affected by the design and layout of the reinforcing bar in the beam structure.Based on the finite element method,the static and dynamic analysis of the beam for the moving beam longmen processing center were carried out,the deformation of the beam under extreme working conditions and the first six natural frequencies and modes of the beam structure were obtained.The results showed that the cross shaped reinforcing bar can not meet the requirements of the actual work.By changing the structure of the reinforcing bar into rice-shape,the deformation of the beam was reduced by 20.265% and the first mode frequency was increased by 4.405%,which shows that the method is reasonable and feasible,can provide a theoretical basis for the design of the structure for the beam component.

According to the physical model of Electrical Melting and Explosion (EME) single pulse arc,a two-dimensional mathematical model of EME arc plasma is established based on the magnetic fluid dynamics and Maxwell’s equations.By the numerical treatment of control equations and boundary conditions,the numerical simulation of the single pulse steady state arc is carried out based on secondary development of FLUENT software.Based on the simulation results,such as temperature field,velocity field,pressure field,and so on,compared with the related literatures,the correctness of the simulation is verified,which is helpful to the further research of EME technology.

The finite element simulation has been becoming one kind of common method used in the study of metal cutting.The ABAQUS was used to build the finite element model of milling for 7075-T7451 aerospace aluminum alloy.The geometry model,material law etc were built and the boundary conditions,separation criterion and friction conditions were determined.The whole process of milling was simulated and the prediction of chip shape,distribution of stress and strain,distribution of temperature and cutting force were achieved.The influences of mass scaling and mesh size on the prediction of cutting force were investigated quantitatively.These are the contribution for promoting the application of finite element simulation technology in metal cutting,and also is the foundation of milling parameters optimization.

Briefly introduces the automatic production equipment of rotary sound-absorbing board.In addition,a three-dimensional model of the rotating platform of Sound-absorbing board production line is established by the use of Solidworks.In order to predict the vibration of the rotating platform,a dynamics modal analysis using the software,ANSYS Workbench,is carried out for it,and we obtained its inherent frequency and its mode of vibration eventually.Consequently,it is good for us to have a knowledge of the vibration characteristic of the rotating platform,which provides an important reference for the production line of optimization design.

Assembling process of spacecraft plays a key role in its development cycle.To provide evidence for enterprise to choose the best process plan,method of evaluation of spacecraft’s assembling process plan based on fuzzy comprehensive evaluation and virtual assembly was proposed,in this method,target system of evaluating model was established;targets were evaluated by virtual assembly;then,a fuzzy comprehensive evaluation model was built.Finally,an assembly process of payload of spacecraft was development to illustrate the feasibility and validity of the proposed evaluation method.

Surface waviness is one of the important evaluation indicators for surface quality of micro abrasive air jet machining technology.Based on the experiment of micro abrasive air jet machining of silicon,the influences of process parameters and their interaction effects on surface waviness are studied.Surface waviness generalized regression neural network model is also developed.The results indicate that the nozzle traverse speed has the most significant effect on the surface waviness.The effects of standoff distance,working pressure of abrasive jet machine,the interaction of nozzle traverse speed and standoff distance,as well as the interaction of working pressure of abrasive jet machine and standoff distance are followed.While the interaction of working pressure of abrasive jet machine and nozzle traverse speed has insignificant effect on the surface waviness.The surface waviness increases with an increase in working pressure of abrasive jet machine,while it increases firstly and then decreases with an increase in standoff distance.It decreases with an increase in nozzle traverse speed.The combination of low working pressure of abrasive jet machine and large standoff distance,as well as the combination of high nozzle traverse speed either with medium-low or large standoff distance results in low surface waviness.The neural network model is developed according to the theory of generalized regression neural network.It is found that the model can give an adequate prediction of surface waviness after verification.

The current integration of standard aircraft parts management system and three-dimensional design software is not high,resulting in separation of application and management of standard parts,low design efficiency and adverse management of product life cycle.Basing on CATIA and ENOVIA VPM platform,develops a calling interface integrated into CATIA for standard parts with secondary development technology of CATIA.It realized real-time storage and call in the VPM for local standard parts,avoided data redundancy of standard parts and reduced the data size and operational burden of VPM system.Finally, describes documents management method of VPM system in accordance with its application.

Bulging and pressing is a new process for manufacture complex hollow parts,such as axle housing.For the forming of square straight arm filled in liquid and pressed of a 5t axle housing with flat die,the simulation is done by ABAQUS software,and the square arm area appears a significant concave.To eliminate this phenomenon,the pressing die is designed to concave curve on indent defect area of the straight arm.Using twelve groups of different concave curve mold,the simulation of pressing process is done,and the relationship between straight arm indent and mold curve chord length and concavity is given,and the structural parameters of the mold concave curve is given without indent on the square tube surface.Finally,the pressing forming test is done,and the test results agree with the simulation results.

Assembly line for scissors aerial vehicle of SM company cannot meet customer demands in quantity,the problem of production process chaos,low personnel utilization ration and low assembly line balancing ration need to be solved.Therefore,one improvement method based on the technique of value stream mapping analysis was proposed to work out the above problems.Firstly,according to the production status of the company,the current value stream map of GTJZ0608 scissors aerial vehicle was drawn up.Then,the main problems existing in the current production process were analyzed according to the current value stream map.Finally,through the application of lean production methods such as leveling production,pull production,changing the way of material delivery and production operation control,the production process was optimized,and the future value stream map was created.After above improvements,the production process of the product was optimized.As a result,the product assembly cycle can be shortened,and then the inventory and material handling distance can be reduced,at the same time,the personnel utilization ration and assembly line balancing ration can also be improved.

Measuring instrument for blind hole of inside surface of thin cylinder is mainly used to measure the position,dimension and form of the blind hole and at the same time to measure the machining and foundry quality by image for inner surface of cylinder.It adopts the CCD image acquisition and image processing technology,precision machinery technology,computer real-time control technology to finish the measurement.The measuring principle and method,the function and advantage,the overall structure of the instrument are described.The design of the optical imaging system,the design of the mechanical system,the image processing procedure has been introduced in detail.The experiment results indicates the measuring instrument has met the measuring function and accuracy demands of the compensated hole.

The material strength and fatigue performances of 18Cr2Ni4W and 34CrNiMo6 were measured for the problem of crankshaft material unification of a certain engine.The reliability of crankshaft with two different materials was calculated based on finite element simulation and stress-strength interference theory.The contrast analysis with traditional deterministic safety factor evaluation method was implemented.Reveals the disadvantage of traditional evaluation method,and provides theory support for material unification design of the engine crankshaft.

Thread joint is one of the most widely used joint in industry,agriculture and daily life.The quality of thread is an important element which determining its reliability.Some high demanding fasteners must be detected one by one.Detection process is a series of repeated actions.Specially designed automation equipment can greatly reduce the labor intensity,enhance the efficiency of detection.Therefore,the control system for automatic internal thread detection machine has been developed.This system aimed to realize the automatic detection of a certain size range of internal thread and digital detection results.PLC as the core control component,has realized the coordinated control of parts of the control system.Using the touch screen as human-computer interaction,can realize real-time display system status and test results.

The column is an important part of machine,that supporting the spindle box,ram,beams and other components,it has significant influence on machining accuracy of machine tool.Taking the stiffened plate structure,stiffened plate thickness as design variables,taking the quality of the column as the main evaluation index and the deformation,the first-order frequency as secondary evaluation index.Eight kinds of stiffened plate structure of the column were established and analyzed by 3D design software SolidWorks and finite element analysis software ANSYS,preliminary screening out the “O” type stiffened plate structure is the optimal solution,and then different thickness of rib plate of the “O” type column were designed and analyzed.The results show that “O” type rib stiffened plate with thickness of 14mm has the optimal comprehensive performance,the deformation is unchanged,but weight reduced 352kg and the first-order frequency is increased by 1.6%.

For the adaptive design of the large complex product,the ratio of the time required for new product design by adapting the existing design and the time required for redesign product can be used as evaluation index of design adaptability based on time costs.From the aspect of similarity,design reuse and customized flexibility,the adaptability was measured by retrieving the adaptive tasks of product design,and a new calculation method of design adaptability was proposed.Finally,an example of rail mounted gantry container crane was used to demonstrate the feasibility and practical value of the proposed method.