Magnetic Assembly of Soft Robots with Hard Components

This paper describes the modular magnetic assembly of reconfigurable, pneumatically actuated robots composed of soft and hard components and materials. The soft components of these hybrid robots are actuators fabricated from silicone elastomers using soft lithography, and the hard components are acrylonitrile-butadiene-styrene (ABS) structures made using 3D printing. Neodymium-iron-boron (NdFeB) ring magnets are embedded in these components to make and maintain the connections between components. The reversibility of these magnetic connections allows the rapid reconfiguration of these robots using components made of different materials (soft and hard) that also have different sizes, structures, and functions; in addition, it accelerates the testing of new designs, the exploration of new capabilities, and the repair or replacement of damaged parts. This method of assembling soft actuators to build soft machines addresses some limitations associated with using soft lithography for the direct molding of complex 3D pneumatic networks. Combining the self-aligning property of magnets with pneumatic control makes it possible for a teleoperator to modify the structures and capabilities of these robots readily in response to the requirements of different tasks.