Chapter 3 SPAN Operation
OEM7 SPAN Installation and Operation User Manual v14
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Figure 35: Operating Gimbal
3.11.2 How to Use Variable Lever Arm
The variable lever arm functionality is simple to use in a SPAN system. It requires the input of gimbal angles
from the camera mount or platform that the IMU is mounted on. After that is provided, the system will auto-
matically compute the variable lever arm and produce several messages for output.
Ensuring a proper variable lever arm is important for SPAN performance.
Basic I/O
The variable lever arm functionality is based on the input of the
INPUTGIMBALANGLE
command. This com-
mand specifies the right-handed rotation angles from the
mount body frame (m)
to the
gimbal body frame (g)
,
with the order of rotations Z-X-Y. Entering this command will automatically cause the system to rotate the static
lever arm into the latest gimballed frame. The update rate of the variable lever arm depends on the rate of the gim-
bal commands which can be entered at 1 to 50 Hz. If an
INPUTGIMBALANGLE
command is not received for
over 1 second then the system will return to using the static lever arm.
In addition to using the variable lever arm internally, the following information is available to the user.