This study evaluates a technique for the closed-loop position and velocity control of a wire scanner actuator. The focus of this technique is to drive a stepper motordriven actuator through a 1-mm move using a combination of velocity feedback control and position feedback control. More specifically, the velocity feedback control will be utilized to provide a smooth motion as the controller driv...

One of the research goals in robotics is the development of home-help robots. The development of a control approach for a novel lightweight and multifunctional shape memory alloy (SMA) actuator scalable in force and length for robots is presented in this paper. The SMA actuator is based on lightweight bundles of thin wires of prestrainend shape memory alloy that change their length when heated ...

We present a hydro-elastic actuator that has a linear spring intentionally placed in series between the hydraulic piston and actuator output. The spring strain is measured to get an accurate estimate of force. This measurement alone is used in PI feedback to control the force in the actuator. The spring allows for high force fidelity, good force control, minimum impedance, and large dynamic ran...

An actuator is a device that converts input energy into mechanical energy. According to various types of input energy, various actuators have been advanced. Displacement in the electromagnetic, hydraulic and pneumatic actuators achieve by moving a piston via electromagnetic force or pressure, however the piezoelectric actuator (piezoceramic plates) displace directly. Therefore, accuracy and spe...

Installing a turbine in duct generally increases the flow through rotor. If there is confinement due to limited water depth, presence of lateral boundaries, or adjacent turbines, further enhancement rotor will be achieved. Extensive studies ducted turbines uni-directional have shown that rotor-based power coefficientCpcan exceed Betz-Joukowsky limit (BJL) for bare turbine, whereas exceedance BJ...

Wind farm flow control aims to improve wind turbine performance by reducing aerodynamic wake interaction between turbines. Dynamic, physics-based models of flows have been essential for exploring strategies such as redirection and dynamic induction control. Free-vortex methods can provide a computationally efficient way model dynamics optimisation. We present control-oriented free-vortex 2D 3D ...

This thesis presents a new actuator system consisting of a micro-actuator and a macroactuator coupled in parallel via a compliant transmission. The system is called the Parallel Coupled Micro-Macro Actuator, or PaCMMA. In this system, the micro-actuator is capable of high bandwidth force control due to its low mass and direct-drive connection to the output shaft. The compliant transmission of t...

Monkeys can learn to directly control the movements of an artificial actuator by using a brain-machine interface (BMI) driven by the activity of a sample of cortical neurons. Eventually, they can do so without moving their limbs. Neuronal adaptations underlying the transition from control of the limb to control of the actuator are poorly understood. Here, we show that rapid modifications in neu...