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                    Artificial Muscles Using EAP                                                 279
























                    Figure 10.8  Evaluation of the EAP-based braille display device for the visually impaired. (Courtesy of Hyoukryeol
                    Choi, Sungkyunkwan University, Suwon, Kyunggi-do, Korea.)



                    10.5.2 EAP-Actuated Biomimetic Robots

                    With current technology, the appearance and behavior of biological creatures are animated in
                    various simulation studies, computer generated imagery (CGI), and commercial movies (Blum-
                    berg, 2003). However, in past years, engineering such biomimetic intelligent creatures as realistic
                    robots was a significant challenge due to the physical and technological constraints and the
                    shortcomings of available technology. Making robots that can hop and land safely without risking
                    damage to the mechanism, receive pushes while staying stable or make body and facial expressions
                    of joy and excitement — which are very natural for humans and animals — are extremely complex
                    to engineer. The use of AI, effective artificial muscles, and other biomimetic technologies is
                    expected to make the possibility of realistically looking and behaving robots into practical engin-
                    eering models (Bar-Cohen and Breazeal, 2003). Mimicking nature would immensely expand the
                    collection and functionality of the robots allowing performance of tasks that are impossible with
                    existing capabilities.
                      The field of artificial muscles offers many important capabilities for the engineering of robots
                    that are inspired by biological models and systems. The capability to produce EAP in various
                    shapes and configurations can be exploited using such methods as stereolithography and ink-jet
                    processing techniques. Potentially, a polymer can be dissolved in a volatile solvent and ejected
                    drop-by-drop onto various substrates. Such rapid prototyping processing methods may lead to
                    mass-produced robots in full 3D details including the actuators allowing rapid prototyping and
                    quick transition from concept to full production (Bar-Cohen et al., 2004).
                      Using EAP actuators, biologically inspired robots may be developed with capabilities that are far
                    superior to natural creatures since they are not constrained by evolution and survival needs. Examples
                    may include artificial bugs that walk, swim, hop, crawl, and dig while reconfiguring themselves as
                    needed. An important addition to this capability can be the application of telepresence combined with
                    virtual reality using haptic interfacing. While such capabilities are expected to significantly change
                    future robots, additional effort is needed to develop robust and effective polymer-based actuators.
                    Potential actuators may include the dielectric elastomer or the ferroelectric EAP.
                      To promote the development of effective EAP actuators in support of future development of
                    such future biomimetic robots, toys, and animatronics, two testbed platforms were developed (see
                    Figure 10.9). These platforms are available at the author’s JPL’s NDEAA lab and they include an
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