Passive systems have the beneficial property that their interconnections with other passive systems result in necessarily stable systems. This vmue of passive systems can be exploited with hydraulic systems to build owerful machines that are safe and human friendly. A digculty in a plying the passivity concept to electrohydraulic systems is i a t they are not intnnsically passive. In a previous...

The paper deals with the problems of kinematic and dynamic modelling, simulation and experimental test of the planar two-link manipulator with the electrohydraulic control. The kinematic model was constructed on the basis of the kinematic relations and the dynamic model by means of bond graphs. On the test stand the dynamic characterisation and identification of the model mechanism was carried ...

A practical approach to design a feedforward-plus-proportional-integral-derivative (FPID) controller for accurate and smooth velocity control on a hydraulic linear actuator is presented. The integrated controller consists of a feedforward loop and a PID loop. The feedforward loop is designed to compensate for the nonlinearity of the electrohydraulic system, including the deadband of the system ...

Electrohydraulic and extracorporeal shock waves were used to treat the colorectal and gastric cancer cell lines LIM 2412 and MKN45. The effect on viability, cell proliferation, and the action of antitumour drugs was studied. Results showed that electrohydraulic and extracorporeal shock waves were cytotoxic to all cell lines and also caused considerable inhibition of cell proliferation. A signif...

The study of the invariant error dynamics controller for a six-degrees-of-freedom (dof) electrohydraulic Stewart platform is presented. Rigid body and electrohydraulic models, including servovalve dynamics are employed. Friction is also included in the mechanical model. The developed controller employs the dynamic and hydraulic model of the system and yields the six servovalve input current vec...

Ninety percent of patients with intraductal biliary stones are successfully treated with sphincterotomy and subsequent stone extraction. However, technical difficulty increases with stone size and giant stones require fragmenation to facilitate endoscopic removal. For stones too large to be engaged in a basket for mechanical lithotripsy laser and electrohydraulic lithotripsy have been proposed ...

This paper deals with the achievement of a reduced order mathematical model using the singular perturbations method for an electrohydraulic system composed by a hydraulic cylinder which is controlled with an electrohydraulic servovalve with five ways. Due to the high value of the bulk-modulus of fluid, to the low value of the fluid occupied volume and also to the spool valve mass low, the equat...