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 as follows:


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.

Control System

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.

Power Transmission

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.