Active friction control in lubrication condition using novel metal morphing surface

摘要

We propose a new active friction control method with a morphing surface using a unique diaphragm structure consisting of 60-um thin metal film. In poor lubrication, the friction coefficient dropped significantly from 0.19 to 0.03 when the surface changed from concave to convex. Optical in situ observations revealed that the oil collected at the convexity due to capillary force and meniscus. In addition, results of electric characteristic measurements revealed that the solid contact area decreased with the convexity. In conclusion, the reduction of solid contact due to improvement of lubrication condition was likely the friction reduction mechanism of the convex shape. Because active friction control realizes minimal friction loss and multifunctionality, the morphing surface can contribute to future machine development.