Abstract:The test method of vehicle stability under extreme adhesion conditions based on the unsteady constraint test system was proposed. The unsteady constraint test system model was set up. Based on the Matlab/Simulink, the dynamic simulation system of unsteady constraint dynamics test system for the Chery A3 car was established. Using the simulation model, the stability control performances of the independent vehicle with or without ESP and test system under extreme adhesion conditions was simulated and analyzed. The study results indicate that the test method of vehicle stability under extreme adhesion conditions based on the unsteady constraint test system is feasible, safe and reliable, which could provide a reliable test platform and effective test verification method for researching and designing ESP control system.

Abstract:In order to measure and debug control strategy for vehicle stability on the low friction road, the vehicle stability control test system was developed, which were composed of the vehicle body path and attitude model, the vehicle stability controller model and the double CAN nodes data acquisition model. The data synchronism among each model was resorted to the signal of pulse per second, which was output by the GPS receiver. The CAN bus was employed to transfer data between models. More than four technology methods were introduced in details. They were the test method of vehicle side slipangle, the installing and initial alignment of inertial measurement unit (IMU), the time delay compensation of signal transforming and data transmission for GPS receiver and IMU, and the quickly transmission realization from serial input to CAN output. The systematic road way tests verified the functional reliability of the proposed system. The test system developed CAN nodes or employed the vehicle CAN bus to achieved the information of standard sensors included in ESC and engine management system. The real data was provided for understanding the vehicle’s state on the extreme operation conditions. So the developed test system provides an effective means to analyze vehicle stability control strategy. 

Abstract:A heavy-duty truck cab was analyzed and lightweight designed by using topological optimization method. Performance of the initial cab and lightweight structure was compared. It indicated that the front pendulum impact property of the cab and roof static pressure performances of the high-roof cab were improved when structural strength, rigidity and low-frequency natural vibration characteristics of the cab were not lower than the initial cab. Meanwhile, structural mass of the cab was reduced by 46 kg without changing of cab materials. A good lightweight design effect is acquired.

Abstract:Aiming at the lack of specific energy absorption area and components for flat truck cab, a method for improving the cab’s crashworthiness was proposed, which was realized by reallocating the power dissipation of each component. Referring to rule ECE R29, finite element method was used to simulate the pendulum collision process of some real vehicle to distribute the power dissipation by changing the thickness of components of cab. Living space of the cab after collision was evaluated to analyze the relationship between it and power dissipation, and experiment was carried out based on the analysis result to give some reasonable instruction. The analysis result showed that an appropriate increasing or decreasing of power dissipation of each component could optimize the crashworthiness of cab effectively. 

Abstract:According to the theory of hybrid electric drive train and requirements of working properties and transmission characteristics of tractors, a drive train for parallel hybrid electric tractor (PHET) was designed. Evaluation indicator and calculation model for dynamic and economic performance of hybrid electric tractor (HET) were suggested based on the theory analysis of traction characteristics of HET. The parameter design methods of each component of drive train were discussed. The theory of design and calculation method for drive train of HET was proposed. Taking a designed HET as study object, the changing relationship of driving force and climbing property with the speed changing of engine and motor under different gearshift when engine was working on 60% and 40% of load, and the changing relationship of equivalent energy consumption for 1h steady operation on plowing with the speed changing of engine and motor under different gearshift were analyzed by calculating. The calculation result of plowing status was checked by simulation model. Results showed that driving force and climbing property were directly proportional with the load of engine, but speed matching range of engine and motor decreased with the increasing of working load of engine. Moreover, when plowing, the error rate was not over 4% in maximum between calculation result and simulation result, and when increasing the speed of engine and motor, equivalent energy consumption increased under a certain gearshift. Furthermore, the energy conservation of HET was higher by 24% in maximum compared to traditional tractor with the same power. 

Abstract:An adaptive fuzzy neural network was built based on Takagi-Sugeno model. The inference rules were obtained by training the fuzzy neural network. The simulation result proved that the fuzzy inference rules based on Takagi-Sugeno model could infer driver intention excellently and hybrid vehicles’ control strategy could be optimized based on driver intention inference, thus more hybrid vehicles’ fuel consumption could be reduced.

Abstract:The transient unsteady two phase flow of high-power variable speed hydrodynamic coupling was numerical simulated based on the 3-D multi-phase flow theory and computational fluid dynamics (CFD) by using the sliding mesh method and the characteristics was predicted. The pressure and velocity distribution were analyzed to reveal the flow rule and characteristics of flow field. The reduced efficiency reasons were revealed. The theoretical calculation was compared with the external characteristic experiment under different filling rates. The maximum error was less than 15% between computational result of original characteristics and experiment results, and the correctness of theory method was verified.

Abstract:Mechanized planting mode and sowing rate was conducted in Qingdao from 2009 to 2011. The result showed that both of the two factors had significant influence on wheat yields. The wheat yields in small-wide-narrow mode (28cm+12cm) was the highest, which is 15%～30% higher than the large-wide-narrow mode and large-equal-row mode. When the sowing rate increased by 10%～20%, the yield increased by 2.2%～15%. The reason of yield increasing in small-wide-narrow mode and yield decreasing in large-wide-narrow mode was analyzed. 

Abstract:A cultivator which can achieve the purpose of high straw returning by rotary tillage with double roller was designed. The overall structural design and working principle of the cultivator were introduced. The field tests were conducted in order to examine its operating performance. The results of field tests indicated that the cultivator could realize multiple functions at the same time, such as the high straw mulching and returning, soil crashing, and surface leveling. The working qualities of cultivator which met the agrotechnical requirement of rice sowing and transplanting were as follows: the tillage depth of 158.7 mm,the stability of tillage depth of 84.86%, the straw coverage rate of 94.19%, the surface roughness after rotary tillage of 25 mm, and the productivity of 0.87 hm2/h.

Abstract:The working characteristics of walking type transplanting mechanism used in wide-narrow row planting was described. According to its characteristics, the planetary gear train with two levels of crisscross shaft was used in walking type transplanting mechanism and a transplanting mechanism used in walking type transplanter was proposed. The structure features and working principle of the wide-narrow row transplanting mechanism was analyzed. The angular displacement and the influence of the gear spiral angle. The kinematic model of the transplanting mechanism was built in the space coordinates system, and the displacement equation of the seedlings tip point was got. The parameters were analyzed and optimized by programming. The virtual model of the proposed transplanting mechanism was built with the optimization parameters. The theory model was verified by simulation and experiment. This transplanting mechanism could realize wide-narrow row rice. 

Abstract:Sliding of ground wheel will cause seed missing and quality decreasing. In order to solve the problem, a planetary geared ground wheel for no-tillage planter was developed. On the basis of analysis of structure and force of the wheel, the factors affecting performance of ground wheel were found. The experiments were conducted with different kinds of ground wheels in tillage and no-tillage soil. It was found from the comparative experiments that the anti-sliding ground wheel had minor sliding rate and steady performance. 

Abstract:The general explicit nonlinear finite element program ANSYS/LS-DYNA was used as a tool to research the influence of tillage depth and operating speed on operating resistance of the multiplex-modality subsoiler, as well as to study the significance of operating resistance reduction of the multiplex-modality subsoiler compared with the standard arc-shape subsoiler. In order to prove the reliability of the finite element analysis method, the operating resistance of the multiplex-modality subsoiler and the standard arc-shape subsoiler was tested in a soil bin. The result showed that there was a same varying trend between the operating resistance data obtained by the finite element method and soil bin test, and the finite element method was suitable to the research of the performance of subsoiling. With the fixing operating speed of 4~5km/h, average operating resistance of the multiplex-modality subsoiler reduced by 44.07%, 43.71% and 33.83% than of the standard arc-shape subsoiler, based on tillage depth of 300mm, 350mm and 400mm, respectively. All these data proved that the multiplex-modality subsoiler had a significant effect on operating resistance reduction.

Abstract:A piezoelectricity vibration table was designed for seeding precisely the small size of seeds of some vegetables, trees, flowers, etc. The piezoelectric vibration driving system produced the mechanical micro displacements with the applied electric field. The micro-displacements amplified by the amplification mechanism drove the seed dish vibrating and produced the boiling movement beneficial to suck seeds. The mathematical model of piezoelectric vibration was established. The static and dynamic state properties of the variation table were analyzed and experienced. The experimental results showed that the piezoelectric vibration system had a higher drive capacity with 90～110V electric voltage. Vibration amplitude achieved 131mm, vibration frequency was at 13～55Hz and adjustable (resonant frequency of 25Hz). The piezoelectric vibration table has better characteristics and higher seeding performances. It runs smoothly and meets the agronomic demands for precise tray seeding. 

Abstract:Simulating models of air-velocity distribution and droplets deposition were developed based on CFD technology. The simulation boundary conditions and model variables were defined according to the working parameters measured from the mist-sprayer. Based on these models, air-velocity distribution characteristic and droplets deposition pattern were obtained on various simulation condition such as different air-assisted velocities and nozzle installation angles. The relative errors of simulated results were confirmed through corresponding experiments on the same condition. The result showed that air-velocity distribution of the mist-sprayer was more advantageous to obtain better effect of droplet deposition when the nozzle installation angle was in the range of 5° to 10°.

Abstract:In order to study the process of charged droplets impacting the plant target interface，a test method by using PDPA was given. Both the morphological characteristics of charged droplets after impact and its causes were analyzed. The measurement results indicated that the special space movement form of charged droplets determined their unique morphological characteristics after impact. Charged droplets after impact would adhere to the interface or rebound but never splash. The existence of more fine droplets made coalescence phenomenon remarkable so as to increase the charged droplet size but decrease their number. The critical value of K for determing a single droplet’s adhesion or rebound after impact was not suitable for the process of charged droplets impacting the plant target interface. However, 30，the critical value of normal Weber number，could be a reference for determing charged droplets’ adhesion or rebound after impact. Larger tangential velocity may encourage charged droplets to rebound from the interface after impact. A part of normal kinetic energy of charged droplets would translate into tangential kinetic energy after impact. 

Abstract:From a perspective of agricultural machinery and agronomy combination, a method was proposed to analyze corn production mechanization system. Based on the analysis of background and conditions, an analysis framework of corn production mechanization system was put forward, which was focusing on technology integration, organizational integration and management integration. For technology integration, the available agricultural and agronomic technologies those can be combined in the process of production mechanization were analyzed. For organizational integration, the existing categories of service organizations of corn planting and agricultural machinery were summarized to analyze the integration idea and method of the combination of agricultural and agronomic technologies. For management integration, suggestions on resource management, task adjustment and process management were proposed to promote the corn production mechanization. 

Abstract:Based on dynamic simulation, two sections spiral sugarcanes lifter was designed and a sample machine was made. The effect rules of the two sections spiral sugarcane lifter were got through experimental test associated with the application of high-frequency photograph technology. The experiment results showed that, the two sections spiral sugarcane lifter worked well with lodge-angle of 45°~165°. Furthermore, the lifter worked best when the parameter of movement was 0.59, and the picking angle of setting was 5°, and the transportation angle of setting was 60°.

Abstract:In order to optimize the operation parameters of the processing tomato fruit-vine separation mechanism, a rotary roller-type separation bedstand was designed. Mathematical models that described relationship between the performance indexes and influence factors of the separation mechanism were established by applying quadrate regression experiment with general rotary design method. The tendency and regularity of the separation performance influenced by the factors were analyzed. For the Ligeer 87-5 processing tomato, with a certain tomato separation rate, tomato damage rate and tomato impurity rate, the roller rotation speed was 21r/min, cam plate rotation speed was 42r/min, deflector rod oscillation amplitude was 110mm by parameter optimization.

Abstract:A net self-wrapping mechanism for round baler was designed. The cam was used as transmission and control mechanism. The oscillating linkage was used as cam follower. The traction unit, wrapping unit and cutting unit were controlled for wrapping, recording and cutting. The wrapping performance experiment showed that this device could wrap dry bales of 80～120 cm width and silage round bales of 80～100 cm width. The most cost-effective operation was wrapping dry bale of 1.2 m width in three laps or wrapping silage round bale of 1.0 m width in four laps. 

Abstract:An optimization design method based on 3-D inverse design method and CFD was developed by combining design of experiment method, response surface method and simulated annealing optimization calculation. The method was applied to a centrifugal fan blade design by setting the impeller efficiency and the circulation distribution parameters as the optimization object and the optimization design variables respectively. The efficiency was improved by 2.2% with the optimization method. The effects of the circulation parameters and their interaction effects on the impeller efficiency were analyzed according to the constructed response surface between the design parameters and the impeller efficiency. It is shown that the inlet circulation distribution on the hub plays an important role on the efficiency. Comparing with the hub, the circulation distribution shape on the shroud has more influences on the efficiency.

Abstract:The four key parameters, including reaction time, reaction temperature, the amount of corn stover charged to definite liquefying reagent, and the dosage of catalyst affect the efficiency of corn stover liquefaction were investigated. With the help of SAS software, rotational quadratic regression design and response surface analysis, the relationships among unliquefied corn stover residue and reaction time, reaction temperature, the amount of corn stover charged to definite liquefying reagent, and the dosage of catalyst were studied. The mutual interaction of the four parameters was quantificationally described. The experimental results showed that with liquefying reagent of 100g, the reaction temperature of 158℃, the reaction time of 63 min,the amount of corn stover meal charged of 17 g and the catalyst dosage of 2.7g,the liquefied products could be optimized with only 0.2% unliquefied. 

Abstract:To investigate biomass devolatilization characteristics heated by solid heat carriers at high heating rate， experiments on the velocity field of biomass particles were conducted with particle image velocimetry (PIV) during the flowing of ceramic balls and pulverized biomass powder in a vertical pipe. Based on the PIV experimental results, the calculation method of residence time of biomass particles was determined. Flash devolatilization experiments of corn stalk were performed with a down flow tube reactor heated by ceramic ball heat carriers at 400℃, 450℃, 500℃ and the char was collected at the drop distance of 100 mm,400 mm, 700 mm, 1200 mm of the tube, respectively. The devolatilization percentages of the char were analyzed with ash tracer method. Results indicate that the experimental data have excellent repeatability, but the data are not agreement with the model well. The experimental data coincide with the model to great extent when the movement function of the biomass particles is involved in computation of the models. 

Abstract:Choosing lignite mixing with sawdust as object, the effect of calcium salt catalysis on SO2 and NOx emission was analyzed by using circulating fluidized bed reactor. The ash elements groups and mineral composition of ash samples were measured through X-ray fluorescence spectrometer(XRF), X-ray diffraction(XRD) and inductively coupled plasma atomic emission spectrometer(ICP). The result showed CaCO3 had a certain effect on SO2 and NOx emission reduction. The addition of limestone had obvious effect on NOx emission reduction with α=1.0. NOx production reduced with the decreasing of sawdust content. The removal of SO2was controlled by reaction temperature. Under the condition of temperature of 700~900℃ and Ca/S of 2.0, desulfurization was the best. The ash melting phenomenon disappeared with the effect of CaCO3. 

Abstract:According to the aquatic trace identity in the existing regulatory system, a certification and traceability regulatory system based on USB Key was designed. Firstly, several authentication technologies were analyzed focusing on the advantages and disadvantages. Secondly, the key part of USB Key hardware circuit, software system and the certification process of USB Key aquatic products enterprises were designed to solve the security issues of aquatic information transmission. Finally, the aquatic product enterprise certification and traceability monitoring platform was applied in Jiangsu province. The results showed that the regulatory system was convenient, safety, stable and reliable. It can realize the origin of quasi-out, market access, business certification and real-time monitoring of aquatic enterprise governance traceability system.

Abstract:In order to reduce the losses during logistics of aquatic products and improve the informationization level in aquatic products cold-chain logistics, a wireless sensor network (WSN) based on real time monitor system was proposed for aquatic products cold-chain logistics with ZigBee protocol and CC2530 wireless sensor SoC. The system included a sensor node designed for temperature data collection, a coordinator used for data upload and ZigBee network organization, a remote management system developed for cold-chain real time monitor, data storage and ZigBee network control. The system test under cold-chain logistic environment proved that it could be equipped in the whole process of the aquatic products cold-chain and the monitoring node was reliable under -18℃. The communication performance test showed that the node with a -3 dBm RF power achieved a 8.4% or lower packet loss rate within a 30 m communication distance, the energy consumption of data communication was low.

Abstract:Considering the factors of direct solar radiation, sky diffuse radiation, ground reflected radiation, outdoor air temperature, and the vehicle speed, compartment outdoor wall surface temperature function with two-order harmonic Fourier series expression was used as a boundary conditions. The effect factors of time lag, decrement, and thermal stability upon four kinds typical refrigerated trucks insulation compartment were analyzed by using combined method of thermal theory analysis and experimental validation. The analysis results show that different compartments insulation materials will cause different of time lag and decrement coefficient which increases with the increasing of the thermal inertia index and heat resistance of compartment. Different driving directions and insulation materials will cause different compartment indoor wall surface temperatures accordance with the sinusoidal variation. The compartment indoor wall surface temperature change with time closes to the compartment inner air temperature. The thermal stability inside compartment is determined by thermal resistance and thermal inertia index of insulation material. The order from the best to the worst is VIP compartment, extruded polystyrene composite compartment, polyurethane thermal insulation compartment and polystyrene insulation composite compartment. 

Abstract:The drying process of a multilayer belt dryer was modeled and simulated considering both the heat and mass transfer by C language. The data of the moisture content and temperature distributions in material bed and the air humidity and temperature profiles in air channel above material bed were obtained from the results of the simulation. The drying experiment data of garlic slices in an industrial scale dryer was obtained to verify the validation of the model. Then, based on the drying kinetic data obtained from the further simulations, the proper parameters of dryer structure and operating conditions were discussed, including belt length, number of belt layer, height of air channel, belt flip time, thickness of material bed and air velocity.

Abstract:Oat was digested into different DE values by using amylase and spray-dried to powder. The powder was evaluated in properties of packing density, repose angle, caking rate and sensory evaluation. The results showed that the powder with DE values rates above 36.2 had good dissolubility and taste, but less viscosity. At last, DE values of 35～38 was supposed as the suitable amylolytic degree for obtaining the best overall quality of spray-dried oat powder.

Abstract:To explore the storage environment and crystal structure transformation of inulin after water absorption, the hygroscopicity of inulin at 25℃, 30℃ and 45℃ were studied through static adsorption method. The crystal change was explored by using X-ray diffraction. The results showed that the moisture absorption ability of inulin was relative strong, which increased with increasing humidity and temperature. When the relative humidity of environment was 98%, the moisture absorption of inulin was 40.5% and 45.0% at 30℃ and 45℃, respectively. The values of critical relative humidity were 75.73%, 87.54% and 87.78% at 25℃, 30℃ and 45℃, respectively. The X-ray diffraction results illustrated that inulin power was an amorphous structure in dry state. The change from amorphous state to semi-crystalline state would happen during the sorption content ranged from 6.50% to 11.25% with a peak of 2θof 9.1°. The crystal inulin increased with increasing humidity when the moisture absorption was higher than 11.25%. 

Abstract:A method based on electrical parameters and support vector regression for quantitative detection of somatic cell count (SCC) was exploded. Firstly, the SCC of 100 raw milk samples was confirmed by the standard microscope counting with iodine staining. And then, an interdigitated microelectrode was used in impedance measurements of milk samples in the frequency range from 0.01 Hz to 100 kHz. An equivalent electrical circuit of the milk samples was deduced for the measured impedance data. By using of Zview software, the electrical parameters of the equivalent electrical circuit were extracted and the relationships between these electrical parameters and the degree of mastitis were analyzed. At last, based on these electrical parameters and support vector regression (SVR), a quantitative detection model of SCC was established and its feasibility was studied. It was showed that one of the electrical parameters of RS was decreased with increasing of SCC, while other electrical parameters such as Cdl－T and Cdl－P presented a nonlinear trend. The SVR model was good for prediction of SCC with high precision except the negative samples. The average relative error was 29.40%, and the bovine mastitis detection rate for 1 (sub-clinical), 2 (relative serious infection), and 3 (serious infection) level of samples were 100%. 

Abstract:The leaves of rice were captured by scanner. Integrated method combining digital image processing, parameter optimization and classification was used to explore leaves spectral and shape characteristics which were adopted to diagnose and recognize rice nitrogen nutrition. Proportion of etiolated area in the tip of leaf was extracted by method of object-oriented classification. The results of exponential regression analysis showed high correlation between tip etiolated area proportion and leaf nitrogen concentration (R2=0.863). The color indices of tip as well as whole leaves were extracted and exponential regression analysis with leaf nitrogen concentration was made, which illustrated the better performance of representation of rice nitrogen nutrition with tip information. Optimal selection of subset by means of CfsSubsetEval and Scatter search combined with support vector machine were used for pattern recognition. The result of accuracy assessment indicated that nitrogen deficiency and healthy leaves could be easily recognized and the accuracy descended with the improvement of nitrogen treatment. The accuracy of excessive nitrogen nutrition status was low. The leaf area could be a favorable assistant for recognition under deficient and healthy status. 

Abstract:Visible and near infrared reflectance (Vis/NIR) spectroscopy technique was applied to detect the disease severity of soybean pods anthracnose. Principal component analysis (PCA) combined with back propagation neural network (BPNN) and successive projections algorithm (SPA) combined with BPNN were used as two methods to analyze and prediction of the disease severity of soybean pods anthracnose. Data compression of SPA and learning ability of BPNN was used to achieve the detection of anthracnose severity on soybean pods. The accurate rate of identification was used to evaluate the model. The results of experiment showed that SPA-BPNN was the better calibration model and the accurate rate of detection was 90%. According to the results, SPA was a powerful way for the selection of effective wavelengths, and BPNN model could obtain the accurate detection. 

Abstract:The detection system for stored-grain live insects was introduced based on visible-near infrared computer vision, and the software realization of the main parts in the system was given. The near infrared images were sloped and distorted by the image registration based on projection transformation with markers. The region-growing method for identifying the live insects in the near infrared image was proposed based on the area ratio of two thresholds for connecting regions. The live insects in the visible image were located accurately by the information fusion of the multi-source images. The live insects in the visible image were located accurately by the information fusion of the multi-source images. Twenty-one global morphological features and seven local morphological features of the live insects were extracted, and the feature space was optimized to seven dimensions. The insects were classified by the classifier based on simulated annealing algorithm and support vector machine. The results showed that the recognition accuracy was 94.8% for the fifteen species of the live insects.

Abstract:Taking tomato planted in plots in spring summer greenhouse as experiment material, the correlations between maximum daily shrinkage (MDS) in tomato stem diameter and meteorological factors such as water surface evaporation Ew , daily maximum temperature Tmax , daily average temperature Tm , daily average vapor pressure deficit DVPDm , midday vapor pressure deficit DVPDmd , daily total radiation Rs and daily maximum radiation Rmax were studied by using path analysis method. The results indicated that the direct path coefficients between Rmax ,DVPDm , Ew and MDS were all positive. The Rmax’s coefficient is the highest and the DVPDm’s coefficient is the second. The correlations between MDS and Rmax , DVPDmwere significant, but the correlation between MDS and Ew was not significant. Therefore, the Rmax and DVPDm were decision variables which controlled tomato stem diameter variation directly in greenhouse. In addition, the direct path coefficients between Tmax, Tm , DVPDmd ,Rs and MDS were all negative, but their sum coefficients between direct and indirect path coefficients were all positive. Tmax ,Tm , DVPDm ,Rs had indirect influence on tomato stem diameter variation through Rmax and DVPDm . Based on this conclusion, the simulating equation between MDS and Rmax , DVPDm was established which was significant through test, and the calculated values of MDS could reflect its observed values exactly. 

Abstract:For providing traceable farm production, a data automatic processing system for egg production was designed and implemented, which altered frequency of acquisition based on time. Java media framework was used as the main model to acquire and process massive image and sound datasets. The system could not only acquire and save synchronized environmental, image and sound data, but also significantly reduce storage space and costs, and speed up query speeds. Tests show that image and sound data in one day is only 200～400 MB, and collected data in one year is about 70~140 GB, yet contains most of the scenes of the production process.

Abstract:The concept of dividing point between configuration and variant design was proposed firstly. An optimization objective function was constructed by combining product performance and the customer satisfaction. A judging method was designed with a performance index for checking the dividing point and performance similarity for finding the parts of required variant design. Then, with the objectives of optimal product performance, a multi-objective optimization algorithm was designed based on genetic algorithm, and the process of checking the dividing point was also specified. In the end, the proposed genetic algorithm was verified by an example. The results showed that the proposed approach could solve this problem efficiency. 

Abstract:The dynamic modeling and slide-mode control for a planar macro-micro parallel robot were investigated. Firstly, the inverse position and the forward position were analyzed by vector method. The velocities and accelerations of the mechanism were derived. Then, pivotal points were selected. The partial velocity and angular velocity about these ones were obtained. The inertial force and moment of the links were obtained by Newton-Euler formulation. Furthermore, based on the principle of virtual work, the dynamic formulation of the system with micro-driven table was formulated. Finally, a sliding-mode controller was designed. The result showed that proposed method was effective. 

Abstract:Due to the requirement of multi-dimensional nanometer level positioning of the compliant precision mechanism, a piezo-driven spatial compliant parallel mechanism was presented through the conventional Delta parallel mechanism. The inverse kinematics was developed on the basis of the Pseudo-Rigid-Body (PRB) model. After the simplifying of the mass of passive arm and calculating the strain energy of the flexure hinges, the dynamic equation was established through the Lagrangian approach, and the natural frequencies are evaluated by utilizing the geometric parameters. Three natural frequency errors, which were along with three primary translation directions, between the experiment results and the theoretical analysis were 12.71%，12.14% and 14.90%. The error between the finite element simulation and the theoretical results were 6.20%，5.66% and 10.28%. The results also showed that the simplified process during the theoretical analysis was reasonable and the derived mathematics model was creditable.

Abstract:The inverse and forward position model of a 3-SPR parallel platform mechanism was established. The velocity model of each chain was derived on basis of the position analysis. By comparing the calculation analysis of samples and the results derived by simulation software CosmosMotion, the position and velocity analyses were proved to be correct. The virtual mechanism was modeled by using SolidWorks. The geometric shape of workplace was obtained. 

Abstract:The dynamic model of tooth meshing process for gear transmission system was proposed. The vibration differential equation by considering time-varying mesh stiffness, tooth face wear and errors was set up. The analysis method of dynamic load spectrum in gear transmission system was studied. The time domain, frequency domain and time-frequency domains of vibration characteristic were analyzed. These results were compared with numerical simulation and experimental results. It is shown that the proposed method consists with the numerical simulation and experimental method.

Abstract:A method of 3-D tolerance modeling and analysis for operation removal model was proposed based on operation feature recognition. The roughcast was considered as the assembly of part model and operation removal models. Small displacement torsor (SDT) theory was used to describe design and process tolerances while the changeable constrains of tolerance torsors were calculated. The tolerance network graph of the operation removal models was constructed and the tolerance propagation mechanism in the tolerance network was discussed. Then the process tolerance stack-up models were achieved, which was the basis of process tolerance allocation. Finally, a case was analyzed to verify the validity of the proposed theory. The process tolerance allocating method based on the proposed theory was mentioned briefly.

Abstract:The grinding force curve always varied as convex in the surface grinding hardening thin workpiece. The workpiece became concavity on the ground profile. Through coupled thermal-mechanical FEM analysis, the variation of grinding magnitude caused by the grinding deformation was the main reason for grinding force variation. The mode of workpiece clamping exerted tremendous influence on the deformation. The grinding force variation affected the heat flux into the workpiece and the grinding temperature. As a result, the grinding depth is non-uniform. Through the relationship among the grinding force, grinding temperature and the grinding thermal deformation，the grinding force can be divided into intervals and be iterated. The predictable grinding force curve has good agreement with the experiment result and is useful to analyze the grinding hardening depth distribution. 