Basic Characteristics RAPID

Coordinate Systems Motion and I/O Principles
The base coordinate system is located on the base of the robot:
- The origin is situated at the intersection of axis 1 and the base mounting surface.
- The xy plane is the same as the base mounting surface.
- The x-axis points forwards.
- The y-axis points to the left (from the perspective of the robot).
- The z-axis points upwards.
1.2.2 World coordinate system
If the robot is floor-mounted, programming in the base coordinate system is easy. If,
however, the robot is mounted upside down (suspended), programming in the base
coordinate system is more difficult because the directions of the axes are not the same
as the principal directions in the working space. In such cases, it is useful to define a
world coordinate system. The world coordinate system will be coincident with the base
coordinate system, if it is not specifically defined.
Sometimes, several robots work within the same working space at a plant. A common
world coordinate system is used in this case to enable the robot programs to
communicate with one another. It can also be advantageous to use this type of system
when the positions are to be related to a fixed point in the workshop. See the example
in Figure 2.
Base coordinate system robot 2
Z
Y
X
z
Figure 2 Two robots (one of which is suspended) with a common world coordinate system.
6-4 RAPID Reference Manual
y
World coordinate system
x
Z
Y
X
Base coordinate system robot 1