Mumbai University > Mechanical Engineering > Sem 8 > Industrial Engineering And Management

Marks: 5M

Year: May 2015

Therbligs are 18 kinds of elemental motions used in the study of motion economy in the workplace. A workplace task is analyzed by recording each of the therblig units for a process, with the results used for optimization of manual labor by eliminating unneeded movements.

Although motion study and Therbligs are usually associated with the workplace they can equally be used to optimize other processes, for example in the home. The theory is that by analyzing and optimizing the steps involved in a task time can be saved. In a factory, saved time means higher productivity. In the home saved time on chores means more leisure time.

Therbligs represent basic units of motion and activity. The list of Therbligs has evolved over the years. Today it is common to use 18 such elements, however originally the Gilbreths developed a system with 15. Clearly some Therbligs will be more appropriate to certain tasks than others. The whole set of 18 will not always be used.

How to use Therbligs

The activity of workers is first recorded and analyzed. The individual sequences of motions can be broken down into their component Therbligs and timed. The timing is usually performed in milliseconds.

The times taken can then be compared to industry norms (there are published tables for these). If workers are routinely taking longer than expected for a particular Therblig then there might be a reason that can be easily fixed, for example by investing in better equipment or rearranging the workspace.

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