SlipBasedWheelJoint
Slip-Friction based wheel joint
Library
PlanarMechanics/VehicleComponents/Wheels
Description
The ideal wheel joint models the behavior of a wheel rolling on a x,y-planewhose contact patch has slip-dependent friction characteristics. This is anapproximation for wheels with a rim and a rubber tire.
The force depends with friction characteristics on the slip.The slip is split into two components:
- lateral slip: the lateral velocity divided by the rolling velocity.
- longitudinal slip: the longitudinal slip velocity divided by the rolling velocity.
For low rolling velocity this definitions become ill-conditioned.Hence a dry-friction model is used for low rolling velocities.
The radius of the wheel can be specified by the parameter radius.The driving direction (for phi = 0) can be specified by theparameter r. The normal load is set N.
The wheel contains a 2D connector frame_a for the steeringon the plane. The rolling motion of the wheel can be actuated by the 1D connectorflange_a.
In addition there is an input for a dynamic component of the normal load.
For examples of usage see the localExamples package.
Parameters
| Name | Label | Description | Data Type | Valid Values |
|---|---|---|---|---|
mo_useHeatPort | useHeatPort | = true, if heatPort is enabled | Number | 0 |
mo_radius | radius | Wheel radius | Scalar | |
mo_r | r | Driving direction of the wheel at angle phi = 0 | Vector of size 2 | |
mo_N | N | Base normal load | Scalar | |
mo_vAdhesion_min | vAdhesion_min | Minimum adhesion velocity | Scalar | |
mo_vSlide_min | vSlide_min | Minimum sliding velocity | Scalar | |
mo_sAdhesion | sAdhesion | Adhesion slippage | Scalar | |
mo_sSlide | sSlide | Sliding slippage | Scalar | |
mo_mu_A | mu_A | Friction coefficient at adhesion | Scalar | |
mo_mu_S | mu_S | Friction coefficient at sliding | Scalar | |
mo_l | l | Length of r | Scalar | |
mo_e | e | Unit vector in direction of r | Vector of size 2 | |
mo_phi_roll | phi_roll | phi_roll | Structure | |
mo_phi_roll/fixed | fixed | Cell of scalars | true | |
mo_phi_roll/start | start | Cell of scalars | ||
mo_w_roll | w_roll | w_roll | Structure | |
mo_w_roll/fixed | fixed | Cell of scalars | true | |
mo_w_roll/start | start | Cell of scalars | ||
mo_v_lat | v_lat | v_lat | Structure | |
mo_v_lat/fixed | fixed | Cell of scalars | true | |
mo_v_lat/start | start | Cell of scalars | ||
mo_v_long | v_long | v_long | Structure | |
mo_v_long/fixed | fixed | Cell of scalars | true | |
mo_v_long/start | start | Cell of scalars | ||
mo_v_slip_long | v_slip_long | v_slip_long | Structure | |
mo_v_slip_long/fixed | fixed | Cell of scalars | true | |
mo_v_slip_long/start | start | Cell of scalars | ||
mo_v_slip_lat | v_slip_lat | v_slip_lat | Structure | |
mo_v_slip_lat/fixed | fixed | Cell of scalars | true | |
mo_v_slip_lat/start | start | Cell of scalars | ||
mo_animate | animate | = true, if animation shall be enabled | Scalar | true |
| Name | Label | Description | Data Type | Valid Values |
|---|---|---|---|---|
mo_stateSelect | stateSelect | Priority to use acceleration as states | Structure | |
mo_stateSelect/choice1 | StateSelect.never | Number | 0 | |
mo_stateSelect/choice2 | StateSelect.avoid | Number | 0 | |
mo_stateSelect/choice3 | StateSelect.default | Number | 0 | |
mo_stateSelect/choice4 | StateSelect.prefer | Number | 0 | |
mo_stateSelect/choice5 | StateSelect.always | Number | 0 |
| Name | Label | Description | Data Type | Valid Values |
|---|---|---|---|---|
mo_zPosition | zPosition | Position z of the body | Scalar | |
mo_diameter | diameter | Diameter of the rims | Scalar | |
mo_width | width | Width of the wheel | Scalar | |
mo_specularCoefficient | specularCoefficient | Reflection of ambient light (= 0: light is completely absorbed) | Scalar |
| Name | Label | Description | Data Type | Valid Values |
|---|---|---|---|---|
mo__nmodifiers | Number of Modifiers | Specifies the number of modifiers | Number | |
mo__modifiers | Modifiers | Add new modifier | Structure | |
mo__modifiers/varname | Variable name | Cell of strings | 'lossPower' | |
mo__modifiers/attribute | Attribute | Cell of strings | 'start' | |
mo__modifiers/value | Value |
Ports
| Name | Type | Description | IO Type | Number |
|---|---|---|---|---|
frame_a | implicit | input | 1 | |
flange_a | implicit | input | 2 | |
dynamicLoad | implicit | input | 3 | |
Port 4 | implicit | Optional port to which dissipated losses are transported in form of heat | input | mo_useHeatPort |