Counter-Rotating Planetary Gear
Counter-Rotating Planetary Gear component
The Counter-Rotating Planetary Gear is based on the Planetary Gear component (see Planetary Gear). It has a set of two meshing planet gears on a single carrier where the first planet meshes with the sun gear and the second planet meshes with the ring gear. Three gear ratios must be provided: Ring/Planet(1), Planet(2)/Sun, and Planet(2)/Planet(1). This component is modeled using two Planet Planet Gears and one Planet Ring Gear as shown in the diagram below.
Internal Structure
Internal Settings
Component
PPG1
PPG2
PRG1
rP1/S , rR/P2, rP2/P1
rO/I = rP1/S
rO/I = rP2/P1
rR/P = rR/P2
ideal=true
ideal=false
same loss data=true
ηω, d
ηωI/C = ηω
d = d
d = 0
ηωR/C = ηω
same loss data= false
ηP1/SωS/C, ηR/P2ωR/C, ηP2/P1ωP1/C, dP1/C, dP2/C
ηωI/C = ηP1/SωS/C
d = dP1/C
ηωI/C = ηP2/P1ωP1/C
ηωR/C = ηR/P2ωR/C
d = dP2/C
Connections
Name
Condition
Description
ID
Carrier
−
Carrier flange
carrier
Planet1
planet port=true
Planet1 flange
planet1
Planet2
Planet2 flange
planet2
Ring
Ring flange
ring
Sun
Sun flange
sun
Loss Power
Conditional real output port for power loss
lossPower
Parameters
Symbol
Default
Units
ideal
-
true
Defines whether the component is:
true - ideal or
false - non-ideal
data source
GUI
Defines the source for the loss data:
entered via GUI [GUI]
by an attachment [attachment]
by an external file [file]
datasourcemode
same loss data
Defines whether one efficiency data table is used for all meshing loss calculations [same loss data=true] or the efficiency of each meshing gear pair is given by a separate data table [same loss data=false].
SameMeshingEfficiency
rP1/S
1
Planet 1/Sun Gear ratio
ratio1
rR/P2
4
Ring/Planet2 Gear ratio
ratio2
rP2/P1
Planet2/Planet1 Gear ratio
ratio3
npl
Number of planet pair gears
A planet pair consists of a set of Planet 1 and Planet 2 gears
numberofPlanets
ηω
same loss data = true
data source = GUI
0,1,1
rads,−,−
Defines all velocity dependant meshing efficiencies.
The columns:
[ω (η1 (ω ) η2 (ω )]
Five options are available:
1 by 1 array:
Entered value is taken as the constant efficiency for forward and backward cases
η1 (ω ) = η2 (ω ) = η
1 by 2 array:
First entered value is taken as the constant efficiency for forward case and the second for backward cases
η1 (ω) = η1 , η2 (ω ) = η2
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:
2nd column is forward and backward efficiency
η (ω) = η1 (ω ) = η2(ω )
n by 3 array:
2nd column is forward efficiency
η1 (ω)
3rd column is backward efficiency
η2 (ω )
meshinglossTable4
data source = attachment
Defines velocity dependant meshing efficiency
First column is angular velocity (ω)
(See col η below)
data4
data source = file
fileName4
col η
data source = attachment or file
2,3
Defines the corresponding data columns used for forward efficiency (η1) and backward efficiency (η2 )
Two options are available:
Data column corresponding to the column number is used for both forward and backward efficiency η=η1 = η2
Data column corresponding to the first column number is used for forward efficiency ( η1)
and data column corresponding to the second column number is used for backward efficiency ( η2)
columns4
ηR/P2ωR/C
same loss data = false
rads,−, −
Defines Ring/Planet2 velocity dependant meshing efficiency as a function of ωR/C .
The columns are:
[ωR/C (η1(ωR/C ) η2(ωR/C )]
First column is angular velocity of the ring gear w.r.t. the carrier (ωR/C)
η1(ωR/C ) = η2ωR/C = η
η1(ωR/C ) = η1 , η2(ωR/C ) = η2
First column is ignored and the second and third values are taken as constant efficiencies for forward and backward cases, respectively.
Second column is forward and backward efficiency
η (ωR/C ) = η1 (ωR/C ) = η2 (ωR/C )
Second column is forward efficiency
η1 (ωR/C )
Third column is backward efficiency
η2 (ωR/C )
meshinglossTable2
Defines the velocity dependent meshing efficiency
First column is angular velocity (ωR/C )
(See col ηR/P2 below)
data2
fileName2
col ηR/P2
Defines the corresponding data columns used for forward efficiency (η1) and backward efficiency (η2)
Data column corresponding to the column number is used for both forward and backward efficiency η1=η2 = η
Data column corresponding to the first column number is used for forward efficiency (η1) and
data column corresponding to the second column number is used for backward efficiency (η2)
columns2
ηP1/SωS/C
Defines Planet1/Sun velocity dependant meshing efficiency as a function of ωS/C .
[ωS/C (η1(ωS/C ) η2(ωS/C )]
First column is angular velocity of the sun gear w.r.t. carrier (ωS/C)
η1(ωS/C ) = η2ωS/C = η
η1(ωS/C ) = η1 , η2(ωS/C ) = η2
η (ωS/C ) = η1 (ωS/C ) = η2 (ωS/C )
η1 (ωS/C )
η2 (ωS/C )
meshinglossTable1
First column is angular velocity (ωS/C )
(See col ηP1/S below)
data1
fileName1
col ηP1/S
Defines the corresponding data columns used for forward (η1) and backward (η2) efficiency
Data column corresponding to the column number is used for both forward and backward efficiency (η1=η2 = η)
columns1
ηP2/P1/ωP1/C
Defines Planet2/Planet1 velocity dependant meshing efficiency as a function of ωP1/C .
[ωP1/C (η1(ωP1/C ) η2(ωP1/C )]
First column is angular velocity of the sun gear w.r.t. carrier (ωP1/C)
η1(ωP1/C ) = η2ωP1/C = η
η1(ωP1/C ) = η1 , η2(ωP1/C ) = η2
η (ωP1/C ) = η1 (ωP1/C ) = η2 (ωP1/C )
η1 (ωP1/C )
η2 (ωP1/C )
meshinglossTable3
First column is angular velocity (ωP1/C )
(See col ηP2/P1 below)
data3
fileName3
col ηP2/P1
columns3
dP1/C
0
N⋅mrads
Linear damping in planet1/carrier bearings
d1
dP2/C
Linear damping in planet2/carrier bearings
d2
d
Linear damping in planet/carrier bearing
d4
smoothness
Table points are linearly interpolated
Defines the smoothness of table interpolation
There are two options:
Table points are interpolated such that the first derivative is continuous
See Also
Driveline Library Overview
MapleSim Library Overview
1-D Mechanical Overview
Planetary Gear Sets
Dual Ratio Planetary Gear
Planet Planet Gear
Planet Ring Gear
Planetary Gear
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