phase lag

Phase lag is a property of all rotating systems acted upon by a periodic force.

In addition, sensory feedback from the environment may contribute to resultant phase lag.

Conversely, the right-handed transmission lines are a low-pass filter with phase lag.

In purely viscous materials, strain lags stress by a 90 degree phase lag.

For a purely viscous fluid, there will be a 90 degree phase lag of strain with respect to stress.

Phase lag is a separate phenomenon from gyroscopic precession, which applies only to rigid systems.

In modern helicopters, the input is mechanically translated 90 degrees to compensate for phase lag and to render such turns more intuitive.

In federal mapping and names collection efforts, there is often a phase lag where a delay occurs in adoption of a locally-used name.

The lag compensator provides phase lag at low frequencies which reduces the steady state error.

Let be the phase lag:

The resulting phase lag in voltage is identical for both energy storage mechanisms, making them indistinguishable in a normal circuit.

The phase lag depends on the frequency of change of the input, and goes to zero as the frequency decreases.

For systems hinged at the axis of rotation ( in our case, a semi rigid flapping type rotor head) the phase lag is 90 degrees.

Viscoelastic polymers have the characteristics in between where some phase lag will occur during DMA tests.

Phase lag should not be confused with the much smaller lead-lag of a blade due to angular momentum conservation as a blade flaps.

Doctorates in science peaked somewhere around the time of Apollo 11, maybe even with the proper phase lag after the start of the Apollo program.

Rich notes, His skillful use of gradual phase lag has led to some of his major achievements, bringing great beauty and expressiveness to his music.

For systems that are hinged at some distance from the axis of rotation (such as a fully articulated rotor head) the phase lag is less than 90 degrees.

Viscoelastic materials exhibit behavior somewhere in between that of purely viscous and purely elastic materials, exhibiting some phase lag in strain.

Phase lag (rotorcraft) will cause the extra lift to be seen approximately 90 degrees later in rotor rotation in semi-rigid two bladed rotor systems.

As a consequence of the phase lag, to turn the rotorcraft to the left or right would theoretically require a forward or backward cyclic if there was no mechanical correction.

In practice this wouldn't work because the detectors would need impossibly precise information about the speed of eye movements and the phase lag between the central movement commands and the actual movement of the image.

However due to the reactance caused by the length difference, the phase lag of the current in the reflector, added to this 180 lag, results in a phase advance, and vice versa for the director.

Typically the open-loop phase lag (relative to input) varies with frequency, progressively increasing to exceed 180 , at which frequency the output signal becomes inverted, or antiphase in relation to the input.

In the aerodynamics of rotorcraft such as helicopters, phase lag refers to the difference in phase between the position of greatest rotational speed of a rotor blade and the position of its greatest upward flap.