The EHA (electro hydraulic actuator) has a notable advantage over conventional actuators as it uses closed-loop circuit, reducing the size and volume of oil, eliminates pressure losses caused by valve orifices. However, accurate control performance is difficult to achieve using traditional PID (proportional integral derivative) controller due strongly nonlinear, time-varying, unknown dynamics s...

An endeavor was conducted to explore the design and development of a two-axis linear reluctance actuator for use as a part of a nano-positioner with the application of serving as a small scale kinematic coupling assembly station. This nano-positioner is designed to be able to accurately and repeatable provide precise motion control of small objects with a resolution on the nanometer scale. This...

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...

Many existing control allocation methods separate the high-level design from their low-level design, assuming that constraints of actuators can be guaranteed by allocator. This idea may not suitable for nonlinear fixed-wing unmanned aerial vehicle studied here, which hence motivates this work. In paper, we propose a new dual-layer optimization-based method, in proposed allocator, on one hand, m...

Wind-tunnel experimentswere conducted on a 47-deg sweep, scaled 1303unmanned air vehiclemodel to assess the performance of an innovative windward-surface plasma actuator design for flight control at low angles of attack. Control was implemented by altering the flow past an aft separation ramp on the windward side using a single dielectric barrier discharge plasma actuator. The influence of ramp...

This paper reports on the development of a comprehensive nonlinear mathematical model of a novel inherently compliant fluidic actuator with Rotary Elastic Chambers (REC–actuator). The actuator is intended for robotic devices working in direct physical contact with humans and can be operated by both, liquid as well as gaseous working fluid. In the hydraulic realization the REC-actuator is contro...

This paper proposes a magnetic actuator system of a new type capable of inspection in a complex pipe by means of a new motion principle. Using plural vibration components, the magnetic actuator is able to move in the complex pipe. A magnetic actuator of the reversible type, due to opening and closing of a compound material by using elongation and contraction of four shape-memory-alloy (SMA) coi...

In this research, a functionally graded microbeam bonded with piezoelectric layers is analyzed under electric force. Static and dynamic instability due to the electric actuation is studied because of its importance in micro electro mechanical systems, especially in micro switches. In order to prevent pull-in instability, two piezoelectric layers are used as sensor and actuator. A current amplif...

the subject under investigation has been electronic learning (e-learning) or electronic education (e-education), specifically concentrating on virtual university. virtual university has been the subject of much debate in recent years. in short, the concept of virtual university denotes a learning/educational system/environment based on internet where higher education is promoted using tools and...

In this study, we succeeded in manufacturing a novel nanofiber hydrogel actuator that caused a bending and stretching motion synchronized with external pH oscillation, based on a bromate/sulfite/ferrocyanide reaction. The novel nanofiber gel actuator was composed of electrospun nanofibers synthesized by copolymerizing acrylic acid and hydrophobic butyl methacrylate as a solubility control site....