Silicone based artificial skin for humanoid facial expressions

摘要

Artificial skin materials were synthesized using platinum-cured silicone elastomeric material (Reynolds Advanced Materials Inc.) as the base consisting of mainly polyorganosiloxanes, amorphous silica and platinum-siloxane complex compounds. Systematic incorporation of porosity in this material was found to lower the force required to deform the skin in axial direction. In this study, we utilized foaming agents comprising of sodium bicarbonate and dilute form of acetic acid for modifying the polymeric chain and introducing the porosity. Experimental determination of functional relationship between the concentration of foaming agent, slacker and non-reactive silicone fluid and that of force -deformation behavior was conducted. Tensile testing of material showed a local parabolic relationship between the concentrations of foaming agents used (per milliliter of siloxane compound) and strain. This data can be used to optimize the amount of additives in platinum cured silicone to obtain desired force - displacement characteristics. Addition of "silicone thinner" and "slacker" showed a monotonically increasing strain behavior. A mathematical model was developed to arrive at the performance metrics of artificial skin.