In 1911 Frank Gilbreth, an engineer and his wife, Lillian, a psychologist, published the book, "Motion Study" which placed emphasis on the patterns of movement that were made by factory workers in their tasks. From their observation a classification system consisting of 17 basic hand and arm activities evolved. Typical motions, such as "reach" and "grasp" were described and coded into units that could be precisely described and timed. These units became known as "therbligs" (Gilbreth spelled backward with the "th" unreversed) and evolved to a universally accepted basis for human movement analysis in the workplace. The concept led to continuing refinement of motion descriptions. Precision timing with motion picture photography provided "micromotion" descriptions with a precision of milliseconds and even microseconds in special cases. The information was used for workstation design, safety analysis and for setting work rate standards during union negotiations. With the time factor and the motion factor considered together, workplace tasks could be redesigned to provide increased output, improved worker comfort and safety and, of course, a payoff in the profit bottom line. Overall, micromotion analysis and task redesign led to higher efficiencies in the manufacturing environment. However, as time and motion standards for specific tasks were set, it became apparent that all workers did not have the same talents and capabilities. Attention in the 1930's was thus directed to placing more emphasis on worker selection and training.

© 1996 John Lyman

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John Lyman can be reached through Armchair World at lyman@armchair.com.

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