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...

: 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...

Government regulations to address technological risks are important for the successful development and application of nanotechnology, but there is an ongoing debate in the USA about who is responsible for the regulation of nanotechnology. In a mail survey of leading US nano-scientists, we examine scientists’ perceptions about nano-regulation, including the government level (local, national, or ...

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 ...

For elderly and physically disabled people, support systems that assist their active daily life are as important as appropriate rehabilitation. We have designed a rotational meshing actuator for a life support system based on a mobile robot. The present paper explains the basic concept of the actuator and its design details. The actuator comprises a motor-controlled active mechanism mated with ...

Piezoelectric bimorph actuation has been successfully used in numerous types of microdevices, most notably micropumps. However, even for the simple case of circular geometry, analytical treatments are severely limited. This study utilized the finite-element method to optimize the deflection of a circular bimorph consisting of a single piezoelectric actuator, bonding material and elastic plate o...

The latency time, which is the residual vibration of afine actuator and track eccentricity, has been the aim for direct pull-in in optical disk system. Modified velocity profiles of the coarse actuator and control inputs of the fine actuator have been proposed for the minimum residual vibration. Generally, there exists eccentricity due to mismatch of the disk center and the axis of a spindle mo...

We consider initial and boundary value problems modelling the vibrations of a plate with piezoelectric actuator. The simplest model leads to the Bernoulli-Euler plate equation with right hand side given by a distribution concentrated in an interior curve multiplied by a real valued time function representing the voltage applied to the actuator. We prove that, generically with respect to the cur...

Series elastic actuators have a spring intentionally placed at the actuator output. Measuring the spring strain gives an accurate measurement for closed-loop actuator force control. The low spring stiffness allows for high control gain while maintaining actuator stability. This gives series elastic actuators many desirable properties including high bandwidth at moderate force amplitudes, low ou...