Electric variable speed drives (VSDs) based on two VSDs connected to a multiphase machine are an attractive solution replace high-power mechanic and hydraulic systems in many sectors of industry transportation because they present high performance with reduced cost, volume weight. Among the causes which affect reliability dual VSDs, common-mode current flowing through bearing is important issue...

The fundamental objective in developing variable stiffness actuators is to enable the actuator to deliberately tune its stiffness. This is done through controlling the energy flow extracted from internal power units, i.e., the motors of a variable stiffness actuator (VSA). However, the stiffness may also be unintentionally affected by the external environment, over which, there is no control. T...

In this paper, an extension of the so-called Intrinsic Passive Control (IPC) is illustrated, showing that an improvement of performances can be achieved by considering different types of energy-storing elements, i.e. “springs”, in the IPC. In particular, two new “springs” are introduced: a ‘variable rest length’ spring and a ‘variable stiffness’ spring, that are properly defined in order to mai...

A 2-year-old boy was admitted for a 16-day history of intermittent fever (up to 40.5°C) with no other symptom. He had been followed since birth for a large midmuscular ventricular septal defect with a left-to-right shunt and signs of congestive heart failure. At 2 months of age, the patient had a pulmonary artery banding, and at 16 months of age he underwent hybrid periventricular closure of a ...

Analysis of variation in tooth size in a population of red fox, Vulpes vulpes (Linnaeus, 1758) from Poland based on three indices (coefficient of variation CV, variation index VSD, residual standard deviation RSD) and its correlation with average tooth size revealed two contradictory patterns. The CV and VSD were significantly correlated with average tooth sizes, while RSD values was independen...

A NURBS-based isogeometric finite element formulation is developed and adopted to the free vibration analysis of finite square and skew laminated plates. Variable stiffness plies are assumed due to implementation of curvilinear fiberreinforcements. It is assumed due to employment of tow placement technology, in each ply of variable stiffness composite laminated plate the fiber reinforceme...

Recent developments in the area of smart structures indicate that variable geometry / stiffness truss network is of fundamental importance in designing smart transformable structures and systems for space applications. This paper presents the conceptual design and dynamic modeling of a cooperative re-configurabel dual-arm robotic structure called Dual-Arm Cam-Lock Manipulator. The Manipulator i...

Slow and accurate finger and limb movements are essential to daily activities, but the underlying mechanics is relatively unexplored. Here, we develop a mathematical framework to examine slow movements of tendon-driven limbs that are produced by modulating the tendons’ stiffness parameters. Slow limb movements are driftless in the sense that movement stops when actuations stop. We demonstrate, ...

In the present paper, a fuzzy controller applied to a Variable-Speed Drive (VSD) for use in Photovoltaic Pumping Systems (PVPS) is proposed. The fuzzy logic system (FLS) used is embedded in a microcontroller and corresponds to a proportional-derivative controller. A Light-Dependent Resistor (LDR) is used to measure, approximately, the irradiance incident on the PV array. Experimental tests are ...

Vacuum sealing drainage (VSD) is an effective technique used to promote wound healing. However, recent studies have shown that it exerts positive pressure (PP) rather than negative pressure (NP) on skin. In this study, we created a homemade device that could maintain NP on the wound, and compared the therapeutic effects of VSD-induced PP to those of our homemade device which induced NP on wound...