Abstract:Both tire contact point and wheel center is changed with rightward and leftward of vehicle steering by the effect of geometry of steering axis. It’s benefit to calculate steering axis geometry by wheel movement for suspension design. A vehicle suspension Kinematics and Compliance (KnC) facility was used to get steering test data, such as kingpin inclination angle, caster angle, caster trail, scrub radius, spindle trail and kingpin offset at wheel center. The method was validated by the simulating result of Adams and test data, and errors were within the allowable range. The solution method met the requirement.

Abstract:The yaw stability control of 4WID-4WIS vehicle was studied. The coupling relationship between vehicle side slip angle and yaw rate was analyzed. A fuzzy yaw stability controller composed of active front steering (AFS), active rear steering (ARS) and direct yaw moment control (DYC) was designed based on the following strategy—when side slip angle was small, the main aim was to follow the anticipant yaw rate, and when side slip angle was big, the main aim was to reduce vehicle side slip angle. Simulations results indicated that compared with vehicle controlled by DYC, vehicle controlled by AFS+ARS+DYC (RFD) reduced the braking tore and longitudinal slipping rate obviously, which ensured the vehicle yaw stability with high speed on low friction road.

Abstract:Separation of software development and hardware development, and the lack of open in software, are all shortcomings of traditional embedded system. A comprehensive solution using software/hardware co-design and the quantum framework was presented and applied to AMT electrical control system design. Thus, a comprehensive development framework of “five layers/three buses/one framework” was formed. The embedded vanilla kernel was selected, and the quantum framework port about vanilla kernel and Nios Ⅱ was given, as well as the designed main active object’s HSM, which was more suitable than finite state machine for AMT system. 

Abstract:In order to quickly and accurately identify the guidance line in complex environment, a line recognition algorithm based on prior knowledge was proposed. Images were divided into several regions by field range and line characteristic. Both means of full image and region were used to make adaptive threshold of each region. Scanning mode was decided by information of previous image, then noises were filtered and intermediate points were acquired. An improved Hough transformation with search angle limitation and nonuniform sampling was applied to localize guidance line. Finally cross ratio theorem was used to calibrate the parameters. The experimental result showed the method was characterized by robustness and real-time, the average computing time was about 90ms for each image.

Abstract:Based on ADAMS and NASTRAN, a rigid-flexible coupling dynamic full vehicle model was established. A virtual test rig was also built up by using ADAMS/Vibration to analyze the vibration responses and transfer characteristics of the suspension system motivated by middle-high frequency road excitations. To improve the vibration isolation capability of the suspension system，the effects of the subframe, twist beam and rubber bushings of the chassis/suspension system with the vehicle vibration was analyzed. Finally, through adopting the ADAMS/Insight DOE technology, the researchers proposed the sensitivity analyses of several key rubber bushing stiffness, and the optimization of the bushing in the environment of ADAMS/Insight. By changing the bushing stiffness, the vibration performance of the vehicle was improved. Simulation results indicated that the vertical acceleration root mean square (RMS) decreased from 477.9 mm/s2 to 454.2 mm/s2 , by 5% in the whole research frequency spectrum.

Abstract:Aiming at the problem of error between the actual value and estimated value of engine’s dynamic torque, as well as HEV’s energy control strategy cannot be executed accurately. Taken parallel-serial HEV as an example, the parameters of power coupling mechanism were analyzed. Planet gear power coupling mechanism’s dynamics characteristic and efficiency characteristic were applied to deduce the algorithm of engine output torque calculation method for parallelserial HEV. The experiment results showed that the maximum relative error of engine dynamic torque between theory calculating and experiment testing was decreased from 5%~8% to 3.94%. 

Abstract:To increase the torque capacity, the torque-transferring formula was deduced from electromagnetic force theory of virtual displacement according to working mechanism of magnetic particle clutch. The FEM model was established based on theory of Maxwell equation for analysis magnetic field and its simulation results conformed to the test results. According to the simulation results, improved design was made on magnetic particle clutch. The results showed that the improved magnetic particle clutch had a remarkable effect on the torque performance, and its torque performance increased by 45%.

Abstract:An optimization model for load sensing hydraulic excavator was established, in which the largest flow areas of hydraulic multi-way valves were taken as main design variables and working cycle time was taken as the main objective while the other design requirements were used as main constraint conditions. An optimizing example was presented. The result showed that the cycle time was reduced from 14.04 s to 12.61 s. Meanwhile, most of the other performance indexes were also improved. The largest optimized digging force of bucket cylinder and arm cylinder were increased by 4.38 kN and 3.61 kN, respectively. The largest digging height and the largest digging radius were increased by 189 mm and 37 mm, respectively. The generalized optimization of entire system and overall performance for excavator was realized.

Abstract:The plough surface was re-formed by using Pro/E’s functions based on measured points, which were scaled with 3-D coordinate scale instrument. And then ANSYS/LS-DYNA software was used to carry out the turning dynamics simulation of the tilling plough. The direction of soil velocity was vertical to the surface of plough, and its distribution was like radiating. The distribution of equivalent stress was like isoline, and the data was becoming smaller from the contact point to outer. The results of simulation were verified by the data of experiments in soil bin.

Abstract:According to the problems of few available no-till seeders and residues-blocking and bed-damaging during the seeding of wheat in maize residues cover fields in permanent raised beds (PRB) in northwest oasis farming areas, the new anti-blocking (residue-chopping and throwing by powered L-type hammering blade and residue-cutting by knife type opener) and bed renovation (bed-reshaping by double-wing plough) ideas were put forward. The powered hammering blade no-till wheat seeder for PRB was designed. The key parameters for L-type hammering blade, opener and double-wing plough were determined. The experiment in maize residue cover fields showed that the seeder was effective in solving residues blocking. Compared with 2BMF-5 no-till wheat seeder, the spring wheat yield was similar and bed renovation effect was better with the decreased soil disturbance. 

Abstract:Work principle of a new anti-blocking mechanism for no-till planting was described. Equations about the trajectory, the absolute velocity and the acceleration of any vertex on the finger wheel were deduced. Associated graphics were constructed by software, and parameters of the device were analyzed. The results indicated that the movement angles δ was chosen between 20°～40°and had great influence on working width compared with radius of the finger wheel. Backward inclined distribution should be adopted for the finger. 

Abstract:A soil-gashing and root-cutting mechanism was designed and tested in order to improve degenerated Leymus-chinensis grassland in China. The mechanism had eight equally-spaced sets of cutting blades on a blade shaft, and each set consisted of 3 blades. These blades were keyed on the blade shaft as double-helical arrangement through flange hubs. The blade on the shaft was powered by a final drive which was driven by a universal shaft connected to the tractor PTO. Cutting depth was controlled from 100mm to 200mm by two gauge wheels mounted on the rear end of the tool frame. Field experiment indicated that the mechanism could cut consecutive slits in compacted top soil. The maximum cutting depth was 205mm and the average width of slits was below 13mm. No soil overturning and vegetation destruction were observed. Because the slits cut by the mechanism provided soil aeration and promoted the growth of Leymus-chinensis, the soil bulk density decreased and crop yield increased by nearly double in the second year of soilgashing and rootcutting treatment.

Abstract:提出了双滚筒气力循环式花生脱壳机总体结构方案、二次循环脱壳与气力输送工作原理，进行了双滚筒脱壳装置、清选装置和传动系统等关键工作部件的结构设计。双滚筒脱壳装置由直径、转速不同的一次脱壳滚筒和二次脱壳滚筒以及各自的凹板筛构成；清选装置主要由振动筛和风机组成。花生脱壳试验结果表明：适宜含水率下花育23品种花生，在一次脱壳滚筒和二次脱壳滚筒转速分别为296、392r/min时，花生脱壳综合性能指标最优，即花生脱净率为99.12%，花生仁破碎率为1.82%，花生仁损失率为0.40%。

Abstract:For the randomness and uncertainty of seed movement in sowing process of the clamping dibbler, high-speed photography technique was used to analyze the operating process of the improved clamping dibber. The seeds in seed-collecting area could make two seeds circulation movements flows, which could make twice scouring seed-filling, and the seed speed relative to the seed-room was greater than unimproved dibbler, so the probability of seed-filling was increased. The main reason leading to seed-missing of seed-collecting devices was that two seeds were placed in parallel in the seed-clamping mouth. There were three ways to achieve seed-cleaning operation, one was that seeds fall under the action of gravity, another was that seeds were squeezed out the seedclamping mouth with the seed-clamping mouth litter, and the third was that seeds fall due to the equilibrium position of seeds disappear as the dibbler rotating. The average velocity of seeds entering the seed-clamping mouth decreased gradually with increasing of dibbler rotational speed. The findings were beneficial to comprehend the working process of dibbler microscopically.

Abstract:Rice seeds motion on a vibrating plate was simulated using discrete element method software EDEM. The mechanical interaction forces, both between seed and the plate and among the seeds were modeled by Hertz-Mindlin (no slip). With the variation of vibration frequency, amplitude and seeds initial thickness, their effects on the seeds spatial distribution were analyzed. The simulation area was divided into uniform layers in vertical direction and the seeds spatial distribution in layers at different time was obtained. The simulation results showed that with the plate vibration frequency of 11~12Hz, vibration amplitude of 12~13mm and seeds initial layer number of 3~5, the ideal seeds spatial distribution which was beneficial to improve suction precision could be received. Plate vibration frequency, vibration amplitude, seeds initial thickness and sucking distance were selected as influencing factors, then orthogonal experiments were carried out on test-rig and results indicated that the precision suction ratio was greater than 93% with the plate vibration frequency of 11Hz, vibration amplitude of 12mm and seeds initial layer number of 4.

Abstract:The process of rice seedlings passing through the separating chutes was observed using high speed photography technology. The circular arc part of chutes was the key that affects the rice seedlings passing through chutes. It was easier for rice seedlings to pass chute No.4~7 than No.1~3. The time of rice seedlings passing through chutes was shorter and closed to simulation results calculated by computer when water content of nutrient soil of rice seedlings was 26.6%. It need the longest time when rice seedlings pass through chute No.1. The shortest time appeared when rice seedlings passing through chute No.6. The results of experiment showed that chutes of separating rice seedlings could be satisfied the requirements of throwing transplant machine for rice seedlings sprouted in the plastic cell-tray. 

Abstract:Temperature field analysis of water immersion temperature rice seed soaking germination equipment was analyzed by finite element method. Simulation analysis showed the highest temperature during soaking appeard in the edge of rice in contact with water. The lowest temperature appeared in the center of rice seed. With the increasing of germination time, the heat transferd to the center of rice seed continuedly. The center temperature reached to 25℃ and the highest temperature reached to 31℃ after 23h, then the temperature of rice seed reached to the optimum tempreture of 25~31℃. Experiment result was consistent with the simulation results.

Abstract:Aimed at homogeneity principle of water mix with pesticide in the jetmixing apparatus, a mathematical model for solving the interior concentration field was established, CFD software called Fluent was used to calculate the field. Timeaverage mass fraction of pesticide was obtained. Intensity of segregation was introduced to quantitative evaluate the mix degree of water and pesticide. The water was mixed with pesticide uniformly when intensity of segregation was 0.05. As the increasing of area ratio, the shortest mixing distance decreased with the area ratio m∈［2.56,4.00］. The mixing performance of jet-apparatus with m=3.06 was better than the jet-mixing apparatus with m=2.56 and m=4.00. The diffusive mixing zone appeared after the maximum turbulent intensity average rate decreased by 14.96%. And the coordinate interval was X∈［(-13.85m+111.37)mm，116.5mm］.Therefor,when measure the concentration in jetmixing apparatus by experiment, it should according the coordinate interval and area ratio to choose the appreciate concentration measurement point.

Abstract:Guided baffle shield application is effective and economical method to reduce droplets drift. The performance research of this system was carried out with wind tunnel experiment and field trials of herbicide.The results showed that the optimum structure parameters of the guided baffle shield sprayer were: shield width of 40cm, shield angle of 50°, nozzle angle of 50°. 30 days after herbicide application, the weeds control effects was 81.4%, fresh weight effects was 76.4% which were superior to conventional application; when the herbicide dosage reduced by 20%, the effect with shield application was same to conventional application. So the guided shield application could save pesticide and reduce cost. 

Abstract:In order to make the research on the design of locusts’ LED trapping light and digital control of induced light field by utilizing LED light source and homemade phototactic behavior trial equipment, the comparative tests of locusts’ phototactic behavior for the choice of purple light, purple-blue-green light in different time periods were carried out by adopting contrast experimental method. The reason affecting locusts’ phototactic behavior was analyzed. The results suggested that locusts’ phototactic choosing behavior was relevant with spectrum, illuminance gradient, internal biological features and environmental factors under the same illuminance gradient. Locusts’ phototactic behavior choosing purple light was higher than purple-blue-green, under the different illuminance gradient. Locusts tended to select the stronger illuminance gradient. When the illuminance gradient of purple-blue-green was 10 times higher than purple light, locusts’ selective response to purple-blue-green light was superior to purple light. Locusts’ internal biological features and environmental factors restricted the increasing effect of locusts’ phototactic behavior by improving light intensity in the different time periods. The sensitive degree of locusts’ phototactic response to purple light as well as purple-blue-green light at night was different, locusts’ phototactic behavior showed that locusts’ phototactic sensitive critical point, the optimal and the best range of light illuminance values, locusts responding to purple light as well as purple-blue-green light in the different time periods of night, was different.

Abstract:The working process of combine harvester was analyzed, aiming at the properties of nonlinear, time varying and delay. Fuzzy control with grey prediction algorithm was used to control the speed of combine harvester and keep the load stable. The necessity and importance of the combining predictive control with fuzzy control was analyzed. Forward speed control device for combine harvester based on grey prediction fuzzy control was designed. The grey prediction fuzzy control model was established, simulated and tested. The results showed that the control system with the grey prediction fuzzy control algorithm had shorter adjustment time, smaller overshoot and more superior control performance. 

Abstract:To avoid crashing into people going through the rail or other obstacles and improving the system’s safety and stability, an obstacle avoiding system of mountain orchard steel wire rope traction cargo vehicle was designed. The system was composed of STC single-chip micro-controller, ultra-sonic range measurement modules, infrared detection unit, wireless communication module, voice alarm and manual control module. The system was designed to achieve an obstacle detection distance of no less than 150 cm and a 100% successful braking rate. System verification test results indicated that: when using static obstacle, the minimum vehicle-to-obstacle distance was 100 cm after uphill brake and the minimum vehicle-to-obstacle distance was 90 cm after downhill brake. When using motion obstacle, the minimum vehicle-to-obstacle distance and time delay were 98 cm and 0.64 s, respectively after uphill brake. The minimum vehicle-to-obstacle distance and time delay were 66 cm and 1.30 s after downhill brake.

Abstract:Modeling of organic matter degradation and thermal balance were built based on the first order assumption with respect to the quantity of biodegradable volatile solid (BVS) and the law of thermal conservation during composting. Different kinds of organic matter were mainly degraded in different composting stages. For the organic matter degradation model, temperature, moisture content, oxygen content and free air space were considered as key influence factors to degeneration rate. For the model of thermal balance, forced convention and conduction were considered as the main heat removal form. In order to verify the constructed models, an aerobic composting process of pig slurry was conducted. Temperature, oxygen content, moisture content and organic matter concentration were all monitored in the process of composting. The results could be helpful for guiding composting process operation. 

Abstract:It is important to realize rapid detection of straw content in co-firing biomass-coal blends for drawing up reasonable precept about biomass co-firing power generation subsidy. The original samples were consisted of 81 straws and 9 coals collected from different regions and different varieties in China. 90 blends samples of coal and straw (1%～30%) were prepared after comminution and separated into a calibration set (60 samples) and an independent validation set (30 samples). Spectra were scanned by FT-NIR spectrometer. The interval partial least squares (iPLS) and the genetic algorithm (GA) were used for wavelength selection. Quantitative analysis models for straw content were established by partial least squares (PLS). The results showed that data points for modelling decreased from 3001 to 33, determination coefficient, standard deviation of prediction (SEP) and ratio of performance to standard deviation (RPD) in validation were 0.89, 2.87% and 3.06 by GA-PLS method, respectively. It is concluded that NIRS with GA-PLS was feasible for fast quantitative analysis of the straw content in co-firing biomass-coal blends. 

Abstract:In order to reduce the sensing data transfer frequency and node energy consumption in real-time cold-chain logistics monitoring system for agri-food based on wireless sensor networks, a sensing data compression method based on statistics process control was presented. The D-X-RS algorithm that fits for the sensor nodes’ data processing capability was designed. The data compression performance of D-X-RS algorithm, threshold algorithm and K-means algorithm by cold-chain logistics environmental simulation in laboratory was compared. The result showed that the compression cost per point (CCP) of D-X-RS algorithm was close to the best algorithm both in temperature fluctuation and steady states. The algorithm had good balance and flexibility. 

Abstract:Mathematical model of mass and heat transfer about vacuum infrared radiation drying on Rehmanniae was built based on Fourier equation and Fick equation. The values or equation of model parameters were determined by theoretical analysis and experiments. By using finite difference method, mathematical simulations of sample temperature and moisture content under different drying conditions were carried out. The results showed that values of simulation and experiment fit well, the model could well simulate the changes of sample temperature and moisture content during drying and the influence of drying parameters on drying characteristics were illustrated by the model satisfactorily. 

Abstract:A pulsed air-impingement dryer was designed with large processing capacity, convenient to replace the size and shape of the nozzle exit compared to conventional air-impingement dryer. The machine could adjust air temperature, wind speed, rotary speed of materiel shelf, nozzle diameter and structure according to different materials properties. Material was received the pulsed impact of high-speed hot air, which contributed to outward migration of moisture within the material. Tomato was adopted to test the performance of pulsed air-impingement dryer. The results showed that the dehydration intensity and processing capacity of pulsed air-impingement dryer was improved than the conventional air-impingement dryer.

Abstract:A high-speed camera was used to investigate the flow pattern of liquid film. Four regimes were identified as: droplet flow, strand flow, discontinuous film flow and continuous film flow when liquid flow rate increased gradually. Moreover, the critical flow rate of water, ethanol, ethylene glycol and glycerin solution under different rotate speeds were tested. Then the Gaussian process was adopted to predict more data. Results indicated that the critical flow rate increased with the growth of surface tension and decreased as the viscosity increased at certain rotate rate.

Abstract:A test was applied to determine the heat transfer coefficients of apple and cucumber to obtain the experimental correlation of heat transfer. The results showed that the heat transfer coefficients of fruit increased with the increasing of air velocity, decreased with the increasing of radial dimension of fruit under the same condition of the hot air temperature. The heat exchange efficiency between fruits and hot air was enhanced significantly for the biological transpiration. Phase transition occurred in the process of heat transfer.

Abstract:Nondestructive detection of apple mealiness was investigated by using neighborhood rough set theory and hyperspectral scattering image technology. Spectral scattering profiles between 600nm and 1000nm were acquired by hyperspectral scattering image system for 576 apple samples. The optimal wavelength sets were chosen from 81 raw characteristic attributes by neighborhood rough set. 526 samples were selected randomly for calibration set and 50 samples were selected for validation set to develop classification model using optimal wavelengths coupled with support vector machine (SVM). Simulation was repeated 10 times to investigate the ability of classification model. Results showed that neighborhood rough set could select 14 optimal wavelengths effectively. The validation model using 14 optimal wavelengths yielded better result (classification accuracy 75%) than the full spectrum model (classification accuracy 71%) and the principle component analysis algorithm (classification accuracy 74%).

Abstract:In order to evaluate the ability of near infrared spectroscopy (NIRS) to detect moldy core in apple fruits, the discriminant efficiency of Fisher function based on several spectra preprocessing methods and principal component analysis (PCA) were investigated. Results showed that the discriminant efficiency of Fisher function established by 20 principal components (PCs) after vector normalization preprocess was the highest, discriminant efficiency for training sample set and test set were 89.9% and 87.8%, respectively.

Abstract:Competitive adaptive reweighted sampling (CARS) method was employed to improve the prediction accuracy of the NIR quantitative model of four kinds of fatty acid (palmitic acid, stearic acid, oleic acid and linoleic acid) in edible oil．Predict concentration residual method was employed to detect the outlier before preprocessing the spectroscopy by normalization．The key variables were selected by CARS method．The partial least squares (PLS) calibration models of four kinds of fatty acid were established respectively in the optimal conditions，and compared with the results using OPUS software. Determination coefficient (R2 )，root mean square error of cross validation(RMSECV)and root mean square error of prediction(RMSEP)were used to evaluate the quality of the modes．The results showed that better prediction was obtained by CARS. The result showed that using CARS could effectively simplify the model and the less number of wavelength variables selected could be reference for developing filter spectrometer of edible oil. 

Abstract:A mechanical model of a cell was established by using finite element technique to study mechanical behavior of the cell on condition that the plant was water stressed. Based on the biophysical equation, the change of the turgor pressure in cell caused by transpiration was obtained. Then the dynamics equation of turgor pressure was got. The result showed the relation between the turgor pressure and the deformation of the cell. The results also showed that the radius of the cell decreased from 3.55×10-5 m to 2.42×10-5 m nonlinearly when the turgor pressure changed from 200 kPa to 120 kPa linearly; and the deformation was influenced by material mechanical parameter of cell wall. The radius of the cell was 3.58×10-5 m，3.30×10-5 m，3.13×10-5 m respectively as the Mooney-Rivlin constant (C1) was 0.7 MPa， 1.0 MPa，1.5 MPa when the turgor pressure was 200kPa; the radius of the cell was 1.41×10-5 m，1.22×10-5 m，1.10×10-5 m. respectively as the Mooney-Rivlin constant (C2) was 0.10 MPa，0.15 MPa，0.20 MPa when the turgor pressure was 200 kPa. 

Abstract:Based on relationship between phosphors uptake, partitioning, radiation and temperature, a simulation model of greenhouse cucumber phosphorus uptake and partitioning was established. Different experiment data was used to validate the model. The results showed that the coefficients of determination between predicted and measured value based on the 1∶1 line were 0.91,0.74,0.65,0.72,0.65, respectively, and the root mean squared error between the predicted and the measured value was 0.04g/plant, 0.03%, 0.04%, 0.02%, 0.06%, respectively, for phosphorus uptake, root, stem, leaf and fruit phosphorus content. The model could give satisfactory prediction of phosphorus uptake and root, stem, leaf and fruit phosphorus content of greenhouse cucumber in different seasons.

Abstract:The integral structure of the multi-span plastic greenhouse was taken as the research subject, and influence of film-preload on ultimate bearing capacity of the multi-span plastic greenhouse was studied through physical model test and finite element analysis. By using ANSYS 10.0, firstly, temperature load was performed to numerically simulate preload, the computational models of greenhouse structure on six kinds of film-preloads condition were established by imposing temperature load. Then, dual nonlinear analysis to the computational model of greenhouse structure was given on snow load condition. Therefore, ultimate bearing capacity was confirmed by racing the balance path of the loading-displacement curve. According to analyze loading-displacement curve, influence of the film-preload on ultimate bearing capacity could be researched. It could be concluded that film-preload would not affect the integral structural buckling mode of multi-span plastic greenhouse, but would reduce ultimate bearing capacity of greenhouse structure by 17%~63%. 

Abstract:In order to achieve high efficient nitrogen removal from high ammoniumnitrogen swine wastewater, sequencing batch reactor activated sludge process (SBR) was used to treat swine wastewater to the phenomenon which the urea (mainly from pig urine) hydrolysis of swine wastewater was accompanied by changes of pH value. Under conditions of normal temperature (20℃) and non-restricted dissolved oxygen, effects of pH value and aeration time on ammonium removal, characteristics of shortcut nitrification were studied. The results showed that nitrite accumulation rate was 75%～80% when pH value was 7.0～9.5. Shortcut nitrification would not affected by long-term aeration. In the biological treatment process of high ammonium-nitrogen wastewater concentration, the nitrite accumulation was related to levels of pH value, free ammonia (FA) and free nitrite (FNA) in influent.

Abstract:Aiming at the characteristics of complex, time-delay and gain time-variation of agricultural robot steering system, the Adaline neural network (ANN) was applied to internal model control (IMC). An adaptive- control method for time-delay online adjusting and gain control was proposed. An algorithm based on Adaline neural networks could adjust time-delay and gain adaptively, and overcome effects of time-variation parameters on IMC and plant model by online optimizing feedback error. Simulations and experimental results verified that compared to conventional PID control method, the proposed control method possessed the advantage of high precision, great adaptability and robustness, so it is feasible for agricultural robot steering system.

Abstract:For the problem of difficulty to guarantee products assembly process reliability, reliability-driven modeling approach of the assembly process was presented based on grey system theory and polychromatic sets theory. A method was described to determine the major assembly process step to public the reliability. Impact factors of each working step were analyzed. The methods to establish the relationship matrix between the various factors and the process step and to determine the main factors of the assembly reliability were elaborated. The control measures for reliability of the main factors were proposed. The purpose of reliability-driven for assembly process was achieved by above methods. An example of controlling assembly process for a machining center NC rotary table reliability-driven showed the feasibility of the method.

Abstract:The differential equation of motion of the Delta parallel robot flexible component was established by the finite element theory, the mechanisms dynamics model was gained by combining the kinematic characteristics and specifying the direction of the node displacement. The real motion of mechanism was regarded as the superposition of the nominal motion and elastic vibration. The position and direction error of the moving platform was regarded as the perturbation of nominal motion. The relation equation of configuration error and node displacement of moving platform was obtained. In the example, the characteristic of modal frequency of mechanism in the workspace was gained by considering the gravity, inertial force and damping dynamic response under the action. The 6-D error of the moving platform was evaluated comprehensively.

Abstract:A hydraulic motor with digital distribution mechanism based on high speed solenoid valves (HSV) was introduced. Firstly, the operating principle and the structure characteristics of the proposed hydraulic motor were described. Then, the mathematical model of the proposed hydraulic motor was established according to the distribution process for counterclockwise and clockwise rotation by analyzing the piston dynamics of each plunger. The differences of the two distribution process were analyzed. The related simulation was conducted and the direction changing process of the proposed hydraulic motor was studied. The experiments were carried out to validate the effectiveness of the simulation results. Finally, the influence of the frequency of HSV was discussed and the performance was compared between the proposed motor and the traditional one. 

Abstract:Applying the theories of Hertz contact, tribology, gear engagement and heat transfer, the planetary gear was taken as study object, the variation of sliding velocity and friction coefficient was investigated and the contact stress along the contact path was conducted. Heat transfer coefficient of gear end face and teeth surface and heat flux at different engaging positions were calculated. 3-D finite element models of gear teeth were established to predict stead temperature field. The influence of standard and modified profiles on temperature field and contact pressure was evaluated. Based on the results of stead thermal analysis, distribution of transient temperature field was investigated by using finite element method. 

Abstract:A modified contact model of joint interfaces based on fractal theory was proposed. Furthermore, numerical simulation was carried out to obtain the complicated nonlinear relations between normal contact stiffness and the normal contact load、the fractal dimension D and the fractal characteristic length scale parameter G. The results showed that the normal contact stiffness increased with the normal load, decreased with G but complicatedly with D. The results showed that the contact model could be used to calculate the normal contact stiffness and the normal load.

Abstract:Thread form showed distortion when measuring parallel screw thread parameters by using non-contact method. The traditional way had some defects, such as time consuming, skilled operator, high-precision equipment for adjustment and so on. Hence, a method through digital image calibration was presented. Based on the thread geometrical principle, the mathematical model was given out. With the above thread mathematic model, images obtained from camera were corrected and real thread form could be got. With the results of related experiments and simulation, the mathematic model was certified. This proposed method could improve accuracy and efficiency of thread measurement and detection.

Abstract:Based on benchmark cylindrical cup deep drawing scheme, a cylinder deep drawing scheme was designed to study deep drawability of the high strength steel (HSS) sheet . HSS sheet SPCN440W-NS (1.2mm) was drawn respectively under 70kN and 10kN blank holder force (BHF) conditions, and drawing process was simulated by DYNAFORM software. The test and simulation results showed that HSS sheet SPCN440W-NS had better deep drawability. BHF had great influence on deep drawability of the HSS sheet. Workpiece had better surface quality under 70kN BHF condition, and was easily wrinkled in its flange region under 10kN BHF condition. The simulation accuracy of the DYNAFORM software under 70kN BHF condition was higher than 10kN BHF condition.