Valve switching is one of the most important power losses in digital hydraulics. In this paper, a dynamic Zero-Flowrate-Switching (ZFS) control method developed for hydraulic/pneumatic systems. The proposed strategy to actively reduce flowrate passing through valve zero before off valve. To realize it, an accessory line, which RLC oscillator applied generate sinusoidal flowrate, allocated paral...

The suitability of artiicial neural networks (ANNs) for detecting fault conditions in pneumatic control valve actuators is investigated. Speciically, the ability of a neural network to act as a predictor of correct valve behaviour is examined. Experimental results indicate that standard network architectures are unsuitable for temporal prediction of non-linear system behaviour. An original recu...

The dynamic characteristic of pneumatic brake system is very important, so the full-parameter model of the pneumatic brake system was established on the base of the technology of computer simulation. Its key brake components include brake valve, relay valve, diaphragm brake chamber and pneumatic circuit. AMESim was first introduced on the basis of mathematical derivation. So the multivariable c...

A group lubrication system of mechanical components for a walking excavator is proposed, the original design lubricator with pneumatic drive and controlled electro-magnetic valve developed

This work describes a simple and inexpensive approach for controlling the pneumatic valves that were invented in Quake's group to miniaturize the whole system for portable and disposable microfluidic devices. The valves are assembled from two parts. One is the polydimethylsiloxane (PDMS) channels formed by multilayer soft lithography. The other is a polymethylmethacrylate (PMMA) frame with mach...

In this paper, a procedure for quantifying valve stiction in control loops based on ant colony optimization has been proposed. Pneumatic control valves are widely used in the process industry. The control valve contains non-linearities such as stiction, backlash, and deadband that in turn cause oscillations in the process output. Stiction is one of the long-standing problems and it is the most ...

In response to the problems of inaccurate pneumatic control valve model, slow position control, and low precision in industrial process, some improvement methods are proposed. Firstly, fractional-order concept is introduced based on first-order inertia model IBBO (improved biogeography-based optimization) used for iteration obtain a specific transfer function model. Secondly, two-degree-of-free...

This work describes a method for the simulation of multiple pneumatic actuators in a context of multi body mechanical systems. The model of the single actuator is based on elliptical approximation of non-linear pneumatic devices; friction and sticking phenomena are considered as well. Pneumatic devices introduce forces and new state variables into the complete multibody system: we developed a s...

Pneumatic servo actuators are characterized by highly nonlinear dynamics from spool valve command to cylinder pressure, and as such are well suited to the use of nonlinear control methods requiring measurement of the full state, such as sliding mode control. This paper investigates the possibility of eliminating the pressure measurement required for nonlinear control in lieu of a nonlinear pres...

The control of humanoid robot hands has historically been expensive due to the cost of precision actuators. This paper presents the design and implementation of a low-cost air muscle actuated humanoid hand developed at Curtin University of Technology. This hand offers 10 individually controllable degrees of freedom ranging from the elbow to the fingers, with overall control handled through a co...