Tubular actuator using dielectric elastomers and conductive fabric for orthotic applications

Leg orthotic devices are often used to support and help rehabilitate individuals who have lost some functionality in their leg muscles, such as seniors, veterans, or other individuals who have been injured or who suffer from diseases like myopathy. Dielectric elastomer actuators (DEAs) are soft actuation materials with promising applications in robotics and biomedical devices because they are compact, lightweight, and resilient. In this paper, a tubular actuator is developed using DEAs and conductive fabric, and it is tested for orthotic applications. The novel orthotic technology developed in this paper has potential to provide the same support and rehabilitation to muscles as traditional leg braces, while being lighter/less bulky, more comfortable due to the use of conductive fabric, and able to adjust its size as one’s limb grows by using DEA. A prototype of this device is developed and characterized. A DEA was actuated on a foot-like mechanism by a periodic signal while the extent of the movement was observed. The experimental results validated the capability of DEAs to actuate a foot-like mechanism, which encourages future development of a dielectric elastomer-based orthotic leg brace.