Node MagneticTorqueNode#

Defined in mime.nodes.magnetic._torque.MagneticTorqueNode.

Algorithm MIME-NODE-114.

The torque of a magnetic field on a body’s permanent moment, tau = m x B, as a wrench about the centre of mass with no force.

Governing equations#

\[ \boldsymbol{\tau} = \mathbf{m} \times \mathbf{B}, \quad \mathbf{m} = R(\mathbf{q}) \, \mathbf{m}_{b} \]

Discretisation#

none declared; a node whose order depends on its construction declares it with the discretization_order() hook, which is read from a built node.

Assumptions#

  • A point dipole with a rigid, permanent moment fixed in the body

  • The field is read at the body’s centre of mass: it is taken uniform across the body

  • The body’s orientation is the one read at the start of the step, so the torque of a step turns the body as it stood after the step before

Limitations#

none declared

Declared regimes (not evidenced here)#

none declared

References#

[@Ling2016UniversityPhysics2]

Symbols#

Symbol

Kind

Name

Units

Implemented by

\(\boldsymbol{\tau}\)

state

wrench

N; N m

mime.nodes.magnetic._torque.MagneticTorqueNode.advance

\(\mathbf{B}\)

input

flux_density

T

mime.nodes.magnetic._torque.MagneticTorqueNode.advance

\(\mathbf{m}_{b}\)

parameter

moment

A m^2

mime.nodes.magnetic._torque.MagneticTorqueNode.advance

\(\mathbf{q}\)

input

pose

m; 1

mime.nodes.magnetic._torque.MagneticTorqueNode.advance

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