Based on an analysis of the relative shaft-to-hole position and attiude errors, as well as of the mechanics and Kinematics in the process of automatic assembly of industrial robots, the paper studies the principle of ...Based on an analysis of the relative shaft-to-hole position and attiude errors, as well as of the mechanics and Kinematics in the process of automatic assembly of industrial robots, the paper studies the principle of construction of dynamic wrists. Type I-3 and Ⅱ-6 dynamic compliant wrists have been designed and made. Prblems in the production of compliant elements and the connection between compliant elements and wrists were also solved. A study on the results of tests of the function of two kinds of dynamic compliant wrists shows that the dynamic compliant wrist's compliancy function can be improved by adding metallic materials having higher longitudinal and transverse rigidity into the softer elstomer. And the design Principle is proved to be feasible and practicable. It can be expected that the use of dynamic compliant wrist will greatly lower the technical requirements of the shaft-hole assembly and the requirements in the resetting accuracy.展开更多
Monte Carlo simulation was applied to Assembly Success Bate (ASK) analyses. ASR of two peg-in-hole robot assemblies was used as an example by taking component parts' sizes, manufacturing tolerances and robot repea...Monte Carlo simulation was applied to Assembly Success Bate (ASK) analyses. ASR of two peg-in-hole robot assemblies was used as an example by taking component parts' sizes, manufacturing tolerances and robot repeatability into account. A statistic arithmetic expression was proposed and deduced in this paper, which offers an alternative method of estimating the accuracy of ASR, without having to repeat the simulations. This statistic method also helps to choose a suitable sample size, if error reduction is desired. Monte Carlo simulation results demonstrated the feasibility of the method.展开更多
Aiming at the assembly accuracy of a large aircraft transport jig, the effect of component error and the error of work-piece surface on the work-piece position and orientation in the 3-2-1 fixturing scheme is studied ...Aiming at the assembly accuracy of a large aircraft transport jig, the effect of component error and the error of work-piece surface on the work-piece position and orientation in the 3-2-1 fixturing scheme is studied with the object pose space description method. The error mapping model between the connecting part of the front frame rack and its support base is modeled using the homogeneous transformation matrix(HTM) method. The probabilistic error is simulated using the Monte Carlo method. The measurement experiment was conducted by the laser tracker to verify the effectiveness of the approach, and the approach has been successfully applied to the production of transport jig.展开更多
As a result of 30 years of an internal armed conflict, women and children not only lost male relatives in struggle, but comprised of the displaced. Most of the households in Sri Lanka are now headed exclusively by wom...As a result of 30 years of an internal armed conflict, women and children not only lost male relatives in struggle, but comprised of the displaced. Most of the households in Sri Lanka are now headed exclusively by women. The micro finance institutions help the poor people in effective ways in order to generate income to enhance their standard of living in the rural areas. This study focuses on women entrepreneurship development through micro credit programme under post war development in Jaffna District selecting four rural areas which are Kopay, Chavakachcheri, Varani and Kodikamam. The main objective of this study is to identify the linkage with micro credit programmes and entrepreneurship development. Further it has an objective to identify the impact of micro credit on entrepreneurship development. The information has been gathered by primary data which has been distributed through the close ended questionnaire to the rural women in the above selected areas and seventy seven （77） responded out of 100. The relation between the micro credit programmes and women entrepreneurship development is examined using Statistical Package for Social Sciences （SPSS）. It is concluded that the Entrepreneurship development has a significant relationship （p〈0.05） with the microcredit programme and its impact on entrepreneurship development is crucial. It is suggested that the microcredit facilities are essential in women entrepreneurship development under post war development.展开更多
Agricultural mechanization is to the use advanced and applicable agricultural machinery and equipment in agriculture to improve agricultural production conditions, and continuously improve the production technology an...Agricultural mechanization is to the use advanced and applicable agricultural machinery and equipment in agriculture to improve agricultural production conditions, and continuously improve the production technology and economic, ecological processes of agriculture. The level of agricultural science and technology depends largely on the degree of agricultural mechanization promotion. An agricultural country level depends on the degree of modern agricultural mechanization level of the application, and the era of mechanization in agriculture can not only save a lot of labor, reduce labor intensity, but also improve labor efficiency, and enhance resistance to natural disasters. The importance of agricultural mechanization technology in the scientific and technological achievements in agriculture is visible.展开更多
文摘Based on an analysis of the relative shaft-to-hole position and attiude errors, as well as of the mechanics and Kinematics in the process of automatic assembly of industrial robots, the paper studies the principle of construction of dynamic wrists. Type I-3 and Ⅱ-6 dynamic compliant wrists have been designed and made. Prblems in the production of compliant elements and the connection between compliant elements and wrists were also solved. A study on the results of tests of the function of two kinds of dynamic compliant wrists shows that the dynamic compliant wrist's compliancy function can be improved by adding metallic materials having higher longitudinal and transverse rigidity into the softer elstomer. And the design Principle is proved to be feasible and practicable. It can be expected that the use of dynamic compliant wrist will greatly lower the technical requirements of the shaft-hole assembly and the requirements in the resetting accuracy.
文摘Monte Carlo simulation was applied to Assembly Success Bate (ASK) analyses. ASR of two peg-in-hole robot assemblies was used as an example by taking component parts' sizes, manufacturing tolerances and robot repeatability into account. A statistic arithmetic expression was proposed and deduced in this paper, which offers an alternative method of estimating the accuracy of ASR, without having to repeat the simulations. This statistic method also helps to choose a suitable sample size, if error reduction is desired. Monte Carlo simulation results demonstrated the feasibility of the method.
基金Supported by National Key Technology Research and Development Program of China(No.2012BAF01B07)
文摘Aiming at the assembly accuracy of a large aircraft transport jig, the effect of component error and the error of work-piece surface on the work-piece position and orientation in the 3-2-1 fixturing scheme is studied with the object pose space description method. The error mapping model between the connecting part of the front frame rack and its support base is modeled using the homogeneous transformation matrix(HTM) method. The probabilistic error is simulated using the Monte Carlo method. The measurement experiment was conducted by the laser tracker to verify the effectiveness of the approach, and the approach has been successfully applied to the production of transport jig.
文摘As a result of 30 years of an internal armed conflict, women and children not only lost male relatives in struggle, but comprised of the displaced. Most of the households in Sri Lanka are now headed exclusively by women. The micro finance institutions help the poor people in effective ways in order to generate income to enhance their standard of living in the rural areas. This study focuses on women entrepreneurship development through micro credit programme under post war development in Jaffna District selecting four rural areas which are Kopay, Chavakachcheri, Varani and Kodikamam. The main objective of this study is to identify the linkage with micro credit programmes and entrepreneurship development. Further it has an objective to identify the impact of micro credit on entrepreneurship development. The information has been gathered by primary data which has been distributed through the close ended questionnaire to the rural women in the above selected areas and seventy seven （77） responded out of 100. The relation between the micro credit programmes and women entrepreneurship development is examined using Statistical Package for Social Sciences （SPSS）. It is concluded that the Entrepreneurship development has a significant relationship （p〈0.05） with the microcredit programme and its impact on entrepreneurship development is crucial. It is suggested that the microcredit facilities are essential in women entrepreneurship development under post war development.
文摘Agricultural mechanization is to the use advanced and applicable agricultural machinery and equipment in agriculture to improve agricultural production conditions, and continuously improve the production technology and economic, ecological processes of agriculture. The level of agricultural science and technology depends largely on the degree of agricultural mechanization promotion. An agricultural country level depends on the degree of modern agricultural mechanization level of the application, and the era of mechanization in agriculture can not only save a lot of labor, reduce labor intensity, but also improve labor efficiency, and enhance resistance to natural disasters. The importance of agricultural mechanization technology in the scientific and technological achievements in agriculture is visible.
