Global Coordinate System
- Denoted X,Y
- Often attached to Earth but can be attached to other objects as needed
- Absolute positions, velocities and accelerations are with respect to the GCS
Inertial Frame
- System that the coordinate system is attached to has no acceleration itself
- Sign convention:
- All angles are measured according to right hand rules
- Counter-clockwise(CCW) angles, angular velocities and angular accelerations are positive in sign.
Local Coordinate System
- Denoted x,y
- Attached to a point of interest
- Can be rotating
- local rotating coordinate system → LRCS
- local non-rotating coordinate system → LNCS
- Common points of interest: pin joint, center of gravity, etc.
- Use local coordinate systems to make analyses more straightforward
- Necessary when analyzing kinematics