Class for calculating Instantaneous Axis of Rotation

This is a custom class_template that makes it easy to calculate and display the intantaneous axis of rotation between two bodies in an AnyBody Model.

You can read more about the code in this blog post on AnyScript.org

Here is a short example on how to use the class. First add the following to the top of your main file.

#include "<ANYBODY_PATH_TOOLBOX>/Rotations/InstantaneousAxisOfRotation.any"

Then add the InstantaneousAxisOfRotation class in one of your studies.

#include "<ANYBODY_PATH_TOOLBOX>/Rotations/InstantaneousAxisOfRotation.any"

Main = {


  // This is a simple example of using the InstantaneousAxisOfRotation class
  // to the calculate and vizualize the instantaneous axis of rotation 
  // between Body1 and Body2
  InstantaneousAxisOfRotation IAOR (AnyRefFrame& Body1, AnyRefFrame& Body2) = 
  {
      // The sphere drawn at the mid point of the vizualized axis.
      #var AnyVar SphereSize=0.02;
      
      // The length of the vizualized axis
      #var AnyVar AxisLength=2;
  
      // The line thickness of the vizualized axis.
      #var AnyVar LineThickness = 0.005;       

   };

Output

The object will IAOR object will plot the axis, and provide the following outputs:

Output variable	Type	Desciption
RotationAxisDirections	AnyVec3	The mid point on axis in Body1 coordinates
RotationMagnitude	AnyVec3	The direction of the axis in Body1 coordinates
rc_2	AnyVec3	Point on axis closest to Body2
rc_1	AnyVec3	Point on axis closest to Body1
MotionPitch	AnyVar	The ratio of linear motion to angular motion
rc_dot	AnyVec3	The linear velocity along the axis of rotation
omega	AnyVec3	Anuglar velocity vector of Body2 wrt. Body1
r	AnyVec3	Position of Body2 wrt. Body1
r_dot	AnyVec3	Linear velocity of Body2 wrt. Body1