A continuously-stable linear actuation based on bending type artificial muscles

Electroactive polymer actuators, also known as artificial muscles, can operate both in wet and dry media under as small as 1 Volt potential difference. This paper reports on a multi-stable linear actuation mechanism articulated with artificial muscles. Kinematic and finite element analyses of the mechanism are studied to demonstrate the feasibility of the mechanism. Experiments were conducted on a real mechanism articulated with a multiple number (4 or 8) of electroactive polymer actuators, which had the dimensions of 12×2×0.17mm. The numerical and experimental results demonstrate that the angular displacement of the artificial muscles is accurately transformed into a rectilinear motion by the proposed mechanism. This study suggests that this multi-stable linear actuation mechanism can be used as a programmable switch and/or a pump in MEMS by adjusting the input voltage and scaling down the mechanism further.