仿豆天蛾幼虫充气薄膜管弯曲特性研究

受豆天蛾幼虫体壁结构有较强的抗弯稳定性启发,设计了仿生充气管,以提高其弯曲特性。制作豆天蛾幼虫体壁组织切片,观察其体壁与附近肌肉组织的连接方式以及肌肉组织的分布形式,以此为依据设计了加筋充气管。通过有限元仿真和试验分析了普通充气管和加筋充气管在不同压力下的弯曲特性,获得了不同充气压力下横向载荷-位移关系曲线以及充气管弯曲极限载荷与充气压力的关系曲线。结果表明:在所选压力范围内,充气管的极限载荷与充气压力呈正比,加强筋的存在提高了充气管的弯曲特性,同时仿真结果表明,45°加载时加筋充气管的抗弯能力较0°加载时更强,两者均高于无加强筋时的抗弯能力。

Bending Characteristics of Inflatable Tube Bioinspired from Clanis bilineata Larva

The body wall structure of Clanis bilineata larva exhibits a strong stability under bending load. This characteristic prompted the development of a new inflatable tube to improve the stability under bending load. The Clanis bilineata larva was chosen to observe the connection between its body wall and nearby muscle tissues, as well as the distribution of these tissues, by using the tissue section technique. The Clanis bilineata larva can be simplified as a telescopic cylinder with folds and depressions. A large number of axial muscle tissues were found on the inner cylinder, which were uniformly distributed near the cylinder and divided into several sections in the axial direction. Between adjacent sections, a close connection to the body wall was formed. The distribution of the circular muscle tissues was relatively dense, and the distribution in the reticular structure enhanced the mechanical strength of the whole insect body and improved the stability of the structure. This structure simultaneously became a barrier to reduce impact from the outside world on the internal organs and ensured the normal physiological activities of the Clanis bilineata larva. Inspired by this, an inflatable tube with reinforcing ribs was designed. Simulation using the finite element method and experimentation were employed to analyze the bending characteristics of the inflatable tube with and without reinforcing ribs under different pressures. Results indicated that the ultimate load of both inflatable tubes was increased linearly with the increase of pressure;the existence of reinforcing ribs can improve the bending characteristics of the tube, at the same time, the simulation results showed that the bending capacity of inflatable tube with reinforcing ribs was stronger when loading at 45° angle than that at 0° angle, both of which were higher than that without reinforcing ribs.