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Torsion Spring

Purpose

Ideal torsion spring

Library

Mechanical / Rotational / Components

Description

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The Torsion Spring models an ideal linear spring in a rotational system described with the following equations:

  τ  =  - c ⋅Dθ
D θ  =  θ- θ0
d
dtθ  =  ω

where τ   is the torque flow from the unmarked towards the marked flange, θ   is the angle of the marked flange with respect to the unmarked one, and θ0   is the equilibrium flange displacement.
Note  An torsion spring may not be connected in series with a torque source. Doing so would create a dependency between an input variable (the source torque) and a state variable (the spring torque) in the underlying state-space equations.

Parameters

Spring constant
The spring rate or stiffness c  , in Nrmad  .
Equilibrium (unstretched) displacement
The displacement θ0   between the two flanges of the unloaded spring, in radians.
Initial deformation
The initial deformation (torsion) Dθ0    of the spring, in radians.

Probe Signals

Torque
The spring torque τ  , in Newton meters (Nm).
Deformation
The spring deformation D θ  , in radians.