The applications of bionic methodology developed by the Laboratory of Design and Material Selection as basis in the creation of junction elements were demonstrated. These elements favor the application of Ecodesign in...The applications of bionic methodology developed by the Laboratory of Design and Material Selection as basis in the creation of junction elements were demonstrated. These elements favor the application of Ecodesign in reference to the effectiveness of product dismount aiming the reduction of ambient impact in all its phases of use. The creation, the development and the confection of new junction elements were described, and case studies of new products developed specifically with this purpose were presented.展开更多
为解决耕整播一体机作业过程中面临的土壤回填和碎土效果不佳,以及耕作阻力较大等问题,该研究基于鲨鱼背鳍的轮廓曲线设计了一种仿生直刃旋耕刀。通过高斯方程对背鳍轮廓进行拟合,结果显示拟合决定系数R2接近1且残差平方和SSE(sum of sq...为解决耕整播一体机作业过程中面临的土壤回填和碎土效果不佳,以及耕作阻力较大等问题,该研究基于鲨鱼背鳍的轮廓曲线设计了一种仿生直刃旋耕刀。通过高斯方程对背鳍轮廓进行拟合,结果显示拟合决定系数R2接近1且残差平方和SSE(sum of squares of the residuals)值接近0,验证了所用函数方程的优越性及数据预测的准确性。借助离散元仿真软件,以刀辊回转速度n、机具前进速度v和耕作深度h为因素,以回填率Pr、碎土率I和耕作阻力F为指标,进行二次正交旋转组合仿真试验。结果显示,当刀辊回转速度为241 r/min,机具前进速度为0.65 m/s,耕作深度为120 mm时,仿生旋耕刀-土壤颗粒接触模型具有最优解。室内土槽试验进一步验证,仿生旋耕刀回填率为84.34%,碎土率为79.7%,平均耕作阻力为87.25N,在同等运动参数条件下相较于直刃刀、弯形刀和凿形刀,回填率分别提升了11.98%、36.62%、23.2%;碎土率分别提升了15.07%、6.89%、10.32%;耕作阻力分别降低了15.59%、28.83%、24.38%,并且各指标与仿真结果的相对误差分别为3.7%、3.2%和4.5%,仿真试验和室内土槽试验结果表明仿生旋耕刀在减少耕作阻力的同时,可提高带状旋耕作业的回填率和碎土率,验证了设计的正确性。研究结果可为带状旋耕装置的研发与优化提供支撑。展开更多
The lightweight and high efficiency of natural structures are the inexhaustible sources for engineering improvements. The goal of the study is to find innovative solutions for mechanical lightweight design through the...The lightweight and high efficiency of natural structures are the inexhaustible sources for engineering improvements. The goal of the study is to find innovative solutions for mechanical lightweight design through the application of structural bionic approaches. Giant waterlily leaf ribs and cactus stem are investigated for their optimal framework and superior performance. Their structural characteristics are extracted and used in the bio-inspired design of Lin MC6000 gantry machining center crossbeam. By mimicking analogous network structure, the bionic model is established, which has better load-carrying capacity than conventional distribution. Finite Element Method （FEM） is used for numerical simulation. Results show better specific stiffness of the bionic model, which is increased by 17.36%. Finally the scaled models are fabricated by precision casting for static and dynamic tests. The physical experiments are compared to numerical simulation. The results show that the maximum static deformation of the bionic model is reduced by about 16.22%, with 3.31% weight reduction. In addition, the first four natural frequencies are improved obviously. The structural bionic design is a valuable reference for updating conventional mechanical structures with better performance and less material consumption.展开更多
Extenics is a newly developed interdisciplinary subject combining mathematics, philosophy and engineering. It provides useful formalized qualitative tools and quantitative tools for solving contradictory problems. In ...Extenics is a newly developed interdisciplinary subject combining mathematics, philosophy and engineering. It provides useful formalized qualitative tools and quantitative tools for solving contradictory problems. In this paper, extension theory is introduced briefly and the primary applications of this theory and methods in bionic engineering research are discussed. The extension model of biological coupling functional system is established. In order to identify the primary and secondary sequencing of coupling elements, the Extension Analytic Hierarchy Process (EAHP) was adopted to analyze the contribution of each coupling element to the coupling functional system. Thus, the influence weight factor of each coupling element can be determined, so as to provide a new approach for solving primary and secondary sequencing problem of coupling elements in a quantitative way, and facilitate the subsequent bionic coupling study.展开更多
针对三七收获作业时挖掘铲存在挖掘阻力大和能耗高等问题,以穿山甲前足爪趾为仿生原型,设计了一款高效减阻仿生挖掘铲。以三七根茎及种植土壤为研究对象,计算得本征物理参数,设置Bonding键参数建立三七根茎离散元模型,分析根土黏结机理...针对三七收获作业时挖掘铲存在挖掘阻力大和能耗高等问题,以穿山甲前足爪趾为仿生原型,设计了一款高效减阻仿生挖掘铲。以三七根茎及种植土壤为研究对象,计算得本征物理参数,设置Bonding键参数建立三七根茎离散元模型,分析根土黏结机理,利用Hertz-Mindlin with JKR建立三七根茎-种植土壤离散元复合模型;通过三维扫描获取穿山甲爪趾点云模型,并运用Solidworks建立仿生挖掘铲三维模型,根据爪趾三维模型设计仿生挖掘铲外形结构;对挖掘铲铲尖与铲柄进行力学分析,确定影响作业质量的设计参数;基于EDEM离散元法建立部件-土壤-作物多元仿真模型,以土壤颗粒速度矢量、土壤扰动率及挖掘阻力为评价指标进行仿真试验,得到不同指标的影响规律;通过台架试验验证仿生挖掘铲作业性能,获取仿生挖掘铲和平面挖掘铲平均挖掘阻力分别为1171.69、1442.36 N,平均减阻率为18.81%,台架与仿真试验结果基本一致。试验结果表明仿生挖掘铲具有良好减阻降耗特性,仿生结构设计合理,能满足酸性红土条件下三七收获挖掘作业。展开更多
文摘The applications of bionic methodology developed by the Laboratory of Design and Material Selection as basis in the creation of junction elements were demonstrated. These elements favor the application of Ecodesign in reference to the effectiveness of product dismount aiming the reduction of ambient impact in all its phases of use. The creation, the development and the confection of new junction elements were described, and case studies of new products developed specifically with this purpose were presented.
文摘为解决耕整播一体机作业过程中面临的土壤回填和碎土效果不佳,以及耕作阻力较大等问题,该研究基于鲨鱼背鳍的轮廓曲线设计了一种仿生直刃旋耕刀。通过高斯方程对背鳍轮廓进行拟合,结果显示拟合决定系数R2接近1且残差平方和SSE(sum of squares of the residuals)值接近0,验证了所用函数方程的优越性及数据预测的准确性。借助离散元仿真软件,以刀辊回转速度n、机具前进速度v和耕作深度h为因素,以回填率Pr、碎土率I和耕作阻力F为指标,进行二次正交旋转组合仿真试验。结果显示,当刀辊回转速度为241 r/min,机具前进速度为0.65 m/s,耕作深度为120 mm时,仿生旋耕刀-土壤颗粒接触模型具有最优解。室内土槽试验进一步验证,仿生旋耕刀回填率为84.34%,碎土率为79.7%,平均耕作阻力为87.25N,在同等运动参数条件下相较于直刃刀、弯形刀和凿形刀,回填率分别提升了11.98%、36.62%、23.2%;碎土率分别提升了15.07%、6.89%、10.32%;耕作阻力分别降低了15.59%、28.83%、24.38%,并且各指标与仿真结果的相对误差分别为3.7%、3.2%和4.5%,仿真试验和室内土槽试验结果表明仿生旋耕刀在减少耕作阻力的同时,可提高带状旋耕作业的回填率和碎土率,验证了设计的正确性。研究结果可为带状旋耕装置的研发与优化提供支撑。
基金Acknowledgements The research was sponsored by the Natural Science Foundation of China （50975012）, and the Scientific Research Foundation for the Outstanding Young Scientist of Shandong Province （2008BS05007）.
文摘The lightweight and high efficiency of natural structures are the inexhaustible sources for engineering improvements. The goal of the study is to find innovative solutions for mechanical lightweight design through the application of structural bionic approaches. Giant waterlily leaf ribs and cactus stem are investigated for their optimal framework and superior performance. Their structural characteristics are extracted and used in the bio-inspired design of Lin MC6000 gantry machining center crossbeam. By mimicking analogous network structure, the bionic model is established, which has better load-carrying capacity than conventional distribution. Finite Element Method （FEM） is used for numerical simulation. Results show better specific stiffness of the bionic model, which is increased by 17.36%. Finally the scaled models are fabricated by precision casting for static and dynamic tests. The physical experiments are compared to numerical simulation. The results show that the maximum static deformation of the bionic model is reduced by about 16.22%, with 3.31% weight reduction. In addition, the first four natural frequencies are improved obviously. The structural bionic design is a valuable reference for updating conventional mechanical structures with better performance and less material consumption.
基金support by the Key Project of National Natural Science Foundation of China (Grant No.50635030)
文摘Extenics is a newly developed interdisciplinary subject combining mathematics, philosophy and engineering. It provides useful formalized qualitative tools and quantitative tools for solving contradictory problems. In this paper, extension theory is introduced briefly and the primary applications of this theory and methods in bionic engineering research are discussed. The extension model of biological coupling functional system is established. In order to identify the primary and secondary sequencing of coupling elements, the Extension Analytic Hierarchy Process (EAHP) was adopted to analyze the contribution of each coupling element to the coupling functional system. Thus, the influence weight factor of each coupling element can be determined, so as to provide a new approach for solving primary and secondary sequencing problem of coupling elements in a quantitative way, and facilitate the subsequent bionic coupling study.
文摘针对三七收获作业时挖掘铲存在挖掘阻力大和能耗高等问题,以穿山甲前足爪趾为仿生原型,设计了一款高效减阻仿生挖掘铲。以三七根茎及种植土壤为研究对象,计算得本征物理参数,设置Bonding键参数建立三七根茎离散元模型,分析根土黏结机理,利用Hertz-Mindlin with JKR建立三七根茎-种植土壤离散元复合模型;通过三维扫描获取穿山甲爪趾点云模型,并运用Solidworks建立仿生挖掘铲三维模型,根据爪趾三维模型设计仿生挖掘铲外形结构;对挖掘铲铲尖与铲柄进行力学分析,确定影响作业质量的设计参数;基于EDEM离散元法建立部件-土壤-作物多元仿真模型,以土壤颗粒速度矢量、土壤扰动率及挖掘阻力为评价指标进行仿真试验,得到不同指标的影响规律;通过台架试验验证仿生挖掘铲作业性能,获取仿生挖掘铲和平面挖掘铲平均挖掘阻力分别为1171.69、1442.36 N,平均减阻率为18.81%,台架与仿真试验结果基本一致。试验结果表明仿生挖掘铲具有良好减阻降耗特性,仿生结构设计合理,能满足酸性红土条件下三七收获挖掘作业。
