Miniature tactile elements for tactile display with high stiffness resolution with magnetorheological fluid

Abstract

This paper describes miniature tactile elements with the dimension of a few mm for stiffness representation. The elements encapsulate magnetorheological (MR) fluid inside the flexible polydimethylsiloxane (PDMS) membrane and change its stiffness by controlling an external magnetic field. Hollow hemispherical PDMS membrane with the diameter of 4 mm was fabricated with glycerin droplet and filled with MR fluid. The elements were evaluated with compression tests. From the results, the elements successfully changed its stiffness and represent stiffness of normal tissues and tumors. Tactile display that consists of the elements were also evaluated. From the results, magnetic field to one element affected other elements. However, the difference was smaller than minimum detectable stiffness difference.