The input to an electro-hydraulic (EH) servovalve is typically a current or a differential current that powers an electromagnetic torque motor. The differential current Δi is typically supplied by an amplifier to avoid excess loading of the interface to the computer or controller. In the simplest (but not typical) form, the torque motor moves a spool valve as shown below. The spool valve allows...

A flexible microactuator (FMA) driven by an electro-pneumatic (or electro-hydraulic) system has been developed. The FMA has three degrees of freedom: pitch, yaw, and stretch; and these are suitable movements for miniature robotic mechanisms such as fingers, arms or legs. The construction is of fiber-reinforced rubber and the mechanism is very simple. Gentle miniature robots with no conventional...

This thesis presents research work related to the impedance control of redundant manipulators. The main goal is to study the effects of redundancy on the dynamic behaviour of manipulators. Firstly, theoretical developments related to redundancy, dynamics and impedance control are presented in general form without restriction to any particular manipulator. The purpose is to keep the findings use...

Lower cost, higher control performance and significantly less energy consumption are the goals for the design of any industrial systems including electro-hydraulics. The paper presents an integrated mechatronic design approach – seamless integration of advanced control techniques with novel hardware reconfiguration/re-design – as one of the tools to achieve these lofty goals simultaneously. The...

Linear electro hydraulic servo-drives have been built and used in various industrial equipment for more than sixty years. They are distinguished by the ability to develope extremely large forces with the positioning accuracy of the order of a micrometer, ensuring, at the same time, very good dynamic features. The drives characterised by very slow motion and large force are used, among others, i...

In this study, a nonlinear sliding-mode controller is designed for force tracking of a piezoelectric-hydraulic pump (PHP)-based actuation system, which is developed to replace the current electro-hydraulic actuation systems for automatic transmission (AT) friction elements, such as band brakes or clutches. By utilizing the PHP, one can eliminate the various hydraulic components (oil pump, regul...