AddAttitude YPR
Adds attitude data based on a time-ordered set of YPR yaw, pitch, and roll angles defined with respect to the central body inertial VVLH reference axes (CBIVVLH).
Similarly to Euler angles, YPR angles specify attitude using three rotations in a chosen sequence: the rotation about the reference X axis is called roll (R), the rotation about the reference Y axis is called pitch (P), and the rotation about the reference Z axis is called yaw (Y). Sequences are identified using either numbers (1 is the X axis, 2 is the Y axis, 3 is the Z axis) or letters (R is the X axis, P is the Y axis, Y is the Z axis). Unlike Euler angles, the rotations are not made about axes defined by an earlier rotation. Instead, each rotation is made about the reference system's axes.
In YPR angles, the names yaw, pitch, and roll do NOT refer to the angles normally used in aviation; the terms yaw, pitch, and roll in aviation refer to 321 Euler angles.
Syntax
AddAttitude <ObjectPath> YPR {StartTime} {Sequence} <Yaw> <Pitch> <Roll>
Description
Use the AddAttitude YPR command to modify the attitude of a vehicle using yaw, pitch, and roll attitude data.
The {Sequence} parameter identifies the order of rotations, where the numbers 1, 2, and 3 correspond to the rotations about the central body inertial VVLH (CBIVVLH) X, Y, and Z axes, respectively. A rotation about the Z axis is considered to be yaw, about the Y axis is pitch and about the X axis is roll. Valid values for {Sequence} are 123, 132, 213, 231, 312, 321.
The angle values, <Yaw> <Pitch> <Roll>, are entered in degrees.
For valid {StartTime} values see Time Options.
The AddAttitude YPR command is similar to using an external attitude profile, except that the points are entered one at a time using this command.
The AddAttitude YPR command will use its default frame (CBIVVLH) and will ignore any reference frame set with the SetAttitude DataReference command.
For two or more inputs of attitude data, you must enter them with increasing times. If you attempt to enter attitude data that is dated prior to existing attitude data, the new entry is ignored. To clear old data, use the SetAttitude ClearData command.
Examples
To add a new line to the STK1 satellite's default attitude file in the Test scenario:
Return message
If activated, Connect returns an acknowledgment message.Group membership
This command belongs to the following group(s):
Version
10