Welcome to the Western Regional Strain Gage Committee (WRSGC)
We are a Technical Division of the National Society for Experimental Mechanics (SEM)

The strain gage was invented in 1936-1938 by two different people at almost the same time. They were situated at the east and west coasts in the USA and they did not, have any contact with each another. Professor Arthur C. Ruge of the Massachusetts Institute of Technology (MIT) was one of the inventors and the other was Edward E. Simmons of the California Institute of Technology (Caltech). Professor Ruge submitted the bonded wire ‘resistant strain gage’ idea to the MIT patent committee. The reply of the MIT patent committee reads: ‘ . . . this development is interesting; the Committee does not feel that the commercial use is likely to be of major importance… any rights which the Institute may have in this invention should be waived in your favor . . .

Professor Ruge and his colleague Professor Alfred V. deForest approached the heavy machine manufacturer Baldwin-Southwark Corp. to consider the production and sale of strain gages under a license agreement. The first answer by Baldwin-Southwark to Ruge-DeForest’s license offer was: ‘We are in the locomotive business and are not going to make postage stamps’. After an impressive demonstration of strain gage performance in 1939, a cooperation started between Ruge-DeForest and Baldwin-Southwark. In 1941, they got their first sizeable order of 50,000 for the SR-4 gage (the initials S and R honor the inventors). The strain gage invention was patented by the United States Patent Office on June 6 in 1944.re

In 1955, Ruge and deForest sold to Baldwin-Lima-Hamilton
(BLH). In order to speed the industry acceptance and use
of the new SR-4 foil strain gage (shown below)

Fred Singdale of BLH started a technical group consisting of major users of strain gages. Below is the invitation that Professor Peter Stein received to attend the first SR-4 Committee Meeting that took place on April 18th, 1956. The SR-4 Committee later became known as the Western Regional Strain Gage Committee. The group would not only spread the use of foil strain gages, but also influence manufacturers into conducting new research and development programs to further that art of strain gage technology in general.

WRSGC was established to promote a free interchange of information about strain measurement techniques including:

  • State-of-the-art strain gage research
  • Development & application of strain gages for
    all environments
  • Strain measurement & connection techniques
  • Strain gage based transducers
  • Signal conditioning, data acquisition systems &
    real-time display