U3[i->j, {wi, pi}, {wj, pj}]
function defines a list of input arguments of DefineKinematicPair function for the universal joint definition between i and j links.
  • The kinematic pair is defined between i and j links where i and j are integers or strings.
  • If i (j) is integer the link name is generated as "linki" ("linkj") respectively.
  • The position and orientation of the joint markers are defined with {wi, pi} and {wj,pj}.
  • wi and wj are defining the axis vector of joint , while pi and pj defines the center point of the joints. The coordinates are referring the local reference coordinate system of link i and j respectively.
  • The axis vector of the joints could be specified with a list of coordinate or with string { "x" , "y" , "z" } representing the corresponding axes of the local reference frame.
  • Two joint variables defines the universal joint. Lets call them 1, 2 respectively. The universal joint is defined in such a way that 1 first rotates the upper link around the "z" axis of the joint marker than it rotates with 2 around the "x".
  • The following options can be given:
JointVariableAutomaticspecifies the symbol of the joint variable.
JointNameAutomaticspecifies the name of the kinematic pair.
JointLimitsAutomaticdefines the validity domain of the joint variable(s).
JointPoseAutomaticdefines the offset value(s) of the joint variable(s).
Parameters{}List of the simple parameters used in the kinematic pair's definition ( e.g {l0→10,l1→3} ).
CandidateLoopVariablesAutomaticList of driving variable that will be used as loop variables in case of loop closing kinematic pair definition.
WorkingPrecisionMachinePrecisionWorkingPrecision is an option for various numerical operations which specifies how many digits of precision should be maintained in internal computations.
AccuracyGoalAutomaticAccuracyGoal is an option for various numerical operations which specifies how many effective digits of accuracy should be sought in the final result.
MaxIterationsAutomaticMaxIterations is an option that specifies the maximum number of iterations that should be tried in various built-in functions and algorithms.
Load the LinkageDesigner package
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Define a universal joint between link0 and link1 as the figure shows
Define a arguments of the rotational joint
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Define the mechanism
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Display the linkage and the LLRFs of link1 and link2
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