Drake
drake::multibody::multibody_plant Namespace Reference

internal

Classes

class  ContactResults
A container class storing the contact results information for each contact pair for a given state of the simulation. More...

class  ContactResultsToLcmSystem
A System that encodes ContactResults into a lcmt_contact_results_for_viz message. More...

class  CoulombFriction
Parameters for Coulomb's Law of Friction, namely: More...

class  MultibodyPlant
MultibodyPlant is a Drake system framework representation (see systems::System) for the model of a physical system consisting of a collection of interconnected bodies. More...

class  PointPairContactInfo
A class containing information regarding contact response between two bodies including: More...

Functions

template<typename T >
CoulombFriction< TCalcContactFrictionFromSurfaceProperties (const CoulombFriction< T > &surface_properties1, const CoulombFriction< T > &surface_properties2)
Given the surface properties of two different surfaces, this method computes the Coulomb's law coefficients of friction characterizing the interaction by friction of the given surface pair. More...

Function Documentation

 CoulombFriction drake::multibody::multibody_plant::CalcContactFrictionFromSurfaceProperties ( const CoulombFriction< T > & surface_properties1, const CoulombFriction< T > & surface_properties2 )

Given the surface properties of two different surfaces, this method computes the Coulomb's law coefficients of friction characterizing the interaction by friction of the given surface pair.

The surface properties are specified by individual Coulomb's law coefficients of friction. As outlined in the class's documentation for CoulombFriction, friction coefficients characterize a surface pair and not individual surfaces. However, we find it useful in practice to associate the abstract idea of friction coefficients to a single surface. Please refer to the documentation for CoulombFriction for details on this topic.

More specifically, this method computes the contact coefficients for the given surface pair as:

  μ = 2μₘμₙ/(μₘ + μₙ)


where the operation above is performed separately on the static and dynamic friction coefficients.

Parameters
 [in] surface_properties1 Surface properties for surface 1. Specified as an individual set of Coulomb's law coefficients of friction. [in] surface_properties2 Surface properties for surface 2. Specified as an individual set of Coulomb's law coefficients of friction.
Returns
the combined friction coefficients for the interacting surfaces.