Stody On Resistance Reduction Mechanism Based On Mole Cricket Claw Toe Structure

The main purpose of research on drag reduction of earth-touching parts of excavating machinery is to reduce the digging resistance and energy consumption.At present,bionic technology is more and more widely used in the research of drag reduction of soil contact parts.Mole cricket is a typical soil animal.After long-term evolution,it has an efficient digging ability.The special structure of mole cricket claw toe provides a good imitation object for the design and optimization of resistance reduction of earth-touching parts.Through studying the structural characteristics of mole cricket claw toe,this paper aims to analyze the role of its special configuration in excavation movement and drag reduction-The structure information of claw toe was obtained by embedding section.By extracting the contour curve of claw toe section,3d model reconstruction of claw toe was conducted in Rhino3D.The characteristic curve of drag reduction was extracted from the model,the curve fitting equation was obtained by using polynomial function,and the curve was analyzed by using the second derivative and curvature of the fitting equation.Then,the method of experimental optimization design was applied to design the model.With the four-pyramid as the prototype,all the extracted characteristic factors were sorted out,a three-factor and four-level table was established,and L16(45)orthogonal table was selected to determine the design scheme.In solidworks,16 sample models were designed according to the bionic design scheme.The sample was made with a 3D printer and the final size of the sample was determined according to the size and range of the test bed,which was about 12.5 times the actual size of the claw toe.Horizontal traction test was carried out in the indoor resistance test bench.The depth of penetration was set as 15mm and the forward speed was set as 10mm/s.Three tests were carried out for each sample,and the mean resistance was taken as the final result of the resistance of the sample.The results showed that sample 16 received the highest resistance,about 39.79n,and sample 12 received the lowest resistance,about 19.08n,which was about 51%lower than the two.By using range method and variance method to analyze the test data,it was found that the significant level of the influence of the cross-section contour on the cutting resistance was 0.25.The left part of the claw 1 top view contour,the profile curve of claw 3 longitudinal section and the right part of the profile curve of claw 1 cross section were the optimal design combination,and the drag reduction was the most obvious.The finite element software ANSYS/LS-DYNA was used to simulate the soil cutting of 16 samples and analyze the resistance curve of each sample under the same condition.The results showed that sample 16 suffered the most resistance and sample 12 the least,which was consistent with the real results.By comparing the stress of all samples at the same time,it is found that the design of profile profile and cross-section profile has good drag reduction effect.The research on the drag reduction mechanism of mole cricket claw toe in this paper provides a certain theoretical basis for the drag reduction design of earthing touching parts.