Characterization of Silicone Rubber/MgO Nanocomposites for Grippers in Transmission Line Inspection Robots

The effect of addition of nanoparticles to silicone rubber is studied in this paper in the context of soft robotic applications to transmission line maintenance. Silicone rubber and polylactic acid (PLA) are used in the fabrication of these robotic structures. Desirable characteristics for the materials making the structure are (i) Low surface charge and space charge accumulation and (ii) High tensile and tear strength. To meet these requirements, addition of nano MgO to silicone rubber is proposed and studies pertaining to surface potential variation, space charge variation and dielectric parameters are performed. It is observed that 3wt% MgO added silicone rubber shows better performance than pure silicone rubber. Further, silicone rubber/MgO nanocomposite sandwiched PLA shows least space charge at the electrodes and at the interfaces of the sandwich. Moreover, the mechanical properties are also enhanced via the addition of nano MgO. In particular, 3wt% MgO added silicone rubber shows maximum tensile and tear strength. A direct correlation between tear strength and Shore A hardness is also observed. In addition, substantial improvement in viscoelastic properties of silicone rubber is observed with the addition of nano MgO.