*SetJointFrictionLugre() - single joint
Sets the friction properties for a joint with friction.
*Applicable for the MotionSolve SolverMode only.
Syntax
*SetJointFrictionLugre(varname, bristle_stiffness,
damping_effects, viscous_effects)
Arguments
- varname
- The variable name of the joint.
- bristle_stiffness
- Specifies the LuGre bristle stiffness to be used. See Comments below.
- damping_effects
- Specifies the LuGre damping coefficient for the stiction regime. See Comments below.
- viscous_effects
- Specifies the coefficient for the viscous damping force that occurs when relative sliding actually begins. See Comments below.
Example
*BeginMDL( the_model, "Model" )
*StandardInclude(FILE)
*Point( p_block, "Block" )
*Body( b_0, "Block", p_block, , , , )
*TransJoint( j_0, "Translation", b_0, B_Ground, p_block, VECTOR, V_Global_X )
*SetBodyInertia( b_0, 1.0, 1000.0, 1000.0, 100.0, 0.0, 0.0, 0.0 )
*Set( b_0.usecm, true )
*SetJointFriction( j_0, true, 0.3, 0.25, ACTIVE_STATIC, 0.1, 0.01, SLIDING_ONLY, PRELOAD, NO_REACTION_FORCE, NO_BENDING_MOMENT, , 1000, 10, , , , 0.0, 1.0, 1.0, 1.0, 1.0 )
*SetJointFrictionLugre( j_0, 110, 0.31, 0.0005 )
*EndMDL()
Context
Comments
- bristle_stiffness
- Specifies the bristle stiffness in the LuGre model. It models the stiffness resisting micro-deformation in the friction element.
- damping_effects
- Defines the damping coefficient for the pre-displacement (or stiction) regime. Its main role is to damp out bristle vibrations in the pre-displacement regime.
- viscous_effects
- Represents viscous damping. This is primarily responsible for the increase in friction force with the increase in the slip velocity.