The aim of this work is to present the development of a bio-inspired approach for a robotic tail using Macro Fiber Composites (MFC) as actuators. The use of this technology will allow achieving closer to the nature approach of the tail, aiming to mimic a bird tail behavior. The tail will change its shape, performing morphing, providing a new type of actuation methodology in flapping control systems. The work is intended as a first step for demonstrating the potential of these technologies for being applied in other parts of the aerials robotics systems. When compared with traditional actuation approaches, one key advantage that is given by the use of MFC is their ability to adapt to different flight conditions via geometric tailoring, imitating what birds do in nature. Theoretical explanations, design, and experimental validation of the developed concept using different methodologies will be presented in this paper.

The use of aerial systems in a variety of real applications is increasing nowadays. These offer solutions to existing problems in ways that have never seen before thanks to their capability to perform perching, grasping or manipulating in inaccessible or dangerous places. Many of these applications require small-sized robots that can maneuver in narrow environments. However, these are required to have also strength enough to perform the desired tasks. This balance is sometimes unreachable due to the fact that traditional servomotors are too heavyweight for being carried by such small unmanned aerial systems (UAS). This paper, offers a innovative solution based on twisted and coiled polymers (TCP) muscles. These tensors have a high weight/strength ratio (up to 200 times) compared with traditional servos. In this work, the practical and modeling work done by the authors is presented. Then, a preliminary design of a bio-inspired claw for an unmanned aerial system (UAS) is shown. This claw has been developed using additive manufacturing techniques with different materials. Actuated with TCP, it is intrinsically compliant and offers a great force/weight ratio.