Bioinspired film-terminated ridges for enhancing friction force on lubricated soft surfaces

Enhancing friction force in lubricated, compliant contacts is of particular interest due to its wide application in various engineering and biological systems. In this study, we have developed bioinspired surfaces featuring filmterminated ridges, which exhibit a significant increase in lubricated friction force compared to flat samples. We propose that the enhanced sliding friction can be attributed to the energy dissipation at the lubricated interface caused by elastic hysteresis resulting from cyclic terminal film deformation. Furthermore, increasing inter-ridge spacing or reducing terminal film thickness are favorable design criteria for achieving high friction performance. These findings contribute to our understanding of controlling lubricated friction and provide valuable insights into surface design strategies for novel functional devices.