In order to get insight in the friction phenomena, a friction model should incorporate as much friction phenomena and behave as much as real friction. In the table below an overview of the different models of the 20-sim library with respect to the friction phenomena is given.
|
Coulomb model |
Coulomb, viscous model |
static, Coulomb, viscous model |
static, Coulomb, viscous, Stribeck model |
LuGre model |
static friction phenomena |
|
|
|
|
|
Coulomb |
V |
V |
V |
V |
V |
viscous |
|
V |
V |
V |
V |
static |
|
|
V |
V |
V |
Stribeck |
|
|
|
V |
V |
dynamic friction phenomena |
|
|
|
|
|
pre-sliding displacement |
|
|
|
|
V |
varying break-away force |
|
|
|
|
V |
frictional lag |
|
|
|
|
V |
From this overview it can be seen that all friction phenomena are incorporated in the LuGre model. From the literature, it is known that the behavior of the LuGre model is much alike real friction.
For most engineering applications, a static friction model, for example a static, Coulomb, viscous friction model, is sufficient. If all friction effects should be modeled, the LuGre friction model seems best suited.