1. Robotic repositories for off-line programming and calibration

Originally, robots did not have reference frames linked to their base and terminal organ, but rather an initial joint configuration in space. This initial configuration, from which other robot configurations were generated to achieve a given trajectory, was a constraint for managing the robot's available work volume and obstacle avoidance.

These disadvantages were eliminated by the adoption of a coordinate system placed at the base of the robot (which would become the cell reference frame) and additional reference frames placed on the end unit, on the tool and then on all the cell's constituent parts. The introduction of these reference systems also enabled robot manufacturers to add easy-to-use programming functions such as symmetries, translations, spatial offsets, etc.

These functions can only be effective in terms of precision if the...