IS-1500 User Guide
Thales Visionix, Inc.
MNL- 0024 (D)
Page 12 of 59
Figure 4 – InertiaCam Dimensions
The tracker reference frame (or body frame) is a predetermined point and orientation on the InertiaCam and stays fixed to it. It is
indicated by markings on the InertiaCam housing, shown in Figure 4. The XY marking at point A on the front of the housing indicates
the orientation of the positive X and Y axes. The positional origin is located and marked at the back of the housing as the corner of the
rectangle, indicated by point B. (Like the markings on the front, the long and short sides of the rectangle on the back also indicate the
direction of the positive X and Y axes, respectively).
To help illustrate this, the sfStudio 3D Data Display in Figure 5 shows a tracker that has just been initialized with the InertiaCam laying
on a flat surface so the Z axis of the tracker is in the direction of gravity, the same as the world frame. The world frame in this image
has been marked in yellow. Gray gridlines lie across as the XY plane. The axes of the body frame are colored green, blue, and red for
X, Y, and Z, respectively. Note that the X and Y axes of the tracker may not line up exactly with those of the world frame.
Figure 5 – Initialized Reference Frames