Electroactive Artificial Muscles Based on Functionally Antagonistic Core–Shell Polymer Electrolyte Derived from PS-b-PSS Block Copolymer

Electroactive ionic soft actuators, a type of artificial muscles containing a polymer electrolyte membrane sandwiched between two electrodes, have been intensively investigated owing to their potential applications to bioinspired soft robotics, wearable electronics, and active biomedical devices. However, the design and synthesis of an efficient polymer electrolyte suitable for ion migration have been major challenges in developing high-performance ionic soft actuators. Herein, a highly bendable ionic soft actuator based on an unprecedented block copolymer is reported, i.e., polystyrene-b-poly(1-ethyl-3-methylimidazolium-4-styrenesulfonate) (PS-b-PSS-EMIm), with a functionally antagonistic core–shell architecture that is specifically designed as an ionic exchangeable polymer electrolyte. The corresponding actuator shows exceptionally good actuation performance, with a high displacement of 8.22 mm at an ultralow voltage of 0.5 V, a fast rise time of 5 s, and excellent durability over 14 000 cycles. It is envisaged that the development of this high-performance ionic soft actuator could contribute to the progress toward the realization of the aforementioned applications. Furthermore, the procedure described herein can also be applied for developing novel polymer electrolytes related to solid-state lithium batteries and fuel cells

Torsional vibration analysis of shafts based on Adomian decomposition method

In this paper free torsional vibration of shafts is studi ed using a new approach of solving differential equations called Adomian decomposition method (ADM). Applying this method to free torsional vibration of shafts means a systematic and straightforward procedure for calculating both low and high frequency modes. In this paper different boundary conditions are app lied to both end of the shaft and firs t five natural frequencies and mode shapes are calculated for four different cases. Obtained results are compared with results presented in literature. These results demonstrate that ADM is a suitable approach for analysis of free torsional vibration of shafts which provides precise results with high order of accuracy