We provide a sweep coverage algorithm for routing mobile sensors that communicate with a central data sink. This algorithm improves on its predecessors by reducing the number of unnecessary scans when different points of interest (POIs) have different requirements for the time interval within which they must be scanned (sweep period). Most sweep coverage algorithms seek to minimize the number o...

This paper presents the modeling of a four rotor vertical take-off and landing (VTOL) unmanned air vehicle known as the quad rotor aircraft. The paper presents a new model design method for the flight control of an autonomous quad rotor. The paper describes the controller architecture for the quad rotor as well. The dynamic model of the quad-rotor, which is an under actuated aircraft with fixed...

single-phase squirrel cage and three-phase induction electromotors are the most popular electromotors used in industry from long ago. when an induction motor starts with direct connection method, it takes a lot of current from the power supply (several times the nominal current); so, several methods have been devised to start such electromotors. these methods either reduce the voltage of the st...

Unbalance, fatigue crack and rotor-stator rub are the three common and important faults in a rotor-bearing system. They are originally interconnected each other, and their vibration behaviors do often show strong nonlinear and transient characteristic, especially when more than one of them coexist in the system. This article is aimed to study the vibration response of the rotor system in presen...

A 2005 TRC report presents imbalance response measurements of a hollow test rotor supported on bump-type gas foil bearings. The top speed of the tests is 25 krpm, the limit of the drive router motor. The 2005 measurements show the gas foil bearings are prone to subsynchronous whirl with amplitudes of motion exacerbated by the imbalance condition of the rotor, i.e. a forced nonlinearity. Present...

Oil-free microturbomachinery (MTM) are inevitably subjected to base or foundation excitations: passenger and commercial transportation vehicles experiencing intermittent excitation from road conditions, and (multiple) periodic load excitations from internal combustion (IC) engines in turbochargers, for example. Too large base excitations can produce severe damage, even failure, due to hard coll...

The latest development in screw compressor (helical lobed compressor) rotor profile design and rotor manufacturing machinery have prioritized basic rotor profile surface, lead and divide. However, one error that at frrst looks very basic but at the same time almost impossible to eliminate, is dealt with in this paper. The error is rotor runout.

An aeroelastic model of a smart rotor system (which incorporates blade-mounted trailing-edge flap actuators and conventional root pitch actuation) is presented in linear time invariant state space form. The servo-flap deflections are modeled as producing incremental lift and moment variations, so that any linear aerodynamic actuator can be evaluated. This smart rotor model is used to conduct pa...