Research On Snail Adhesion Theory And Biomimetic Design Of Adaptive Adsorption Device

Adhesion plays an important role in robot operations,especially effective for gripping slippery and fragile items with robotic hands or fingers.In view of the limitations of traditional vacuum and electromagnetic adsorption,it is of great significance to develop a self-adaptive adsorption or grasping device in multi environment to improve the efficiency and expand the scope of robot operation.Snails can freely adhere and crawl on a variety of environments and surfaces,and its potential adaptive adhesion mechanisms will provide new ideas for the development of adsorption devices.In this thesis,the snail is adopted as the bionic object,and the adaptive adhesion mechanisms of snails is explored systematically.Based on the snail’s adhesion force,the deformation of gastropods,and the micromorphology and rheological properties of mucus,we analyze and discuss the synergy between the gastropod and mucus.The results show that the snail’s gastropods can form a negative pressure cavity through the large deformation of its gastropods,coupling the adhesion between bristles and mucus,enhancing its adhesion performance and adapting to various surfaces.On this basis,a new type of suction cup that can adapt to three-dimensional surface is designed.It is found that the suction cup can adapt to different environments and the surface through two working modes: bottom film adhesion and negative pressure assisted adsorption.The influence of suction cup structure and backing stiffness on adhesion performance is numerically simulated.Then,we explore the preparation process of sucker,systematically investigate the effect of the film material,Filling particles,pressure difference,pre-load,preinflation on the adhesive force,and study the adsorption performance of sucker on curved surfaces,discontinuous surfaces,underwater and under oil,which verify the feasibility of the sucker for a variety of adhesive environment and surfaces.In addition,in order to improve the effect of uniform load distribution,two kinds of sucker with different microstructures film are further designed,and the adhesion effect of the suction cup is investigated.The results show that although the adhesion performance of the suction cup withmicrostructures on the bottom film decreases,it can improve the load uniformity of the adhesion interface,which is beneficial to improve the utilization efficiency of the suction cup for the pressure difference.Finally,a flexible manipulator is designed,and the three working mode of the suction cup:pneumatic suction,the soft film adhesion and negative pressure assisted adsorption,can be freely converted by the adjusting device.Furthermore,we carried out adsorption and grasping experiments with the manipulator.