Wireless actuation and control of ionic polymer–metal composite actuator using a microwave link

Abstract

The ionic polymer-metal composite (IPMC), a type of electroactive polymer (EAP) actuator, has created a unique opportunity to design robots that mimic the motion of biological systems due to its soft structure and operation at a low voltage. Although this polymer actuator has strong potential for a next-generation artificial muscle actuator, it has been observed by many researchers that supplying actuation voltages in multiple locations is challenging. In robotic applications, a tethered operation is prohibited and the battery weight can be critical for actual implementation. In this research, the remote unit can provide necessary power and control signals to the target mobile robot units actuated by IPMCs. This research addresses a novel approach of using a wireless power link between the IPMC and a remote unit using microstrip patch antennas designed on the electrode surface of the IPMC for transmitting the power. Frequency modulation of the microwave is proposed to selectively actuate a particular portion of the IPMC where the matching patch antenna pattern is located. This approach can be especially useful for long-term operation of small-scale locomotion units and avoids problems caused by complex internal wiring often observed in various types of biologically inspired robots.Keywords: ionic polymer-metal composite actuator; microwave link; wireless actuation; robotic application; biomimetic robot IntroductionRecent advances in artificial muscle actuators based on electroactive polymers (EAPs) have created a unique opportunity to accommodate greater flexibility and more degrees of freedom to design biologically-inspired robots. The unique properties of biological muscle are large strain, moderate stress, fast speed, good efficiency and long cycle life. A new technology based on polymer science and engineering has enabled EAP to simulate these properties and functions. An ionic polymer-metal composite (IPMC) has demonstrated many new capabilities in robotic actuation technology due to its low-voltage requirement, relatively large deformation and shape-changing capabilities. In particular, the IPMC can be fabricated in various shapes and sizes; with proper intelligent and biomimetic shape-changing control schemes, such as polymeric actuators, the IPMC can offer clear advantages in developing an intelligent biomimetic robotic system over the traditional electromechanical actuators.

Hydrodynamic performance of a biomimetic robotic swimmer actuated by ionic polymer–metal composite

“…Kim proposed an analytical model of single-or multi-segment IPMC actuators that operate in water [10]. Recently, the wireless actuation and control of IPMC actuators were also investigated [11,12]. Our previous work proposed an efficiency model of a robotic fish, where the total power consumption of the IPMC was considered in the model [13,14].…”