Differential Gear

Differential Gear component

The Differential Gear component represents a differential gear that distributes rotational motion of the longitudinal axis (drive shaft) to two lateral axes (left and right shafts). The longitudinal motion is divided by the user defined gear ratio, and then split between the lateral shafts.

The differential model uses two Planet Planet Gear components and two Basic Gear components as shown in the diagram below.

Internal Structure

Internal Settings

 Component ${\mathbf{PPG}}_{\mathbf{1}}$ ${\mathbf{PPG}}_{\mathbf{2}}$ ${\mathbf{BG}}_{\mathbf{1}}$ ${\mathbf{BG}}_{\mathbf{2}}$ $r$ $\mathrm{ideal}=\mathbf{true}$ $\mathrm{ideal}=\mathbf{true}$ $\mathrm{ideal}=\mathbf{true}$ $\mathrm{ideal}=\mathbf{true}$ $\mathrm{ideal}=\mathbf{true}$ $\mathrm{ideal}=\mathbf{false}$  $\mathrm{ideal}=\mathbf{false}$ $\mathrm{ideal}=\mathbf{false}$ $\mathrm{ideal}=\mathbf{true}$ $\mathrm{ideal}=\mathbf{false}$

Connections

 Name Condition Description ID $-$ Flange to drive shaft drive $-$ Flange to left shaft left - Flange to right shaft right $\mathrm{ideal}\mathbf{=}\mathbf{false}$ Conditional real output port for power loss lossPower

Parameters

Symbol

Condition

Default

Units

Description

ID

$\mathrm{ideal}$

-

$\mathrm{true}$

-

Defines whether the component is:

true - ideal or

false - non-ideal

ideal

$r$

-

$1$

-

Driveshaft pinion/Crown ring gear ratio (DS/R)

ratio

data source

$\mathrm{ideal}=\mathbf{false}$

GUI

-

Defines the source for the loss data:

 • entered via GUI [GUI]
 • by an attachment [attachment]
 • by an external file [file]

datasourcemode

${n}_{\mathrm{pl}}$

$\mathrm{ideal}=\mathbf{false}$

$2$

$-$

Number of planet gears

numberofPlanets

${\mathrm{\eta }}_{R/\mathrm{DS}}\left({\mathrm{\omega }}_{\mathrm{DS}}^{}\right)$

ideal = false

data source = GUI

$\left[0,1,1\right]$

Defines Ring (crown)/Drive shaft pinion velocity dependant meshing efficiency as a function of ${\mathrm{\omega }}_{\mathrm{DS}}^{}$ .

The columns are:

[${\mathrm{\omega }}_{\mathrm{DS}}^{}$     (${\mathrm{\eta }}_{1}$(${\mathrm{\omega }}_{\mathrm{DS}}^{}$ )     ${\mathrm{\eta }}_{2}$(${\mathrm{\omega }}_{\mathrm{DS}}^{}$ )]

First column is angular velocity of the input driveshaft (${\mathrm{\omega }}_{\mathrm{DS}}^{}$)

Five options are available:

 • 1 by 1 array:

Entered value is taken as the constant efficiency for forward and backward cases

${\mathrm{\eta }}_{1}$(${\mathrm{\omega }}_{\mathrm{DS}}^{}$ ) =$\left({\mathrm{\omega }}_{\mathrm{DS}}^{}\right)$ =

 • 1 by 2 array:

First entered value is taken as the constant efficiency for forward case and the second for backward cases

${\mathrm{η}}_{1}$(${\mathrm{\omega }}_{\mathrm{DS}}^{}$ ) =(${\mathrm{\omega }}_{\mathrm{DS}}^{}$ ) =

 • 1 by 3 array:

First column is ignored and the second and third values are taken as constant efficiencies for forward and backward cases, respectively.

 • n by 2 array:

Second column is forward and backward efficiency

(${\mathrm{\omega }}_{\mathrm{DS}}^{}$ ) = (${\mathrm{\omega }}_{\mathrm{DS}}^{}$ ) = (${\mathrm{\omega }}_{\mathrm{DS}}^{}$ )

 • n by 3 array:

Second column is forward efficiency

${\mathrm{\eta }}_{1}$ (${\mathrm{\omega }}_{\mathrm{DS}}$ )

Third column is backward efficiency

(${\mathrm{\omega }}_{\mathrm{DS}}^{}$ )

meshinglossTable1

ideal = false

data source = attachment

-

Defines the velocity dependent meshing efficiency

First column is Drive Shaft angular velocity (${\mathrm{\omega }}_{\mathrm{DS}}$ )

(See $\left[{\mathrm{\eta }}_{R/\mathrm{DS}}\right]$ below)

data1

ideal = false

data source = file

-

fileName1

$\left[{\mathrm{\eta }}_{R/\mathrm{DS}}\right]$

ideal = false

data source = attachment or file

$\left[2,3\right]$

-

Defines the corresponding data columns used for forward efficiency (${\mathrm{\eta }}_{1}$) and backward efficiency (${\mathrm{\eta }}_{2}$)

Two options are available:

 • 1 by 1 array:

Data column corresponding to the column number is used for both forward and backward efficiency (

 • 1 by 2 array:

Data column corresponding to the first column number is used for forward efficiency (${\mathrm{\eta }}_{1}$) and

data column corresponding to the second column number is used for backward efficiency (${\mathrm{\eta }}_{2}$)

columns1

${\mathrm{\eta }}_{P/\mathrm{SG}}\left({\mathrm{\omega }}_{\mathrm{SG}}^{}\right)$${}$

ideal = false

data source = GUI



$\left[0,1,1\right]$

Defines Side Gears/Planets velocity dependant meshing efficiency as a function of ${\mathrm{\omega }}_{\mathrm{SG}}^{}$ .

The columns are:

[${\mathrm{\omega }}_{\mathrm{SG}}^{}$     (${\mathrm{\eta }}_{1}$(${\mathrm{\omega }}_{\mathrm{SG}}^{}$ )     ${\mathrm{\eta }}_{2}$(${\mathrm{\omega }}_{\mathrm{SG}}^{}$ )]

Five options are available:

 • 1 by 1 array:

Entered value is taken as the constant efficiency for forward and backward cases

${\mathrm{\eta }}_{1}$(${\mathrm{\omega }}_{\mathrm{SG}}^{}$) =$\left({\mathrm{\omega }}_{\mathrm{SG}}^{}\right)$ =

 • 1 by 2 array:

First entered value is taken as the constant efficiency for forward case and the second for backward cases

${\mathrm{η}}_{1}$(${\mathrm{\omega }}_{\mathrm{SG}}^{}$) =(${\mathrm{\omega }}_{\mathrm{SG}}^{}$ ) =

 • 1 by 3 array:

First column is ignored and the second and third values are taken as constant efficiencies for forward and backward cases, respectively

 • n by 2 array:

Second column is forward and backward efficiency

(${\mathrm{\omega }}_{\mathrm{SG}}^{}$ ) = (${\mathrm{\omega }}_{\mathrm{SG}}^{}$ ) = (${\mathrm{\omega }}_{\mathrm{SG}}^{}$ )

 • n by 3 array:

Second column is forward efficiency

${\mathrm{\eta }}_{1}$ (${\mathrm{\omega }}_{\mathrm{SG}}^{}$ )

Third column is backward efficiency

(${\mathrm{\omega }}_{\mathrm{SG}}^{}$ )

meshinglossTable2

ideal = false

data source = attachment

-

Defines the velocity dependent meshing efficiency

First column is Side Gear (left or right) angular velocity (${\mathrm{\omega }}_{\mathrm{SG}}$ )

(See $\left[{\mathrm{\eta }}_{P/\mathrm{SG}}\right]$ below)

data2

ideal = false

data source = file

-

fileName2

$\left[{\mathrm{\eta }}_{P/\mathrm{SG}}\right]$

ideal = false

data source = attachment or file

$\left[2,3\right]$

-

Defines the corresponding data columns used for forward efficiency (${\mathrm{\eta }}_{1}$) and backward efficiency (${\mathrm{\eta }}_{2}$).

Two options are available:

 • 1 by 1 array:

Data column corresponding to the column number is used for both forward and backward efficiency (

 • 1 by 2 array:

Data column corresponding to the first column number is used for forward friction torque (${\mathrm{\eta }}_{1}$) and data column corresponding to the second column number is used for backward friction torque (${\mathrm{\eta }}_{2}$)

columns4

${d}_{P\mathit{/}C}$

ideal = false

0

Linear damping in Planet/Carrier bearings

d

smoothness

$\mathrm{ideal}=\mathbf{false}$

Table points are linearly interpolated

-

Defines the smoothness of table interpolation

There are two options:

 • Table points are linearly interpolated
 • Table points are interpolated such that the first derivative is continuous

smoothness