Therbligs
The term Therblig is an anagram of "Gilbreth" and was coined by Frank and Lillian Gilbreth for their system of studying, timing and analysing the motions of workers. Therbligs are usually aimed at manual tasks and are often used in the field of time and motion studies.Although motion study and Therbligs are usually associated with the workplace they can equally be used to optimise other processes, for example in the home. The theory is that by analysing and optimising 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.
What Are Therbligs?
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.In today's world of computer software we probably need a new version of Therbligs to represent user interface interaction. I'm sure someone somewhere has produced one.
How to Use Therbligs
To use Therbligs, the activity of workers is first recorded and analysed. 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.
Minimize Your Therbligs
The real key to using Therbligs is to try not only to speed them up but to reduce them. The Therbligs for a process can be recorded on a Simultaneous Motion (Simo) Chart using special symbols. The Simo chart can then be analysed to look for ways of simplifying the process. This can both increase worker productivity and reduce fatigue.Simos were probably the first work simplification flowcharts. Originally the Simo chart was drawn on paper. Today, of course, you can buy software to assist in the task.
Final Thoughts
Analysing and minimising Therbligs can provide useful input into the optimisation process, however they should not be treated as the only factor. Sometimes "optimising" a procedure can have unexpected consequences. Workers are humans not machines.There's a famous story concerning Frank Gilbreth himself. He attempted to study the way he shaved in the morning in order to speed the process. Eventually he tried using two razors at once. He reported that this was a "success" in the sense that he saved around 90 seconds shaving time. Unfortunately he then had to spend several minutes patching up the cuts!
Without employee buy-in, involvement and reward any "time and motion" analysis risks shaving the business more quickly but making damaging cuts in staff relationships and morale.