An polygonal tube electrode Electrical Discharge Machining (EDM) method is developed to improve the performance of conventional EDM process in machining particulate reinforced Metal Matrix Composites(MMCs) and the problem of hollow electrode chip during the EDM.Make a contrastive research on machining efficiency of particulate reinforced MMCs through two hollow electrodes with different cross sections,such as the round and the pentagon.In addition,orthogonal experiment is adapted to study particulate reinforced MMCs with different processing parameters on the efficiency to obtain optimal parameters for polygon electrode EDM.The experimental results show that the efficiency of machining such materials by the cross-section of pentagonal hollow electrode is higher than the circular hollow electrode,the maximum processing time is reduced by 51.8%;the optimum combination of orthogonal experiment is the pulse on time (32ms),the duty cycle(2 ∶3),and the peak current(7A).

In order to realize ductile-regime machining for tungsten carbide as optical die material,it was machined using Cubic Boron Nitride (CBN) tools under the assistance of laser heating and ultrasonic vibration.The cutting force variation characteristics in the three cutting modes,such as common cutting,ultrasonic elliptical vibration cutting,laser assisted and ultrasonic elliptical vibration composite cutting,are analyzed and the model of cutting force of tungsten carbide in laser assisted and ultrasonic elliptical vibration composite cutting is established.The experiments were carried out on an ultra-precision lathe assisted by YAG laser equipment and self-developed ultrasonic vibration device.The influences of cutting parameters,such as cutting speed and cutting depth,on cutting force were studied through a series of contrast experiments.The theoretical model and experimental results show that,because of the softening of the workpiece material and the interrupted cutting,the composite assistance of laser and ultrasonic vibration can largely reduce the cutting force while machinability of tungsten carbide can be remarkably improved.Furthermore,precision machining of tungsten carbide can be realized under certain optimized technological parameters.

The electromagnet of large gap magnetic drive system is the research object.The effect of electromagnet core material and structure parameters on the system driving capability was researched.The electromagnet core made by the Z10-T25 oriented silicon steel sheet was determined.So the system driving capability can be improved.According to the dynamic model of the system starting process,the acceleration control method of large gap magnetic drive system and starting the axial flow blood pump fast and smoothly was studied.The theoretical simulation and calculation results were compared with the experimental data.When the electromagnetic coil pulse frequency changed from 0Hz to 150Hz in the starting process,the blood pump accelerated from 0r/min to 9 000r/min.The experimental results of the outlet pressure p and flow rate Q of the blood pump are consistent with the theoretical simulation.The drive system can make the axial flow blood pump outlet pressure and flow rate achieve the control target value within 4s.

Based on the running status of gear box and the character of oil monitoring,the method was proposed which combine fuzzy comprehensive evaluation with Analytic Hierarchy Process(AHP).By extracting the indicators of the quantifier of wear particle and physical and chemical analysis, establish the comprehensive evaluation index system;using entropy weight method and AHP to determine the subjective and objective weight,then the combination weighting was obtained in multiplicative integration method.The membership function was established between aim level and the second level of evaluation,and use the membership of weighted to come ture comprehensive evaluation.Applying the distance analysis method to determine the overall conclusion,and then get the final evaluation result by relative degree.By means of the monitoring to experiment unit which was constructed by ourselves,the evaluation result consistent with the fact status,and then validating the comprehensiveness and rationality of this method.

The problem of package production line in Guilin JL corporation,such as irrational disposition of staffs and machines,cumbersome production cycle and unconformity of production design and actual requirements,were analyzed by using Value streaming technology.Value stream mapping was adopted to optimize package production line.At the same time,pull system was introduced to control production and manufacturing time was identified according to requirements collected from consumers.On this basis,adopting analyses of industrial engineering and following the principles of lean production,and implemented PDCA cycle,through the comparison of before and after improvement,the plan which enhances not only the efficiency of production lines,but also utilization rate of staffs and machines,the production waste was effectively refrained.

The rapid development in the international advanced manufacturing industry,to a certain extent,gave birth to the transformation of manufacturing industry as a traditional industry in our country.In order to follow the footsteps of European and American intelligent manufacturing,our country timely put forward the concept of 《Made in China 2025》,putting advanced manufacturing,combined with the Internet upgrade,to a new strategic height.Cloud manufacturing is an important product of the development of intelligent manufacturing;its unique advanced manufacturing mode and its enormous advantages of the parties to the industry has constantly getting more and more attention of the industry.Based on the introduction of cloud manufacturing concept,focus on the analysis of operation mode of cloud manufacturing from the macroscopic and microscopic perspectives,and the core of the development of cloud manufacturing——cloud manufacturing service platform architecture is described and analyzed.Finally,the development of distributed networked cloud manufacturing is prospected.

A novel 3-DOF hybrid manipulator was presented to pick and place the tubes on punch line.The workspace and optimization of the mechanism structure were carried out,several evaluation indexes of kinematics and dynamics performance are established for the object functions,workspace and static stiffness index for the constrains,parameters of level and tension spring for the design variables,and then a standard multi-objective optimization model can be built.The dimension synthesis is carried out by solving the multi-objective optimization with Non-dominated Sorting Genetic Algorithm-II(NSGA-II),the result of reducing driving torque of the motor 2 was selected in Pareto optimal solutions,meanwhile the selected solution can not significantly impaired other evaluation indexes.The selected solution was verified with kinematics,dynamics equation,the results show that optimized manipulator kinematics and dynamics performance has been greatly improved,and the theoretical foundation was brought forward to guide structural design and motion control.

During solving inverse kinematics problems of welding robot,there are often multiple solutions or even no solution.A trajectory planning method based on CAD/CAM technology was put forward to overcome the above disadvantages.Three dimensional modeling CAD technology and post-processing CAM technology were combined to realize the curve interpolation calculation of the welding trajectory and welding torch pose.Then the welding trajectory and welding torch pose were simulated,according to the accurate robot motion parameters of each joint gained by using MATLAB software.Through the simulation,analyse the changes of the welding robot kinematics parameters of each joint,and verify the accuracy and reliability of the data by compared with the theoretical mathematical model,provide theory basis for realizing the trajectory planning of different types of welding seams of intersection.

Engine block vibration velocity minimization is a key issue to improve noise and vibration characteristics of the structure itself and the connected component.Achieves the rate of change of vibration response with the block structural parameters through the virtual simulation analysis,and explore into the sensitivity problem for objective function and constraints influence on the design variables,in order to ensure the key design variables of vibration velocity and quality.Meanwhile,the weight relationships between structural quality and vibration velocity were coordinated effectively through the influence of block structure shape and size.The results showed that the vibration velocity was reduced by 23.87%,and the structural quality reduced 12kg in the improved process,and also verified the rationality and effective in the research of minimizing the vibration velocity of the block.

The method of reverse modeling plays a more and more important role in the innovative design of products.Combines the functional analysis with the morphological analysis,to acquire the knowledge of reverse modeling and obtain the new product model bases on function-form-parameter,and proposes a design method of product innovation based on design knowledge reuse.With the reverse modeling software Geomagic Studio and SolidWorks software as platform,innovation design of the splint is realized through knowledge reuse,which verifies the advantage of the design method,and provides a more effective solution for the innovative design of products in reverse engineering.

Laminated object manufacturing results in thermal residual stresses and deformation due to its high temperature techniques.Cooling gradients occurs due to the time differences in manufacturing processes.Considering the temperature gradients through thickness in manufacturing processes,the analytical solutions of thermal residual stresses and deformations are built.There are several cooling gradient models due to different manufacturing techniques.It is shown in numerical examples that cooling gradients result in thermal residual phenomenon through thickness.The effects of cooling gradient models on thermal residual stresses are discussed.The model can reasonably explain the bending deformation due to the cooling gradients in a workpieces.Bending deformation is actually a self-regulation mechanism to reduce residual stresses in the workpiece,which means that increasing the bending deformation can reduce the thermal residual stresses.This work provides a reliable theoretical basis for the optimization of laminated object manufacturing.

To realize the Anti-Slip Regulator(ASR)effect of the down-sized electric vehicles without hydraulic ABS with regulating the output torque of the motor,the integral separation PID control algorithm and the road automatic identification algorithm are employed.The control target value of wheelspin rate of driving wheels is determined by the automatic identification value or the empirical value according to the different working condition,and a pure-motor ASR is realized.A series of experimental simulations are carried out in different road conditions,including uniform pavement,bisectional road,transition coefficient road and chess road.The results show the proposed ASR can regulate the driving wheels wheelspin rates to the target value quickly and exactly,which means the control algorithms and strategies are effective.

According to the structure and principle of the extended-range electric vehicle,the parameters of the power system are matched to the target vehicle.The model is established by ADVISOR simulation software.And the dynamic performance,pure electric driving mileage and fuel economy performance of the vehicle are tested.The simulation results show that the parameters of the electric vehicle are reasonable and all the performance achieve the design objectives.

To improve NVH performance and to reduce noise of cars,plate thickness optimization of cars′ body structure should be taken.Developed a valid meta-model of the car,and chose thickness of head cover,floor,glass of rear door,glass of left back door and left rear door,which are with high body module contribution degree,as our optimization variable.Have designed and developed response model of target basing on optimal Latin experiment,and have verified the reliability.Have made optimized analysis on response model with MIGA.Inside noise is reduced after that,which proves that the method is with high veracity and validity.

The wheel fatigue life of truck is the main indicators to determine its performance.In order to better analysis and forecast the fatigue performance of wheel.Proposed a set of complete the finite element analysis method of the wheel’s fatigue durability based on the national standards of the dynamics bending and radial fatigue testing for vehicle wheel.Through established the finite element model of the wheel and the method used discrete curve as the cyclic loads in order to simulate the actual boundary condition of wheel structure more correctly.And then,the simulation result obtained its stress distribution and critical areas.By using software of fatigue analysis,the fatigue life of the wheel is calculated and analyzed.Afterwards,the dynamic bending and radial fatigue test are conducted and the test results are compared with the simulation results.Based on the contrast,the validity of the method is verified.This method can predict the critical areas and durability of the wheel structure under radian and bending loads accurately.Also it provide a guidance to evaluate its performance and lay a foundation for further design of wheel structure.

The joint surface of machine tools has an important influence on the dynamic and static characteristics of the whole machine.The identification of dynamic characteristic parameters of the joint surface is of great significance to improve the performance of the whole machine and shorten the development cycle.A method combining the LMS Test.Lab modal analysis and ANSYS response surface methodology was proposed to identify the dynamic characteristic parameters.The finite element model of linear motor feed system was established in ANSYS software based on the equivalent stiffness and damping value of joint surface,and the simulation modal analysis of the system was carried out.Modal experiment test was done by LMS Test.Lab.Comparison of simulated modal parameters and experimental modal parameters was done to modify the finite element model.In the end,the error of the experimental modal parameters and the simulated modal parameters is less than 8%,which verify the accuracy of the finite element model.

By taking a certain type of a large excavator as the research object,the chassis and track beams are fixed by multiple row of bolt groups in design.The three-dimensional model of all parts was set up based on the Pro/E.Then convert the format and put them into the ADAMS,adding a constraint condition to establish the virtual prototype system.Based on the ADAMS dynamic simulation analysis,the load condition of each articulated point could be imitated veritably.The simulation analysis is carried out on several typical working conditions.It is concluded that the position and the main force curve of the bolt group with the maximum load of the connecting bolt groups of walking frame in the work.The analysis results can provide data support for strength verification and fatigue calculation of connecting bolt groups of walking frame.The outcomes also provide reference for the optimization and reliability design of the connecting of walking frame.

The colony algorithm shop scheduling aspect of the application has been studied for its convergence rate in terms of solving the flexible job-shop scheduling problem is slow and easy to fall into local optimal solution,proposed a biological memory curve based on the principle of information pheromone update rules.The shortest processing time as the objective function objective function flexible job-shop scheduling,combined with practical examples using MATLAB to solve.By contrast with the basic ant colony algorithm and other intelligent algorithm analysis,based on the principles of biological memory curve pheromone update rule it proposed solving ability and has a good convergence capability.

By the titanium passivity,it is susceptible to generate passivation membrane,then prevent an electrochemical machining.Design to create a set of test device,adopts the model of DC,pulse to titanium alloy electrochemical machining for a large number of experiments.According to principle of current efficiency curve and through data processing and analysis,the electrolyte formula that is suitable for titanium alloy electrochemical machining electrolyte is optimizationed.

Automatic feeding machine for L-shaped nickel sheet is used in the production process of the battery protector,which can replace person to place L-shaped nickel sheet of right direction to the fixture.According to the particularity of the nickel plate structure,the whole structure of automatic feeding machine were designed,and the key components of the automatic feeding machine were designed and analyzed,including a feeding device,a straight-line feeding device,smart camera and four degree of freedom manipulator;the software and hardware of control system in automatic feeding machine was introduced,and design of the control system was completed.The prototype was debugged and tested,compared with the manual feeding method,the result shows that the overall performance of the automatic feeding machine designed is superior,the feeding rate is 90~100pcs/min,which is almost double the rate of artificial feeding;the qualified rate of the product can reach 99%,which is 8% higher than that of the artificial feeding.

Present researches on workshop layout optimization are mostly based on logistics cost minimization to build objective function. Builds objective function that considers operators’ labor intensity at the same time from the perspective of human factors engineering.Combines Systematic Layout Planning (SLP) with Genetic Algorithm (GA) for the study on workshop layout optimization,and use Matlab to solve the model,making up for the traditional SLP method of iteration time is long,the influence of subjective thought,and gets optimal solution quickly.Through the case of auto spare parts production enterprise,achieving the goal that logistics cost and labor intensity minimization,indicating this method can preferably get optimal workshop layout.

Briefly introduces current methods of gear finishing technologies and points out advantages and disadvantages of existing processes. A technology of gear barrel finishing has been proposed which elaborates processing mechanism of this technology and gives priority to complicated relative motion between the surface of the abrasive and the workpiece.A mathematical model has been established which derives formulation of calculating cutting speed and main factors that affect the processing effect are found theoretically.Analyzing the influence law of the factors by MATLAB.Using discrete element software EDEM,visually simulate abrasive particles in the system of the movement process and real-time observation of the movement of abrasive in the container.By comparing the abrasive particles on the tooth surface contact force under the different parameters,,laid the theoretical foundations for the experimental research and production application.

Pulse cold welding repair rate is a key factor in determining the quality of repair layer.In order to determine the effect of different repair rates on the temperature field of the pulse cold welding layer,a 45 steel specimen was machined to a rectangular parallelepiped with a size of 50mm×6mm×1mm.Firstly,a three-dimensional finite element analysis model was established,and the dynamic distribution of the temperature field at different repairing rates was simulated by the method of body generating load.The change of the temperature field feature of the repairing layer was discussed by the method of applying the heat generation rate to the unit which was constantly activated during the repair.And then through the DZMH-6 pulse cold welding equipment,the use of thermocouple and XSR30 paperless recorder to determine the real temperature field distribution.Research shows that:The temperature rise rate and the temperature peak of 2.3mm/s are larger than 2.5mm/s,and the temperature field results of numerical simulation are in good agreement with the actual measurement results.The use of life and death unit technology and body heat rate heat source can effectively predict the real pulse cold welding process temperature field.

In order to test the fatigue life of thin band and the maximum static friction force between thin band and the tension pulley with different tension,experiments were carried out in several groups by using self-developed band saw.The tension force effects the fatigue life and the resonance frequency,and the static friction force provides the cutting force for band saw.The above factors influence the cutting parameters.Experimental data,theoretical calculation and aided calculation based on Workbench are used.By force analysis and modal analysis,aimed to deduce the relationship between fatigue life and cutting parameters,provide an important theoretical basis for selecting the cutting parameters and tensile force of band saw.

A large number of bolt connections are used in the process of metro vehicle assembly,but there are lots of bolt failure phenomena.Selecting the M8×30 specification ordinary six angle stainless steel bolt as the research object,which is used in many bolt connects,the orthogonal failure experiment are made to ascertain the influence on bolt connection of the adjust gasket and the additives and their combination.The variance analysis and range analysis results show their influence degree.Moreover,the best and easiest to failure combination of various factors in bolt connection are received.

In view of the limitation of mass calculation,slow analysis velocity and complicated feature extraction of traditional time-frequency,the feature extraction method of diesel engine based on time-frequency distribution singular value spectrum was proposed.The discrete Dual-Tree Complex Wavelet Packet Transform (DT-CWPT) transform method and the discrete time-frequency distribution was studied,then the feature was extracted by singular value decomposition.The comparison of calculation efficiency and feature extraction effect was analyzed based on different working condition test of diesel engine.The results indicate that the method has high computation efficiency and good performance of accuracy.

For getting insight into the user demand,lots of researches about the user experience problems in product design were carried out based on the theory of “empathy”,in the aspects of systematic method and practical application.Firstly expounds the concept of product empathic design.Then,it is combed the research status of empathic design method from two aspects of macroscopic and microscopic.After that,the application research is subdivided into three layers,namely,the visual layer,the behavior interaction layer and the social reflection layer.By discussing the relationship between the three layers,the research trend of empathic design is prospected.

The prediction for equipment condition trend is not only one of the main tasks of fault diagnosis,but also an important research in this field.Especially,since the equipment maintenance mode changed from regular maintenance to predictive maintenance,in order to predict the trend of equipment condition accurately and formulate scientific and reasonable remedy,the prediction technology for equipment condition trend is particular significant.Therefore,the methods and research process for equipment condition trend prediction are introduced.Thus,combined with oil-monitoring technology,a new method of equipment trend prediction which is based on multi-source information fusion is proposed.