The mechanical and frictional properties of different parts of the elytra of five species of beetle were measured using a nano-indenter and a micro-tribometer. The surface microstructures of the elytra were observed b...The mechanical and frictional properties of different parts of the elytra of five species of beetle were measured using a nano-indenter and a micro-tribometer. The surface microstructures of the elytra were observed by optical microscopy and scanning white light interferometry. The surface microstructures of the elytra of all five species are characterized as non-smooth concavo-convex although specific morphological differences demonstrate the diversity of beetle elytra. Young＇s modulus and the hardness of the elytral materials vary with the species of beetle and the sampling locations, ranging from 1.80 GPa to 12.44 GPa, and from 0.24 GPa to 0.75 GPa, respectively. In general, both the Young＇s modulus and the hardness are lower in samples taken from the center of the elytra than those taken from other regions, which reflects the functional heterogeneity of biological material in the process of biological evolution. The elytra have very low friction coefficient, ranging from 0.037 to 0.079, which is related to their composition and morphology. Our measurements indicate that the surface texture and its mi- crostructural size of beetle elytra contribute to anti-friction effects.展开更多
Lightweight materials, structures and coupling mechanisms are very important for realizing advanced flight vehicles. Here, we obtained the geometric structures and morphologies of the elytra of beetles and ascertained...Lightweight materials, structures and coupling mechanisms are very important for realizing advanced flight vehicles. Here, we obtained the geometric structures and morphologies of the elytra of beetles and ascertained its coupling zone by using the histological section technique and SEM. We set up a three-dimensional motion observing system to monitor the opening and closing behaviour of elytra in beetles and to determine the motion mechanism. We constructed a force measuring system to measure the coupling forces between elytra. The results show that elytra open and close by rotating about a single axle, where the coupling forces may be as high as 160 times its own bodyweight, the elytra coupling with the tenon and mortise mechanism, surface texture and opening angle between elytra heavily influence the coupling forces. These results may provide insights into the design mechanism and structure for future vehicles of flight.展开更多
基金The authors acknowledge financial support from the National Nature Science Foundation of China
文摘The mechanical and frictional properties of different parts of the elytra of five species of beetle were measured using a nano-indenter and a micro-tribometer. The surface microstructures of the elytra were observed by optical microscopy and scanning white light interferometry. The surface microstructures of the elytra of all five species are characterized as non-smooth concavo-convex although specific morphological differences demonstrate the diversity of beetle elytra. Young＇s modulus and the hardness of the elytral materials vary with the species of beetle and the sampling locations, ranging from 1.80 GPa to 12.44 GPa, and from 0.24 GPa to 0.75 GPa, respectively. In general, both the Young＇s modulus and the hardness are lower in samples taken from the center of the elytra than those taken from other regions, which reflects the functional heterogeneity of biological material in the process of biological evolution. The elytra have very low friction coefficient, ranging from 0.037 to 0.079, which is related to their composition and morphology. Our measurements indicate that the surface texture and its mi- crostructural size of beetle elytra contribute to anti-friction effects.
基金State"973"Programs from the Ministry of Science and Technology of China (GrantNo.2007CB607600)National Natural Science Foundation of China (GrantNos.60535020 and 50635030)
文摘Lightweight materials, structures and coupling mechanisms are very important for realizing advanced flight vehicles. Here, we obtained the geometric structures and morphologies of the elytra of beetles and ascertained its coupling zone by using the histological section technique and SEM. We set up a three-dimensional motion observing system to monitor the opening and closing behaviour of elytra in beetles and to determine the motion mechanism. We constructed a force measuring system to measure the coupling forces between elytra. The results show that elytra open and close by rotating about a single axle, where the coupling forces may be as high as 160 times its own bodyweight, the elytra coupling with the tenon and mortise mechanism, surface texture and opening angle between elytra heavily influence the coupling forces. These results may provide insights into the design mechanism and structure for future vehicles of flight.
