# Force: Joint Friction

Command ElementThe Force_JointFriction command can be used to modify the parameters of the model element.

## Format

```
<Force_JointFriction
id = "integer"
[ mu_static = "real" ]
[ mu_dynamic = "real" ]
[ max_stiction_deform = "real" ]
[ stiction_trans_vel = "real"]
[ inputs = "
```*4-bit integer"* ]
[ torque_preload = "real" ]
[ friction_arm = "real" ]
[ bending_reaction_arm = "real" ]
[ pin_radius = "real" ]
/>

```
<Force_JointFriction
id = "integer"
[ mu_static = "real" ]
[ mu_dynamic = "real" ]
[ max_stiction_deform = "real" ]
[ stiction_trans_vel = "real"]
[ inputs = "
```*4-bit integer"* ]
[ torque_preload = "real" ]
[ ball_radius = "real" ]
/>

```
<Force_JointFriction
id = "integer"
[ mu_static = "real" ]
[ mu_dynamic = "real" ]
[ max_stiction_deform = "real" ]
[ stiction_trans_vel = "real" ]
[ inputs = "
```*4-bit integer "* ]
[ force_preload = "real" ]
[ reaction_arm = "real" ]
[ initial_overlap = "real" ]
/>

```
<Force_JointFriction
id = "integer"
[ mu_static = "real" ]
[ mu_dynamic = "real" ]
[ max_stiction_deform = "real" ]
[ stiction_trans_vel = "real" ]
[ inputs = "
```*4-bit intege**r" *]
[ force_preload = "real" ]
[ torque_preload = "real" ]
[ pin_radius = "real" ]
[ initial_overlap = "real" ]
/>

```
<Force_JointFriction
id = "integer"
[ mu_static = "real" ]
[ mu_dynamic = "real" ]
[ max_stiction_deform = "real"]
[ stiction_trans_vel = "real"]
[ inputs = "
```*4-bit integer"* ]
[ torque_preload = "real" ]
[ friction_arm = "real" ]
[ bending_reaction_arm = "real" ]
[ pin_radius = "real" ]
/>

## Attributes

`id`- Element identification number, (integer > 0). This number is unique among all Force_JointFriction elements.
`mu_static`- Specifies the static friction coefficient, (μ
_{s}), in the joint. `mu_dynamic`- Specifies the dynamic friction coefficient,
(μ
_{d}), in the joint. `max_stiction_deform`- Specifies the maximum deformation that can occur in a joint for static friction or stiction regime.
`stiction_trans_vel`- Real value of the absolute velocity below, which the friction transitions from dynamic friction to static friction.
`inputs`- A 4-bit integer value that specifies the input forces to the friction model. By default, all the preload and joint reaction forces are included. Valid values are 0 or 1 for each bit.
`force_preload`- Specifies the preload friction force for Translational and Cylindrical joints.
`torque_preload`- Specifies the preload friction torque for Revolute, Cylindrical, Universal and Spherical joints.
`friction_arm`- Specifies the moment arm used to compute axial friction torque in revolute, universal joints.
`reaction_arm`- Specifies the moment arm of the reaction torque about the Translation joint axial axes.
`bending_reaction_arm`- Specifies the moment arm to compute the bending moment in Revolute, Hooke and Universal joints.
`pin_radius`- Specifies the radius of the pin for Revolute, Cylindrical, Hooke and Universal joints.
`ball_radius`- Specifies the radius of the Spherical joint.
`initial_overlap`- Specifies the initial overlap of the sliding parts in Translation and Cylindrical joints.
`overlap_delta`- Specifies friction characteristics in the sliding joint.