Coordinate System¶
In robotics, coordinate systems are expressed as a joint coordinate system and a 3D spatial coordinate system.
To control or understand the movement of a robot, it is necessary to express its position and movement in space numerically. The reference for this is the Coordinate System. A coordinate system is a reference frame that mathematically represents position and orientation, and two types of coordinate systems are generally used in robotics:
Joint Coordinate System: This is a coordinate system used to define the positions of the robot’s joints and is more familiar to the robot than to the user.
Cartesian Coordinate System: The Cartesian coordinate system is a method of representing the robot’s position and posture with orthogonal coordinates of X, Y, Z and rotation values (u, v, w) or (Rx, Ry, Rz). It represents the position of the robot’s end effector by its position and orientation in 3D space, and is a coordinate system that is intuitively easy for humans to understand.
Each coordinate system has a different purpose depending on how the robot’s movement is expressed, and an appropriate coordinate system is selected and used according to the situation.