Rotational Algebraic Component

Purpose

Define an algebraic constraint in terms of torque and angular speed

Library

Mechanical / Rotational / Components

Description

The Rotational Algebraic Component enforces an arbitrary algebraic constraint involving torque and angular speed.

The output signal “\(\omega\)” measures the angular speed of the marked flange with respect to the unmarked one. The output signal “\(\tau\)” measures the torque flow from the unmarked towards the marked flange. The two output signals must affect the input signal “0” by means of a direct feedthrough path. The component ensures that the input signal is zero at all times.

The direct feedthrough path defines a function \(f(\omega,\tau)\), which in turn implicitly determines the characteristic curve of the component through the constraint \(f(\omega,\tau)=0\). For instance, the choice \(f(\omega,\tau):=\tau+D \cdot \omega\) causes the Rotational Algebraic Component to act as a Rotational Damper with damping constant \(D\).

The Rotational Algebraic Component offers no direct way to specify an initial displacement. In case you need to do so, place a Rotational Damper with zero damping constant in parallel to the component and set the initial displacement property thereof.

By way of illustration, Fig. 285 shows a possible implementation of a rotational damper with variable damping constant and prescribed initial displacement.

Fig. 285 Variable rotational damper implementation example

Note

The Rotational Algebraic Component creates an algebraic loop. See Block Sorting for more information on algebraic loops.

Probe Signals

Component torque

The torque flow from the unmarked towards the marked flange.

Component speed

The angular speed of the marked flange with respect to the unmarked one.

Component power

The power consumed by the component.