Dhayanithi Niteesh supervised by Dr. Aftab M Hussain received his  Master of Science –  Dual Degree in Electronics and Communication Engineering  (ECD). Here’s a summary of his research work on Towards Fabrication and Characterization of Dielectric Elastomeric Actuator based Flapping wing:

People are always in search of viable artificial (man-made) alternatives for all the naturally occurring ones, a quest started with artificial muscles, which have a wide range of applications from prosthesis to robotics.For this to happen, we are in dire need of electronics that are bendable,stretchable,etc. This is where the research field of Flexible Electronics pitches in, the focus of the work here is to study a specific type of actuators called the Dielectric Elastomeric Actuators (DEA) and how they can be successfully used in making artificial muscles, even though making of artificial muscles is far away, many preliminary advancements and tests have to be performed on the technology of interest to make sure it is suitable and can act as a viable replacement. So the present focus is that to try and construct the basic Building blocks required to reach the end goal of achieving fully functional artificial muscles.For the DEA, there are a lot of considerations to be made in the process starting from the type of materials to be used,to the process of building them all.All of the above aspects are to be studied and experimented, to progress towards the end goal. Literature search on DEA’s and the field of Flexible Electronics itself was done to get the gist of the field and for a comprehensive knowledge gain so that all the basic elements and path to be followed is crystal clear right from the beginning. Along with the substrate and other components, the conductive materials used in these also have to endure the applied strain, hence, thin film based conductors are being studied extensively. We report bending behavior of conductive CNT-PDMS thin film channels. Transmission Line Method (TLM) based resistance calculations have been done to precisely analyze the CNT thin film sheet resistance and the contact resistance.This exercise allows us to look at the effectiveness of CNT channels as a conductive path and also helps us understand their behavior over concentration, path length and strain caused due to bending. We report sheet resistance values of 254 Ω/2 and 1.41 Ω/2 for thin films of two different CNT concentrations. The contact resistances for these films were 230 Ω and 315 Ω respectively. We observed that bending induced strain caused the resistance values to increase from 3.95 kΩ for flat to 13.1 kΩ for bending radius of 1.2 cm. Our work towards artificial muscles is an attempt at biomimetic technologies which are an important part of soft robotics. Researchers have been developing and improving many such technologies ranging from prosthetics to artificial skin. We make a step towards fully functional muscles by presenting the fabrication and characterization of an artificial muscle flapping wing using dielectric elastomer actuators (DEAs). The actuator was fabricated using a urethane acrylate polymer elastomer with carbon nanotube (CNT) based electrodes. The 40 mm × 20 mm rectangular actuator was powered through two electrodes at the top. It was subjected to different voltages in the range of 500 – 2500 V and the displacement of the bottom edge was observed. We report the actuator edge displacement to be 20 mm, i.e., 0.5 body lengths (BL) at static 2.5kV. The dynamic behavior of the device was also analyzed by actuating it with a square wave of various frequencies (0 to 10 Hz). We report the resonant frequency of the actuator to be 4 Hz, with a sub-harmonic at2 Hz. Few flapping structures have already been reported, wherein a soft wing is paired with a solid actuator or vice-versa, but a fully soft actuator and wing setup is a rarity. We take on this approach as it would significantly increase the appeal and power density of the structures. In addition to fabrication and mechanical characterization, the electrical response of a fully soft DEA-based flapping wing actuator was analyzed to get an overall picture of the structure which will help in further optimizations. It was subjected to static DC voltages in the range of 1 to 2 kV and the current and energy drawn by the actuator were observed. We report the average settling current varying from 7 μA to 43 μA and energy draw varying from 220 mJ to 715mJ. Further tests on a similarly fabricated actuator revealed the possibility of Time Dependent Dielectric breakdown (TDDB) encountered at 2kV after nearly 120 minutes.

July 2025