Classification of Industrial Robots
There are a number of ways in which industrial robots may be classified. Such
classifications are broad statements describing the important features possessed by the
robots. A classification should not be confused with a specification. A classification is a
means of placing a particular robot into a broad category or group where it can be
compared with like robots in the same group for suitability for a particular application. A
specification is a factual description of the robots size, capacity, capability, geometry etc.
It is possible for a robot to fall within many systems of classification depending on the
purpose for which it is being considered. Some common means of robot classification are
Industrial robots may be grouped according to there structure or
design, this is known as their configuration. For example some robots have arms that
rotate whilst others can only move in straight lines. The terms degrees offreedom and
degrees of movement become important when considering robot configurations, since
they can significantly influence the space envelope within which the robot can operate.
Important considerations when selecting a robot concern its positioning
accuracy, its repeatability and its ability to traverse smooth and often complex contours.
Such considerations are a function of the type of control system employed. Terms such as
servo and non-servo controlled, open or closed loop control and point to point or
continuous path control describe common classifications of control systems. These will be
covered in depth later.
Industrial robots may be powered by hydraulic, pneumatic,
electrical and mechanical devices eg a high power lifting function will dictate a
hydraulically powered robot to be specified.
Industrial robots may be classified according to the particular task for
which they are employed eg suppliers may concentrate on welding robots or assembly
robots or material handling robots etc. This method of classification alerts the user to the
suitability of a particular robot to the required application.