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COMPUTER VISION APPLIEDIN THE precision CONTROL SYSTEM

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Chinese Journal of Mechanical Engineering 2002年第1期15卷 87-89页

作者： Zhang Qingying Logistics Engineering Department，Wuhan University of Technology，Wuhan 430063，China Logistics Engineering Departiment Wuhan University of Technology Wuhan 430063

Computer vision and its application in the precision control system arediscussed. In the process of fabricating, the accuracy of the products should be controlledreasonably and completely. The precision should be kept and adjusted according to the information offeedback got from the measurement on-line or out-line in different procedures. Computer vision isone of the useful methods to do this. Computer vision and the image manipulation are presented, andbased on this, a n-dimensional vector to appraise on precision of machining is given.

关键词： Computer vision Measurement precision Quality of products

Parameter optimization and experiment of the negative pressure precision seed-metering device for wheat

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 154-162页

作者： Yubo Feng Xiaoshun Zhao Jincai Li Huali Yu Hongpeng Zhao Baozhong Yin State Key Laboratory of North China Crop Improvement and Regulation Hebei Agricultural UniversityBaoding 071001HebeiChina College of Mechanical and Electrical Engineering Hebei Agricultural UniversityBaoding 071001HebeiChina College of Plant Protection Hebei Agricultural UniversityBaoding 071001HebeiChina

In order to ensure the most reasonable distribution of wheat seeds in the field to improve seeding quality and uniformity,a set of negative pressure precision seed-metering device was designed,which shares a hollow *** seed-metering device can sow two rows of *** the STAR-CCM+,the analysis of nephogram,vectogram and streamline graph showed that more ideal structural parameters of the seed-metering device are 0.5 mm width of the slit sucking seed(WSS),150-200 mm diameter of the seed-metering disc(DSD),2.0 mm axial depth of air chamber in the seed-metering disc(ADS),and arc-shaped cross-section shape of the ring groove sucking seed(CSGS).Single-factor test on the JPS-12 test-bed analyzed the influence of the CSGS,WSS,DSD,and ADS on the qualified index(Iq),multiple index(Imul),miss index(Imiss)and coefficient of variation of qualified seed spacing(CV).Through the orthogonal on the JPS-12 test-bed,it is found that the influence of vacuum negative pressure and seed-metering device shaft speed is significant on the Iq,Imiss and *** on these,the structural parameters of the seed-metering device were *** DSD is 180 mm,the WSS is 0.7 mm,the ADS is 2.5 mm,and the CSGS is *** optimization seed-metering device was tested on the JPS-12 *** Iq is 86.66%,the Imiss is 5.09%,the Imul is 8.25%,and the CV is 24.50%.These testing results fully coincide with the standard JB/T 10293-2013 Specifications of single seed drill(precision drill).The seed-metering device meets fully the requirements for wheat precision seeding.

关键词： wheat seed-metering device negative pressure precision parameter optimization STAR-CCM+ orthogonal test variance analysis

Design and experiment of the pneumatic cylinder type precision metering system for wheat

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International Journal of Agricultural and Biological Engineering 2023年第5期16卷 88-94页

作者： Anas Dafaallah Abdallah Qingxi Liao Elebaid Jabir Ibrahim Lei Wang College of Engineering Huazhong Agricultural UniversityWuhan 430070China Department of Agricultural Engineering Faculty of Agricultural ScienceUniversity of GeziraWad MedaniP.O.Box 20Republic of Sudan

The main goal of this study was to design a pneumatic cylindrical-type metering device with six-rows for wheat precision and to analyze its output under different rotating speeds and vacuum pressure *** effect of the pressure,rotating speed and rows on seed suction,retention and dropping was shown *** levels of rotating speed(5,10,15,20,25 and 30 r/min.)combined with the applying of different vacuum pressures(1.8,2.1,2.4,2.7,3.0,and 3.3 kPa)were inspected to detect the optimum pressure which was adequate for seed sucking at each *** addition,to predict the vacuum pressure corresponding with each rotating speed,a regression model was *** on seed mass analysis,statistical differences under the influence of velocities and negative pressure were found at 5 percent significance according to Duncan’s Test,whereas the differences were existed between and within *** revealed that the highest seed mass means of 19.02 g and 22.64 g were obtained by row1while the lowest means of 18.02 g and 21.49 g were attained by row6 under the effect of the speed and vacuum pressure,*** noticeable variation between row1 and row 6,particularly under high speeds(25 and 30 r/min),might be returned to the truth that row 1 was closer to vacuum inlet,and row 6 was the farthest *** concluded that the multiple-row pneumatic cylinder with oblong shape seed nozzle was found to be capable for single seed picking with a small rows variation but without seed damage.

关键词： Multi-rows cylinder pneumatic metering device wheat precision

Design and experiment of the double-seed hole seeding precision seed metering device for peanuts

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International Journal of Agricultural and Biological Engineering 2022年第3期15卷 107-114页

作者： Xiaoshun Zhao Wenjing Ran Jianjun Hao Wenjie Bai Xinlei Yang College of Mechanical and Electrical Engineering Hebei Agricultural UniversityBaoding 071001HebeiChina

A secondary seeding precision double-seed peanut hole seeding seed metering device was designed to improve the performance of the peanut planting equipment and provide a solution for problems on the high seed charge that can cause poor cavitation and uniformity *** main structure and operation parameters in terms of groove length,seed charge height,seed-bed belt speed,and rotation speed of the seed metering wheel were determined through theoretical ***-factor and orthogonal tests were carried out through the JPS-12 seed metering device test bench,and the peanut variety Jinonghua-3 was selected as the test *** single hole double-seed rate,qualified rate,the variation coefficient of hole spacing,and hole rate were chosen for evaluating the working *** results of the single-factor test showed that the seed metering performance is mainly affected by the groove length,the speed of the seed-bed belt and the rotation speed of the seed metering wheel,and the influence of the cavitation rate is *** optimal seeding height is determined to be 40 *** results of the orthogonal test showed that the groove length was 27.3 mm,the seed-bed belt speed was 1.51 km/h,and the rotation speed of the seed metering wheel was 14.11 r/***’s more,a regression model based on the orthogonal test results was established,the qualified rate of the number of holes obtained after optimizing the model was 98.84%,the variation coefficient of hole spacing was 9.74%,and the hole rate was 1.40%.Notably,the working performances of the device can meet the requirement of precision seeding.

关键词： peanut precision seed metering device orthogonal test regression method

MEASURING precision OF INDUCED POLARIZATION METHOD

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中国有色金属学会会刊：英文版 1994年第4期4卷 1-6页

作者： He,Jishan(Central South University of Technology,Changsha 410083)

ＭＥＡＳＵＲＩＮＧＰＲＥＣＩＳＩＯＮＯＦＩＮＤＵＣＥＤＰＯＬＡＲＩＺＡＴＩＯＮＭＥＴＨＯＤ￥Ｈｅ，Ｊｉｓｈａｎ（ＣｅｎｔｒａｌＳｏｕｔｈＵｎｉｖｅｒｓｉｔｙｏｆＴｅｃｈｎｏｌｏｇｙ，Ｃｈａｎｇｓｈａ４１００８３）Ａｂ... 详细信息

ＭＥＡＳＵＲＩＮＧＰＲＥＣＩＳＩＯＮＯＦＩＮＤＵＣＥＤＰＯＬＡＲＩＺＡＴＩＯＮＭＥＴＨＯＤ￥Ｈｅ，Ｊｉｓｈａｎ（ＣｅｎｔｒａｌＳｏｕｔｈＵｎｉｖｅｒｓｉｔｙｏｆＴｅｃｈｎｏｌｏｇｙ，Ｃｈａｎｇｓｈａ４１００８３）Ａｂｓｔｒａｃｔ：Ｏｎｔｈｅｐｒｅｍｉ...

关键词： measuring precision induced polarization method (IP) dual-frequency IP frequency domain IP time IP

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Development of embedded automatic transplanting system in seedling transplanters for precision agriculture

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Artificial Intelligence in Agriculture 2021年第1期5卷 175-184页

作者： Abhijit Khadatkar S.M.Mathur K.Dubey V.BhusanaBabua ICAR Central Institute of Agricultural EngineeringBhopal 462038India College of Technology and Engineering MPUATUdaipur 313001India

Hand transplanting of vegetable seedlings is always been a time consuming and labourious activity which often leads to muscular *** of hitech instrumentation increased to achieve precision and automation in agricultural *** present the transplanting is done manually which accounts for large amount of hand labour and *** ensure precision and timeliness in operation,an automatic transplanting based on embedded systemfor use in seedling transplanters was *** developed systemconsists of feed roller,pro-tray belt,a pair of L-shaped rotating fingers,embedded system,DC and stepper *** plug seedlings were released into the furrow with use of developed embedded system by actuating DC as well as stepper *** performances of the developed system was tested rigorously at four different operating speeds(1.0,1.5,2.0 and 2.5 km/h)and three angles of pro-tray feed roller(00,300,450)for attaining optimum plant to plant spacing in soil *** result indicated that percent transplanting and plant to plant spacing was found optimum at 2.0 km/h forward speed and 300 angle of pro-tray feed *** average plant spacing,transplanting efficiency,furrow closer,angle of inclination and miss planting were 600 mm,91.7%,90.3%,18.30 and 2.1%,*** developed system ensures the precision by sigulating the placement of seedlings at optimumspacing for sustainable agriculture *** also enabled the optimumtransplanting rate,the ability to transplant at higher speeds and maintaining proper plant to plant spacing.

关键词： Automation precision Seedlings Transplanting Embedded system Sustainable

Influence of velocity on the transmission precision of the ball screw mechanism

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High Technology Letters 2020年第2期26卷 217-223页

作者： Kong Deshun Institute of Standard Metrology China Academy of Railway Sciences Corporation LimtedBeijing 100081P.R.China Beijing Huaheng Technology Co.Ltd. Beijing 100081P.R.China

Ball screw mechanism(BSM)is an important force-motion transfer device which is used in high-precision machine tools such as the computer numerical *** parameters such as contact angle,helix angle,and the pitch radius of the screw can greatly affect the transmission precision,and the transmission precision of the BSM are not yet well *** this study,ball contact point motion model is derived to assess the influence of contact angle,helix angle,and the pitch radius of the screw on transmission precision under uniform motion of the *** the purpose of verifying the kinematic characteristics of the contact points between the balls and raceways under a state of uniform motion,a kinematic model is developed and values are computed for a set of boundary *** the simulated data to measured data,the laws of motion for the ball contact points developed in this study are ***,the effect of the screw velocity on contact angle,helix angle and the pitch radius of the screw directly affects the velocity of the *** the accelerated and uniform motion state of the screw,larger angular velocity of the screw results in an increase in the displacement deviation of the nut,and these parameters of the nut are considered to improve the transmission precision of the *** verification of the research results provides a new research method for the study of the precision retention of ball screw mechanism.

关键词： ball screw mechanism(BSM) uniform motion structural parameters transmission precision

Error compensation for precision machine tools

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Journal of Harbin Institute of Technology(New Series) 2002年第3期9卷 282-287页

作者： LU Zesheng(卢泽生) ZHENG Dezhi(郑德志) DU Jinming(杜金名) Dept. of Mechanical Engineering Harbin Institute of Technology Harbin 150001 China Dept. of Mechanical Engineering Harbin Institute of Technology Harbin 150001 China Dept. of Mechanical Engineering Harbin Institute of Technology Harbin 150001 China

As one of the ways to improve the machining accuracy of machine tools, error compensation is reviewed from different view points, and the main barriers to further improvement of efficiency of error compensation are an... 详细信息

关键词： error compensation machining accuracy precision machine tool

Study on the method of precision adjustment of star sensor

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Nanotechnology and precision Engineering 2018年第4期1卷 248-257页

作者： Xiaoyan Wang Ran Zheng Yanpeng Wu Jianbo Sun Jun Zhong Long Wang Miaomiao Wang Beijing Institute of Control Engineering Beijing 100190China

Star sensors are indispensable spatial measurement sensors for high-resolution earth observation and astronomical observations, and the demand for high measurement accuracy of satellite sensors continues to increase; thus, the star sensor optical machine adjustment error cannot be ignored. The commonly used installation error correction method cannot solely meet the precision analysis requirements. In this paper, the relationship between the optical machine installation and the star sensor measurement error is analyzed, and several common adjustment error correction methods are compared. An adjustment method for optical machines is proposed to meet the requirements of very high precision star sensors. The assembly precision requirements of the investigated very high precision star sensor are analyzed considering the whole machine, and then the optical components are controlled through optical precision adjustments to satisfy the precision requirements. Finally, through the complete machine calibration, the star sensor precision adjustment for an optical machine structure is verified. This method meets the requirements of very high precision sensors and is suitable for the precision adjustment of optical machine structures, which is of practical significance to improve the precision of star sensors.

关键词： Very high precision star sensor Optical machine structure Alignment precision precision adjustment