Additive Fabrication of Soft Robotics

Additive manufacturing, which is the process of fabrication through printing, brings new opportunities in the field of soft robotics. It enables the fabrication of complex structures that cannot be fabricated without post-assembly, including making objects composed of multi-materials. Here we describe new materials and processes for making soft grippers with embedded sensors, starting from a solution of monomers and oligomers, and dispersion systems. The resulting highly stretchable polymers are utilized to print pneumatic actuators, which are the main component of soft grippers. Furthermore, several responsive materials will be presented, which bring sensing abilities, towards the fabrication of autonomous soft grippers. The sensing is obtained by unique designs of the grippers with embedded electrically conductive materials, or by meta-materials based-design of optical sensors. These grippers can adapt to different shapes, apply holding forces tailored to the object's mechanical properties, and provide feedback to the control system for optimal operation, as will be demonstrated for several practical examples.