Adhesion force evaluation of suction cup on different softness of target surface

Abstract

We evaluated adhesion force of suction cup on different softness of target surface. For flexible devices attachable to human bodies, suction cups have superior properties to other conventional attachment mechanisms, because they enable to use repeatedly and show relatively high adhesion forces. However, suction cup can generally adhere to hard and flat surface, so it is difficult to attach them to soft surface. Therefore, we focused on deformation mode of suction cup. We revealed that spring constant is changed by adhesion surface because deformation of suction cup is different on adhesion surface. So, we measured adhesion force by changing young’s modulus of suction cup, which is considered one of the parameters. We found that the lower the Young's modulus was, the smaller the preload required for the suction cup to initiate attachment was. In addition, we figured out that that when the suction cups had the same shape, the maximum adhesion forces decrease when Young's modulus of suction cups increase.