African blackwood is difficult-to-cut wood material.Milling cutters wear quickly in the wood cutting.Based on response surface method,the effect of process parameters on milling force in African black wood cutting was investigated and a second order nonlinear regression model was established to predict the milling force.Experiments show that the main shaft speed has the greatest influence on the cutting force and the regression model’s prediction is consistent with the practical value of the milling force.The model is helpful to optimize milling parameters.

The content introduces the principle of setting machines.For the problem of bad dynamic performance and weak ability of the dynamic performance of tenter tension,the digital filtering two degree of freedom PID control algorithm was designed,result the overshoot of the system reduced to 1.3%,the adjustment time shortened to 5s and the steady error was controlled in(80±1.1)kN.In the light of the large initial error of stretching tension leads to integral accumulation and eventually cause the system oscillatory or divergent,the integral separation PID control algorithm was designed and result was controlled within the process requirements of the 20N and effectively reduced the stretching tension overshoot.The rear spindle position was controlled within 20mm and stretching tension and synchronous coupling control were realized.

To solve mixed-model two-sided assembly line balancing problems type Ι effectively,an Improved Teaching-Learning-Based Optimization(ITLBO) algorithm is proposed.In this algorithm,the random key method is used to generate initial solutions,and then a new self-learning phase is introduced to strengthen the local search ability of the proposed algorithm.In addition,according to the characteristics of the mixed-model two-sided assembly line,a novel heuristic decoding method is put forward.The decoding method tires to reduce the sequence-dependent idle times in the decoding process,balances the workloads on two stations within a same mated-station to ensure the workload balance,and also puts forward a new strategy to deal with the last mated-station for the purpose of further reducing the number of stations.The proposed algorithm solves all the benchmark problems of the mixed-model two-sided assembly line,and it is compared with six different algorithms.Computational results show that the proposed decoding reduces idle times effectively,and the proposed algorithm is superior to other algorithms.

In order to satisfy the high demand for data acquisition and information interaction in the wisdom workshop management system,take the LabVIEW software as development platform.Through the combination of the Wireless Sensor Networks(WSNs) and serial communication,using technology of calling dynamic library to implement parallel multichannel data acquisition.The feasibility of the data collection method is verified by the experiments.The results showed that the workshop information perception and analysis system,based on LabVIEW,about workshop environment monitoring,production condition monitoring and fault diagnosis of equipment is effective to deal with various data,analysis,real-time display and storage.The experiment has a certain reference value to optimization of furture wisdom workshop management system.

Under the network environment,in order to achieve the integration management of the distributed parts resource and,an ontology-based integration architecture for parts resource library is proposed to satisfy enterprises' requirements for parts information sharing and reuse in the knowledge level.Based on this,an ontology-driven method for distributed parts resource library construction is studied,and the automatic integration algorithm and its example of parts resource library are also presented,based on the shared ontology.In addition to discover parts resource as much as possible,ontology-based parts resource semantic retrieval method is adopted.At last,a prototype system is developed to verify the feasibility of the methods discussed above,and indicate that it is good way to provide a semantic-based and integrated parts resource retrieval and application entrance for designer to further improve the utilization and reuse degree of the existing parts resource.

A wheel type robot joint torque sensor is designed and it is mainly used for real-time detection of robot joint torque,robot flexible control and human-computer collaboration.In order to study the torque sensor of robot,the mechanical analysis of the robot is carried out firstly,and the position of the strain is determined.Then the deformation of the strain is analyzed,and the choice of the material and the optimization of the material are analyzed by using the finite element analysis software.At the same time,the sensor signal processing circuit was designed.Finally,through the calibration of sensor static calibration device,got the sensitivity,linearity,hysteresis error and other performance indicators.

Smooth path generation for Automated Guided Vehicle (AGV),which provides a smooth path for AGV moving,is the basic process of AGVs.Based on the concept of easement curve,use symmetrical fourth-order curve to solve the problem of smooth path generation.Taking differential AGV for example,we also analyze the maximum speed and the mechanical properties of AGV on the curve.The results show this algorithm helps to improve the AGV’s flexibility.

Aiming at solving defects such as slow convergence speed,low efficiency,frequent local optimum,and even the emergence of deadlock in the path planning of introducing the traditional ant colony algorithm into mobile robots,an advanced ant colony algorithm is proposed,which establishes the working environment of the robot by grid method,improves updating mode of information pheromone,sets the pheromone concentration threshold,introduces treatment strategy of deadlock,and thus improves the state transition probability and increases the diversity of solutions.Simulation tests for mobile robot path planning are carried out in the grid environment.The results of simulation tests show that the improved ant colony algorithm can narrow the search scope of the optimal path and reduce the number of iterations,improve the search efficiency of the optimal solution,and can obtain the global optimum collision-free path.

Work-study is an effective way to improve the competitiveness of manufacturing industry in low investment situation.Based on 5W1H method and ECRS principle,the IE methods were used to optimize air conditioner stop valve assembly line process in DAHT company.Through the job decomposition and composition within working procedure,bottleneck procedure improvement and time measurement,production line balancing rate increased from original 68.58% to 92.35%,WIP(work in process) from 40~60 reduce to 16,and number of workers was reduced by 8~10,so that workshop and logistics was uniform and reasonable.

For the problem of batch planning of 3D printing,a method based on work-piece layout was proposed.According to the features of 3D printing process,the objective of batch planning was set to minimize the total printing batches and the height difference of the printing parts in each batch.The printed parts were coded with integer numbers in sequence and the permutations of the sequence number formed the feasible solution set of the problem.In decoding stage,the printed parts were laid into the machine’s printing table orderly according to the sequence of solution.If the machine’s printing table was not with enough space to accommodate the printed parts further more,the next printing batch was arranged.This finally reached the printing batch scheme as well as the value of optimization objective function.For simplification,the minimum bounding rectangle of the horizontal projection shape of the printed part was adopted in part laying.Thus the problem of two-dimensional shape layout was simplified as the problem of rectangular packing.The lowest horizontal line algorithm and the Bottom-Left rule were applied in the rectangular packing.The lowest horizontal line segment of packed area contour was searched and updated repeatedly during part laying until the part could not be accommodated any more.The genetic algorithm was applied in searching the optimum solution.The proposed method of this paper was verified by example.

Aiming at the deficiency of the bus frame design optimization based on the static fore,the design optimization of the bus frame based on dynamic peak force is proposed.The dynamic model of the vehicle and the road model were established in this method,and the dynamic peak force of the frame was calculated.The finite element analysis and design optimization model of the frame were established based on dynamic peak force.One bus was taken as an example,the quality of the frame is reduced by 8.84% percentage through the method of the bus frame design optimization based on dynamic peak force.The strength and stiffness of the frame after optimization meet the requirements.The results show that the method of the bus frame design optimization based on dynamic peak force is reliable.It can be directly applied to any vehicle and structure design optimization under any condition without specific consideration dynamic load coefficient of the experimental research under different working conditions.It also shorten the design time and save the development costs.

In view of how to relief driving fatigue to the drivers effectively,designing a manual-intelligent dual-mode clutch control system which has simple and novel structure.The system includes four parts,which are clutch mechanical assembly,manual controlled clutch equipment,intelligent clutch controlled equipment and controlled system.According to the character of the system,mathematic model of the intelligent controlled mode is built.Applied the simulation software Matlab/Simlink,combined with the system controlled mode and Mamdani method fuzzy controlled strategy,the simulation to the dual-mode clutch control system is carried out.According to the loading test in car,the result shows that under the intelligent controlled mode,it takes 2.7s from pushing down the clutch pedal to clutch engagement,compared with the simulation time less than 0.4s,test result is similar to the simulation result.Moreover,the dual-mode clutch control system can decrease the shifting impact during the clutch engagement process,which improve the vehicle ride performance.

Presented an approach to design H_∞robust control of active suspension of train,it reduced the vibration of vehicle effectively.It established the dynamic model of vehicle vertical vibration based on a reasonable simplification.Taking the uncertainty in the name object and the performance requirements into account,it selected appropriate weighting functions to design the H_∞output feedback robust controller based on the mixed-sensitivity PS/T generalized model,and used DGKF law to develop the sufficient conditions for the existence of controller.The results show that the mixed-sensitivity H_∞robust controller can suppress the vertical vibration of car body effectively and ensure the riding comfortability and the running stability of train.

Considering electric power steering system with 2 DOFs model of vehicle.Established the model of electric power steering system take into account system of friction,bumpy roads and unmolded part of system.Then putting forward a kind of electric power steering dynamic sliding mode control system with disturbance observer.Then willing the system of interference,unmolded part of system as a general system of outside interference.Observable the interference of the system,selected the appropriate parameters of system,then making the observation error index convergence.With the system with disturbance observer.The dynamic surface sliding mode variable structure controller inversion is designed step by step by using Lyapunov stability theory.Avoided the problem of integral expansion compared with the traditional inversion controller,simulating the electric power steering system with 2 DOFs model for vehicle simulation with Matlab /Simulink with the influence of random disturbance of road bumps etc.The simulation results show that the controller under the action of the steering wheel torque in the interference of output is steady,strong robustness.Also it improves the portability of the system.

Mainly discusses the suitable design for primary reinforcement server’s comprehensive protection which can be used in vehicular environment.Introduces the design scheme,mainly introduced the vibration design,thermal design,electromagnetic compatibility design,noise reduction design.In every detailed design a sketch of the detailed implementation method and main structure sketch map were given.The primary reinforcement server has been used in the engineering successfully,it has good performance in test;the results indicate that its performance index achieves the requirements of vehicular environment,which can be used as a reference for similar engineering design.

Aims to achieve high efficiency and high precision arc machining by using the intelligent control,the ultrasonic vibration,electromagnetic excitation and rotating electrode combined with other factors,and the arc machining CNC system is worked as research subject.To coordinate the modules to be operated efficiently,designs arc machining platform and the CNC system of this platform.The processing platform adopts X、Y、Z three axis and rotation axis linkage machine tool,the CNC system employs open master-slave control system based on industrial PC.The design of the main control interface is projected by LabVIEW software.Finally,with the establishment of the processing platform and the design of CNC system,the research achieves arc machining with the rotated ultrasonic auxiliary electromagnetic excitation modulation.The research provides a economical and high precision processing equipment to non-traditional machining.

The limitations of 1D tolerance analysis by dimensional chain and the advantages of 3D tolerance analysis were analyzed.3D dimension and tolerance analysis of the gap between air conditioning pipe of chassis and front sub-frame unit was carried out using 3DCS software.The unreasonable components that cause assembly interference were found out by comparative analysis of the main contribution factor.And then,the product structure and tolerance can be optimized,assembly process can be improved.It shows that the method can effectively carry out assembling tolerance stack-up analysis and evaluate the assemblability of product.

In the information transfer pattern based on design model,according to the requirements of information defining,transferring,and management in process design,the basic attributes of the process model which include definition of process information,expression of process design intent and the data carrier of process information are summarized.The related data of process design basis,process planning,detailed process designing,process file exporting,process approving and management in whole process design is formally defined by using the parameterization as the main way.Points out the five correlation mechanism of the process modeling in CAD system,and according to the integrated feature of the process model,designs two new correlation mechanisms which include the File Link and Capture/Resource Link.On the basis of parameterization and 3D annotation expression way in MBD technology,the way of geometric element references,capture link and file link is designed to enrich expression way in MBD technology.Finally,the design flow and instance of process model in integration environment of 3D CAPP are given.

With the mechanism of plane cam as the main subject,chooses SolidWorks as the development platform for cam profile parametric CAD system and makes use of the programming environment for the combination of the SolidWorks API library with Visual Basic 6.0.By the check analysis of the cam profile,generates accurate cam profile in SolidWorks and outcomes its movement chart in VB as well as its automatically corrected cam circle radius,successfully establishing the parametric modeling of disc cam.Also makes motion simulation of the established cam assemblies by the use software Motion in SolidWorks.As a result,it verifies the reliability of the system.

Theoretical research is conducted on dynamic analysis of vibration suppression of the blade with viscoelastic damping block.Using complex modulus model to represent the constitutive law of viscoelastic material,the blade is simplified to single degree of freedom model,to achieve natural frequencies and harmonic response in the frequency domain.The analytical dynamic model of the blade with a viscoelastic damping block at the root of the blade is established.Viscoelastic damping block in the form of the massless complex stiffness spring is introduced into the system.Subsequently,based on the single degree of freedom model,complex eigenvalue method is adopted to analyze the contributions of natural frequency,loss factor and response on the resonant frequencies and response level.Finally,analytical and test results are compared and mutually confirmed,showing that all the viscoelastic damping served an good role in vibration suppression.

There are many actions contained in automobile assembly,using wire installation position of automobile left tail gate as examples to put forward a new kind of design method of standard time that is modular design method in order to improve the efficiency of formulating standard time.Based on Methods-Time Measurement-Universal Analyzing System (MTM-UAS),the assembly action can be divided into constant action elements and variable action,and the process contained repetitive process is as a module which formats standard time formula.The five processes that exist in “laying wiring harness” assembly work are applied by this method,concluded standard time formulation of five module by a module as a process to design.The standard time of process analyzed by new method and MTM-UAS is identical by comparing,but analysis speed is improved.It can be seen that the modular design method of standard time can improve the efficiency of the time analysis,and it can be extended to all process contained repetitive action.

In the full 3D (three dimensions) manufacturing process,the 3D design model is the main carrier of product data to transmit the manufacturing information.Through a lot of survey and test,it is found that the 3D model should possess 4 attributes to satisfy the integrity of manufacturing information and be able to avoid the obstacles in different CAD/CAM platforms.The parallel transmission mode,using the main model (the design model),is proposed to solve the complete expression of four elements of the design model in the manufacturing stage;then,the main model derives lightweight model and the process planning conversion method,which realizes the production of some products and lays a solid foundation for digital design and manufacturing.

The number of cells is a key factor of Cell Formation(CF) problem.After analysis the defects of currently validity function,a new validity measure and a algorithm which can obtain the optimum number of groups are both proposed,these are based on the Fuzzy C-Means (FCM) algorithm and the feature of CF problem.The new validity measure take into account the number of machines and parts in the cells,the essence of CF is measured by group efficiency.It can eliminate infeasible solution which there is no machine in the cells.The new algorithm is experimentally demonstrated using several well known CF examples from the published literature.

Thin-walled tubes are widely used in vehicle bodies because of their low costs and high energy absorption capacities.Under impact loading,tubular structures may deform in three modes:progressive buckling,euler-type buckling or dynamic plastic buckling,among which the progressive deformation usually occurs in pure axial loading is the best for energy absorption.In an actual accident,oblique impact is more common and euler-type buckling happens frequently.Aims to enhance the crashworthiness of thin-walled tubes in both axial and oblique impacts.Firstly,7 kinds of tubes with different cross-sections were investigated under different impact angles,and the Specific Energy Absorption(SEA) was evaluated.By simulating the 0,15 and 30 degrees impact,the best tube with regard to crashworthiness was chosen for further optimization.Then,taking the SEA as the objective function and the maximum impact force F_max as constraint,the tube’s parameters were optimized by using metamodel method.Finally,the optimization result is achieved and the tube’s crashworthiness in oblique impact is greatly improved.

Using ANSYS Workbench to build finite element model of the roll for the rolling device that transmission device was improved.Consider different bearing stiffness,analysis the change law of the natural frequency of the roller under different bearing stiffness,and obtain range of the first、second、third natural frequency of the roll.On that basis,using RecurDyn to build the multibody dynamic model of the rolling device system,obtain the time domain waveform and frequency domain waveform of the roll torque;compare the frequency component with the natural frequency of the roll to ensure the smoothing run of the rolling device.At last,the smooth operation of the device is verified by measured date.

Product quality is the source of enterprise benefits,for the spiral bevel gear,firstly,the production process of the spiral bevel gear was analyzed;Then,by applying Statistical Process Control (SPC) theory and method,the key points of quality improvement was determined and the process capability of the control points were analyzed and the quality improvement measures and plan were formulated.Finally,the regression analysis and the full factorial experimental design are conducted to find the optimal combination of the key factors and the influence of various factors,such as carburizing temperature,carburizing holding time,quenching temperature,tempering temperature and carburizing holding time.Through the implementation of the success of this project,the failure rate of the spiral bevel gears was reduced,and customer satisfaction was improved,the significant is effect.

Warp knitting machine take-up mechanism was composed of worm-gear retarder and chain transmission.In service life of the knitting process,the worm wear phenomenon appeared.The coiling force cannot be precisely calculated.For obtain the reason of worm wear,using wireless torque measurement system.Torque of the worm output shaft was measured.The worm torsion load signal mapping was obtained.The reason of impact load showned in the mapping and worm wear failure were analysed.The design method and the structure were improved.

The BP neural network,used in the study of fault diagnosis for rotating machinery,is easy to fall into local minima,and then the global optimal solution could not be obtained,that results in a poor classification and recognition rate of couple rub impact fault.Based on the analysis of an Empirical Mode Decomposition (EMD) method and a BP-AdaBoost method, puts forward a new algorithm of fault identification combined with the advantages of them above.First of all,an Empirical Mode Decomposition(EMD) method is used to decompose vibration signal from the rotor,for the aim of removing background noise signal,so the fault feature of rub impact signal of rotor system is obtained.Then a BP-AdaBoost model is used for the recognition of three kinds of different conditions.The analysis results on the experiments data show that the recognition rate of this new method is better than that of a single BP neural network.