Final answer:
Six parameters are required to describe a pose in 3D space: three spatial coordinates and three rotations around the x, y, and z axes. The three conventions for describing rotations are Euler angles, axis-angle representation, and quaternion representation. The quaternion representation is commonly used in ROS.
Step-by-step explanation:
In order to describe a pose in 3D space, six parameters are required. These parameters are the three spatial coordinates (x, y, z) and the three rotations around the x, y, and z axes. The rotations are commonly referred to as roll, pitch, and yaw.
Three conventions for describing rotations are the Euler angles convention, the axis-angle representation, and the quaternion representation. The Euler angles convention decomposes rotations into three consecutive rotations around each axis. The axis-angle representation describes a rotation as a unit vector indicating the axis of rotation and an angle of rotation. The quaternion representation uses four parameters to describe a rotation, providing a compact and efficient representation.
The most commonly used convention in the Robot Operating System (ROS) is the quaternion representation. This convention is widely used in robotics due to its mathematical properties and ease of use for computational purposes.