Terminology - Kauai Labs VMX-pi User Manual

Guidance
Best Practices
Using the VMX-pi yaw angle before calibration completes may result in errors in robot control.
To avoid this situation, your robot software should verify that calibration has completed before
using VMX-pi IMU data.
3) Protect the Circuitry
VMX-pi contains sensitive circuitry. The VMX-pi circuit board should be handled carefully.
An enclosure is recommended to protect the VMX-pi circuit board from excessive handling,
"swarf", electro-static discharge (ESD) and other elements that could potentially damage VMX-
pi circuitry.
5) Provide a "Zero Yaw" feature (for Field-Oriented Drive)
The VMX-pi gyro "yaw" angle will
does not normally impact the robot during a typical FRC match, if using field-oriented drive
during extended practice sessions it may be necessary to periodically "zero" the yaw. Drivers
should be provided a simple way (e.g., a joystick button) with which to zero the yaw.
6) If possible, mount VMX-pi near the center of rotation
Since VMX-pi measures rotation, errors in the measured angles can occur if VMX-pi is mounted
at a point not near the robot center of rotation. For optimal results, VMX-pi should be mounted
at the robot's center of rotation. If VMX-pi cannot be mounted near the robot's center of
rotation, the offset from the center of rotation can be used to correct the yaw angle.
7) Use OmniMount
By default, VMX-pi's motion processing requires the unit be mounted horizontally, parallel to
the earth's surface; the yaw (Z) axis should be perpendicular to the earths surface.
If you need to mount VMX-pi vertically or upside-down, you will need to enable the
"OmniMount" feature in order to get reliable, accurate yaw (Z) axis readings.
8) Learn how the sensor behaves by using the navXUI
The navXUI provides insight into the key VMX-pi IMU features, and can help debug issues you
may encounter when integrating VMX-pi onto your robot. Running this user interface is highly
recommended for anyone using VMX-pi.
drift over time (approximately 1 degree/minute). While this
if VMX-pi is not mounted horizontally

Terminology

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