Design and Fabrication of Long Soft-Robotic Elastomeric Actuator Inspired by Octopus Arm

The biomimetic soft robotic actuators can provide stable flexible multi-point contact to safely grip delicate objects. A lot of soft robotic actuators have been fabricated using silica gel materials through molding methods. However, owing to the difficulty of the demolding process, existing soft robotic arms are often designed to be short. To fabricate a long soft robotic arm, this paper proposes a novel design approach for fabricating the long soft robotic arm (1000 mm) inspired by the octopus arm that is a fiber-reinforced pneumatic elastomeric actuator. First, we develop a set of molds of the long soft robotic elastomeric actuator. To easily achieve the demolding of the soft actuator chamber, we design the three core petals around the mandrels in the molds. Furthermore, there are also two half-segment mandrels. The two half-segment mandrels are respectively removed from both ends of the mold when demolding. Then, we manufacture the long soft robotic arm using the molds by the combination silica gel and non-extensible materials. We also perform the experiments to verify the feasibility of the long soft robotic elastomeric actuator. The experimental results show the proposed design method for fabricating the long soft robotic arm is feasible.