In an electro-mechanical valve actuated engine, solenoid actuators drive the valves that control airflow into the cylinders, allowing elimination of the camshaft and flexible control of the valve timing. Individual control of the valves provides flexibility in valve timing over all engine operating conditions and fully enables the benefits of variable valve timing. This paper describes a closed...

In this paper, the method of modern control approach for the design of controller and observer is used. Other functions such as neural controllers - or fuzzy sliding mode control can be found in this work and the results are compared. First, a dynamic model of the servo valve is intended for the governing equations in state-space form expression are obtained. Due to the system integrator is exp...

An automated, pre-programmed, multiplexed hydraulic valve actuator is described. The valve is membrane-based and normally open. In contrast to the membrane-based pneumatic valve, the hydraulic valve uses hydraulic liquid to exert the control pressure. The line pressure is controlled with a roller moving over a prefabricated topology. Multiple rollers, each traversing its own track, are assemble...

As the control valve of the propulsion system engine, the electromagnetic valve play an important role in attitude and orbit control for spacecraft. While the leak of the electromagnetic valve has always been the main cause of the failure of the propulsion system. Due to the shell’s complex structure as well as many seam weld on it, the normal NDT is unfit to check out some small cracks and mic...

We have designed and fabricated the first single-wafer proportional micro control valve with built-in capacitive displacement sensing. The displacement sensor can facilitate high-speed active proportional control of gas flow through the valve. This is an essential requirement for non-invasive blood pressure waveform monitoring based on following the arterial pressure with a counter pressure. We...

quadricuspid aortic valve (qav) is an uncommon congenital anomaly which was an incidental finding during surgery or autopsy in the past. we present the case of a 44-year-old woman with moderately severe aortic regurgitation due to unequal cusp size qav diagnosed via transesophageal echocardiography. due to echocardiographic imaging improvement, the diagnosis of qav is now easier and earlier tha...