Characteristic, Function, Mechanics And Bionic Analysis Of Oriental Mole Cricket (Gryllotalpa Orientalis Burmeister)

The geometric shape of soil animal's legs are all adapt to their living surroundings through their volution over millions of years. The oriental mole crickets, such as Gryllotalpa orientalis Burmeister, can walk fast, swim, fly, dig in earth and tweet, and can bore the holes in mud without any soil adhesion on it's body surfaces. The especial fossorial legs of the oriental mole cricket have very high efficiency in digging in earth. Analysis of the morphological characteristics of the oriental mole cricket is very important to the further theoretical research and technological development of soil-engating components of such terrain machinery as agricultural machine.The adult oriental mole crickets Gryllotalpa orientalis Burmeister were collected in Dehui city of Jilin Province, China. The size of the mole cricket's body was measured with a stereomicroscope with a software for automatic calculation function and the body-foot layout ratios of the oriental mole cricket were calculated. The point clouds of head, pronotum, forewings and legs of the oriental mole cricket surface were obtained by a 3D scanner. The data of the point clouds were precessed using the Imageware software, the curved surface of the oriental mole cricket's surfaces were reconstructed. The mouthpart of the oriental mole crickets were reconstructed using the slicing method. Utilize Coreltrace software and Imageware software to get the characteristic curve data of the forelegs, pronotum and forewings of the oriental mole crickets were fitted with Matlab software. The corresponding curve equations were obtained and the second derivative and curvature were calculated.The geometrical characteristics of the surface of oriental mole cricket in microscale were examined by stereomicroscopy and scanning electronic microscopy (SEM). The seta covering density on the pronatum, abdomen, legs, hindwing, forewing of the oriental mole crickets were determined using the measurement method of the content of the second phase area. The growing orientations of the seta respect to the body were analyzed. The cross-sections geometrical morphologies of the oriental mole cricket's foreleg claw toes and mouthpart were examined by SEM and it was found that the both have empty structure inside them. The cross-section area of empty structure was measured using the slicing method and their ratios to the whole cross-section area were calculated. The composition of the oriental mole cricket's cuticle was examined with JSM-5301 energy spectrometer and the relativity of the cuticle composition with its founction was analyzed.The contact angle of water on the cuticle surfaces of the oriental mole cricket with a contact angle measurement apparatus (OCA20) it was found that the oriental mole cricket body surfaces possess hith hydrophobicity and there exists close relationship with the seta covering density.The nanomechanics properties of the cuticle surfaces of the foreleg claw toe and mouthpart of the oriental mole cricket were examined with a nanomechanics testing system (Hisitron) and the nano-hardness and elastic modulus were measured. It was from comparing the nano-hardness of the cuticle surfaces of the oriental mole cricket with the foreleg femur cuticle of dung beetle Copris ochus Motschulsky and the cuticle of bovine hoof wall of cattle, pig and sheep that the nano-hardness of the cutlcles the foreleg claw toe and mouthpart of the oriental mole cricket are higher than the culticle of the foreleg femur cuticle of dung beetle Copris ochus Motschulsky and the cuticle of bovine hoof wall of cattle, pig and sheep.The models of the foreleg claw toe of the oriental mole cricket, without and with empty structure, were established employing Inventor software as modeling tool and the position with the largest stress was determined by finite element method with ANSYS software. It was found that the model toe with empty structure has better mechanic property than the model toe without empty structure. According to the conventional scales of the requirement of the excavator teeth, the conventional tooth model was established and the biomimetic tooth was designed based on geometrical structure of the vertical section of the foreleg claw toe of the oriental mole cricket. The simulation analysis of the conventional tooth and the biomimetic tooth models were conducted and it was found that the biomimetic tooth had higher excavating property than the conventional tooth under identical testing conditions.The biomimetic tooth model and conventional tooth model were manufactured utilizing FDM-Dimension rapid molding system. The linking parts of tooth part with test transmission attachment were designed The excavating tests of the biomimetic tooth were run in an indoor soil bin (The Key Laboratory of Bionics Engineering, Jilin University, P. R. China) as compared to the conventional tooth. The tests showed the same conclusions as the simulation.