9.1: Introduction to Moving-Frame Kinematics
- Page ID
- 50042
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An understanding of inertial guidance systems for navigation of vehicles and robots requires some background in kinematics. Central in our discussion is the use of multiple reference frames. Such frames surround us in our daily lives:
- Earth's latitude and longitude
- Forward/backward motion relative to current position
- Right/left motion
- Axes printed on an inertial measurement unit
- Vehicle-referenced coordinates, e.g., relative to the centroid
We first describe how to transform vectors through changes in reference frame. Considering differential rotations over differential time elements gives rise to the concept of the rotation vector, which is used in deriving inertial dynamics in a moving body frame.