Zhang Hao,He Qing-song,Tian Cheng-bo,Wu Yu-wei,Zhao Ze-fang,Yu Min
Inspired by the microstructure of gecko’s toe, two kinds of polyvinyl chloride (PVC) gels with different modulus were poured on a silicon mold with micropillars, and then a bio-inspired adhesive with variable modulus was manufactured in this study. The adhesions of variable modulus and fixed modulus bio-inspired adhesives were tested, respectively, on a smooth glass and a printed circuit board (PCB) with different surface structures. The results show that PVC gel bio-inspired adhesives with variable modulus have many advantages compared with the fixed modulus bio-inspired adhesives. The adhesion of variable modulus bio-inspired adhesives on the rough PCB surface increased by 2–5 times, and due to the use of variable modulus of PVC gel, the surface micropillars can maintain high aspect ratio and flexible tips at the same time. Moreover, the use of PVC gel makes it easier to demold during the bio-inspired adhesives preparation. An adhesion-desorption device was made according to the movement of the gecko toes, and the PCB was successfully grasped.
Xinyuhang Zhang,Wei Liao,Yunpeng Wang,Zhongqiang Yang
Graphical A compressible and omnidirectional gripper is constructed using a liquid crystal elastomer foam rod. The compressed gripper enters a slit and grasps and moves hot objects to a safe place, demonstrating its potential for emergency disposal. The reported simple design for gripper construction can enhance the functions of soft robots. Liquid crystal elastomers (LCEs) are considered to be a promising material for the fabrication of soft grippers because of their large and reversible deformations, an LCE gripper with suitable compressibility and omnidirectionality has not yet been developed. To overcome these obstacles, this study utilizes salt template method to fabricate a rod-like LCE foam as gripper. The thickness of the compressible foam can be reduced by up to 77%, temporarily maintaining the deformation and enabling the gripper to pass through slits. The foam was aligned along the long axis and the length of the foam exhibits reversible thermal responsiveness and contract up to 57% along its alignment. Additionally, when the foam approaches a heat source, the generated temperature gradient results in a contraction gradient owing to the low thermal conductivity of the LCE foam. This in turn causes the foam to reversibly bend with a bending angle up to 93° and follow the movement of a heat source omnidirectionally. The developed gripper successfully grasps, moves, and releases hot objects in a cold and safe place, demonstrating its potential for emergency disposal. Thus, LCE foams can be considered suitable materials for novel gripper design and construction.
危险品化学品经营许可证（带存储）