surface tension, capillary, bearing, wetting
Digital Object Identifier (DOI)
While capillary forces are negligible relative to gravity at the macroscale, they provide adequate force to effectively manipulate millimeter to micro meter objects. The fluidic actuation can be accomplished using droplets that also act as bearings. While rotary droplet bearings have been previously demonstrated, this paper addresses the positioning accuracy of a droplet-based bearing consisting of a droplet between a moving plate and a stationary substrate with constrained wetting region under a normal load. Key wetting cases are analyzed using both closed form analytical approximations and numerical simulations. The vertical force and stiffness characteristics are analyzed in relation to the wetting boundaries of the supporting surface. Case studies of different wetting boundaries are presented and summarized. Design strategies are presented for maximizing load carrying capability and stiffness. These results show that controlled wetting and opposing droplet configurations can create much higher stiffness fluidic bearings than simple droplets.
This work is licensed under a Creative Commons Attribution 4.0 License.
Was this content written or created while at USF?
Citation / Publisher Attribution
Micromachines, v. 9, art. 252
Scholar Commons Citation
Ni, Qi and Crane, Nathan, "Controlling Normal Stiffness in Droplet-Based Linear Bearings" (2018). Mechanical Engineering Faculty Publications. 219.