Abstract:A electromagnetic power-split (EMPS) hybrid electric vehicle was designed. This system with dual-rotor brush motor could be used to modulate the engine power flow, also can be used as electromagnetic clutch and CVT. The system configuration, working principle, the vehicle control mode and etc were analyzed. The control mode was tested under the NEDC based on the vehicle simulation platform. The dynamic and economic performances of the EMPS HEV were analyzed. The results noted that the designed vehicle control mode of the EMPS HEV worked properly under different cycles. The results also noted that the time from 0 km/h to 100 km/h was 12 s and climbing grade was bigger than 17°, these values were all satisfied with vehicle dynamic target. The average fuel consumption under the NEDC was 4.75 L/(100 km), the fuel can be saved was 41.3% compared with the related conventional vehicle. 

Abstract:The qualitative analysis of system power flow was made for articulated vehicle which had six independently-electric-driving wheels running in parallel under different driving states without following control. The system power flow model and wheel-motor power matrix were established. System power flow was described by using power bond graph and normalized power matrix. Taking torque as the control target, the test was performed to simulate the power flow state of permanent magnet synchronous motors running in parallel by means of adjusting voltage. Test analysis showed that the traction and braking power of the wheel-motor on both sides were equal when driving and electric braking straightly. The outside wheel-motors ran into regeneration state and produced braking torque when steering angle was large, then inside wheel-motors’ load were aggravating and theirs slip ratio increased. Speed ratio kn increased with the increasing of steering angle, but power ratio kP decreased at the same time. The severity of load had little effect on kn, Torque ratio kT of the rear axle was larger than the front axle and overload state was larger than light load state. 

Abstract:The elasto-hydrodynamic lubrication theory was used for setting up transmission characteristics of traction calculation model. The dynamic simulation model of this system was established by using Matlab. From simulation results, traction friction pair was equivalent to traditional role of main gearbox or torque converter with a buffer function in the transmission process. When gave a input speed and a loading force, the smaller the speed ratio was, the greater the output speed was. But the time of achieving stabilization was longer at the same time, the response time of output torque and output angular acceleration was longer. The simulation results reflected the dynamics characteristic of traction transmission devices. It is provided an accurate method for hydraulic clamp traction transmission devices.

Abstract:In order to obtain better robustness and real-time processing of path recognition, the binary segmentation image, noise searching and filtering procedures were employed. The whole path was classified into far part and near part, and the difference between the two parts was used as a threshold for selecting target road. So the navigating parameters were adapted to the changing path. Based on a model of four-wheel intelligent vehicle, a path tracking simulation was performed. Then, the navigation system based on path tracking was designed by using two digital signal processors. The experiments showed the accuracy and robustness of the system.

Abstract:In order to meet the control reliability requirement of hybrid vehicle electronic shift handle signal, based on analyzing the structure and signal control logic of the handle, the reliable control method was designed by signal processing and strategy redundancy algorithm. Through the establishment of the system control model with Simulink and the usage of rapid control prototyping approach with MotoTron, the control method of the shift handle signal was tested to verify its reliability. Test results showed that the control method could meet the shifting demand for hybrid vehicle, and the control reliability of the shift handle signal and traffic safety could be ensured. 

Abstract:Multi-parameter integrated control method was proposed. Multi-parameter variation’s characteristics were integrated into one parameter to update the control parameters of torque algorithm real-timely. This multi-parameter integrated method was on the base of all states experiment of the motor and online search. It made full account of multi-parameter’s nonlinear behavior. Experimental results verified that not only the precise torque control of maximum torque-per-ampere in the low speed, but also the precise torque control in the flux-weakening of high speed were carried out, which met the requirements of the electric vehicle applications.

Abstract:An inter-row tillage machine was developed with standing stubble. Tillage operations were performed in the ridges and furrows alternately which can be used for inter-row shallow-tillage, ridge stubble-breaking or full-width tillage operation through the rational arrangement of blades on the rotor and disassembling in the blades, or one machine for three purposes. The experiments showed that this machine met all the agrotechnical requirements in the three operational states. The determination results of soil compaction caused by the tractor tyres in the inter-row shallow-tillage operation showed that soil compaction had a significant effect on the soil bulk density at the depth of 0～10 cm. The soil bulk density increased by 8.5%, 7.0% and 6.2% when the machine traveled at speeds of 0.50 m/s, 0.65 m/sand 0.92 m/s, respectively. Soil compaction had little effect on the soil bulk density at the depth of 10～20 cm. Soil compaction also caused an increase in the torque of the blade when cutting the soil, but the increase in torque was not significant. 

Abstract:The kinematics model was established for the rotating disc of intra-row weeding robot, and the trajectory of the rotating disc was designed by simulating its working process. Then the virtual orthogonal experiment was made in different factors and different levels. In order to optimize the best operational parameters in combination, the effects of weeding performances of the rotating disc in diverse parameters were analyzed by taking the coverage rate and the inbreaking rate as evaluation indexes. The experiment results verified that the simulation and orthogonal experiment were accurate and efficient with a good operation effectiveness of the prototype, and the weeding rate reached to 88.5%, yet the wounded seedling rate was only 1.6%. 

Abstract:The remote control spray system based on the helicopter from German VARIO company was designed. The spray system including the tank, control box, pump, pipeline system, cantilever and centrifugal nozzle were set on un-manned helicopter. The remote control system reserved for aerial spraying was developed. The spraying system can be operated by remote control units. By carrying out the theory research on main influence facts of centrifugal atomizing spray effect and the tests for nozzle performance, the optimal operating parameters of centrifugal atomizing nozzle were obtained, that is, rotary speed of 6000 r/min, flow rate of 48 L/h, VMD of 138.558 μm, and spray swath of 3.42 m.

Abstract:To research the influence of spray operation parameters on droplet size distribution of flat fan nozzle, experiments were conducted by using an open circuit wind tunnel and a Sympatec laser diffraction analyzer. The droplet size of reference nozzle was tested to classify the nozzles’ spray spectra. The droplet size distribution generated by different types of nozzles at different spraying pressure for different wind speed with various distances between the nozzle and the laser beam was analyzed. Experimental results showed that the VMD and percentage of the total volume contained in droplet sizes less than 150μm increased with the increasing of the spray pressure, wind speed and distances between the nozzle and the laser beam. Moreover, the classifications of nozzle’s spray spectrum became lower when the pressure and wind speed rose. The distance between the nozzle and the laser beam and wind tunnel experiment could be used to ensure the accuracy and reliability of measurement results when the laser diffraction analyzer was used to test the droplet size. 

Abstract:A linear 2-DOF model of steering for the four-wheel drive high clearance spray chassis was established. Taking front-wheel turning for example, the actual steering angle was calculated. A steering anti-slip control system by using absolute difference of the actual speed ratio and theoretical speed ratio as control object was designed. The device of steering anti-slip electro-hydraulic system was constructed and by experiment the designed system was verified when the turning angel were at 5°,10°,15°,20°,25°,30° respectively and turning angle changed in continuous between 0°～30°. The results show that the turning anti-slip control effect for four-wheel drive high clearance sprayer is excellent, the maximum control error is 2.01% and the average value is 1.25%.

Abstract:According to modern orchard planting pattern and dynamic center of gravity of orchard sprayer, a mathematical model was established by theoretical calculation and test. The trafficability of large carton orchard sprayer was analyzed. The obstacle height curve with dosage was obtained. In the dosage range of 0~200L, the front wheels crossed obstacles reduced from the 200mm to 84mm. In the dosage range of 200~400L, the front wheels crossed obstacles reduced from the 84mm to 53mm. Rear wheel obstacle height was independent of machine parameters. Experimental were consistent with theoretical calculations. The results showed that the sprayer had outstanding trafficability in orchard.

Abstract:A type of maize root stubble harvester based on a lot of test was designed. It can complete a serial of task including digging, picking, clearing, guiding, collecting and windrowing along side position in sequence. This harvester was consisted of the digging root stubble device, the clearing and picking device, the chain type transporting device, the suspension and hydraulic system, which was used for digging and collecting corn root stubble such as maize and sorghum. In this harvester, the digging shovel with offset handle and the flexible picking device with flex tooth were developed by self-innovation, which could finish picking process under surface for the root stubble of non-coupling maize. The field test results showed that the rate of non-picking root stubble was less than 2.8%, the productivity was 0.955~1.086 hm2/h, the operation broad width was 2.6 m and the reliability coefficient of the whole machine was 96.8%. 

Abstract:A triangle layout of the mechanism of cleaning leaves and breaking tails based on the force analysis of motion of the sugarcane and its material properties was presented. It successfully achieves the functions of raking and cleaning leaves, and breaking tails. The orthogonal experiment on the self developed experiment platform was carried out to verify the effect of the layout and find out the optimal parameter combination. According to the experiment, the optimal combination is: the rotating speed of the raking roller of 700 r/min, the speed of the cleaning roller of 900 r/min, the interaction depth of the raking teeth of 40 mm, and the interaction depth of the cleaning element of 30 mm. The experiment results show that the inverted goods font layout of the mechanism is effective and feasible.

Abstract:Focusing on the problem of requiring a large number of labors for transporting culture bottles during the micropropagation period of tissue culture plantlets, a kind of automatic device for lining up culture bottles was designed. The automatic device transported bottles by using two conveyer belts which had opposite motion directions, and guided, assembled and separated bottles by using guiding board, guiding block and separating block respectively. The main factors which influenced sequencing speed and reliability were guiding belt speed v1, separating belt speed v2, dip angle α of guiding board and wedge angle β of guiding block. The sequencing speed and reliability were satisfactory with v1= 0.25 m/s, v2=0.4 m/s, α=47°and β=35°. Experiment results showed that the device could sequence automatically different size and shape bottles which were used frequently in plant tissue culture production and the sequencing reliability was more than 94%. The sequencing speed was nearly equal and the reliability was different while lining up bottles with same diameter and different shapes, because the bottles with less mass and lower center of gravity were easier to be lined up. Bigger bottles were easier to be sequenced than smaller ones while lining up bottles with same shape and different diameters. 

Abstract:The mass loss characteristic of corncob acid hydrolysis residue (CAHR), corncob and lignin isolated from CAHR (CAHL) were analyzed by using a thermal-gravimetric analyzer (TGA). The evolution of main volatile products pyrolyzed from CAHL was characterized by TGA coupled to Fourier transform infrared spectrometry (TGA-FTIR). Pyrolysis behavior of CAHR and corncob was then investigated on a self-designed pyrolysis apparatus, furthermore, component of pyrolysis gas and char reactivity were also examined. Results of TGA showed that an abrupt mass loss stage for corncob was observed within narrow temperature zone from 250℃ to 450℃, while the CAHR and CAHL decomposed gradually from 180℃ to 800℃. It was indicated by TGA-FTIR that methanol and phenols were released at low temperature of 200～420℃, and that CO and CO2 mainly released after 400℃. The char yield (30.35%～42.64%) from CAHR at 550～850℃ was much higher than that (19.18%～26.40%) from corncob, and CO2 gasification reactivity of CAHR char was lower than that of corncob char. The yield of CO, CO2 was higher compared with that of H2 and CH4, and H2 yield was notably enhanced at pyrolysis temperature over 650℃.

Abstract:The thermochemical characteristicsand kinetics of chicken dung were studied on thermogravimetric apparatus at different heating rates. It was showed that five steps were included in the pyrolysis process of chicken dung: losing water, pre-pyrolysis, main pyrolysis, second pyrolysis and carbonization. As heating rate increased, the most weight loss rate increased greatly, and the characteristic temperature became higher. With Malek method，reaction model could be determined, which indicated that pyrolysis mechanism of chicken dung was random nucleation and later growth. As the activation energy and frequency factor were estimated by bringing into pyrolysis reaction, the results were similar with the consequence calculated by Ozawa method, which showed that activation energy E was 180.83 kJ/mol, frequency factor lgA was 14.27 s-1 and activation series n was 1/3. By conventional pyrolysis experiment and analyzing the solids product ratio at the certain temperature, the result was in accordance with the residual carbon from TG test, which proved that result from TG test was reliable. 

Abstract:The agglomeration phenomenon of tobacco stems was investigated on a pilot-scale fluidized bed at temperature between 800℃ and 900℃ with two kinds of bed materials silica sand and cinder, followed by a discussion on the agglomeration mechanism. The results indicated that the inclination of agglomeration for the two bed materials above was different. Severe incineration was found in silica sand which led to defluidization finally, while no agglomeration was discovered during long-term run. The data from X-ray fluorescence and scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) indicated that Al, Fe contained in cinder could react with alkali metals in the tobacco stem ash to form high-melting compounds, which prevented the agglomerates to grow, therefore inhibit the agglomeration.

Abstract:Simulation models regarding moisture content were developed respectively by law of conversation of mass and first order assumption with respect to the quality of moisture content. Approaches by law of conversation of mass to moisture content prediction was based on an analysis of biologically produced water, exit gas content and inlet air content, with the biological water estimated from yield factors based on biodegradable volatile solid degradation. The other approach to moisture content prediction based on first order moisture evaporation kinetics was developed by an analysis of composting pile moisture content and aeration rate. An aerobic composting process of pig slurry and wheat straw was conducted in order to verify the models constructed. The experimental results showed that modeling results gave good accuracy, and the relative standard error of law of conservation of mass model and first order assumption model were respectively 8.01% and 8.86%.

Abstract:The microwave-vacuum drying characteristics of litchi pulp were studied and the effects of microwave power, relative pressure and loading capacity on drying rate of litchi pulp were investigated. The results showed that the drying rates of litchi pulp were markedly affected by microwave power and loading capacity, whereas, there was no obviously affected by relative pressure. The experimental drying data of litchi pulp were used to fit twelve available drying models, and coefficients of models were determined by non-linear regression analysis. It showed that Modified Henderson and Pabis model had higher correction coefficient R2, lower square sum of error (SSE) value and root mean square error (RMSE) value and could exactly describe and predict the moisture dynamics of litchi pulp during microwave-vacuum drying process.

Abstract:In order to ensure the consistency in the direction of fresh eggs under package, a device for automatic orientation of the blunt and tip sides of eggs, which is composed of the roller delivery system, veering system and regulator drive system was developed. Based on the principles of mechanical transmission, the design methods for the axial motion and the oriented roll were established, also the construction parameters of the device were determined. The experimental results showed that the axial motion of eggs was stable. The roll over the length was fluent and the attitude was reliable, besides. The accuracy of the orientation was 100%. The egg-orientation speed of the device in single channel was 0.87～1.22 eggs per second. The nominal egg-orientation speed (in two channels) was 7200 eggs per hour.

Abstract:In order to improve the accuracy of apple grading in digital image processing system, the multi-feature information was extracted for describing the apple features. However, this method may result in information redundancy and so on. So, the principal component analysis (PCA) was used to carry out information fusion of the feature parameters, and with the aid of Wilks Λ statistic the principal components (PC) which could promote grading results were selected. Then some features used in grading were selected based on the contribution rate to selected PC. The results of Fisher discriminate analysis (FDA) showed that the grading effect corresponding to the selected features was better than that of all features, and the grading accuracy and the cross-validation accuracy rose by 2.0% and 1.5%, respectively.

Abstract:The effects of the different operation conditions such as the voltage supplied to the electrodes, the flux of the hydrochloric acid solution, the pH value of the raw water and hydrochloric acid solution concentration on the available chlorine content, the pH value and the electrical conductivity of the slightly acidic electrolyzed functional water (SAEFW) were investigated with a continuous electrolyzed functional water generating system which was independently developed. The results showed that the available chlorine concentration of the SAEFW increased significantly with the increase in the voltage in the range of 3~5 V (P<0.01), but the influences of the voltage on the pH value and the electrical conductivity of the SAEFW were not noticeable (P>0.05). It was also found that the available chlorine and the electrical conductivity of the SAEFW also increased significantly with the increase in the flux of the hydrochloric acid, solution, but the pH value of the SAEFW decreased obviously when the flux of the hydrochloric acid solution increased (P<0.01). In addition, as the pH value of the raw water rose, the pH value and the electrical conductivity of the SAEFW increased and decreased significantly, respectively (P<0.01). However, the effect of the pH value of the raw water on the available chlorine of the SAEFW was not significantly different (P>0.05). At last, the available chlorine concentration and electrical conductivity of the SAEFW increased with the increase of the hydrochloric acid solution concentration, on the contrary, the pH value decreased (P<0.01). 

Abstract:The biomass of Monascus purpurcus solid-state fermentation influenced by low frequency alternating magnetic field (50 Hz, 0~2 mT) was main studied in order to discuss the magnetic field influence on the performance of engineering bacteria fermentation. Results showed that the magnetic treatment could promote Monascus purpurcus biomass producing in the third day with the maximum improving of 29.9% at 0.6 mT. The biomasses of treatment group and control group reach maximum in the eleventh day with the whole procedure of 15 days and magnetic field intensity of 0~2 mT. But the biomass and substrate consumption ratio of treatment group and control group did not show obviously difference. Low-frequency alternating magnetic field could promote Monascus purpurcus growth, then change their metabolic way and enhance the fermentation benefits. 

Abstract:The aromatic compounds in perry were evaluated by combining SPME with GC-MS and GC-O methods on the basis of fermentation in Jingbai pear.Before fermentation, the sugar degree of Jingbai pear juice was adjusted by pear juice concentrate, granulated sugar and autumn pear grease separately. It was confirmed that pear wine adjusted to 16°Brix by granulated sugar, gained the best sensory quality and more affluent volatile components, comparing to the raw juice and pomace. The Jingbai pear wine pilot scale fermentation was carried on based on the laboratory parameters. The key aroma components included 1-butanol, 3-methyl-, acetate; hexanoic acid, ethyl ester; acetic acid, hexyl ester; octanoic acid, methyl ester; butanedioic acid, diethyl ester; octanoic acid, ethyl ester; acetic acid, 2-phenylethyl ester; ethyl 9- decenoate; decanoic acid, ethyl ester; 1-butanol, 3-methyl-; 1-hexanol; phenylethyl alcohol; 3-buten-2-one,4- (2,6,6- trimethyl-2- cyclohexen-1-yl). These aroma components were compared in different pear wines. The results illustrated a new way for the quality Jingbai pear wine improvement through the fermentation by different perspectives on the analysis of aroma components.

Abstract:The yield of soluble whole-cell protein from Alicylobacillus acidoterrestris DSM 3922T cells is dependent on the effectiveness of cell lysis post fermentation. Various cell lysis approaches were investigated, including ultrasound, SDS, boiling, lysozyme, and cell lysis reagent treatment, and the different samples of soluble protein were determined by SDS protein polyacrylamide gel electrophoresis. The soluble whole-cell protein by one-factor-at-a-time experiments and response surface method was optimized. The results showed that the cell lysis reagent treatment was the most effective in extracting soluble whole-cell protein. The most significant processing parameters, namely incubation temperature, reaction time, and the ratio of cell lysis reagent volume and bacteria weight (A/B ratio), were optimized by using the Box-Behnken with a quadratic regression model built by response surface methodology (RSM). The influence order of factors to protein extraction rate was: A/B ratio, time and temperature. The highest soluble whole-cell protein yield at 161.18 mg/g was attained under optimal time, temperature, and A/B ratio at 37.4 min, 18.9℃, and 27.0 mL/g, respectively. The regression model of soluble whole-cell protein extraction was highly significant (R2=0.989 2), the experimental and simulated results were found to be in good agreement, which could be used to forecast.

Abstract:A kind of optimal path planning method for complete field coverage in agricultural machinery farming was described. The given convex field was decomposed into sub regions according to typical faming pattern of complete field coverage. Optimal path planning should minimize agricultural machines turns, farming time, route distance or other optimization object. According to the different purpose of path planning above, optimal travel direction could be determined based on topological features of arable lands, turns pattern in the headland and other useful information. Farming path planning software was developed by using this algorithm. The test results from four actual quadrangular fields showed that the optimization object for field operation in optimal travel direction decreased obviously compared with other directions. Each optimal travel direction in those quadrangular fields above was along any edge. Especially for a quadrangle having a larger edge ratio, the optimal travel direction was almost the longest edge. 

Abstract:A prototype for intelligent fruit picking operation was developed. It mainly consisted of intelligent mobile platform, picking arm, end-effector, transverse sliding institution and control systems. The system control program and human-machine interface were programmed with VC++. The comprehensive experiments of the prototype were carried out in the orchard of Feng county in Jiangsu province. Results revealed that this robot could achieve autonomous navigation, independent picking and autonomous binning operation. The mobile platform, picking arm and end-effector can work coordinately, so the whole system performed very well. The correct rate of ripe fruit recognition and success rate of picking reached to 81.73% and 86.92%, respectively, whereas averagely 9.50 s were required for picking a single apple.

Abstract:The problem of detect navigation line by machine vision under non structural environment and complex background in greenhouse was addressed. After analyzing the distribution characteristics of the road images in tomato ridges based on HSI color space, a method was proposed for extracting the sensitive region of the heat pipe. Firstly, the binary images were generated from the road images by using Otsu segmentation method based on I histogram. The discrete set of navigation points was obtained by using edge extraction algorithm in accordance with the binary images. And then, the two sidelines of the heat pipe were obtained by using the least square method to fit the discrete points, on the basis of this, the navigation line detection algorithm was proposed. Finally, the influences of the illumination in homogeneity and the different covering on navigation line detection were investigated. The experimental results indicated that in comparison with Hough transform, the algorithm was simple and fast, as well as robust with illumination in homogeneity, the edge information of target region could be extracted accurately and the recognition correct rate under different covering was 91.67%. 

Abstract:To solve the problem of segmentation for overlapping fruits, an image segmentation algorithm based on disparity map was developed. Firstly, binocular stereo images were obtained by binocular stereo vision system. Then, these images were preprocessed and rectified. Thirdly, stereo matching for rectified images pair to get disparity values for every pixel was made. At last, the disparity map was generated. Distance information in 3-D space was added to algorithm besides color, shape and texture information in 2-D space, so the fruits with different distances in actual space were segmented better in disparity map than in normal image. Experimental results showed that the accuracy of segmentation for disparity map by area-based method was 0.90, and the edge detection error was 5.74%. The proposed method was valid for segmentation of overlapping fruits. 

Abstract:A method of measuring moisture content for plant material powder based on HM1520LF capacitive humidity sensor was introduced. The raw data sequence of moisture content was acquired by measurement system which consists of capacitive humidity sensor and data acquisition card. After excluding alternative singular by one rank difference method, inertia filtering method was employed to process the data sequence. By accordingly comparing 13 measured values of moisture content with corresponding true values from the baking oven, the maximal relative error of moisture content between measured values and true values was 1.61%, and the average relative error was 0.76%, both less than 5% (confidence interval 95% for 5 samples). As a result, the method can be used to determine the low moisture content of plant material powder. 

Abstract:In order to monitor the aquatic environment and fish state in offshore aquaculture cage farm daily, a centralized remote monitoring system for bred fish was developed. The system was composed of remote detecting node (RDN) and local monitor and control center (LMCC). RDN based on the techniques of multi-beam detection and multi-path signal process was placed in the center of a cage to scan the inner cage and measure the aquatic environment. LMCC based on LabVIEW was placed in the office to manage all the remote detecting nodes remotely and show fish state. The communication between LMCC and RDN depended on GPRS wireless data transmission technology. The system prototype was tested in the field of offshore aquaculture cage farm in Quanzhou, Fujian province. The results show that the system is reasonable design, simple operation, easy placement, and robust under different environmental conditions. It can real-time monitor the aquatic environment and fish activity remotely, provide users with a variety of information such as fish amount, fish growth in the offshore fish cage, and give an alarm in the time when net clothing damage or fish escape.

Abstract:The thermal resistant characteristics of pests in agricultural products are important to determine the lethal temperature and time for thermal disinfestation methods. Therefore, a set of research system was designed and built to obtain the given heating rate and temperature required by thermal controls of pests. The temperature detection and control circuits were mainly developed by using AVR Atmega16 single chip microcomputer (SCM) as controller, Pt100 as temperature sensor, and pulse width modulation as temperature control method. The C language and VB software were used to control SCM procedure and personal computer monitoring/data acquisition, respectively. The running results showed that the temperature measurement and control accuracy was 0.2℃ and 0.1℃ for heating up to 10~70℃. The heating rate could be achieved over the range of 0~15℃/min.

Abstract:Reconfigurable manufacturing process design was combined with characteristics of reconfigurable machine tools. Beginning with the proposed process unit and process section, the processing information matrix was built through the processing information formulation. Then the processing unit was established and the division method of process section was proposed. Through the cross two way method, a variety of process schemes which meet the reconfigurable manufacturing requirements were obtained. Based on the similarity judgment model of processing plan, the reasonable processing schemes for the reconfiguration of reconfigurable machine tools were found out, which provided scientific basis for realizing the manufacturing flexibility in part family. Finally, an example of processing design for the cylinder front covers family was given to verify the validity of the proposed processing method.

Abstract:A conceptual framework for product ecosystem was proposed. System dynamic method was used to analyze the effect of system elements in product survival and evolution. First, similarities between the product environment system and natural ecosystem were analyzed. Then, a model for product ecosystem was constructed, and the key relationships between the product and its environment was analyzed by using system dynamic method for describing the effect of environment in product evolution. Lastly, a phylogenetic analysis of self-priming pump was given as an example.

Abstract:Based on the Hertz contact theory of elastic mechanics, a static stiffness model of double ball screws joint was built by analyzing the linear stiffness of double linear guide rails and the axial stiffness of double ball screw and ball bearing. The permanent magnet linear synchronous motor’s normal force affected the deformation of the feeding system. Based on the static stiffness model, deformation of the tool point was analyzed by finite element method and compared with the experimental results. The simulation results were in good agreement with measured data and indicated the accuracy of the static stiffness model. 

Abstract:The proximate analytic results of fractal dimension and fractal roughness were derived. Some solutions associated with normal contact stiffness in joint interface were modified. A general Matlab program was compiled to solve the domain extension factor. The analytic expression for the tangential contact stiffness was deduced about joint interface. A joint interface selected as an example in XHK5140 automatic tool-changing CNC vertical boring and milling machine tool in terms of the experimental results about test specimen, the theoretical expressions for normal and tangential contact stiffness were validated via the correlation of similar vibration shape and quantitative comparison tenet of natural frequencies. The theoretical vibration shapes were in good line with the experimental ones. The relative error between the theoretical natural frequencies and the experimental results distributed from -16.8% to 16.8%. 

Abstract:Considered structure vibration of angular contact ball bearing, the elastic deformation of rolling elements in form of matrix or vector was defined so as to keep structural integrity and get clear notation, in this way, the elastic deformation of every rolling element could be calculated easily. Combining Hertz contact theory and Lagrange mechanics theory, a 5-DOF dynamic model was built. By using this model, the relationship between the frequency of structure and the preload, the contact angle and ball position was discussed. Eexperimental results proved that the error of the dynamic equation was less than 15%, which met the requirement of engineering calculations.

Abstract:Numerical analysis was carried out for elastohydrodynamic lubrication (EHL) of tapered roller considering moment balance. The equation of moment balance, corresponding to the discrete method and the formula of relative error were given. Position angle of roller changed with the relative error in order to satisfy the moment balance. When considering the moment balance, effects of load, velocity and half-tapered angle on the position angle of roller, pressure and film thickness were analyzed. Results showed that, if load is in the geometrical center of a roller, moment balance could be ignored for the EHL of cylindrical roller. However, it is very important for that of tapered roller. In order to satisfy the moment balance, the position angle of roller would be increased, and large end would be raised. The tiny variation of the position angle would cause severe changes of EHL of tapered roller. The numerical analyses considering moment balance are closer to the real working condition. Meanwhile, the effects are more obvious with the increasing of load, velocity and half-tapered angle.

Abstract:To construct the spatial cam parametric feature model efficiently and accurately, discrete point cloud data were obtained by profile equation of spatial cam. Non-uniform rational B-splines (NURBS) was adopted to reconstruct the profile of spatial cam. Based on the parametric feature model, the spatial cam indexing mechanism was set up to perform kinematics simulation, and then the manufacturing model was generated to simulate the spatial cam NC machining. Finally, the spatial cam was machined on four-axis CNC machining center by NURBS interpolation method. The results showed the follower motion curves (the maximum velocity and acceleration) were smoother than modified-sine curves. The profile machining error related to the processing route curvature, the maximum was not more than 0.01mm and located in the maximum of the absolute curvature. Profile reconstruction based on NURBS was liable and effective for design and machining of spatial cam. 

Abstract:The multi-roll stretch forming process of saddle-shaped surface parts with flexible floating clamping mode were simulated by ANSYS/LS-DYNA. The effect of flexible floating clamping mode was verified. The distribution of stress and strain of formed parts was analyzed. Results indicated that the flexible floating clamping mode was suitable for the process of the multi roll stretch forming process. The stress and strain of the formed part distributed uniformly. Finally, the corresponding experiment was accomplished. When comparing the results of the numerical simulation and that of the experiment, it was concluded that the two types of results were nearly consistent.