Description:

The coordinate system is right hand rule. X cross Y gives Z and Roll is right hand rule about X, Pitch is right hand rule about Y, and Yaw is right hand rule about Z.

Vector Storage:

All linear three vectors (LinPos, LinVel) store their values as [X, Y, Z].
All angular three vectors (AngVel) store their values as [Roll, Pitch, Yaw].
The transformation matrix TM is stored:

Pre-multiplying a local vector by the TM will generate the vector in global coordinates.

Multibody Dynamics, Link Numbers and 60 and 20 Length Vectors:

Please refer to Multibody Dynamics and 60 Length Vectors for information on 60
length vectors.

Methodology:

The prismatic models a translational mechanism. LocalJointAxis defines the axis about which the body translates. The LocalJointAxis is defined in the local coordinates of the upstream body's coordinate system.

The prismatic takes the input position, velocity, and acceleration from Side 3 adds in the position, velocity and acceleration of the joint and outputs the results on Side 1.

The prismatic also takes the internal force and moment from Side 1 and calculates the force and moment at Side 3 based on the current length of the joint.

A new link number is requested from the multibody solver and this is added to the list of link numbers in LinkNumber3 and output in LinkNumber1.

The prismatic calculates the force generated about the joint due to the perturbation of each degree of freedom. In addition it calculates the default force due to gravity, velocity, and external forces. The external force applied to the joint through ExternalJointForce is added to the default force.

The multibody solver calculates the actual joint acceleration, which is integrated and output in
JointVel and JointPos.
 

SimRealVar Force1[60] - Global Force (N)
SimRealVar Moment1[60] - Global Moment (Nm)

Outputs:

SimRealVar LinAccel1[60] - Global Linear Acceleration (m/s/s)
SimRealVar LinVel1[3] - Global Linear Velocity (m/s)
SimRealVar LinPos1[3] - Global Linear Position (m)
SimRealVar AngAccel1[60] - Global Angular Acceleration (rad/s/s)
SimRealVar AngVel1[3] - Global Angular Velocity (rad/s)
SimRealVar TM1[9] - Transformation Matrix (ND)
SimRealVar LinkNumber1[20] - Link Number Output (ND)
 

SimRealVar LocalJointAxis[3] - Local Joint Axis (ND)
 

SimRealVar LinAccel3[60] - Global Linear Acceleration (m/s/s)
SimRealVar LinVel3[3] - Global Linear Velocity (m/s)
SimRealVar LinPos3[3] - Global Linear Position (m)
SimRealVar AngAccel3[60] - Global Angular Acceleration (rad/s/s)
SimRealVar AngVel3[3] - Global Angular Velocity (rad/s)
SimRealVar TM3[9] - Transformation Matrix (ND)
SimRealVar LinkNumber3[20] - Link Number Output (ND)

Outputs:

SimRealVar Force3[60] - Global Force (N)
SimRealVar Moment3[60] - Global Moment (Nm)
 

SimRealVar ExternalJointForce - External Joint Force (N)

Outputs:

SimRealVar JointPos - Joint Position (m)
SimRealVar JointVel - Joint Velocity (m/s)

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