7.4.1. Body

The lists of Bodies include a result set about each body as position, velocity and acceleration.

(In the case of RFlex body, the plot data is defined the RFlex Body Reference Frame instead CM.)

Figure 7.89 Kinematic relationship for plot data of body

• Pos_TM: The magnitude of the translational displacement of the center marker in the inertia reference frame.

• Pos_TX, Pos_TY, Pos_TZ: The x, y, and z components of the translational displacement of the center marker in the inertia reference frame.

  \(\mathbf{r}_{icm}=\mathbf{r}_+\mathbf{s}_{icsm} = \mathbf{r}_i+\mathbf{A}_i\mathbf{s}_{icm}'\)

• Pos_PSI, Pos_THETA, Pos_PHI: The 3-1-3 Euler angle of the center marker measured in the inertia reference frame.

  \(\mathbf{A}_{icm}=\mathbf{R}_z(\theta)\mathbf{R}_x(\theta)\mathbf{R}_z(\psi)\)

• Pos_YAW, Pos_PITCH, Pos_ROLL: The 3-2-1 Euler angle of the center marker measured in the inertia reference frame.

  \(\mathbf{A}_{icm}=\mathbf{R}_z(\theta_{yaw})\mathbf{R}_x(\theta_{pitch})\mathbf{R}_z(\theta_{roll})\)

• Vel_TM: The magnitude of the translational velocity of the center marker in the inertia reference frame.

• Vel_TX, Vel_TY, Vel_TZ: The x, y, and z components of the translational velocity of the center marker in the inertia reference frame.

  \(\dot{\mathbf{r}}_{icm}=\dot{\mathbf{r}}_i+\mathbf{A}_i\tilde{\mathbf{\omega}_i} \mathbf{s}_{icsm}' = \mathbf{A}_i\dot{\mathbf{r}}_i+\mathbf{A}_i \tilde{\mathbf{\omega}_i}\mathbf{s}_{icm}'\)

• Vel_RM: The magnitude of the angular velocity of the center marker in the inertia reference frame.

• Vel_RX, Vel_RY, Vel_RZ: The x, y, and z components of the angular velocity of the center marker in the center marker reference frame.

  \(\mathbf{\omega}_i'=\mathbf{A}^T \cdot \mathbf{\omega}_i\)

• Acc_TM: The magnitude of the translational acceleration of the center marker in the inertia reference frame.

• Acc_TX, Acc_TY, Acc_TZ: The x, y, and z components of the translational acceleration of the center marker in the inertia reference frame.

  \(\ddot{\mathbf{r}}_{icm}=\mathbf{A}_i\ddot{\mathbf{r}}_i' + \mathbf{A}_i\tilde{\mathbf{\omega}_i}'\dot{\mathbf{r}}_i' + \mathbf{A}_i\tilde{\mathbf{\omega}_i}'\tilde{\mathbf{\omega}_i}'\mathbf{s}_{icsm}'+\mathbf{A}_i\tilde{\dot{\mathbf{\omega}}}_i'\)

• Acc_RM: The magnitude of the angular acceleration of the center marker in the inertia reference frame.

• Acc_RX, Acc_RY, Acc_RZ: The x, y, and z components of the angular acceleration of the center marker in the center marker reference frame.

  \(\dot{\mathbf{\omega}}_i'=\mathbf{A}^T \cdot \dot{\mathbf{\omega}}_i\)

• KineticEnergy: The Kinetic energy of the center marker with respect to the inertia reference frame.

  \(K=\frac{1}{2}m{{v}^{2}}\)

• PotentialEnergy: The Potential energy of the center marker with respect to the inertia reference frame.

  \(P=mgh\)