In control of vibrations, diffusion and many other problems governed by partial differential equations, there is freedom in the choice of actuator location. The actuator location should be chosen to optimize performance objectives. In this paper, we consider H∞ performance with state-feedback. It is shown that the corresponding optimal actuator problem is wellposed. In practice, approximations ...

the natural frequency and pull-in instability of clamped-clamped nano-actuators in the presence of a dielectric layer are analyzed. the influence of the presence of casimir force, electrostatic force, fringing field effect, axial force, stretching effects and the size effect are taken into account. the governing equation of the dynamic response of the actuator is transformed in a non-dimensiona...

Indirect control of qubits by a quantum actuator has been proposed as an appealing strategy to manipulate qubits that couple only weakly to external fields. While universal quantum control can be easily achieved when the actuator-qubit coupling is anisotropic, the efficiency of this approach is less clear. Here we analyze the time efficiency of quantum actuator control. We describe a strategy t...

A new membrane actuator based on our previous diaphragm actuator was designed and constructed to improve the dynamic performance. The finite element analysis was used to estimate the frequency response of the composite membrane which will be driven close to its resonance to obtain a large stroke. The membrane is made of ferromagnetic shape memory alloy (FSMA) composite including a ferromagnetic...

Design, modeling, and measurements are discussed for a new direct-drive, electromagnetic valve actuator (EVA) for internal combustion engines. The actuator offers greater dynamic performance than previous designs and achieves fully flexible valve timing and lift, which provides great benefits in engine performance including increased engine efficiency, reduced emissions, and improved low-end pe...

The traditional optical pickup actuator model based on the assumption that the actuator spatial magnetic field distributes uniformly ignores the crosstalk characteristic among the movements of different directions. Crosstalk characteristic is a key factor that affects the actuator dynamic property and, consequently, the accuracy of reading and writing operation in the future higher density opti...

purpose: to report a case who had optic disc duplication, a rare congenital disorder characterized by two well-defined discs in one eye. case report: a 19 months-old child presented with unilateral epiphora in the right eye since birthday. the right eye was smaller than the left eye and mild ptosis was apparent. nasolacrimal duct probing was performed under general anesthesia. the examination r...

: investigating the mechanical behaviour of a healthy human ankle shows that it can be simulated by a mechanism composed of simple elements such as spring, and actuator. hence, appropriate design of this mechanism can be resulted to an artificial ankle that can help amputees properly. researches show that whatever the biomechanical behaviour of artificial ankle is similar to that of natural ank...

The non-return mechanism is the key device that plays role of braking in opening-and-closing electric actuator an amphibious aircraft hatch door. ball-and-socket contact pair, providing pressing force, and multi-disc friction supplying torque, are two core components mechanism. In this paper, dynamic model established considering freedom rotation-translation. Based on MATLAB/Simulink, solution ...

In this work, an active vibration control method using compliant-based actuators is proposed for controlling a wide range of vibration and its noise-associated applications. The compliant-based actuator combines a conventional actuator with elastic elements, such as passive springs, that can be demonstrated to have better accuracy and robustness for force control compared to conventional stiff ...