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--- visual3d:documentation:pipeline:model_based_data_commands:angular_momentum_pt [2025/12/03 20:14] – Cleaned up page. wikisysop
+++ visual3d:documentation:pipeline:model_based_data_commands:angular_momentum_pt [2026/06/02 14:14] (current) – ↷ Links adapted because of a move operation 172.204.27.30
@@ Line 3: / Line 3: @@
 This example demonstrates how to calculate the angular momentum of a [[visual3d:documentation:modeling:segments:segment_overview|segment]] about an arbitrary point.
-**Note**: It is very important to note that the total body angular momentum is not calculated by summing the [[Visual3D:Documentation:Pipeline:Model_Based_Data_Commands:ANGULAR_MOMENTUM|ANGULAR_MOMENTUM]] for each segment because this model-based item represents the angular momentum of each segment about its [[visual3d:documentation:modeling:segments:segment_properties#inertial_properties|own centre of mass]]. To calculate the total body angular momentum you must calculate the angular momentum for each segment about the same axis, such as the total body center of mass. The equations in the [[#Angular_Momentum:_About_Total_Body_Center_of_Mass|About Total Body Center of Mass]] section describe how to do this.
+**Note**: It is very important to note that the total body angular momentum is not calculated by summing the [[visual3d:documentation:visual3d_signal_types:link_model_based_data_type:angular_momentum|ANGULAR_MOMENTUM]] for each segment because this model-based item represents the angular momentum of each segment about its [[visual3d:documentation:modeling:segments:segment_properties#inertial_properties|own centre of mass]]. To calculate the total body angular momentum you must calculate the angular momentum for each segment about the same axis, such as the total body center of mass. The equations in the [[#Angular_Momentum:_About_Total_Body_Center_of_Mass|About Total Body Center of Mass]] section describe how to do this.
 ===== Calculating Angular Momentum =====
-Visual3D's built in [[Visual3D:Documentation:Pipeline:Model_Based_Data_Commands:ANGULAR_MOMENTUM|ANGULAR_MOMENTUM]] command calculates the angular momentum of a segment about the segment's center of mass, but angular momentum can also be calculated about a different point in space.
+Visual3D's built in [[visual3d:documentation:visual3d_signal_types:link_model_based_data_type:angular_momentum|ANGULAR_MOMENTUM]] command calculates the angular momentum of a segment about the segment's center of mass, but angular momentum can also be calculated about a different point in space.
 ==== About a Segment's Centre of Mass ====
@@ Line 41: / Line 41: @@
 ===== Example =====
-This example script demonstrates how to calculate a segment's angular momentum about a point, such as the [[visual3d:documentation:pipeline:model_based_data_commands:model_cog|model centre of mass]], by the following steps:
+This example script demonstrates how to calculate a segment's angular momentum about a point, such as the [[visual3d:documentation:visual3d_signal_types:link_model_based_data_type:model_cog|model centre of mass]], by the following steps:
   - Compute //r//
   - Compute //mv//
   - Compute //r// x //mv//
-  - Compute the angular momentum of the segment using the [[Visual3D:Documentation:Pipeline:Model_Based_Data_Commands:ANGULAR_MOMENTUM|Angular Momentum]] command
+  - Compute the angular momentum of the segment using the [[visual3d:documentation:visual3d_signal_types:link_model_based_data_type:angular_momentum|Angular Momentum]] command
   - Compute //Iw// x (//r// x //mv//)
@@ Line 65: / Line 65: @@
 ;
+! Nested Loops
+! Outer Loop gets an active segment
 For_Each
 /ITERATION_PARAMETER_NAME=SEG_NAME
@@ Line 70: / Line 72: @@
 ;
-! compute the R for (r x mv)
+! compute the r for (r x mv)
 Evaluate_Expression
-/EXPRESSION=vector((Kinetic_Kinematic::&::SEG_NAME& ::CGPos::X - KINETIC_KINEMATIC::MODEL::CenterOfMass::X ),
+/EXPRESSION=vector((Kinetic_Kinematic::&::SEG_NAME&:&:CGPos::X - KINETIC_KINEMATIC::MODEL::CenterOfMass::X ), (Kinetic_Kinematic::&::SEG_NAME&:&:CGPos::Y - KINETIC_KINEMATIC::MODEL::CenterOfMass::Y), (Kinetic_Kinematic::&::SEG_NAME&:&:CGPos::Z - KINETIC_KINEMATIC::MODEL::CenterOfMass::Z))
- (Kinetic_Kinematic::&::SEG_NAME& ::CGPos::Y - KINETIC_KINEMATIC::MODEL::CenterOfMass::Y),
- (Kinetic_Kinematic::&::SEG_NAME& ::CGPos::Z - KINETIC_KINEMATIC::MODEL::CenterOfMass::Z))
 /RESULT_NAME=::SEG_NAME&_R
 ! /RESULT_TYPE=DERIVED
@@ Line 82: / Line 82: @@
 ! compute mv
 Evaluate_Expression
-/EXPRESSION=(MODEL::SEGMENT::&::SEG_NAME&:&:MASS)*(Kinetic_Kinematic::&::SEG_NAME& ::CGVel - DERIVED::COM::CENTEROFMASS_VEL )
+/EXPRESSION=(MODEL::SEGMENT::&::SEG_NAME&:&:MASS)*(Kinetic_Kinematic::&::SEG_NAME&:&:CGVel - DERIVED::COM::CENTEROFMASS_VEL)
 /RESULT_NAME=::SEG_NAME&_mv
 ! /RESULT_TYPE=DERIVED
@@ Line 88: / Line 88: @@
 ;
-! compute rxmv
+! compute r x mv
 Evaluate_Expression
 /EXPRESSION=cross(DERIVED::PROCESSED::&::SEG_NAME&_R, DERIVED::PROCESSED::&::SEG_NAME&_mv)
@@ Line 96: / Line 96: @@
 ;
+! compute Iw
 Compute_Model_Based_Data
 /RESULT_NAME=::SEG_NAME&_IW
@@ Line 114: / Line 115: @@
 ;
-! compute Iw x rxmv
+! compute Iw x (r x mv)
 Evaluate_Expression
 /EXPRESSION=LINK_MODEL_BASED::ORIGINAL::&::SEG_NAME&_IW + DERIVED::PROCESSED::&::SEG_NAME&_rxmv
@@ Line 121: / Line 122: @@
 /RESULT_FOLDER=Momentum_Contribution
 ;
 End_For_Each
 /ITERATION_PARAMETER_NAME=SEG_NAME