Soft robotics, where the arms of a robot are flexible as opposed to being made of rigid tubes and boxes, is gaining ground. Silicone (not silicon), a soft, rubbery material is a good choice for soft robotics. Typically, additive manufacture of silicones is through the ‘extrusion method’, which is not good, as the silicone ends up containing pores, which in turn affects the mechanical properties of the printed parts.
A team of researchers from IIT Mandi and Hannover University, Germany, have demonstrated 3D printing of silicone using a different technique of additive manufacturing, called material jetting—a method suitable for 3D printing of viscous materials. When they printed silicone in this way, they found it contained “almost negligible” pores.
This makes silicone a potential material for soft robotics applications when printed using the ‘material jetting’ process as not many commercially available 3D printers can print silicone with level of hardness. The silicone thus produced “not only withstands a moderate force but possesses compliance or flexibility which is integral for soft robots,” the researchers, Dr Sudhanshu Gangwar et al, say in their paper published in Materials Letters.
However, they recommend that this material be used in applications that has “low to moderate force” of about 30 Newtons.