RTSX Help: joint and robot friction

jfriction, rfriction, nofriction

Get/remove joint and robot frictions


  • tau = jfriction(l, qd)
  • tau = rfriction(robot, qd)
  • robot = nofriction(robot, options)

Input/output Arguments

  • robot — n-link robot data structure created with SerialLink( )
  • l — robot link data structure
  • qd — link velocity


  • ‘viscous’ — select viscous friction
  • ‘coulomb’ — select coulomb friction
  • ‘all’ — select all types of friction


  • tau = jfriction(l, qd) computes joint friction/torque for link velocity qd.
  • tau = rfriction(l, qd) computes a vector of joint friction forces/torques for the robot moving with joint velocities qd.
  • robot = nofriction(robot, options) removes friction(s) from a robot depending on the selected option: viscous, coulomb, or all.

See also