Adjustable Friction Force of Elastic Post via Regulating Internal Cavity Pressure

Abstract

The objective of this study is to investigate and obtain an adjustable friction force between an elastic polymeric post with cavity and a rigid, smooth, flat surface. Elastic cylindrical posts made of polymers are generally used as surface texturing components. In this study, the friction force of the elastic cylindrical posts with a flat tip in contact with a smooth and rigid surface was adjusted by a pneumatic-based actuation system. Finite-element based simulation was performed to adjust the friction force of the cylindrical posts by pressurizing the inner cavity of the posts. The frictional contact between the elastic posts and the counter rigid surface was modeled using the Amontons-Coulomb friction law, neglecting the adhesive contribution. The friction force amplitude was calculated with different cavity dimensions of the elastic posts and different cavity pressure values. The results show that the presence of an internal cavity reduces the friction force, and the cavity diameter has more influence on the reduction of the friction force than the cavity height. In conclusion, regulating the cavity pressure was shown to be an effective method of adjusting the friction force.