Real-time control of dielectric elastomer actuators via bioelectric and biomechanical signals

Dielectric elastomers (DEs) represent a highly-performing class of electromechanically active polymers, largely studied nowadays to develop soft actuators with pseudo-muscular functions, suitable for a broad spectrum of biomedical and biorobotic applications. As such, they are investigated to achieve the ambitious goal of developing artificial muscles. In the perspective of using this technology for systems interfacing men and machines, the possibility to control them in real time via human bioelectric and biomechanical signals is a fundamental requirement. This work provides the first detailed investigation on this topic. The amplitude and frequency of actuation of buckling DE actuators were dynamically controlled with electromyographic, electrocardiografic and respitrace signals, subjected to low-pass filtering and amplification. The actuators were able to follow, in real time and in synchrony, inputs corresponding to skeletal muscle contraction, heart beating and respiratory activity. This work shows that real-time open-loop control of DE actuators via human bioelectric and biomechanical signals is feasible and readily achievable.