Inertia

Purpose

Model a rotating body with inertia

Library

Mechanical / Rotational / Components

Description

../../_images/inertia.svg

This component models a rotating body with inertia and two rigidly connected flanges. The angular speed is determined by the equation

\[\frac{d}{dt}\omega = \frac{1}{J}\cdot(\tau_1 + \tau_2)\]

where \(\tau_1\) and \(\tau_2\) are the torques acting at the two flanges towards the body.

Parameters

Moment of inertia

The moment of inertia \(J\), in \(\left( \frac{\mathrm{kg}\cdot\mathrm{m^2}}{\mathrm{rad^2}} \right)\).

Note

Radian is a dimensionless unit, therefore, moment of inertia values in \((\mathrm{kg}\cdot\mathrm{m^2})\) and \((\mathrm{N}\cdot\mathrm{m}\cdot\mathrm{s^2})\) are also consistent with this definition.

Initial speed

The initial angular speed \(\omega_0\), in \(\left( \frac{\mathrm{rad}}{\mathrm{s}} \right)\).

Initial angle

The initial angle \(\theta_0\), in radians. May be specified in order to provide proper initial conditions if absolute angles are measured anywhere in the system. Otherwise, this parameter can be left blank.

Probe Signals

Speed

The angular speed of the body.

Angle

The absolute angle of the body (wrapped between \(-\pi\) and \(\pi\)).