Nonlinear Dynamics of a Magnetically Coupled Dielectric Elastomer Actuator

Abstract

A magnetically coupled dielectric elastomer actuator (MCDEA) is an emerging two-degree-of-freedom DEA system that demonstrates rich dynamic behaviors and promising potential applications in robotics, energy harvesting, and smart structures. However, the three-dimensional geometry, nonlinearity, and viscoelasticity in the system lead to complex nonlinear dynamic behavior that is challenging to predict. In this work, we develop a numerical model that can accurately characterize its dynamic responses. This model, along with experimental results, demonstrates the complex dynamic phenomena of this MCDEA system, including superharmonic, primary-harmonic, and subharmonic resonances, bifurcations, and multiple modes of oscillation. Dynamic control strategies including phase tuning and frequency control are proposed in this work, allowing control of the amplitude and the appearance of a specific resonance and the occurrence of emerging dynamic behaviors, such as beat phenomena. These findings have numerous additional applications in areas including active vibrational control, energy harvesting, and programmable soft motors for on-demand locomotion.

On the Mechanical Power Output Comparisons of Cone Dielectric Elastomer Actuators

“…Here the power output performance of DCDEAs, with both membranes actuated, is investigated and benchmarked against the single-actuation counterpart for each configuration. For the DCDEA-RR, the two actuation signals are restricted to antiphase to achieve antagonistic actuation, however, due to the compliant coupling mechanism, the DCDEA-LS allows voltage signals with relative phases from 0 to 2π [23]. As a result, in this study, both antiphase and in-phase actuation voltages in the DCDEA-LS will be analyzed.…”

“…Hodgins et al [17] and Rizzello et al [18] [21] developed an electro-mechanical dynamics model for cone DEAs. Cao et al investigated the effects of actuation signal components and relative phases on the nonlinear dynamic responses of a twodegree-of-freedom (DOF) cone DEA [23]. Many dynamic vendchen@outlook.com;…”

Power optimization of a conical dielectric elastomer actuator for resonant robotic systems

“…The dynamic model is briefly described here. For detailed modelling steps please refer to our previous works[25] [26] [27].Each piece of elastomer has the initial thickness of H 0 and is pre-stretched biaxially by λ p × λ p and is constrained to the support frames. The pre-stretched membranes are then deformed out-of-plane which cause an increase in the radial stretches to λ 1_n (n = I, II for top and bottom membrane respectively) while the circumferential stretches λ 2_n remain constant (assumption (iv)).…”

Uncovering isolated resonant responses in antagonistic pure-shear dielectric elastomer actuators

“…In this work, the Gent model parameters (μ and J) are determined based on the previous studies on the silicone elastomer ELASTOSIL (Wacker Chemie AG) [42,45,46] and is given as μ = 400 kPa and J = 16. The dimension of the elastomer is defined as L 1 = 20 mm, L 2 = 200 mm, and L 3 = 0.1 mm.…”