We study the mechanical properties of fin rays, which are a fundamental component of fish fin structure. We derive a linear elasticity model that predicts the shape of fin rays, given the input muscle actuation and external loading. We then test the model using experiments that measure (i) the ray deflection for a given actuation at the muscular interface, and (ii) the force-displacement respon...

We provide necessary and sufficient conditions for Lyapunov stabilizability and exponential stabilizability by the energy shaping method for the class of all linear controlled Lagrangian systems of an arbitrary degree of under-actuation, and for the class of all controlled Lagrangian systems of one degree of under-actuation. We give a sufficient condition for asymptotic stabilizability for the ...

In this paper, the stability of a functionally graded magneto-electro-elastic (FG-MEE) micro-beam under actuation of electrostatic pressure is studied. For this purpose Euler-Bernoulli beam theory and constitutive relations for magneto-electro-elastic (MEE) materials have been used. We have supposed that material properties vary exponentially along the thickness direction of the micro-beam. Gov...

In this paper the actuation system, often encountered high-precision motion systems, is studied. To find out the limitations of the actuation system, a integrated electromechanical model of the amplifier, actuator and mechanics is derived. This is done in a system’s theory-approach, so that amplifier feedback circuit design can be tuned using loop-shaping techniques. Stability analysis is carri...

Actuator materials can directly convert different types of energy into mechanical energy. In this work, we designed and fabricated electrothermal air pump-type actuators by utilization of various nanostructured carbon materials, including single wall carbon nanotubes (SWCNTs), reduced graphene oxide (r-GO), and graphene oxide (GO)/SWCNT hybrid films as heating elements to transfer electrical st...

Localization of magnetically actuated medical robots is essential for accurate actuation, closed loop control and delivery functionality. Despite extensive progress in the use magnetic field inertial measurements pose estimation, these have been either under single external permanent magnet actuation or coil systems. With advent new systems comprised multiple magnets increased manipulability, l...

The study investigates the effects of servo valve nonlinearity, actuation compliance and friction related nonlinearity on the dynamics of a flight control surface, during its deployment through an electro-hydraulic actuation system. Starting from the pilot command, a realistic model of the electro-hydraulic actuation system is evolved, which includes the command lags, servo valve nonlinearity, ...

Recent advances in fabricating controlled-morphology vertically aligned carbon nanotubes (VA-CNTs) with ultrahigh volume fraction create unique opportunities for markedly improving the electromechanical performance of ionic polymer conductor network composite (IPCNC) actuators. Continuous paths through inter-VA-CNT channels allow fast ion transport, and high electrical conduction of the aligned...

Smart actuators have many potential applications in various areas, so the development of novel actuation materials, with facile fabricating methods and excellent performances, are still urgent needs. In this work, a novel electromechanical bimorph actuator constituted by a graphene layer and a PVDF layer, is fabricated through a simple yet versatile solution approach. The bimorph actuator can d...