An approach to assessing motor workload in assembly tasks by the use of predetermined-motion-time systems

Starting from the problem of how to identify 'motor workload' in assembly tasks, it is pointed out that the concept of assessing workload can be understood axiomatically. Indices for rating motor workload can be pragmatically derived from predetermined-motion-time systems like 'methods-time measurement' or 'work factor'. The practicability of such indices is exemplified. A computer-aided procedure to apply this method is introduced. First experiences in practice are reported. The results demonstrate the utility of that approach to differentiate not only various tasks but also between manufacturing departments within a plant or enterprise. The current boundaries for the validation permit an absolute but limited rating. The application therefore concentrates at present on identifying the state of different designs of manual operations, workplaces and working conditions for assembly tasks.