The time delay of variable valve actuators has a significant influence on engine lift tracking performance. For camless hydraulic actuators, response is affected by many factors, such as friction and control response. In this paper, investigated in depth. Experiment results show that motion can be divided into open close delay. They are different even the same cycle. Complicated characteristics...

Nowadays, the constant striving to reduce emission and increase overall efficiency over a wide range of speeds loads internal combustion engine (CE) is observed. The different methods for improving charge exchange in engine, particularly ones based on variable valve timing are sought. This variability can be achieved, among others by using electrohydraulic drive. goal present study compare dyna...

This paper deals with a hybrid actuator composed by a piezo part and a hydraulic one and with a cascade PID-PID control structure for camless engine motor applications. The idea is to use the advantages of both, the high precision of the piezo part and the force of the hydraulic one. In fact, piezoelectric actuators (PEAs) are commonly used for precision positionings, despite PEAs present nonli...

A study has been carried out to investigate the influence of soot contaminated automotive lubricants in the wear process of a simulated engine valve train contact. Previous research on this topic has been mainly performed from a chemical point of view in fundamental studies, with insufficient relevance to real engine conditions i.e. load and geometry. This study investigates the conditions unde...

This paper addresses the tracking of near periodic time varying signals by proposing an integrated approach for simultaneously designing previewed feedforward, feedback, and repetitive control in a unified framework. The design problem is formulated as a μ-synthesis problem, in which the distance between a specified reference model and the achievable tracking performance with feedforward compen...