摘要
为提高松软地面步行机构及农业机械的通过性能,以中华绒螯蟹步足的指节结构为生物原型,加工3种不同锥度的仿生锥形触土部件,并将圆柱触土部件作为对比试样。通过触土部件在干沙中的水平阻力测试,分析了速度、入土深度和锥角3种因素对触土部件土壤阻力的影响。研究发现,水平阻力随触土部件入土深度和锥角的增加而显著增大,呈2次方关系,水平阻力随锥角增大最多可提高167.57%;速度小幅线性增大时,速度的增加使水平阻力最多增大11.37%,仿生锥形试样比圆柱试样具有更高的推进效率。结合试验结果和ALBERT提出的圆柱杆土壤阻力估计式,建立了用于预测等截面触土部件与变截面触土部件土壤阻力的计算式,并将计算值与试验值进行对比分析。结果表明,二者残差低于3.62 N,平均相对误差小于22.77%,具有较高的准确性。
Vehicles and agricultural machinery are often trapped caused by slipping and sinkage when working on soft terrain. Therefore,a superior propulsive performance is significant for the vehicle. By observation of the dactylopodites of Chinese mitten crab,three bionic soil contact parts with different cone angles were fabricated. The article focused on the drag force in the horizontal movement of soil contact parts,which were compared with cylinder sample. Experiments of walking foot were carried out in soil-bin filled with fine quartz sand. The influence of motion velocity,insertion depth and cone angle to the drag force were analyzed. Results showed the drag force was increased with the square of insertion depth and the cone angle of soil contact part. When the cone angle of bionic walking foot was doubled and trebled,the drag forces were increased by 47. 18% to 167. 57%. And the drag force was linearly correlated with motion velocity. In the scope of velocity of experiments,the drag force was increased by 11. 37% at most with the increasing velocity. A model for predicting the drag force of walking foot was created based on the estimating formula proposed by ALBERT,and was combined with the experimental results. The verification of the model showed that the residual was not higher than 3. 62 N and the average relative error between the model calculation values and experimental data was lower than 22. 77%. Thus the model can be used for both variable section and equal section soil contract part,and it was accurate enough in the prediction of the drag force. The research results provided theoretical basis for predicting the performance of propulsion of the soil contact part and the development of legged mechanisms on soft terrain.
出处
《农业机械学报》
EI
CAS
CSCD
北大核心
2016年第S1期124-129,共6页
Transactions of the Chinese Society for Agricultural Machinery
基金
国家自然科学基金项目(51375199)
关键词
仿生
触土部件
变截面
阻力模型
bionic
soil contact part
variable section
drag force model
